PUBLIC HEALTH ASSESSMENT
TERRY CREEK DREDGE SPOIL AREAS/HERCULES OUTFALL SITE
BRUNSWICK, GLYNN COUNTY, GEORGIA
The Terry Creek Dredge Spoil Areas/Hercules Outfall site (the Terry Creek site) is in the city of Brunswick, Glynn County, Georgia. The site comprises two dredge spoil areas, a mobile home park, and the Hercules Outfall. It was proposed to USEPA's National Priorities List (NPL) on April 1, 1997. The two dredge spoil areas contain contaminated sediments dredged from the Dupree and Terry Creeks and placed in adjacent tidal marshes. The outfall area, where Hercules Inc.--a former pesticide plant--discharges waste water to Dupree Creek, as well as Terry and Dupree Creeks and adjacent surface water drainage areas, are part of the site. The Hercules, Inc. facility itself, however, is not part of this proposed NPL site. From 1948 through December 1980, Hercules (formerly known as Hercules Powder Company) produced as a major product toxaphene, a polychlorinated camphene (PCC) insecticide. Since 1972, when PCC in waste effluent from the Hercules manufacturing plant in Terry and Dupree Creeks was first restricted, the concentration of PCC in environmental samples such as sediment and fish has decreased significantly. In that regard, it is important to note that Terry and Dupree Creeks are used for fishing and crabbing.
Seafood consumption remains the main source of toxaphene exposure for people at and near the Terry Creek site. Components of technical grade toxaphene, its breakdown products or both have been detected in edible fish at Dupree and Terry Creeks. Thus additional, current information on quantitative and qualitative determinations of PCC residues in seafood from the Terry Creek area is needed. Such information will reduce any uncertainty regarding the level of toxaphene in fish, as well as the toxicologic meaning of such data. Accordingly, based on these data gaps, ATSDR considers this site to be an indeterminate public health hazard.
ATSDR recommends limiting consumption of contaminated seafood from Dupree and Terry Creeks. During the cleanup of PCC-contaminated sediments, the Georgia Environmental Protection Division, Coastal Resources Division, and the US Environmental Protection Agency recommend that people refrain from fishing or swimming in all of Dupree Creek and Terry Creek north of Torras Causeway to 2 mile west of its confluence with the Back River. Next spring, GA EPD will update the fish consumption guidance for this site, based on fish species at different locations. Moreover, because of contamination with PCBs and mercury from unknown sources, the GA DEP and USEPA recommend that consumption of silver perch (yellowtail) caught south of Torras Causeway to Lanier Basin be limited to one meal per week. According to the National Shellfish Sanitation Program standards--which are based on biological hazards--clams, mussels, and oysters in these waters are deemed not edible. Still, people eating fish from nearby areas can lower their risk of ingesting organic contaminants such as polychlorinated biphenyls (PCBs) by removing fatty tissue before cooking as well as by eating small (i.e., younger) fish.
Limited potential for human exposure exists at levels that would be of health concern in other exposure pathways such as soil, sediment, surface water or groundwater. Although unrelated to the Terry Creek site, based on community concerns and data collected by the Georgia Department of Natural Resources, ATSDR will continue to evaluate air data, if new data becomes available. Also, although asthma is a common health complaint of residents living near the site, the cause of that asthma is unknown.
In this public health assessment, the Agency for Toxic Substances and Disease Registry (ATSDR) evaluates the public health importance of the Terry Creek Dredge Spoil Areas/Hercules Outfall (the Terry Creek site) in Brunswick, Georgia. In April 1997 this site was proposed to the National Priorities List (NPL). The Superfund law (the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 [CERCLA] as amended by the Superfund Amendments and Reauthorization Act of 1986 [SARA]) requires ATSDR, among other things, to conduct public health assessments of a hazardous waste site within 1 year of that site's proposal for the NPL.
ATSDR, in Atlanta, Georgia, is an agency of the U.S. Department of Health and Human Services. Public health assessments are one part of the process ATSDR uses to review environmental and health outcome data--as well as community health concerns--to determine possible adverse health effects. In addition, this public health assessment recommends actions to reduce, prevent, or more clearly identify site-related actual or potential adverse health effects.
The Terry Creek site comprises four areas: two dredge spoil areas (Areas 1 and 2), a mobile home park area (Area 3), and the Hercules Outfall. The site also includes Terry and Dupree Creeks and adjacent surface water drainage areas. The Hercules facility, where chemical products (excluding, since 1980, toxaphene) are manufactured from pine resins, is not part of the proposed NPL site. These source areas and the Hercules facility are in the Atlantic coastal region of the southeastern United States, and are all east of the city of Brunswick in Glynn County, Georgia. The Terry Creek site itself is located east of Highway 17 and north of the Torras Causeway.
From 1948 through December 1980, Hercules, Inc. (Hercules was formerly known as Hercules Powder Company) produced as a major product toxaphene, a chlorinated-hydrocarbon pesticide. Toxaphene is a yellow-to-amber waxy solid that smells like turpentine1. It is a mixture of at least 177 significant individual compounds and is approximately 67-69% chlorine by weight. Toxaphene is produced by reacting chlorine gas with camphene, a derivative of turpentine. Hercules extracted turpentine from pine stumps or from pulp mill liquor 2. The reaction was controlled by using a solution of carbon tetrachloride that was subsequently evaporated from the product and recycled. Hydrogen chloride and unreacted chlorine gas were absorbed in water to form hydrochloric acid. Some of the hydrochloric acid was then sold as a commercial acid and the remainder was neutralized with limestone. After 1970, the liquid waste containing toxaphene was sent to a settling lagoon . Toxaphene was adsorbed into solids, dredged from the lagoon, retained on site2 and later deposited in off-site landfills. Toxaphene, also known as polychlorinated camphenes (PCCs), was used in the United States, primarily in the South, to control pests on cotton and other crops. In 1982 the use of toxaphene was restricted, then in 1990 was banned in the United States 1. Through 19893 Hercules used Terry Creek as a navigational channel for transporting raw materials such as pine stumps. Terry Creek merges with the Back River, which empties into St. Simons Sound and the Atlantic Ocean.
Until 1972 Hercules released large volumes of waste water containing PCC (reportedly up to 200-300 pounds of toxaphene per day) from a waste water discharge point at the confluence of Dupree and Terry Creeks 3. In 1972 Hercules was required under the Clean Water Act to build and use a waste water treatment plant to control and minimize the amount of toxaphene discharged 4. The toxaphene content of manufacturing plant effluent ranged from 2,332 parts per billion (ppb) in August of 1970 to 6.4 ppb in June 1974 5.
The U.S. Army Corps of Engineers (USACE) constructed a surface impoundment (including a dual dike system) to contain spoil dredged from Terry and Dupree Creeks. In 19726 a dike breaching occurred in a settling basin on the plant site. The dike on the perimeter of the impoundment was originally 22 feet high, and sediment and water were deposited directly into the impoundment. As the solids settled out of the dredged slurry, water drained through three weirs and back into Dupree and Terry Creeks 3. Breaches and discharge points have appeared in the dike throughout its history 6. Contaminants were found 3 miles away in almost all the indigenous oysters at St. Simons Sound 3. Contaminated oysters were also found as far as 7 miles away in Jekyll Island 24. The USACE dredged the channel again in 1978, 1983, 1987, and 1988/1989 4.
In 1976, Hercules received its first National Pollution Discharge Elimination System (NPDES) permit for an outfall (001) discharging to Dupree Creek. The permit restricted toxaphene to a daily maximum of 1 pound per day and a daily average of 0.5 pounds per day 3. Toxaphene discharge was later reduced to 0.00081 parts per million (ppm ). Through 1993 numerous violations of the permit were issued. The releases that occurred after 1980, when toxaphene production at Hercules had ceased, were from waste water surface impoundments and runoff at Hercules. By the summer of 1984, the toxaphene production facility at Hercules was completely dismantled 7.
In 1994 the Georgia Department of Natural Resources requested that ATSDR provide assistance in evaluating the results of residential surface soil samples collected adjacent to the Hercules facility. Nine private-residence yards on the north side of the facility (where the toxaphene waste water impoundments are located) were sampled and analyzed for toxaphene. Toxaphene concentrations ranged from 0.055 to 1.83 ppm. ATSDR concluded that these toxaphene concentrations in surface soil did not pose a short- or long-term health threat to the residents 8.
In 1995 the Brunswick/Glynn County Community Based Environmental Protection (CBEP) project began to provide a comprehensive analysis of the environmental status of the area 9. The CBEP project is a joint effort between the United States Environmental Protection Agency (USEPA), the Georgia Environmental Protection Division (GA EPD), and other federal, state, and local agencies, and the community. The Terry Creek site is within the Brunswick CBEP project area (Figure 1). Three industrial facilities in the Brunswick area are being cleaned up under federal Superfund statutes: LCP Chemical-Georgia, Inc., Brunswick Wood Preserving, and the Hercules 009 Landfill. In addition to these Superfund sites, about 17 other potentially hazardous waste sites are in the Brunswick area (Figure 1). Where applicable, information collected for the CBEP project has been used in this public health assessment.
In addition to being part of the CBEP project, ATSDR once listed the Terry Creek site as an environmental justice site. Environmental justice is the fair treatment and meaningful involvement of all people regardless of race, ethnicity, culture, income or educational status with respect to the development, implementation and enforcement of environmental laws, regulations, and policies 10. The Office of Urban Affairs (OUA) at ATSDR was involved at the site until 1999.
In August 1997 and January 1998, ATSDR team members for the Terry Creek site visited the area. These visits are discussed below.
Carl Blair and Laura Frazier, ATSDR team members, visited the Terry Creek site on August 5 and 6, 1997. At the Coastal Health Unit they met with Dr. Brooks Taylor, District Health Director, Jane Perry Britt, an environmental health specialist with the Glynn County Health Department, and Randy McCall, also with the Coastal Health District. It was decided that the Health Department would conduct a simple survey of the residential areas adjoining the contaminated creek areas to obtain information on the number of residents, and an indication of whether they were fishing locally.
