PUBLIC HEALTH ASSESSMENT
CALLAWAY AND SON DRUM SERVICE
LAKE ALFRED, POLK COUNTY, FLORIDA
From 1977 to 1991, Callaway and Son Drum Service in Lake Alfred cleaned and recycled 55-gallon oil and citrus drums. Between 1984 and 1994, contractors for the Environmental Protection Agency (EPA) and Florida Department of Environmental Regulation (FDER) reported contamination of both soil and groundwater with heavy metals, solvents, pesticides and gasoline components. FDER determined the solvent and pesticide contamination was due to Callaway and Son operations. The heavy metal and gasoline contamination are thought to be due to the neighboring sewage treatment plant and a gasoline spill, respectively. The Florida Department of Health (FDOH), Bureau of Environmental Toxicology and the Agency for Toxic Substances and Disease Registry conducted this Public Health Assessment in response to the EPA proposing this site to the National Priorities List.
FDOH classifies this site an "indeterminant public health hazard" because the soil and groundwater contamination have not been adequately characterized. Specifically, the horizontal and vertical extent of the contamination has not been characterized. Shallow aquifer samples were not taken south of the site. In addition, many Floridan aquifer private wells have been identified in the surrounding area. However, only one on-site Floridan aquifer sample has been collected. Limited off-site soil samples have been collected.
Contamination of the soil with metals was highest in the area of sandblasting and painting on the site. FDER and EPA detected arsenic concentrations that if ingested could cause a mild increase in the risk of bladder, skin and kidney cancer. On-site soil also contained chromium and lead at concentrations that could cause mild effects on the blood, liver, heart, neurological system, reproductive system and skin. Investigators detected no metal contamination in off-site soil and no pesticides or solvents in either on-site or off-site soil.
Shallow, on-site groundwater was contaminated with solvents, pesticides and metals. Because of the low concentrations detected, FDOH does not anticipate the solvents and pesticides to cause illness or cancer. However, arsenic, barium, cadmium, chromium, lead and nickel were detected at concentrations that, if ingested, could cause abdominal pain, numbness, anemia, heart, liver and kidney disruptions, and dermatitis. These metals were also detected in similar concentrations off-site to the north. The Floridan aquifer wells that were tested on- and off-site showed no contamination.
This Public Health Assessment is based on a limited number of samples. The lateral extent of contamination is not known since no groundwater samples were collected immediately south of the site, in the probable direction of groundwater flow. Also, no soil samples were taken south of the site, where trespassers would likely enter the property. To detect potential exposures, Polk County Health Department has agreed to sample the private and public supply wells that are likely to be in the path of contaminant movement (i.e., south-southwest). Furthermore, FDOH recommends that environmental agencies restrict access to the site and collect more soil and groundwater samples to better characterize the lateral and vertical extent of contamination. In addition, FDOH recommends that environmental agencies collect sediment samples from the ditch that drains surface water from this site.
The Florida Department of Health (FDOH), Bureau of Environmental Toxicology conducted this Public Health Assessment when the Environmental Protection Agency (EPA) proposed the Callaway and Son Drum Service site to the National Priorities List (NPL). In this report, FDOH assesses the past, current and future public health threats from exposure to chemicals in the environment at and around the Callaway and Son Drum Service hazardous waste site. FDOH estimates which groups of people may be at risk under past, current and potential future conditions. FDOH estimates if these exposures are likely to be causing illness now, or may likely cause illness in the future. In this Public Health Assessment, FDOH, in cooperation with the Agency for the Toxic Substances and Disease Registry (ATSDR), evaluates the public health significance of the Callaway and Son Drum Service site. ATSDR, in Atlanta, GA, is a federal agency within the U.S. Department of Health and Human Services. Financial support for this project is provided entirely by the ATSDR.
The Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA) authorizes the ATSDR to conduct Public Health Assessments of hazardous waste sites. Specifically, FDOH will determine whether illness is possible from exposure to contaminants from the site and recommends actions to reduce or prevent these exposures and therefore, the illnesses.