In the afternoon of August 5, 1997, Captain Anthony Blount of the Department of Natural Resources took ATSDR representatives by boat to the Terry Creek area. They observed the Riverside Development, which included about four homes along the marsh coastline of Terry Creek. The majority of this subdivision is on the coastline of the Back River, a section less likely to be directly affected by dredging of Terry Creek (at receding tide, the Back River flows south; thus the contaminants would be considerably diluted when they return with the flooding tide 5 to the homes north of the confluence of the Terry Creek and the Back River). The residents use the docks on the Back River. Along Dupree Creek, the Hercules Plant can be seen in the distance, as well as an abandoned property that was formerly a paint company (Dixie Paint, later the O'Brien Corporation), and a retirement home. The main dredge spoil area is generally well-vegetated and appears to be near, or below, sea level. A dike, without vegetation on its top surface, surrounds the dredge spoil. A fisherman was also seen fishing in the Back River off the Torras Causeway.
On January 21, 1998 the ATSDR team for the Terry Creek site (Dr. Shan-Ching Tsai, Laura Frazier, Linda West, and Diane Drew) visited the Brunswick area and several area hazardous waste sites. On January 20 and 21, the team held public meetings to gather community concerns about the site. Ms. Marsha Pierce from the Glynn County Health Department drove the team by the Terry Creek site, the Hercules 009 Landfill, Altama Elementary School, LCP Chemical, Brunswick Wood Preserving, and the Georgia Pacific paper mill. She provided an overview of activities at each site.
Brunswick is home to both a commercial fishing port and a thriving seafood industry 9. Many tourists visit the area for such attractions as St. Simons and Jekyll Islands. Near the Terry Creek site, in Terry and Dupree Creeks, people use small boats for recreational fishing and crabbing. Tidal marshes provide feeding and breeding habitat for migratory birds and other animals. The average tidal range (the change in water levels between high tide and low tide) is about 7.5 feet 11. The marsh vegetation is primarily smooth cordgrass Spartina alterniflora and needle rush Juncus roemerianus.
Based on 1990 (and 2000) U.S. Census data approximately 4,837 (4,270) persons are within a 1-mile radius of the Terry Creek site (Figure 2) and a total population of 62,496 are in Glynn County. The statistics within a 1-mile radius of the site indicate about a 45 (40)% white and 53 (57)% black population. Approximately 12 (9)% of the population within a 1-mile radius of the site are children aged 6 years and younger. The nearest school, the Goodyear Elementary School, is located ¼ mile north of Area 1.
Both the Riverside Subdivision and the Terry Creek Mobile Home Park are near the site. In 1997, the Glynn County Health Department of the Georgia Department of Human Resources conducted a door-to-door survey in these neighborhoods to determine whether the residents were fishing. Staff members spoke with 36 residents living in the Riverside Subdivision, and 27 residents in the Terry Creek Mobile Home Park. Approximately 10 of these 63 residents (about 16%) indicated that they do some fishing 12. But no information was taken on the age and sex distribution of the fishing population who answered the doors during working hours--when the survey was conducted.The percentage of the fishing population could be much higher if all of the 4,000 local residents were contacted in the survey (See comment I-7, Appendix F.)
Using state or local health databases, health assessors might be able to determine whether the rates of certain diseases or causes of death are higher than expected in the area surrounding a hazardous waste site. This section identifies the relevant, available databases; their evaluation is addressed in the Public Health Implications section.
The Georgia Department of Human Resources (GDHR), Division of Public Health, Chronic Disease Prevention and Health Promotion Branch, Cancer Control Section, maintains data on mortality rates for selected cancers at county levels. ATSDR reviewed a summary on mortality rates for the period of 1988-1992 and evaluated these data in the Health Outcome Data Evaluation section. The GDHR and local public health officials were also contacted for existing aggregated, tabulated, or computerized health information sources. The state and local health departments collected vital statistics such as birth data and data on the most common causes of death, such as neoplasms (tumors) and diseases of respiratory systems. Some relevant information from these sources was reviewed by ATSDR.
The smallest geographic units for the health outcome data are at county levels. The 1990 U.S. Census reported a total population of 62,496 in Glynn County, and a resident population of 4,837 persons within 1 mile of the Terry Creek site. No computerized or tabulated health outcome data have been identified that exclusively address the small resident population near the Terry Creek site.
ATSDR obtained health and environmental concerns from 63 residents living near the Terry Creek site and from community groups and leaders. Because concerns about other issues and sites were also considered relevant, community concerns were not limited to the Terry Creek site. ATSDR solicited health concerns through a mailing, public availability sessions (one-on-one sessions with ATSDR staff) and other meetings, advertising the ATSDR toll-free number, and visiting nearby residences.
In December 1997, ATSDR advertised public availability sessions to be held on January 20 and 21, 1998, and solicited health concerns via mail and phone. Residents of Riverside Development and Terry Creek Mobile Home Park were targeted, as well as other area residents near the source areas (Figure 2). Each person received notice of the meetings, and received a fact sheet on public health assessments. Information was sent to approximately 350 residences and a dozen businesses.
ATSDR held the public availability sessions (PASs) to gather community concerns on the Terry Creek site. Eighteen residents attended the PASs. Residents along Terry Creek Road were surveyed to determine their source for drinking water and whether they had any concerns about the site. Nine residents on Terry Creek Road responded.
ATSDR representatives spoke with 27 residents (the 18 residents who attended the PASs and the nine residents surveyed on Terry Creek Road) living near the Terry Creek site. Seven residents (about 26%) reported that they, or their family members, had asthma or respiratory problems. Most residents did not think their respiratory problems were related to the contaminated dredge spoil. Other health complaints of one or more individuals are summarized in the Public Health Implications section of this public health assessment.
Concerns/Questions from the Community
Below are the health concerns and questions from the community, and ATSDR's responses:
Concern: People should be informed about the health hazards of eating contaminated seafood. Due, however, to the tourism industry, notifications to the public are often limited. Additionally, some community members fish at a city dock in Overlook Park (near Lanier Basin). Is seafood from this area safe to eat? Is the seafood or fish from the area creeks and rivers safe to eat ? Have fish from the Back River been analyzed, and are they safe to eat?
Response: The public should be appraised of health hazards, particularly in an area where tourism is important. Due to the cleanup operation of toxaphene-contaminated sediments, the Georgia Environmental Protection Division, Coastal Resources Division, and the U.S. Environmental Protection Agency recommend that people refrain from fishing or swimming in all of Dupree Creek and Terry Creek north of Torras Causeway to 2 miles west of its confluence with the Back River 13. Additionally, they recommend no more than one meal per week of silver perch (yellowtail) caught south of Torras Causeway to Lanier Basin, because of contamination with PCBs and mercury from unknown sources. Clams, mussels, and oysters in these waters are not edible, based on the National Shellfish Sanitation Program standards 13. This ban is related to a microbiological hazard. Persons fishing in Terry and Dupree Creeks should follow the fishing regulations and consumption guidelines as outlined above and as published by the Georgia Department of Natural Resources. Based on data gaps in the current knowledge of PCC residues in fish and their toxicity to humans, ATSDR recommends that exposure to contaminated seafood from Dupree and Terry Creeks be limited.
Concern: Raw sewage is sometimes in the streets after rain storms when the system is overloaded and could contribute to health problems.
Response: Raw sewage could contribute to health problems such as diarrhea. Residents should make calls to the city or county public works department when such an event occurs. This issue should also be taken up by local health officials and citizens who wish to pursue it. A Georgia Environmental Protection Division regional office in Brunswick handles such issues (Phone: 912 2647284). The sewage problem is unrelated to the Terry Creek site.
Concern: Private wells could be contaminated by seepage from Hercules. Is water from the community well at the Terry Creek Mobile Home Park contaminated? Is the water from the community well safe to drink?
Response: Private wells are unlikely to be affected by seepage from the Terry Creek Dredge Spoil Areas--the contaminants (toxaphene and metals) are held primarily by soil and sediment. Also, the concentrations of toxaphene in surface water are low to non-detectable. In September 1995, two nearby private wells and the community well at the Terry Creek Mobile Home Park were analyzed for toxaphene and metals. Toxaphene was not detected with a method detection limit of 5 ppb. The maximum contaminant level (MCL) for toxaphene in drinking water is 3 ppb. The community well should be tested with a minimum detection limit below the MCL to assure residents their drinking water is safe. No metals exceeded ATSDR health screening criteria. A trace of mercury was detected in the community well at 0.41 ppb and one private well at 0.21 ppb 14. The MCL for inorganic mercury in drinking water is 2 ppb.
The community well at the Terry Creek Mobile Home Park is used for drinking water by some families, while others are buying bottled water. As of 2001, ATSDR received no new data for the community well. The closest municipal wells draw groundwater from the Upper Floridan aquifer (approximately 750 to 1000 feet below ground surface) and are unlikely to become contaminated from the Terry Creek site 14.
Concern: People are sent to other hospitals in Savannah, Georgia and Jacksonville, Florida, thereby affecting the health statistics reported for the area.
Response: As long as an individual gives a Brunswick address, that health outcome will be counted for Brunswick, even if they went to a hospital outside of Brunswick. Birth and death data are shared between hospitals and states.
Concern: When it rains, Hercules closes a gate to prevent contamination from entering the creeks, but runoff backs up into the community. That surface water runoff from Hercules then backs up into residential yards, and some of these yards have not been tested for toxaphene.
Response: According to Hercules, no such gate exists at the plant, and Hercules does not contribute to flooding. Hercules is unaware of any yards into which drainage is flowing or has flowed from ditches from the Hercules plant. In 1992 toxaphene in plant ditch sediment ranged from less than 0.24 to 1,300 ppm (average of approximately 262 ppm ) 15. The Georgia Environmental Protection Division required Hercules to implement a Best Management Practices Plan requiring Hercules to minimize the erosion of soil and the release of waters containing toxaphene. Site drainage is to the plant ditch (N Street Ditch, an open channel with a piped section) running primarily east to west across the site 15. On-site ditches carry surface water runoff into outfall 001 on Dupree Creek. A pipe section on the ditch and a culvert head wall are immediately west of Highway 17 15, and residents reported the runoff from Hercules backs up into residential yards. ATSDR recommends soil sampling for toxaphene of residential yards that receive, or have received, silty runoff from ditches on the Hercules plant site.
Concern: Because toxaphene has not been tested on humans, no one knows the levels that cause health effects. No contamination should be in the community. We shouldn't be told that certain levels of toxics are OK to have in our community.
Response: Toxaphene has caused cancers in laboratory animals. Still, there are no adequate human data to evaluate the carcinogenicity of toxaphene 1. Therefore, toxaphene is classified as a probable human carcinogen, and human exposure to it should be kept as low as possible. ATSDR's screening level for toxaphene is based on non-cancer effects in animal testings. ATSDR, however, added safety margins of 100 times to its screening levels. These safety margins compensate for the possible discrepancy of extrapolating from animal tolerance to human tolerance, and protect sensitive human populations, such as infants and pregnant women. ATSDR also added an additional modifying factor of 3 because toxaphene can alter behavioral and functional development in offspring.
As a result of human activity, some chemical contamination is inevitable in every community. Until 1990, toxaphene was used heavily as a pesticide in the South. Residues of toxaphene were transported to widely diverse places through the global movement of contaminated air. With the sensitive instruments available at modern chemistry laboratories, scientists detected toxaphene in fish samples from the Great Lakes as well as the remote lakes of the Yukon Territory in Canada 16.
Concern: Terry and Dupree Creeks could be contaminated by the Hercules 009 Landfill.
Response: Surface water from the Hercules 009 Landfill drains northeast to Belle Point Creek, which flows into the Back River and St. Simons Sound. Dupree Creek flows into Terry Creek, which flows into the Back River. It is very unlikely (i.e., only a remote possibility) that the Hercules 009 Landfill will contaminate Terry or Dupree Creeks; Belle Point Creek does not flow into Terry and Dupree Creeks 17.
Concern: Hurricanes and other storms could spread contamination from the dredge spoil areas to areas in Brunswick and out to the Atlantic Ocean.
Response: Storms could spread this contamination. This is one of the reasons USEPA proposed the Terry Creek Dredge Spoil Areas for cleanup under Superfund.
Concern: Besides Hercules, O'Brien Corporation released chemicals into Dupree Creek.
Response: A paint manufacturing facility (O'Brien Corporation) producing latex and oil-based paint was on the property adjacent to Dupree Creek (Figure 1). Waste solvents from the production of oil-based paints, such as toluene and xylene, were disposed off site. The latex paint wastes containing low concentrations of mercury, chromium, and lead 9 were solidified and deposited in an on-site landfill. The facility reported surface water discharges in 1988 and 1989 18. Facility estimates for surface water discharges were ¼ pound per year for acetone, ethylene glycol, toluene, and mixed xylenes. These chemicals were also released to the air until 1990, when the facility closed 18.
Concern: Current and past air releases from Hercules have affected our community.
Response: USEPA's Toxics Release Inventory database has air release data, as reported by Hercules, from 1987 through 1995. In 1995, air releases from the stacks included carbon disulfide, methanol, methyl isobutyl ketone, and mixed xylenes. Fugitive emissions included ammonia, benzoyl chloride, hydrazine, methanol, methyl isobutyl ketone, phthalic anhydride, styrene, and mixed xylenes 18. Historical emissions (1987-1995) included these chemicals as well as biphenyl, cumene, epichlorohydrin, ethylbenzene, hydrochloric acid, and propylene. Methyl isobutyl ketone has been consistently released from the facility and is the chemical released in the highest quantity from Hercules (from over 2 million pounds in 1987 to 807,000 pounds in 1995). Xylenes were measured in air during 1996 as part of the Brunswick/Glynn County Initiative. The maximum concentrations (approximately 8.0 micrograms per cubic meter (ug/m3) for o-xylene and 3.3 ug/m3 for m-xylene) were recorded at Station 3, emergency management station (EMS) directly west of the Hercules facility 18. The levels of these two xylenes in air are far below ATSDR's screening level for total xylenes (100 ppb or 434 ug/m3) and have no significant health consequence.
Concern: There are many upper respiratory problems in the community.
Response: Upper respiratory problems might be linked to air quality in the general area of Brunswick (see the previous response). But data are unavailable to determine whether there is an increased incidence of upper respiratory problems in the Brunswick area. ATSDR recommends further evaluation of air for respiratory irritants. Additionally, data in the Brunswick/Glynn County Initiative suggests further evaluation of air releases from Brunswick facilities is needed, based on levels of potential carcinogens such as acrolein, acetaldehyde, arsenic, carbon tetrachloride, and formaldehyde 19.
Concern: Several people mentioned lung cancer, which they attributed to smoking. Other cancer concerns were colon and brain cancers.
Response: The age-adjusted mortality rate for cancers of the colon and rectum in Glynn County was lower than the rates for Georgia and the United States generally, based on 64 cases in 5-year period (1988-1992) for this county. The mortality rate for brain cancer in Glynn County is higher than the rates in Georgia and the United States. That said, however, the brain cancers in Glynn County during this period have such a small sample size (<20 cases) the mortality rate might be unstable. The rate for brain cancer in Glynn County is higher than Camden County and McIntosh County but lower than Brantley County. Each of these three counties had only a few cases of brain cancer, but their mortality rates are unstable due to the small sample sizes.
Concern: Former workers from the Hercules Plant in Brunswick reported that on-site working conditions were unsafe and that workers were exposed to toxaphene and other toxic substances produced at the plant.
Response: This information was reported to the GA-EPD and USEPA/RCRA. They referred it back to ATSDR because, in their words, they "have no authority to investigate on-site worker safety issues." ATSDR reported it to Federal OSHA authorities for follow up.
Concern: Is eating produce from gardens near the creeks or contaminated areas safe?
Response: As long as the concentrations of toxaphene in soil of garden areas are low, produce will be safe to eat. So far, soil and sediment concentrations in residential areas have been low. Still, garden soils should be analyzed for toxaphene if contaminated dredge spoil or other toxaphene contamination is suspected.
Concern: Hercules sold compost they said was not contaminated, but some community members wonder if some contamination was present.
Response: ATSDR has no data to confirm or refute the presence or absence of contamination in compost. If there are off-site areas where Hercules compost was used, sampling a few of these areas to determine the presence of PCC is recommend.
Concern: Dogs near local ballfields seem to have a lot of seizures. Could pesticide usage on the fields be a contributing factor? What does this mean in terms of the safety of small children playing there?
Response: There are many possible reasons for dogs having seizures. The causes can be defined only after more information is gathered and evaluated. Besides the pesticides, young dogs that have not been vaccinated could suffer from distemper--a highly contagious viral disease that affects the nervous system and causes seizures. Any possible toxaphene poisoning cannot be evaluated without environmental data. Studies have been conducted to evaluate the response of dogs to various doses of toxaphene. They found that, for a 10-kg dog (one that weighs approximately 22 pounds), a single dose of 50 mg did not cause effects, but 100 mg of toxaphene caused convulsions. Additional dosage the following day produced salivation and vomiting. A dose of 150 mg toxaphene can be fatal to dogs 1. Chemical effects are more likely than distemper if fatality or other symptoms of the poisoning were observed. If ATSDR receives information from Brunswick citizens regarding dogs with seizures, the data will be forwarded to veterinarians at the Centers for Disease Control and Prevention (CDC) for evaluation. Children, as well as pets, should not be in an area of recent pesticide application. Although toxaphene usage as a pesticide was banned in 1990, any currently used pesticides should also be identified.
Concern: There has not been enough soil sampling in dredge spoil area #2. More samples should be taken.
Response: USEPA is planning further soil sampling to determine those areas needing cleanup.
Concern: Several people mentioned explosions at the Hercules plant and evacuation of people near their facility.
Response: ATSDR suggests that those interested in the history of evacuations contact their local fire department for information.
Concern: Glynn County is the most contaminated county in the U.S.
Response: There are three Superfund sites in Brunswick (LCP Chemical, Brunswick Wood Preserving, and the Hercules 009 Landfill) as well as one proposed Superfund site, the Terry Creek Dredge Spoil Areas/Hercules Outfall site. There were approximately 20 potentially hazardous waste sites identified in the Brunswick/Glynn County Community Based Environmental Protection Project area (Figure 1). ATSDR, however, does not have statistics to confirm or refute this assertion.
ATSDR evaluated available environmental monitoring data to determine environmental contaminants and identify specific areas that could be of concern on, or around, the site. Comparison values, which are health-based thresholds below which no known or anticipated adverse human health effect should occur, were used to make these determinations. These values allow an adequate margin of safety. In some instances, PCC concentrations exceeded comparison and background values for the area. This health assessment, therefore, focuses on such contaminants. Other contaminants (even those not known to be site-related, such as mercury) were also evaluated if they exceeded the screening criteria. Later sections of this public health assessment contain more detailed discussions of the potential for adverse human health effects as a result of exposures to PCC. Tables containing some of the environmental data used in this section are presented in Appendix B.
Toxaphene is strongly adsorbed by soil or sediments, has low solubility in water, and bioconcentrates in aquatic organisms, particularly fish and fish-eating organisms that are long-lived and do not readily metabolize or quickly eliminate the contaminant. Toxaphene is acutely toxic to fish at low parts-per-billion or high parts-per-trillion concentrations 34, 21. Aquatic organisms (crabs, fish, etc.) and plants (such as smooth cordgrass) could mobilize PCC out of the Terry Creek area. PCC in sediment could be redistributed during storms or when adjoining channels or water flow patterns are altered. In aerobic surfacesoil, PCC concentration decreased slowly, primarily through vaporization to the air. Half-lives (the time needed for the PCC concentration to decrease by 50%) of PCC in the soils are about 10 years 1 on average. In anaerobic marsh sediments, PCC components with high chlorine contents rapidly lost some of their chlorine and became degraded products with less chlorine contents. Half lives of these daughter PCC members are unknown.
People are most likely to be exposed to PCCs near the Terry Creek Dredge Spoil site through consumption of seafood. Ingestion of soil or sediment, particularly by children, is also feasible. Thus PCC in seafood and sediment are evaluated in this public health assessment. Because it is rapidly broken down and excreted, PCC does not appear to accumulate in the human body to any appreciable degree.
Exposure to toxaphene can occur both on site and off site and through more than one pathway. Therefore, toxaphene data has been included on the Brunswick area, outside the Terry Creek site. For example, soils in Brunswick near the Hercules plant were tested for toxaphene. This information is presented in the off-site section of the report.