Callaway and Son Drum Service is at 890 East Lake Drive in Lake Alfred, Polk County, Florida (Figures 1 and 2, Appendix A). The northern border of the site is a rail line which separates the site from a University of Florida Experiment Station. A nursery is southwest of the site and the sewage treatment plant is due west. A cemetery and an apartment complex are adjacent east of the site. Of potential concern for past exposures was the presence of a playground at this apartment complex. This playground is no longer in existence. The site occupies approximately 9.5 acres and consists of a drum cleaning area, a sandblasting and painting area, and a drum storage area (Figure 3, Appendix A). The vacant office building is on the southern portion of the site. A large pond/wetland is in the central and eastern areas of the site. Surface water from the site drains via a ditch towards Lake Haines approximately 1000 feet south of the site. This ditch enters the site in the northeastern corner, runs down the east side of the pond/wetland and exits the site at the southwest corner (Figure 3, Appendix A).
Callaway and Son Drum Service was owned by Mr. Ronald Callaway and began operations in 1977, but has been inactive since 1991. Callaway and Son Drum Service cleaned and recycled 55-gallon citrus and oil drums. The drums were cleaned with a resin solution and then rinsed in a 600-gallon fresh water tank. The specific contents of the resin solution are given in the Groundwater Investigation Report (FDER, 1984). In general, the resin solution was a mix of caustic alkalies, a glycol ether solvent and a detergent. The facility processed about 20 drums per day, 5 days a week, except during the citrus season, when Callaway and Son Drum Service handled up to 500 drums per day (Jacobs Engineering Group, Inc., 1992). The rinse tank was drained every two weeks into the pond/wetland area on the eastern portion of the property (Black and Veatch Waste Science Corp., 1994). Currently, no business operations exist on-site.
This site first came to the attention of the Florida Department of Environmental Regulation (FDER) in 1984, when the owner of the site submitted an application to operate an industrial wastewater treatment and disposal system. FDER sampled and analyzed the on-site groundwater, surface water and private well water from on the Callaway property and in the surrounding areas. FDER found no contamination of off-site private wells or the on-site, deep well. However, the shallow aquifer groundwater and surface water samples showed contamination with vinyl chloride, 1,2-dichloroethylene and lead (FDER, 1984).
In 1985, a gasoline pipeline owned by Central Florida Pipeline ruptured, spilling approximately 40,000 gallons of unleaded fuel on the eastern portion of the Callaway property. Central Florida Pipeline performed a clean-up of the spilled fuel. In 1986, FDER sampled the groundwater from the property and confirmed the presence of lead, but also detected chromium, benzene, ethylbenzene, methyl-t-butyl ether and toluene (FDER, 1986). This report concluded that the source of the chromium and lead on the site was not the gasoline spill nor the operations on-site, but was the sewage treatment plant to the west.
In 1992, contractors for the Florida Department of Environmental Protection (FDEP), formerly FDER, further detailed the nature of contamination on the site (Jacobs Engineering Group, Inc., 1992). Surface soil samples from the drum cleaning area contained various heavy metals, including arsenic, chromium and lead. Groundwater from the shallow aquifer contained both heavy metals and chlorinated solvents, including vinyl chloride, dichloroethylene, trichloroethylene and tetrachloroethylene. In 1994, EPA contractors collected additional soil, sediment and groundwater samples to further characterize the nature and extent of contamination (Black and Veatch Waste Science Corp., 1994). This study reported a similar profile of contaminants as seen in the 1992 report. In the preparation of this Public Health Assessment, FDOH pooled and evaluated all of the data presented in the EPA and FDER reports (FDER, 1984; 1986; Jacobs Engineering Group, Inc. 1992; Black and Veatch Waste Sciences Corp., 1994).
On October 19, 1999, Davis Daiker and Randy Merchant of the FDOH, Bureau of Environmental Toxicology visited the site. They observed the Callaway and Son site on the north side of U.S. Highway 17 and also toured the surrounding areas. The only entrance to the property is from the south. The office building on the southeast side of the site is still present although it is in disrepair. The majority of the site is unpaved and covered with heavy brush and tall grass. The site appears abandoned and no signs of trespass were observed. With the exception of the south entrance to the site, the site is secured with an intact fence. Unauthorized access is possible since the southern border is open. Mr. Daiker and Mr. Merchant observed the mobile home developments south of the site and on a drive-through inspection, observed several private wells and one public supply well within the area south of the site. They were told by an associate of one of the parks that the residents receive their drinking water from a public supply well.