The Terry Creek Dredge Spoil Areas/Hercules Outfall site is a 118-acre area, including creeks and adjacent surface water drainage areas. It comprises two dredge spoil areas (Areas 1 and 2), a mobile home park area (Area 3) and the Hercules Outfall. Area 1, an approximately 72-acre impoundment, is at the confluence of Dupree and Terry Creeks. It is on the other side of Dupree Creek, across from the Hercules plant. Area 2, a 58-acre impoundment, is located about 1,600 feet east of Area 1 near the Riverside Development residential housing area. Area 3, a 7-acre residential area (Terry Creek Mobile Home Park), is across Terry Creek from Area 1. It contains approximately 22 mobile homes. These areas are north of the Torras Causeway (Figures 1 and 2). USEPA's 1995-1996 sampling rationale has been to determine the presence or absence of contamination in these areas. Surface soil samples were taken at surface to 6 inches below ground surface, and subsurface samples were collected about 4 feet below ground surface 14.
In this public health assessment, Dupree and Terry Creeks are considered to be part of the proposed Superfund site. These creeks received historical PCC spills, and the potential migration of PCC from the dredge spoil areas. Historical data were also reviewed to obtain a perspective on PCC in various media 22, 23. But PCC levels in the Brunswick area have decreased in the past 20 years, so they might not be reflective of current conditions.
The Main Dredge Spoil Area (Area 1)
The main dredge spoil area consists of contaminated sediments dredged from the bottom of Terry and Dupree Creeks. In 1972, PCC concentrations in dredge spoil in Area 1 ranged from approximately 52 to 813 ppm 23. Soil samples were collected in September 1995 from three locations in Area 114. The PCC concentrations in surface soil were 18 to 240 ppm and in subsurface soil approximately 3.2 to 430 ppm (Table 1). In some cases, the PCC concentration in surface soil exceeded ATSDR's screening levels. Thus PCC was selected as a contaminant for further evaluation in this public health assessment.
Near Riverside Development (Area 2)
In 1972, PCC concentrations in dredge spoil of Area 2 ranged from approximately 0.8 to 151 ppm 23. Three locations in Area 2 were tested for PCC in September 1995 14. At these locations, PCC in surface soil averaged around 6.5 ppm (Table 1). PCC concentrations were highest (56 ppm or less) in the subsurface soil adjacent to Terry Creek.
Terry Creek Drive (Area 3)
Approximately 20 soil samples collected adjacent to Terry Creek Drive have been analyzed for toxaphene 14. Two surface soil samples--taken in September 1995--indicated the presence of PCC at concentrations ranging from 0.68 to 9.3 ppm (Table 1). In February 1996, composite samples of surface soil were collected at 13 locations in the Terry Creek Mobile Home area. The composite samples consisted of soil from approximately three locations in each yard. In most of the samples PCC was not detected. The maximum PCC concentration detected in composited soil from February 1996 was 0.49 ppm. PCC was detected in one out of three subsurface soil samples at 1.9 ppm (Table 1).
The yards of several residences adjacent to the marsh area contained miscellaneous chemicals of unknown origin. Two yards along Terry Creek Drive contained elevated levels of polycyclic aromatic hydrocarbons (PAHs) in which benzo-a-pyrene exceeded an ATSDR comparison value of 0.1 ppm. This indicated some localized contamination of surface soil from an undetermined source.
During receding tide, Terry Creek flows east for 1.3 miles and merges with the Back River. The Back River flows south for approximately 1.8 miles and empties into St. Simons Sound and the Atlantic Ocean 3. At flooding tide, the water in St. Simons Sound is pushed back to the creek and river 5. Data from 1972 indicates that PCC in surface water near Terry Creek was approximately 1.4 ppb 23. Surface water samples were collected in 1997 but did not contain PCC above the detection level of 5 ppb. At a detection level of 5 ppb, however, indication of PCC is not anticipated based on historical records. PCC is readily absorbed through skin contact and could be expected to cause problems for swimmers. But because PCC is absorbed by soil and sediment, its present concentrations in surface water should be low. Historically, it could have posed a hazard for swimmers, particularly when effluent discharge concentrations of PCC from Hercules were highest (around 1970). That said, however, the surface water of local creeks is not being used as a drinking water source.
Low concentrations of chloroform, carbon tetrachloride, and methyl isobutyl ketone were detected at a surface water sampling location in Terry Creek 25. Because, however, their concentrations did not exceed ATSDR comparison values for drinking water, they were not evaluated further. Some of these solvents were used in toxaphene manufacturing processes.
Elevated concentrations of toxaphene have been found in the sediments of Terry and Dupree Creeks and adjacent wetlands. In September 1995, about 14 sediment samples from the creeks and adjacent wetlands were analyzed for toxaphene. Toxaphene was present in most sediment samples at concentrations ranging from 0.16 to 2.4 ppm. Higher concentrations (8.5 to 60 ppm ) were found south of Torras Causeway on Back River, in Dupree Creek northwest of Area 1, at the Hercules outfall drainage ditch leading to Dupree Creek, and in wetland sediment upgradient of the site on Dupree Creek (Figure 3). In 1997, toxaphene concentrations in sediment of Dupree and Terry Creeks ranged from approximately 7.9 to 230 ppm 25. The highest concentration was found near the Hercules dock in Dupree Creek. In 1998, PCC concentrations from 0.62 to 33,000 ppm were found in 31 surface (0-1 ft) sediment samples from the Outfall Ditch 38. Their average concentration was 1,300 ppm.
Fish and other Seafood
Dupree Creek, Terry Creek, and the Back River are known fisheries and habitat for several federally endangered species such as the West Indian Manatee, Wood Stork, Loggerhead Sea Turtle, and Ridley Sea Turtle 3. The creeks provide fishing as well as blue crab collection sites for the general public 25. Fish species caught in nearby coastal areas include striped mullet, spotted sea trout, long-nose gar, blue angelfish, sheepshead, gizzard shad and others 27. Fish species caught recently in Terry and Dupree Creeks include yellowtail, spot, mullet, spotted sea trout, croaker, red drum, flounder, and whiting 28. Shellfish recently caught in these creeks include shrimp and blue crab 28. Fishing information was gathered in a door-to-door survey with 63 residents of the Riverside Development and Terry Creek Mobile Home Park who live on or near the contaminated areas of the Terry Creek site. Approximately 16% of them indicated that they do some fishing there 12. Thus human exposure to PCC through consumption of fish and other seafood is a likely exposure pathway at the Terry Creek site.
PCC concentrations in effluent from Hercules were highest in the early 1970s, prior to construction of a waste water treatment plant in 1972. Until 1972 3 Hercules released large volumes of waste water containing PCC (reportedly up to 200-300 pounds of PCC per day) from a waste water discharge point at the confluence of Dupree and Terry Creeks.
Historically, PCC contamination in seafood was not limited to the Terry Creek area but extended to St. Simons Sound 29 and Jekyll Island 24. Data from the early 1970s indicate toxaphene contamination of rough fish (Fundulus killifish), and seafood (anchovy, shrimp, oysters, and finfish) in the Terry Creek area 23, 24, 30. Some data on PCC levels in the rough fish (killifish or Fundulus heteroclitus) is shown in Table 2. Averages for PCC in Fundulus between 1970 and 1972 were around 50 ppm. In 1972 PCC in anchovies usually averaged around 10 ppm, with the maximum concentration reported being 236 ppm in 1970. Eight samples taken in 1973 and 1974 revealed anchovies in the Terry Creek area having an average PCC concentration of 2 ppm, whereas shrimp samples from the same time period showed less than 2 ppm 5. The toxaphene concentration in white shrimp in Terry Creek was usually around 10 ppm or below in the 1970s 23. Oysters taken from Terry Creek between 1967 and 1970 contained approximately 13 ppm PCC 24. In 1971, oysters in the Back River at Torras Causeway contained an average of approximately 2.6 ppm toxaphene 30. In 1972, however, the concentration dropped to 1.3 ppm 23.
Although the focus of recent data has been on finfish and shellfish, no data are available for recent PCC levels in oysters. Presently, oysters are neither harvestable nor edible near the Terry Creek site because of bacteria, and because of the lack of chemical information resulting from their omission from the sample collections (R Manning, GA DNR toxicologist, personal communication, September 8, 1997). Oysters, clams, and mussels are not harvestable and are under a shellfish ban as established by the National Shellfish Sanitation Program. This ban, which is not linked to the Terry Creek Dredge Spoil Site, extends to areas such as St. Simons Sound.
In October 1995, Hercules conducted an assessment to determine whether toxaphene discharges were affecting the edibility of fish and crabs in Terry and Dupree Creeks, adjacent to their facility 27. Composite tissue samples were collected at one station for spotted seatrout and at four stations for blue crab. Toxaphene was not detected in either fish fillets or crab meat in any of these samples. The detection limit was 50 ppb for blue crab and 250 ppb for spotted sea trout. The USEPA guideline is a 100-ppb screening level for no further action. This sampling effort garnered only one fin fish sample, from the furthest sampling station. The sampling goal for mullet was not met.
In February and March 1997, USEPA and the Georgia Environmental Protection Division (GA EPD) collected seafood samples from Terry and Dupree Creeks as part of the environmental sampling effort to support a clean-up decision. The samples provided some evidence that organic constituents similar to those found in toxaphene were detected in fish. The estimated PCC concentrations ranged from 1.9 to 27 ppm in forage fish samples (primarily Fundulus heteroclitus, a nonedible rough fish) and 1.6 to 3.9 ppm in four consumer fish samples. No substantial signs of metals were detected in fish. PCC concentrations were highest in fish at the Hercules effluent channel. Analyses of blue crab tissue (meat) indicated no substantial signs of organic or metal contamination 25.
In April 1997, the GA EPD collected 59 composite samples of seafood (38 finfish such as mullet, sea trout, drum and 21 shellfish such as crab and shrimp) from four areas in Terry and Dupree Creeks. GA EPD analyzed these samples for metals (e.g., mercury), PCBs, and toxaphene 28. GA EPD stated that toxaphene was not detected, and qualitatively described the toxaphene concentrations as below various detection limits ranging from 0.1 to 1.0 ppm (Table 4A). Further explanation of those toxaphene results in seafood samples is provided in Appendix D. Approximately 70% of the fish composites in the April 1997 data set contained PCB (Aroclor 1268) in low concentrations (0.04 to 0.18 ppm) 28. PCBs were not detected in shellfish (crabs and shrimps), but, again, oysters were not sampled. Approximately 30% of the fish samples contained mercury ranging from 0.11 to 0.31 ppm. Arsenic in shellfish was about 3 to 5 ppm (Table 4B), which was within the normal range of 4-5 ppm for fish and seafood 43. The GA EPD has requested some speciation of the arsenic to determine if a toxic form is present. No information is available for the sources of the PCBs, mercury, and arsenic noted above. Generally, arsenic in finfish, shrimp, and crab is present as arsenobetaine and other relatively nontoxic organoarsenical compounds 43, 47.
In addition to the complex composition of technical-grade toxaphene, the PCC compositions in fish differ from the reference standards, including the Hercules reference standard. The method used to calculate total toxaphene from chromatograms (e.g., total area method vs. 4 back peak method) also affects the estimated concentrations 32. USEPA detected PCC in all four fin fish samples collected in February/March 1997 with the total area method 25. On the other hand, GA EPD qualitatively determined that "toxaphene" was not detected in all fish samples collected in April 1997 at the same waste site, even though fin fish samples contained significant levels of unidentified components with gas chromatographic retention times within the envelope of toxaphene 48. GA EPD stated that "a match for toxaphene was called if the retention times and peak ratios in the latter half of the chromatogram matched an analytical standard of toxaphene. No hits were called in any of the fish samples"48. No detailed description on methodology was provided in GA EPD's draft release 28.
ATSDR formally received from USEPA the August 14, 1997 analytical protocol, of which the last- 4-peak method was intended to be used by USEPA and Hercules, and, probably, the GA EPD to analyze for toxaphene.ATSDR's concerns regarding toxaphene analyses are explained in Appendix D. ATSDR will continue to evaluate toxaphene monitoring data as it becomes available. USEPA is conducting similar evaluations and improving methods for quantitative evaluation of PCC.
In April 1998 ATSDR secured the services of Dr. Mahmound A. Saleh from Texas Southern University. His expertise was requested in estimating the total toxaphene concentrations in seafood samples from hard copies of the April 1997 chromatogram data. Appendix E contains Dr. Saleh's report. Based on the GA EPD data (mainly the hard copies of GC chromatograms), Dr. Saleh concluded that toxaphene is present at concentrations below 1 ppm in most fish samples. Nevertheless, he recommended more confirmation to prove the existence, and level of toxaphene concentrations in fish (Dr. Mahmound Saleh, personal communication, November 12, 1998). The fish with estimates of toxaphene ranging from 0.5 to 1 ppm were spot, flounder, croaker, and spotted sea trout from Dupree Creek, spot from lower Terry Creek, mullet and croaker from Terry Creek at the bridge, and spot from Lanier 33. Recently, GA EPD and the Skidaway lab made a second analysis of the April 1997 fish samples for individual PCC components with gas chromatography-electron capture detector(GC-ECD) and the specific instrumentation of gas chromatography-mass spectroscopy. The total PCC (the sum) concentration up to 26 ppm was reported (6/19/2000) for mullet. ATSDR will assess this new data in a later health consultation.
In a 1997 study by the Skidaway lab, PCC levels up to 1.2 ppm were found in the whole body of grass shrimp Palaemoletes pugio at this site 49. In August 1970 30 the PCC concentration in shrimp was 3.0 ppm.
In November 1997 26 rough fish (Fundulus) and sediment samples were collected from Terry and Dupree Creeks, and the compositions of the PCC residues in these samples were qualitatively determined. Only half a dozen PCC congeners were detected in the GC-MS chromatograms. Probably, a relatively small number of PCC congeners remained in the sediments and killifish in this site. The highest number of PCC congeners were found in Dupree Creek near the dock at the small lagoon draining the dredge spoil island (Station 4), and from the plant's discharge cooling water canal or Hercules Outfall (Station 7) 26. Quantitative estimates for total PCC levels were not performed in the November 1997 samples.
PCC is found in the Brunswick, Georgia area environment near the Hercules facility. The areas discussed in this section are not part of the Superfund site. Historical data indicates that PCC in oysters abated with distance from Terry Creek site. In the 1970s, PCC concentrations were 54 ppm at Terry Creek, 7.5 ppm at St. Simons Sound, and 1.0 ppm at Satilla River 24.
Fish samples analyzed in 1997 by Skidaway Institute of Oceanography showed PCC in liver and egg samples (fatty organs that are the best accumulators of PCC) from fish (sea trout, red drum, croaker, and flounder) caught in Dubignons Creek off Jekyll Island and in Purvis Creek, near the LCP site in Brunswick 34. Components of toxaphene were detected and confirmed in fatty organs of fish using state-of-the-art methodology (i.e., gas chromatography with electron capture detection, and mass spectrometric detection). Estimated toxaphene concentrations were 0.5 to 1 ppm on a lipid basis or 0.02 to 0.1 ppm wet tissues in fatty organs of the off-site fish. The small mullet fingerling (whole fish) and whole grass shrimp contained less than 0.01 ppm of total toxaphene. Sea trout eggs were also collected from the Skidaway River on the northern Georgia coast to serve as background control. Total toxaphene (on a wet weight basis) from the ova of sea trout from Skidaway River area was also below 0.01 ppm, the detection limit.
Plants and Produce
Vegetables in residential gardens have not been sampled and analyzed for toxaphene. Yet historical data indicates that the thin leaf blades of smooth cord grass in the salt marsh retained a toxaphene level as high as that in the sediment (about 30 ppm on the basis of dried leaf weight). The seed had a moderate toxaphene level and the root system was relatively clean 23. In sea water, toxaphene labeled with radioactive chlorine-36 was readily picked up through the roots by the stems and leaves of the smooth cord grass 5. The leafy vegetables in residential gardens could be contaminated if the cordgrass experience is applicable to leafy vegetables in contaminated local gardens.
Residential yards near the Hercules Brunswick Facility
In 1995 and 1996, residential yards in the vicinity of the Hercules Facility were sampled for toxaphene. Forty samples were collected to determine whether any off-site toxaphene concentrations are associated with the facility 35. Although toxaphene was not detected in most of the yards, eight yards were found to contain toxaphene concentrations ranging from 0.9 to 2.6 ppm. Newfields, Inc, a Hercules contractor, concluded that from a statistical analysis of these data, no pattern or trend of toxaphene dispersal from the facility was discernable.
In December 1996, residential yards in the vicinity of suspected sources of contamination were sampled as part of the Brunswick Community Based Environmental Protection Study. Thirty-four locations were sampled for toxaphene, which was found in three yards. Two of these yards had concentrations around 10 ppm (14 ppm on Stonewall St. and 9.1 ppm on Cook St.).
These results indicate some localized toxaphene contamination. Most of the soil samples from yards sampled between Fourth St. and Gloucester St. indicate that toxaphene could be present at levels ranging from 0.36 to 1.5 ppm.
In April 1996, soil samples were collected by GA EPD from several schools in Glynn County (Glynn Academy, Jane Macon Middle School, Risley Middle School, and the Risley Learning Center) and tested for toxaphene. No toxaphene was detected 36. In June 1996, USEPA collected soil samples at nine elementary, three middle schools, and 10 parks in the Brunswick area. Goodyear Elementary (the school closest to the Terry Creek Dredge Spoil site) was also sampled. ATSDR reviewed the June 1996 soil data and concluded that contaminants are not at levels of public health concern 36.
In November 1996 37 an environmental consulting firm conducted further soil sampling at Burroughs-Molette and Goodyear Elementary Schools. Although no toxaphene was detected using the characteristic peak method, toxaphene was quantified using a total area method. The total area method indicated possible degraded or weathered toxaphene-like compounds averaging less than 2 ppm.
Inhalation exposures to PCC are possible through volatilization of PCC in contaminated water or soil39. Inhalation exposures could have occurred during production of toxaphene at Hercules prior to 1980. PCC can be transported long distances in the air if it is adsorbed by particulate matter (dusts). The half-life is approximately 5 days for the vapor phase 39. The particulate form, however, is resistant to degradation 1. For the airborne PCC mixture, the atmospheric residence time is about 46-70 days 1.
During March and April 1996 19 GA EPD collected air data for the Brunswick/Glynn County area from ARCO, Brunswick College, Emergency Management Station (on the Hercules plant), Georgia State Patrol, Jekyll Island, and St. Simons Island. Air samples were analyzed for toxaphene, but none was detected 19. Data in the Brunswick/Glynn County Initiative suggest, however, that based on levels of potential carcinogens such as acetaldehyde, arsenic, carbon tetrachloride, and formaldehyde 19, further evaluation of air releases from Brunswick facilities is needed.
The limited available data used in this assessment originated from various sources over a span of more than 25 years. A wide range of data quality exists. Some reports were peer-reviewed and published in open literature, while other reports were internal publications. Some 1990s reports were formal, with detailed information in each part of the text, while other reports were in the form of draft releases, which provided raw numbers without using the formal format. There is huge uncertainty in some data sets relevant to contaminants at this waste site. ATSDR reviewed the available database and looked for any PCC mixture or individual PCC compound that could represent a potential health hazard to the public. It should also be noted here that historical data were gathered primarily for ecological studies, while current data have been collected to help USEPA determine remedies for site clean up.
Although many PCC components have now been identified and reference standards for about 20 PCC congeners are commercially available in the market 33, PCC analysis in environmental samples remains a developing field. PCC levels had been estimated by calculating the sum of selected peaks, the sum of all individual peaks, or the total area in the GC chromatogram. Because PCC is a complex mixture, it can be difficult to compare environmentally degraded and transported PCC with toxaphene standards or source materials. Even the standard references for toxaphene from various suppliers in the market differ in their compositions. Additionally, environmental processes such as translocation and transformation can, over time, change the PCC composition in environmental media. The specific processes include selective biota (e.g., Spartina alterniflora in the marsh) uptake, translocation or both, and atmospheric transformations, as well as benthos or sediment transformations or both (e.g., anaerobic dechlorination in the marsh sediment). These processes can affect the congener distribution. And in comparison to the Hercules toxaphene standard, they generally shift the pattern of PCC toward lower (fewer chlorines) chlorinated toxaphene components. Thus particularly when toxaphene concentrations are low, the method of analysis assumes great importance.
For the April 1997 data reviewed by Dr. Saleh, the hard copies of chromatograms indicate accurate analysis, and acceptable recovery and QA/QC criteria. Nevertheless, for future analyses of toxaphene in fish, methods other than GC-ECD have been recommended (Appendix E) 33. Information on the efficiency of sample extraction and detailed experimental procedures were unavailable in the data package for Dr. Saleh's review. Recently the earlier, April 1997 fish samples were analyzed again at Skidaway lab with efficient procedures and advanced instrumentation. PCC content up to 26 ppm was found in mullet. ATSDR will assess these new data in a later health consultation.