3.3.1 Demographics - Based on 1990 census information, approximately 2,300 residents (Table 10, Appendix B), approximately 550 under the age of 17, live within one mile of the site. Of this population, 78% were white, 19% were black, and 3% were Hispanic or from other racial/ethnic groups.
3.3.2 Land Use - Land use in this area is a mix of commercial and residential. The apartments to the east are the nearest residential buildings. Across East Lake Drive to the southeast but north of Lake Haines is a large mobile home community. To the southwest, there is a residential neighborhood with many homes within one-half of a mile of the site. Residential properties are also to northwest of the site. North, west and northeast of the site are predominantly commercial or nonresidential establishments. Three schools are within one mile of the site. An elementary school and a career center are less than 1 mile southwest of the site and a third school is 0.3 miles northwest of the site.
3.3.3 Natural Resource Use - This region of Florida has both the surficial and the Floridan aquifers, which are separated by a semi-permeable, intermediate layer. The surficial aquifer begins two to five feet below the surface and is 50 to 75 feet thick (FDER, 1992). The intermediate clay layer lies below the surficial aquifer and ranges 15 to 20 feet thick. This clay layer is considered semi-permeable because of the presence of sinkholes, which allow for recharge of the Floridan aquifer (FDER, 1984; 1986). Therefore, contaminants in the surficial aquifer can leach into the Floridan aquifer. The Floridan aquifer lies underneath the intermediate layer and continues several hundred feet deep. Because of the poor water quality in the surficial aquifer, the Floridan aquifer is the major source of potable water in this region of Florida. FDEP and EPA identified at least two public supply wells within one mile of the site, which service approximately 275 people. FDOH, with the help of the Southwest Florida Water Management District, has identified several irrigation and private wells within 1 mile of the site. In addition to these public and private wells, the Lake Alfred municipal wells, which supply much of the area with drinking water, are just over one mile west of the site. FDOH does not anticipate the groundwater contamination to move in the direction of the municipal wells. The potable wells of greatest concern are located south-southwest of the site in the direction that the groundwater in the Floridan and surficial aquifer flows.
Uncertainties are inherent in the public health assessment process. These uncertainties fall into four categories: 1) science is never 100% certain, 2) the inexactness of the risk assessment process, 3) the incompleteness of the information collected thus far, and 4) differences in opinion as to the implications of the information (NJDEP, 1990). These uncertainties are addressed in Public Health Assessments by using worst-case assumptions when estimating or interpreting health risks. They also incorporate uncertainties by using wide safety margins when setting health-related threshold values. The assumptions, interpretations, and recommendations made throughout this Public Health Assessment err in the direction of protecting public health.
We used the following ATSDR standard comparison values (ATSDR 1992a; 1999a), in order of priority, to select potential contaminants of concern at this site:
- CREG - Cancer Risk Evaluation Guide - calculated from the EPA's cancer slope factor and is the contaminant concentration estimated to result in no more than one excess cancer per one million persons exposed over a lifetime.
- EMEG - Environmental Media Evaluation Guide - derived from the ATSDR's Minimal Risk Level (MRL) using standard exposure assumptions, such as ingestion of two liters of water per day and body weight of 70 kg for adults. MRLs are estimates of daily human exposure to a chemical generally for a year or longer likely to be without an appreciable risk of noncancerous illnesses.
- RMEG - Reference Dose Media Evaluation Guide - derived from the EPA's Reference Dose (RfD) using standard exposure assumptions. RfDs are estimates of daily human exposure to a chemical likely to be without an appreciable risk of noncancerous illness, generally for a year or longer.
- LTHA - Lifetime Health Advisory - EPA's estimate of the concentration of a drinking-water contaminant at which illnesses are not expected to occur over lifetime exposure. LTHA's provide a safety margin to protect sensitive members of the population.
- SCTL or GWCTL - Soil Clean-up Target Level or Groundwater Clean-up Target Level as determined by the Florida Department of Environmental Protection. This value is used only when no values exist for #1 through #4.
We use ATSDR standard comparison values to select chemicals for further consideration, not for determining the possibility of illness. Identification of a contaminant of concern (COC) in this section does not mean that exposure will cause illness. Identification of COCs serves to narrow the focus of the Public Health Assessment to those contaminants that are most important to public health. When we select a COC in one medium (i.e., soil), we report that contaminant in all other media (i.e., groundwater). We evaluate the COC in subsequent sections and estimate whether exposure is likely to cause illness. All available documents were evaluated when we identified the contaminants of concern. The environmental data is presented in Tables 1 through 8 (Appendix B).
4.1.1 On-Site Contamination - In a series of site investigations, EPA and FDER contractors sampled the groundwater, surface soil (0-6"), and sediment from the pond/wetland. These samples were then analyzed for chemical contaminants. For this Public Health Assessment, "on-site" refers to the area within the Callaway and Son property boundaries as shown in Figures 3 and 4 (Appendix A).
Groundwater samples taken from the western portion of the site contained both inorganic and organic materials (Tables 1 and 2, Appendix B). Groundwater samples taken from the area of drum cleaning (Figures 3 and 4) were contaminated with tetrachloroethylene, trichloroethylene and dichloroethylene. Gamma-chlordane, a pesticide, and 4,4'-DDE, a breakdown product of DDT, were detected in the same area at concentrations above their respective comparison values and are therefore, considered COCs (Table 1, Appendix B). This organic contamination is a public health concern since these solvents travel very well in groundwater and could, therefore, migrate off-site. Inorganic/metal contamination was highest in the areas of sandblasting and painting activities (Figures 3 and 4, Appendix A). EPA detected aluminum, arsenic, barium, cadmium, chromium, lead, thallium and vanadium in the groundwater at concentrations that exceeded the respective comparison values. Therefore, we considered each of these metals a COC (Table 2, Appendix B). The maximum concentrations, the frequency of detection, and the comparison values used for each COC are given in Tables 1 and 2 (Appendix B). The limited number of on-site groundwater samples served to identify the contaminants present but does not provide insight into the direction of contaminant movement. Of special importance is that FDEP found no contamination in the on-site supply well, which is drilled into the Floridan aquifer (DW-8 [Figure 4, Appendix A]) (FDER, 1984). For the purpose of this Public Health Assessment, on-site groundwater contamination has not been adequately characterized.
On-site surface soil, like the groundwater, was also contaminated with metals. Arsenic, chromium and lead were detected in soil samples taken from the western side of the property, where the cleaning, sandblasting and painting activities occurred. The organic contaminants (i.e., solvents, pesticides) were not present in soil at concentrations above the ATSDR screening levels. Therefore, only the metals listed above were considered COCs for on-site soil. Tables 3 and 4 (Appendix B) list the COCs for on-site soil and also provide the maximum concentrations at which they were detected. The limited number of on-site soil samples identified the COCs but does not clearly delineate the extent of contamination or the public health threat. In addition, no soil samples were taken from the southern portion of the site, where trespasser access is simple. For the purpose of this Public Health Assessment, on-site soil contamination has not been adequately characterized.
Of the four sediment samples taken from the pond/wetland, only one contained any of the identified COCs at a concentration above the ATSDR screening value. This sample was taken from the sediment in the southwestern portion of the on-site pond/wetland (Figure 4, Appendix A) and contained arsenic. No organic contaminants were detected in any of the sediment samples. For the purpose of this Public Health Assessment, contamination of the sediment in the pond/wetland has been adequately characterized.
4.1.2 Off-Site Contamination - EPA and FDER contractors also sampled groundwater, soil and surface water from areas off of the Callaway property. The purpose of these samples was to further define the areal extent of contamination and to provide a background concentration of the contaminants. A background concentration is the level of a chemical or metal that is likely to be present in the soil or groundwater that is not due to any spill, accident or release. This is the concentration that can "naturally" be found in the water or soil. Background concentrations help in determining if a hazardous waste site has impacted the areas surrounding it. FDOH uses the available data from these off-site samples to aid in determining whether the contamination was confined to the site. For this Public Health Assessment, "off-site" refers to the area surrounding the Callaway and Son property boundaries as shown in Figures 2 and 3 (Appendix A).