The recent fish samples were limited to the February/March 1997 samples and the April 1997 samples. The fish data from other times of the year are unavailable, and the seasonal fluctuations of PCC residues in fish are unknown. During the Memorial Day holiday (5/28/2001), croakers and whiting were caught with rod and line in this area by local anglers. On that day, an ATSDR staff (S.C. Tsai) made an unofficial visit to the site and spoke with the anglers.
USEPA is undertaking a removal operation to reduce areas of high PCC concentration in the creeks. Heavy machinery will be moving around at this site. Therefore, physical hazards commonly seen at construction sites are expected. Some type of restriction to exclude public access to the site during removal and remedial operations will be put in place.
Possible facilities that could contribute to environmental contamination in the Terry Creek area in Brunswick had to be identified. To accomplish this, ATSDR staff members reviewed information in the Brunswick/Glynn County Community Based Environmental Protection (CBEP) Project and in USEPA's Toxics Release Inventory (TRI) database.
Community Based Environmental Protection (CBEP) Project
In several areas in Brunswick, other than the Terry Creek area, toxaphene is concentrated on site. These sites include the Hercules Plant, the Hercules 009 Landfill, the 4th Street Landfill, the T-Street Landfill, and the Old Sterling Landfill. Clean-up levels were 0.25 ppm for residential soils near the Hercules 009 Landfill. Toxaphene is present in low concentrations in most areas in Brunswick due in part totoxaphene's historical release and its possible use as an agricultural chemical. Hercules was the only manufacturer of toxaphene in coastal Georgia 17. Although the use of toxaphene in the U. S.1 was restricted in 1982 and banned outright in 1990, the PCC residues remains in this site as a result of Hercules' previous discharges of PCC wastes into Dupree Creek.
Toxics Release Inventory (TRI)
To identify possible facilities that could contribute to the environmental contamination in Brunswick, ATSDR staff members searched the 1987-1995 files of the TRI databases for the area around the site 18. USEPA developed a TRI from chemical release information provided by industries for air, water, and soil. Two zip codes were searched for information in Glynn County near Terry Creek--31520 and 31521. For zip code 31520, five USEPA-regulated facilities in the TRI database were found: Brunswick Wood Preserving Co., Hercules Inc. (Gum and Wood chemicals), King & Prince Seafood Corp., LCP Chemicals, and Rich-Seapak Corp. For zip code 31521, three USEPA-regulated facilities were in the TRI database: Georgia Pacific Corp (Union St), Georgia Pacific Corp (W. 9th St), and O'Brien Corporation (Manufacturing Paints and Allied Products). With the exception of Hercules, no toxaphene source was found among any of these facilities for the period 1987-1995.
This section presents evaluations of the possible environmental pathways that help determine whether individuals have been, are being, or will be exposed to site-related contaminants. Environmental pathways can be completed or potential. A completed pathway indicates that human exposure to contaminants has occurred in the past, is occurring, or will occur in the future 41. A potential exposure pathway indicates that human exposure to contaminants could have occurred in the past, could be occurring, or could occur in the future. An exposure pathway can be eliminated from consideration if exposure has never occurred and never will occur. Tables presenting completed and potential exposure pathways for this site are in Appendix C.
Persons are most likely to be exposed to toxaphene near the Terry Creek site through consumption of seafood. Terry and Dupree Creeks are used for recreational fishing and crabbing, and those eating seafood from this area are likely to have been exposed to PCC through ingestion of contaminated seafood.
The air pathway is not likely to be a problem at this site. Still, past exposures could have resulted via air when the facility was manufacturing--and consequently releasing--toxaphene to the outfall. Additionally, some exposure through air could have occurred during dredging of contaminated sediments. Historical monitoring data for toxaphene in air are, however, not available.
Anyone, but particularly children, could accidentally ingest soil or sediment contaminated with PCC. But the Terry Creek contaminated areas are adequately vegetated, and the main dredge spoil area is remote, being accessible primarily by boat. Thus it is unlikely that low-level exposure to PCC in soils would cause harm to humans. Nevertheless, the soil is considered a potential exposure pathway because some contamination is present in residential soils and ingestion could possibly occur.
Produce from gardens
PCC may accumulate in produce (particularly leafy vegetables) grown in PCC- contaminated soils. Studies conducted during toxaphene's initial registration indicate that toxaphene is unlikely to be taken up by fruits or leafy vegetables. But many factors affect the uptake of toxaphene residues in soils. Organic carbon (log Koc = 2.47 - 5.0) and clay minerals in soils have a strong affinity to toxaphene, rendering it less available to plant absorption through interstitial water in soils (or sediments). Air movement over the plant leaves also favors the uptake of water and PCC in water solution. In addition, the composition of the sedimentary PCC residues can affect the plant uptake. In situ data indicated that smooth cord grass in the local marsh contained as much PCC as is found in the sandy sediment of a windy seashore 30. In an environmental chamber experiment with Cl-36-tagged toxaphene in sea water, the bioconcentration factors were found to be 0.67, 0.58, and 0.067 for cord grass roots, stems, and leaves, respectively 5.
That said, however, the concentration in produce will still be dependent on the concentration in the soil. So far, soil and sediment concentrations in residential areas have been low. As long as the concentrations of PCC in soil of garden areas are low, produce will be safe to eat. Garden soils should be analyzed for PCC if contaminated dredge spoil or other PCC contamination is suspected.
Toxaphene is adsorbed by soil and sediment (log Koc = 2.47-5.0); thus its concentration in surface water should be low. Toxaphene is also readily absorbed through skin contact. Currently, surface water is not thought to pose a hazard for the occasional swimmer or water skier. Historically, however, it could have posed a hazard for swimmers, particularly when effluent/discharge concentrations of PCC from Hercules were highest (around 1970). It should also be added that presently, the surface water of local creeks is not being used as a drinking water source.
The relatively low solubility of toxaphene in water and its strong adsorption by soil or sediment particles minimizes the leaching of toxaphene into groundwater. The private wells to the northwest of the Terry Creek Dredge Spoil areas are deep, drawing water from greater than 200 feet below land surface 45. In addition to the deep private wells, drinking water near the site is supplied by the City of Brunswick Water Department. Its closest well is approximately 4000 feet to the northwest 45. Additional information, however, is needed on the community well on Terry Creek Drive--residents use this water for drinking purposes. And data on groundwater contamination at the Hercules plant is also needed because it could contribute to contamination in surficial (shallow) aquifers.
PCC in fish and surface soils is the major concern for human exposure from the Terry Creek /Hercules Outfall site. Other contaminants from unknown sources in the general area include PCBs, mercury, arsenic, and numerous air contaminants. The air contaminants include acetaldehyde, arsenic, carbon tetrachloride, and formaldehyde19. Evaluation of the air emissions was not conducted because they were not site-related and are currently under evaluation by the State of Georgia Environmental Protection Division (GA EPD).
Discussion of the Possibility of Health Consequences
Health assessors determine possible health consequences by comparing a chemical exposure to epidemiologic evaluations of human exposures to that chemical. If assessors do not have valid human data, they use information from properly conducted animal studies. The type of data used for an evaluation is indicated for each chemical. Usually, there is little or no information on how much exposure is actually occurring at a site. So, to ensure that the public health is protected, it is assumed that maximum exposure has taken place. If, on the other hand, there are valid data on exposure of area residents to site contaminants, these will be used to decide whether an ongoing public health hazard exists.
PCC can reach area residents, especially subsistence anglers, mainly through consumption of fish. Ingestion of contaminated surface soils and sediment is another way area residents can be exposed to PCC. PCC can also enter the human body through skin contact.
Historically, oysters containing up to 54 ppm of PCC have been reported. But in 1972 the PCC levels were reduced to 1.3 ppm. Current PCC concentrations in oysters are unavailable. Still, because of sanitation problems, oysters are not harvested in this coastal area. Killifishes--resident rough fishes--accumulated 50 ppm of PCC in the past and currently report up to 27 ppm. In past decades, migratory food fish revealed up to 35.6 ppm, but few current quantitative estimations of PCC concentrations in food fish are available for this site. The current on-site concentrations are 3.9 ppm or less, based on semi-quantitative estimations on a limited number (four) of fish samples that were available in 1998.
To determine the potential for any human health risk resulting from consumption of PCC-contaminated fish at the Terry Creek site, ATSDR has selected a screening level of 0.001 mg/kg/day. The level is based on the ATSDR's intermediate oral Minimum Risk Level (MRLi)1. The MRLi is the screening level below which non-cancer health effects are unlikely to occur after an intermediate exposure period of 15-364 days. Safety and modifying factors have been incorporated into the MRLi to ensure that sensitive populations, such as pregnant women, nursing mothers, infants, and children are protected.
Because a suitable chronic NOAEL or LOAEL value for the MRL derivation could not be identified in the available literature 1, ATSDR has not derived a chronic duration MRL. ATSDR's chronic MRL is the counterpart of USEPA's reference dose (e.g., the proposed RfD value of 0.00025 mg/kg/day for toxaphene.)
The dose of PCC to a hypothetical angler (weighing on average 70-kg or approximately 154 pounds) who eats 30 grams of fish a day (one fish meal of 210 grams a week or an average of about one ounce per day) is estimated to be 0.002 milligrams per kilogram per day (mg/kg/day), assuming the fish fillet contained 3.9 ppm of PCC. But this estimated dose could be 10 times higher if historical data are taken into account for the dose estimation. This hypothetical angler is also expected to receive an estimated dose of 0.0003 mg/kg/day of PCC from surface soil if they ingest 100 mg of soil similar to the soil at Area 1, or at Hercules dock--which contains about 240 ppm of total PCC.