EPA and FDER contractors drilled several off-site shallow monitoring wells and sampled from several currently used potable wells south-southeast of the site. On average the shallow monitoring wells were screened between 10 and 15 feet in the surficial aquifer. One of the shallow monitoring wells was drilled north of the property and the other was drilled near the cemetery to the northeast (Figure 4, Appendix A). The only organic chemical detected in off-site groundwater was the pesticide gamma-chlordane (Table 5, Appendix B). However, off-site groundwater contained aluminum, arsenic, barium, cadmium, chromium, lead, mercury, nickel, selenium, thallium, and vanadium (Table 6, Appendix B) at concentrations above their respective comparison level. Groundwater from the private or public supply wells contained none of the COCs. Because of the small number of samples and the absence of monitoring wells south of the site, the direction of contaminant movement is not known. For the purpose of this Public Health Assessment, off-site groundwater has not been adequately characterized.
Of the three off-site soil samples reported in the site investigations, two were taken from the playground area east of the site and the third was taken outside the northeast corner of the site. The only sample showing any evidence of contamination was the soil sample from the playground, which contained an amount of arsenic that is only slightly higher than the ATSDR comparison value. Contamination with organic materials (i.e., solvents, pesticides) was not present in any of these samples. Two off-site surface water samples were taken from the drainage ditch. One of these samples was taken where the ditch enters the site and the other was taken where the ditch exits the site. Neither of these samples showed any contamination. Because of the importance of this ditch in regards to human exposure, FDOH concludes that the ditch has not been adequately characterized.
This Public Health Assessment is based on the data presented in the Groundwater Investigation (FDER, 1984), Lake Alfred Fuel Spill, Groundwater Investigation (FDER, 1986), Phase II Site Inspection (Jacobs Engineering Group, Inc., 1992) and the Expanded Site Inspection (Black and Veatch Waste Science Corp., 1994). Since the referenced data were gathered by consultants overseen by governmental agencies and the data were analyzed in accredited contract laboratories with proper handling and analysis procedures, we assume the data are valid. We assumed consultants who collected and analyzed these samples followed adequate quality assurance and quality control measures concerning chain-of-custody, laboratory procedures, and data reporting. The completeness and reliability of the referenced information determine the validity of the analyses and conclusions drawn in this Public Health Assessment. Data qualifiers, if present, are defined at the bottom of each table.
During the October 19, 1999 site visit, Mr. Daiker and Mr. Merchant observed the damaged building on-site, which could be a physical hazard to trespassers.
To estimate whether nearby residents have been exposed to contaminants migrating from the site, we evaluated the environmental and human components of contaminant exposure pathways. Exposure pathways consist of five elements: a source of contamination (e.g., chemical spill), an environmental medium (e.g., groundwater), a point of exposure (e.g., tap water), a route of human exposure (e.g., oral), and a receptor population (e.g., area residents).
We eliminate an exposure pathway if at least one of the five elements is missing and will never be present. Exposure pathways that we do not eliminate are either completed or potential. With completed pathways, all five elements exist and exposure to a contaminant has occurred, is occurring, or will occur. A pathway is classified as potential if at least one of the five elements is missing, but may be present in the future. For both complete and potential pathways, an estimation of the likely dose of each COC is calculated and this dose is used to perform a toxicological evaluation.
4.4.2 Potential Exposure Pathways - All of the potential exposure pathways are shown in Table 9 (Appendix B). The most likely potential exposure pathway is the consumption or use of groundwater by the residents living south of the site. We classify this pathway as potential because we have not identified a point of exposure. In the 1984 Groundwater Investigation, FDER tested several nearby potable wells and found no contamination. Polk County Health Department (PCHD) tested the well at one of the mobile home villages in 1994 and again in 1997 and found no contamination. Testing of the area public supply wells by PCHD is scheduled for the year 2000. PCHD does not routinely test private wells, so the status of the private wells to the southwest is not known.
A less likely but important potential pathway is the possible future consumption and use of on-site groundwater by future on-site residents. This pathway is missing a point of exposure, since no potable well exists on site. In addition, no receptor population exists on-site. If the land use were to change to residential and a potable well was drilled on-site, this pathway could be considered complete.
The final potential pathway is the exposure to contaminated soil on-site. Although there were no signs of trespass on site visit, trespassers could have been exposed in the past present and future to contaminated soil. In addition, if the land use were to change to residential, future residents could also be exposed to contaminated soil on-site. Due to the presence of the sewage treatment plant due west of the site, it is unlikely that the land use at this site would change to residential but, in the interest of public health, this pathway is examined. In Table 10, we estimate the total population potentially exposed.
4.5 Public Health Implications - In this section, we calculate the dose of a chemical which both adults and children could potentially receive by all likely routes of exposure. We then review the toxicological profile for each COC and determine if the estimated dose could cause illness. For this site, we calculated potential doses from exposure to on-site and off-site groundwater and on-site soil (Tables 11 through 15, Appendix B).
4.5.1 Toxicological Evaluation - In this section, we discuss illnesses that could occur following exposure to COCs at this site. To evaluate the risks of illness, the ATSDR has developed Minimal Risk Levels (MRLs) for contaminants commonly found at hazardous waste sites. A MRL is a conservative estimate of daily human exposure to a contaminant below which noncancerous illnesses are unlikely to occur. The calculation of the MRL is based on animal and human studies, when available. It is calculated very conservatively because the goal of the MRL is to protect public health. MRLs exist for each route of exposure, such as ingestion and inhalation, and for different lengths of exposure, such as acute (less than 14 days), intermediate (15 to 364 days), and chronic (greater than 365 days). The ATSDR presents these MRLs in Toxicological Profiles. Toxicological Profiles are chemical-specific and provide information on the health effects, environmental transport, human exposure, and regulatory status of a specific chemical.
To apply the MRL, we estimate the daily dose for each of the COCs using standard exposure parameter estimates (i.e., average volume of water consumed per day, average shower time, etc). Using these, we estimate the number of milligrams of contaminant ingested per day (mg/day) and then divide by the average human body weight. The dose is expressed as the number of milligrams of chemical per kilogram of body weight per day (mg/kg/day). In calculating the potential dose, we assume people are exposed to the maximum concentration detected for each contaminant in each medium. In Tables 11 through 15 (Appendix B), we summarize the estimated dose for each contaminant for each exposure pathway using the maximum COC concentration. In Tables 11-15 (Appendix B), a shaded cell indicates that the estimated dose exceeds the MRL. Since MRLs are conservative to protect health, a dose above the MRL does not necessarily mean that it will cause illness.
The exposure parameters for each exposure scenario are given below the tables. The values used are standard values for this type of analysis (EPA, 1991; 1997). For groundwater, we estimated the dose of chemical that could be ingested from drinking, absorbed through the skin during showering, and the air concentration that could be inhaled during showering. For soil exposures, we estimated the dose from incidental ingestion of soil and the dose from breathing contaminated dust.
18.104.22.168 Gamma-chlordane, chlorophenol, cresol, 4,4'-DDE, 1,2-dichloroethylene, tetrachloroethylene, and trichloroethylene- None of these organic compounds were detected at high enough concentrations in soil to deliver a dose that would exceed the respective MRL. Therefore, exposure to these chemicals in soil is unlikely to cause illness.
These contaminants were also not detected in groundwater, either on-site or off-site, at high enough concentrations to deliver an oral dose that would exceed the oral MRL (Tables 11 and 14, Appendix B). The future use of on-site groundwater for showering, however, may generate an air concentration of dichloroethylene, tetrachloroethylene and trichloroethylene that exceeds the respective inhalation MRLs. However, we do not anticipate any illness from these air concentrations because of (1) the conservative nature in which the MRLs are calculated, (2) the brief exposure time during showering, and (3) shower use of on-site groundwater could only occur if a private well was drilled on-site. Therefore, noncancerous illnesses are not anticipated from exposure to these solvents and pesticides in groundwater when either consumed or used for showering. Although the private wells off-site were not contaminated, FDOH cannot conclude that off-site groundwater is safe due to the lack of comprehensive off-site sampling.