The combined dose of PCC from fish and soil ingestion is estimated to be 0.002 mg/kg/day. This dose exceeds ATSDR's screening level (i.e., intermediate oral Minimum Risk Level, or MRLi) of 0.001 mg/kg/day for non-cancer effects after short-term exposure, and it needs further evaluation. In a dose about 10 times higher, rat pups during their early development showed both inferior righting ability and retarded maturation in a swimming test. Behavior effects were also reported in the offspring of rats receiving a dose level as low as 0.05 mg/kg/day. No dose lower than 0.05 mg/kg/day of technical grade toxaphene was reported in this short-term animal study, and for rats the no observed adverse effect level of Toxaphene is unknown 40. Still, retarded maturation was also observed at dose level of 0.002 mg/kg/day in rats exposed to two toxaphene components, toxicant A and toxicant B 40. In view of the former high PCC levels and the limited data on current PCC levels in food fish, it is recommended that pregnant and lactating women avoid consuming a large quantity of seafood caught in this area. This precaution will protect the developing nervous systems of the fetus and infant from the potentially harmful effects of PCC.
Sufficient evidence has established that toxaphene can cause cancer in laboratory animals. When administered in the diet, technical-grade toxaphene increased the incidence of liver cancers in male and female mice, and thyroid cancers in male and female rats. But no adequate human data are available to evaluate the carcinogenicity of toxaphene. Only two human studies have evaluated the association between toxaphene exposure and the risk of anemia and chromosomal aberrations 20. USEPA has classified toxaphene as a probable human carcinogen. Three other national and international organizations have assigned similar classifications to toxaphene.
Given the estimated PCC dose of 0.002 mg/kg/day from soil and fish, the 70-kg angler is expected to receive a moderate increased risk of cancer (about 2 in 1,000) if exposed to this dose level for a lifetime. Yet this estimated risk only serves as a guide for risk management--it does not mean that cancer will occur. Among the many uncertainties with this estimate are:
- Composition of the weathered PCC in fish differs from that in technical-grade toxaphene, and the toxaphene adsorbed on soil can have different bioavailability than technical-grade toxaphene.
- The actual suite of PCC components in fish has not yet been tested for its toxicity in laboratory animals 42.
- Because very few reference standards are readily available in 1990s to determine the relative response of individual congeners or to match the profiles detected in fish, most estimates of toxaphene levels are semi-quantitative.
- The estimated concentrations of PCC in fish vary with the calculation procedure. The kinds of reference standards and the peaks selected to represent toxaphene affect the estimated concentrations of total PCC.
Contamination - Source Unknown
Mercury and PCBs
Mercury found in on-site fish did not exceed the Food and Drug Administration's (FDA) action level of 1.0 ppm. The state and USEPA recommended, however, based on contamination with polychlorinated biphenyls (PCBs) and mercury, no more than one meal per week of silver perch (yellowtail) caught south of Torras Causeway to Lanier Basin.
Arsenic levels of 3.3 ppm in on-site fish fall within the normal range of 4 to 5 ppm for shell fish and marine fish 43. Much of the arsenic present in fish and shellfish exists in an organic form (arsenobetaine) that is essentially nontoxic. That said, however, some of the arsenic in seafood is in an inorganic form. For example, a recent study in the Netherlands reported that inorganic arsenic comprised 0.1 to 41% of the total arsenic in seafood 44. Analyzing area fish for organic and inorganic arsenic will resolve the minor uncertainty on the potential contamination of food fish by inorganic arsenic.
ATSDR representatives spoke with 27 residents living near the Terry Creek site. Seven persons (about 26% of the 27 residents) reported that they, or their family members, had asthma or respiratory problems. Most residents did not think their respiratory problems were related to the contaminated dredge spoil. Other health complaints of one or more individuals included allergies, headaches, swollen joints (fibromyalgia of entire body), microvascular arteriosclerosis, arthritis, nonfunctioning thyroid, lupus, and stomach problems. A few mentioned lung cancer, which they attributed to smoking, and one had concerns about colon and brain cancers. An evaluation of these community concerns has been presented in the Community Health Concerns section.
Animal testing indicates the most sensitive non-cancer end point of toxaphene are developmental effects before and after birth 1. When pregnant rats were fed a diet contaminated with toxaphene, retarded swimming ability and inferior righting responses of their offspring were observed 40. But the exposed rats eventually attained normal swimming ability. Also, when the rats took a maze test at the age of 70 days, those previously exposed to PCC components had difficulty remembering the path leading to the food. Thus to avoid potential harm to the human fetus and infants and to protect developing systems, pregnant women and nursing mothers should avoid consuming large quantities of contaminated fish and, obviously, avoid ingesting contaminated soil. Exposure to toxaphene through contaminated fish and surface soils should also be minimized in infants and young children.
The Georgia Department of Human Resources (GDHR), Cancer Control Section prepared a report on "Mortality Rates for Selected Cancers" for the period 1988-1992. The mortality rates include age-adjusted rates using the 1970 United States population as a standard. The age-adjusted mortality rate for each individual county covered residents from 0-85 years of age. The report also documented mortality rates at county levels for the overall population. Mortality data at a smaller geographical level, such as zip code, is not currently available. In 1990, 4,837 persons lived within a 1-mile radius of the Terry Creek site, representing less than 8% of the total population (62,496 persons) in Glynn County.
The age-adjusted, annual mortality rate for all cancers in Glynn County was 190.8 per 100,000 persons in the overall population. This Glynn County rate is slightly above the rate of 175.9 in the state of Georgia and 179.8 in the United States. Among the nearby counties, the rate of 190.8 in Glynn County is within the range of the rates in other counties, e.g., 179.7 for Camden County to the south, 204.1 for McIntosh County to the north, and 177.3 for Brantley County to the west. Also, because the residents near this waste site comprise less than 8% of the Glynn County population, their health status should have only limited influence on Glynn County vital statistics.
The age-adjusted mortality rate for liver cancer in Glynn County was 3.3 per 100,000, while the rate was 2.9 for the state of Georgia and 3.0 for the U.S. But only 13 cases of liver cancer were reported in Glynn County during 1988-1992, and the rates, based as they are on less than 20 cases, might be unstable. The three other nearby counties reported only three cases and also have unstable rates. Camden had a rate of 3.6, McIntosh had 0, and Brantley 0. And because of their small populations, no cases of death from liver cancer would be expected in McIntosh and Brantley Counties.
The age-adjusted, annual mortality rate for lung cancer in Glynn County was 66.2 per 100,000. That was higher than the state rate of 54.3 and the U.S. rate of 52.5. Glynn County's lung cancer rate of 66.2 was comparable to the rates of nearby counties of 57.6 in Camden, 66.4 in McIntosh, and 61.9 in Brantley. The elevated lung cancer rate is common in this region. No studies were found regarding cases of lung cancer following toxaphene exposure.
The Georgia Department of Human Resources (GDHR), Division of Public Health also provided ATSDR with tables for the "Top Ten Causes of Death by Sex-Race Group" for Glynn County. The 1987-1996 data covered residents of various age groups. The GDHR also provided ATSDR with similar vital statistics: "Leading Causes of Death, 1991," published by the Georgia County Guide-the University of Georgia-Athens. Mortality rates of total cancers and lung cancer have been evaluated in this section. Mortality rates for noncancer diseases (e.g., heart disease, stroke) in Glynn County will be compared to state and national rates once the reference data become available. ATSDR will evaluate other health outcome data when the new data become available, if appropriate.
- The concentration of PCC in environmental samples, such as sediment and fish, has decreased since 1972, when PCC in effluent from the Hercules manufacturing plant was restricted. Generally, PCC in seafood has decreased from 10s of ppm to less than 5 ppm (based on available data before 1998 for estimated concentrations in limited types of seafood). But recent (June 2000) data indicated that PCC levels in food fish remained high. For rough fish, the average PCC levels in killifish fell from 62 ppm in 1970s to 7 (1.9- 27) ppm in 1997.
- The most likely pathway for human exposure at the Terry Creek /Hercules site is through seafood. Consumption of contaminated seafood is a concern expressed by residents consuming fish caught in, or near, the Dupree and Terry Creek areas. More information on quantitative estimations of recent PCC residues in seafood from the Terry Creek area is needed, as well as more information on the toxicologic meaning of such data. Based on these data gaps, ATSDR categorizes this site as an indeterminate public health hazard. More information on quantitative and qualitative estimations of recent PCC residues in seafood from the Terry Creek area and on the toxicological meaning of such information will be useful. Potential for human exposure is limited at levels that would be of health concern in the other pathways such as soil, sediment, produce from gardens, or water.
- Approximately 26% of the of the local residents who participated in the limited sampling reported that they or their family members have asthma. Health statistics with respect to this, as well as environmental data, need further investigation.
- ATSDR will re-evaluate the health hazard at this site when new data become available. The recent fish data prepared on 6/16/2000 by Skidaway lab were published in 2001 in peer-reviewed, open literature 31. These new data will be assessed in a health consultation scheduled for release after this health assessment.
- Based on data gaps such as uncertainty in the PCC levels of in fish, ATSDR recommends limiting exposure to contaminated seafood from Dupree and Terry Creeks. It is further recommended that the Georgia Environmental Protection Division (GA EPD) continue evaluation of seafood and determine whether further limits or restrictions are warranted. People eating fish from nearby areas can lower their risk of ingesting organic contaminants such as PCC and PCBs by removing fatty tissue before cooking, as well as by eating small (younger) fish.
- Due to interference from other chlorinated compounds in the fish samples and the uncertainty they cause in the toxaphene estimates, sensitive and specific methods, such as electron capture negative ion mass spectrometry (GC-ECNIMS) are recommended for the evaluation of PCC in fish and sediment. GA EPD and USEPA will employ such methods.
- Additional seafood sampling is needed to help assure residents that fish caught in unrestricted areas near the site are safe. In addition to further seafood samples from Terry and Dupree Creeks, additional sampling in the Back River, upstream of its confluence with Terry Creek (near Riverside Development) is recommended. The following contaminants should be analyzed in seafood: PCC, heavy metals--including mercury--and PCBs.
- It is recommended that those residential yards that receive or have received silty run off from flooding drainage ditches on the Hercules plant site be sampled for PCC.
- Garden soils should be analyzed for PCC if contaminated dredge spoil or other major sources of PCC contamination are suspected.
- The community well at the Terry Creek Mobile Home Park (TCMHP) should be tested with a minimum detection limit below the MCL of 3 ppb to assure residents that their drinking water is safe. ATSDR needs further information (such as the depth of the well and any sampling data) regarding the community well at the TCMHP.
- ATSDR has requested, and should obtain, all future or additional data for Terry Creek that is currently available.
- Based on the results of the air toxics data set collected as part of the Brunswick/Glynn County Initiative, ATSDR recommends further evaluation of air quality in the general area of Brunswick, particularly with respect to potential carcinogens and respiratory irritants.