The U.S. Department of Health and Human Services has classified tetrachloroethylene, trichloroethylene, dichloroethylene, cresol, chlorophenol, DDE and chlordane as either "possible" or "probable carcinogens". Results from animal studies suggest that these compounds may be capable of causing cancer, but only limited evidence in humans has been found (ATSDR, 1989, 1992b, 1994, 1996a; 1997a; 1997b; 1999b). Given the low estimated doses of these compounds in relation to this site and the weak carcinogenicity of these compounds, it is unlikely that the estimated exposures to these chemicals in drinking water would cause cancer.
22.214.171.124 Vinyl chloride- Vinyl chloride, like the other organic contaminants, was not detected in soil or sediment samples.
However, consumption or showering with on-site groundwater could deliver a dose that exceeds the oral and inhalation MRL (Tables 11 and 14, Appendix B). These doses could cause a mild, non-symptomatic effect on the liver. Mild liver responses have been observed in mice chronically treated with only slightly higher doses than those estimated for this site. FDOH, however, does not anticipate illness from vinyl chloride because groundwater samples taken in 1994 did not contain vinyl chloride and currently no functioning private well exists on the site.
Vinyl chloride can cause liver cancer by both oral and inhalation exposure routes and at doses only slightly higher than what could be encountered with this site (ATSDR, 1997c). However, FDOH does not anticipate an increase in illness or cancer from use of on-site groundwater due to the absence of vinyl chloride from the most recent groundwater samples and the absence of an on-site private well.
126.96.36.199 Aluminum - The concentration of aluminum in on- or off-site soil was not high enough to consider this metal a COC in soil (Table 4, Appendix B). Therefore, aluminum exposure from contaminated soil will not likely cause illness in area residents.
Using the maximum groundwater concentration, we estimated the maximum dose for a child and for an adult. These doses were calculated under conditions where residents are living on-site and consuming groundwater from an on-site well. The dose expected from off-site groundwater would be only slightly less (Tables 12 and 15, Appendix B), since the groundwater concentrations of aluminum were very similar between on- and off-site. The MRL for aluminum is based on a study where mice exhibited a decreased motor activity after treatment for six weeks with aluminum (Golub et al., 1989). Scientists have also found that certain populations may be susceptible to aluminum neurotoxicity (ATSDR, 1999c). Persons with reduced kidney function are at an increased risk of aluminum accumulation and therefore, are susceptible to the toxic effects of aluminum. The percent of aluminum absorbed is normally very low (<1%), but in persons that do not excrete the aluminum as efficiently (kidney disorders), the aluminum may accumulate. Although the calculated doses are above the MRL, we do not anticipate aluminum exposure to cause illness because the typical dose from chronic antacid use is 6 to 35 times the MRL and no health effects have been associated with chronic antacid use.
Available cancer studies of aluminum in animals do not indicate that aluminum is carcinogenic. Studies in humans show no correlation between aluminum and cancer mortality (ATSDR, 1999c). Therefore, consumption of aluminum in groundwater is unlikely to cause cancer.
188.8.131.52 Arsenic - The dose of arsenic that could be ingested in either on-site or off-site soil is less than the MRL for arsenic (Table 13, Appendix B). Therefore, we do not anticipate ingestion of arsenic in soil will cause illness.
Ingestion of arsenic in groundwater, either on-site or off-site, however, could result in a dose of arsenic that would exceed the MRL (Tables 12 and 15, Appendix B). Comparable doses for a period of up to 20 years in humans was associated with abdominal pain, anemia and mild tingling of hands and feet (Mazumder et al., 1988). Similar symptoms could be expected in relation to this site.
Arsenic is classified as a known human carcinogen by the EPA, ATSDR and IARC (International Agency for Research on Cancer). Arsenic exposure from consumption of groundwater could cause a moderate increase the risk of skin, bladder, lung, and liver cancers (ATSDR, 1999d). Based on the low concentration present in soil, ingestion of on-site soil could deliver a dose one-tenth of the dose associated with skin cancer in humans. FDOH concludes that ingestion of arsenic in soil could cause a low increase in the risk of bladder, kidney and skin cancer.