Major purposes of a public health assessment include the identification of actions to protect public health, the evaluation of whether exposure is occurring or could occur, and the determination of site-related health effects. The following public health actions have been specified.
Completed Public Health Actions
Because of the cleanup of toxaphene contaminated sediments, the Georgia Environmental Protection Division, Coastal Resources Division, and the U.S. Environmental Protection Agency recommend against fishing or swimming in all of Dupree Creek and Terry Creek north of Torras Causeway to 2 miles west of its confluence with the Back River. Additionally, they recommend no more than one meal per week of silver perch (yellowtail) caught south of Torras Causeway to Lanier Basin, based on contamination with polychlorinated biphenyls (PCBs) and mercury from unknown sources. Additionally, clams, mussels, and oysters in these waters have been deemed not edible, based on the National Shellfish Sanitation Program standards (the reasons for this ban are unrelated to the Terry Creek Dredge Spoil Site).
Ongoing Public Health Actions
The recommendations in the Recommendation section should be considered as public health actions. ATSDR will work with state and federal agencies to complete these recommendations. USEPA is currently working on sediment removal plans and site remediation. The GA EPD is conducting further air monitoring and evaluation of existing air data for the Brunswick area. As one of its potential research topics, ATSDR has selected the toxicity study of PCC residues in local fish. GA EPD is analyzing a new batch of fish samples for toxaphene, and will update the fish consumption guidance in the spring of 2003.
Dr. Shan-Ching Tsai (Site lead)
Superfund Site Assessment Branch
Division of Health Assessment and Consultation
Laura H. Frazier
Environmental Health Scientist
Federal Facilities Assessment Branch
Division of Health Assessment and Consultation
Diane M. Drew, RN, MPA
Health Education Specialist
Health Education Branch
Division of Health Education and Promotion
ATSDR REGIONAL REPRESENTATIVE
ATSDR Region IV
- Agency for Toxic Substances and Disease Registry. Toxicological profile for toxaphene. Atlanta: US Department of Health and Human Services; August 1996.
- Hicks HE. Letter to R.S. Howard, Jr., Executive Secretary, State Water Quality Control Board concerning toxaphene pollution abatement; December 21, 1970.
- US Environmental Protection Agency. HRS documentation record, Terry Creek Dredge Spoil Area/Hercules Outfall; January 31, 1997.
- Boy W. Department of the Army, Savannah District, Corps of Engineers. Letter to J. McKeown, USEPA, regarding Hercules, Inc. dredge spoil disposal; March 3, 1994.
- Reimold RJ. Toxaphene interactions in estuarine ecosystems. University of Georgia, Marine Institute, Sapelo Island, 1974. Technical Report Series Number 74-6.
- Horton KT. Letter to Georgia Environmental Protection Division, Water Quality Control Section concerning notice of noncompliance with NPDES Permit #GA0003735; January 19, 1978.
- Hoffman GR. Letter to Bozeman JR, Assistant Chief, Marsh and Beach Section, Georgia Department of Natural Resources concerning Dupree Creek dredging and plant history; January 5, 1987.
- Agency for Toxic Substances and Disease Registry. Record of Activity on surface soil from residential areas adjacent to the Hercules facility in Brunswick, Georgia. Atlanta: US Department of Health and Human Services; September 14, 1994.
- National Oceanic and Atmospheric Administration. Brunswick/Glynn County Community Based Environmental Protection Project Document Catalog. HAZMAT Report 96-10. 52 pages. Atlanta: U.S. Environmental Protection Agency (Waste Division); 1996.
- Warren RC. Letter to L. Barr, ATSDR concerning how to define Environmental Justice Sites; June 8, 1998.
- Hill RA. Disposition form and attachments to OP-PN (Garrett); February 29, 1988.
- McCall RS. Letter and enclosure to C. Blair, ATSDR concerning a door-to-door survey and inquiry on resident fishing; August 21, 1997.
- Georgia Department of Natural Resources Environmental Protection Division and Wildlife Resources Division. Terry and Dupree Creek--information for fishing regulations and consumption guidelines booklet; 1998.
- Black & Veatch Special Projects Corp. Expanded site inspection, Terry Creek Dredge Spoil Area, Brunswick, Glynn County, Georgia. Prepared for: USEPA Region 4; July 12, 1996.
- ATEC Associates, Inc. Best management practices plan, Hercules, Inc. May 1993.
- Kidd KA, Eamer JE, and Muir DCG. Spatial variability of chlorinated bornanes (Toxaphene) in fish from Yukon lakes. Chemosphere 1993; 27:1975-86.
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- US Environmental Protection Agency. Toxic chemical release inventory. Washington, DC: National Library of Medicine; p.1987-95.
- Georgia Department of Natural Resources, Environmental Protection Division. 1996 Glynn County Initiative: Air toxics data set, ground level measurements. Atlanta, GA; 1996
- National Toxicology Program. 2001. 9th Report on carcinogens. RTP, NC. US Department of Health and Human Services, Public Health Service, National Toxicology Program. Revised January 2001.
- US Environmental Protection Agency. Ambient water quality criteria for toxaphene. USEPA 440/5-86-006. Washington, DC; 1986.
- Durant CJ and Reimold RJ. Effects of estuarine dredging of toxaphene-contaminated sediments in Terry Creek, Brunswick, Georgia 1971. Pestic Monit J 1972; 6:94-96.
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- Butler PA. Residues in fish, wildlife, and estuaries, organochlorine residues in estuarine mollusks, 1965-1972--National Pesticide Monitoring Program. Pestic Monit J 1973; 6(4):238-362.
- US Environmental Protection Agency, Science and Ecosystem Support Division, Ecological Assessment Branch. Terry Creek ecological screening evaluation, Brunswick, Georgia; July 1997.
- Tetra Tech EM, Inc. Analysis of toxaphene residues in sediment and fundulus from Terry/Dupree Creek. Final Report--Phase I, submitted by K.A. Maruya and S.G. Wakeham from Skidaway Institute of Oceanography and L. Francendese from USUSEPA, Atlanta, GA; July 31, 1998.
- Law Engineering and Environmental Services, Inc. Final report for the collection and analysis of fish and crab tissue from Terry and Dupree Creeks, Brunswick, Georgia. Prepared for Hercules, Inc., Resins Division; April 10, 1996.
- Georgia Department of Natural Resources, Environmental Protection Division. Laboratory Reports on fish and shellfish from the Terry and Dupree Creeks, Brunswick, Georgia (Draft release); 1998.
- Hercules, Inc. Toxaphene pollution abatement. November 6, 1970.
- Reimold RJ and Durant CJ. Survey of toxaphene levels in Georgia Estuaries. Georgia Marine Science Center, University System of Georgia. Technical Report Series, Number 72-2. Skidaway Island, Georgia; February 1972.
- Maruya K, Walters TL, and Manning R. Residues of toxaphene in fin- and shellfish from Terry/Dupree Creek, Georgia, USA. Estuaries 2001;24:585-596.
- Carlin FJ, Jr and Hoffman JM. The effect on calculated results of analysis caused by the variability among toxaphene reference standards. Organohalogen Compounds 1997; 33:70-75.
- Eastern Research Group. Toxaphene levels in fish:GC-ECD data review, task order number 0901-04, Contract No. 205-95-0901, prepared by Mahmoud A. Saleh, North Texas University, TX. May 1998.
- Maruya KA and Lee RF. Arochlor 1268 and toxaphene in fish from a southern U.S. estuary. Environ Sci Technol 1998;32:1069-75.
- Newfield, Inc. Statistical analysis of off-site toxaphene data near Hercules Brunswick facility. Prepared for Hercules Incorporated; July 18, 1996.
- Agency for Toxic Substances and Disease Registry. Record of activity on surface soil analytical data from school playgrounds and city and county parks in Brunswick, Georgia. Requested by USEPA region 4. Atlanta: US Department of Health and Human Services; October 2, 1996.
- Atlanta Testing & Engineering. Report of additional environmental investigative services--Burroughs-Molette & Goodyear Elementary Schools, Brunswick, Georgia. Prepared for: Glynn County, Georgia. January 17, 1997.
- GeoSyntec Consultations. Status report, revision 0, Terry Creek Site, Brunswick, Georgia. Prepared for Hercules, Incorporated. December 1998.
- Howard PH.ed. Handbook of environmental fate and exposure data for organic chemicals. Vol. 3, pesticides. Chelsea, MI: Lewis Publishers, 1991.
- Olson KL, Matsumura F and Boush GM. Behavioral effects on juvenile rats from perinatal exposure to low levels of toxaphene, and its toxic components, toxicant A, and toxicant B. Arch Environ Contam Toxicol 1980; 9:247-57.
- Agency for Toxic Substances and Disease Registry. Public health assessment guidance manual. Atlanta: US Department of Health and Human Services; March 1992.
- Lockhart WL and Saleh MA et al. Report of working group on toxicology of chlorinated bornane compounds. Chemosphere 1993;27(10):1841-48.
- Agency for Toxic Substances and Disease Registry. Toxicological profile for arsenic (update). Atlanta: US Department of Health and Human Services; September 2000.
- Vaessen HA, Van Ooik A. Speciation of arsenic in Dutch total diets: methodology and results. Z Lebensm Unters Forsh 1989;189:232-35.
- Black & Veatch Special Projects Corp. Field study plan, expanded site inspection, Terry Creek Dredge Spoil Area, Brunswick, Glynn County, Georgia. Prepared for USEPA Region 4; September 5, 1995.
- Muir DCG and de Boer J. Toxaphene: analytical chemistry. Chemosphere 1993;27 (10):1827-34.
- Francesconi KA and Edmonds JS. Biotransformation of arsenic in the marine environment. In: Nriagu O, editor. Arsenic in the environment, Part 1: cycling and characterization. New York: John Wiley & Sons, Inc., 1994.
- Reed DL. Memorandum to R. Manning and TV Jackson regarding explanation of clutter in fin fish samples in the area of the Hercules facility. January 23, 1998.
- Lee RF, Maruya K, Francendese L. Final report: DNA strand damage, embryotoxicity and toxaphene concentrations in grass shrimp palaemonetes pugio from stations in Terry/Dupree Creek, Brunswick, Georgia. Submitted to PRC Environment Management Inc. (Tetra EM Inc.), October 24, 1998.