184.108.40.206 Barium - The concentration of barium in on- or off-site soil was not high enough to consider this metal a COC in soil (Table 4, Appendix B). Therefore, barium exposure from contaminated soil will not likely cause illness in area residents.
The estimated dose of barium that could be ingested from groundwater, either on-site or off-site exceeds the ATSDR MRL (Tables 11 and 14, Appendix B). In one animal study, barium doses, comparable to those estimated from this site, caused an increase in blood pressure (ATSDR, 1992c). Therefore, exposure to barium from this site does pose a mild health hazard. Individuals taking barbiturates or having a pre-existing heart condition may be at an increased risk.
The cancer classification of barium is currently "not classified". No evidence exists to suggest that barium causes cancer (ATSDR, 1992c).
220.127.116.11 Cadmium - The concentration of cadmium in soil was not high enough to consider this metal a COC in soil (Table 4, Appendix B). Therefore, cadmium exposure from contaminated soil will not likely cause illness in area residents.
Our estimates of doses of cadmium from drinking either on- or off-site groundwater are above the MRL, which is based on a human population chronically consuming cadmium. Based on the calculated doses, mild kidney toxicity is possible from consumption of groundwater either on-site or off-site. Children may be at an increased risk for kidney toxicity because younger animals tend to more efficiently absorb cadmium (Ogoshi et al., 1989). Persons with pre-existing kidney conditions may also be at an increased risk.
Cadmium is classified as a "probable human carcinogen" based on human and animal studies. The association between cadmium exposure and cancer applies more to inhalation exposure. The oral doses of cadmium that have been associated with cancer development in animal studies are over 300 times the doses that we estimated in this report. No cause-effect relationship has been established between oral exposure to cadmium and cancer. Therefore, we do not anticipate cadmium in the groundwater will cause cancer (ATSDR, 1999e).
18.104.22.168 Chromium - This estimated oral dose of chromium from ingestion of on-site surface soil exceeds the MRL (Table 13, Appendix B). Doses comparable to what was estimated on-site have previously been shown to cause abdominal cramping, diarrhea and dermatitis in humans (Kaaber and Veien, 1977; Zhang and Li, 1987). Therefore, ingestion of chromium from contaminated on-site surface soil could cause illness. The air concentration of chromium due to chromium in dust is below the inhalation MRL and, therefore, should not cause illness (ATSDR, 1998).
On-site and off-site sampling of groundwater detected chromium at high enough concentrations to produce a dose that would exceed the MRL (Tables 12 and 15, Appendix B). These doses could be associated with similar symptoms as those described above for ingestion of soil.
In humans, inhalation exposure to chromium has been associated with lung cancer in humans. However, the air concentration that caused lung cancer in humans is 500 times higher than the estimated air concentration at this site. Therefore, inhalation of chromium from contaminated soil is unlikely to cause cancer. No studies have demonstrated that ingestion of chromium causes cancer and therefore, ingestion of chromium in soil or groundwater is also not likely to cause cancer (ATSDR, 1998).
22.214.171.124 Lead - Currently no oral or inhalation MRL exists for lead. Therefore, all exposure scenarios are evaluated.
We estimated that the doses of lead resulting from incidental ingestion of on-site surface soil could likely cause several, mild responses (Table 13, Appendix B). These responses include disturbances in the blood cells, the vision system, the heart, the liver, the neurological system and reproductive system (ATSDR, 1999f).
The estimated doses of lead from consuming contaminated water (Tables 12 and 15, Appendix B) are likely to produce symptoms similar to those that would be expected from exposure through ingestion of contaminated soil. Of special importance in both of the exposure pathways described above, children absorb substantially more lead than adults and thus, are more sensitive to lead contamination.
Currently lead is classified as a "possible human carcinogen", based on limited human evidence. No studies have been published that demonstrate the cancer-causing effect of ingestion of lead. In animal studies, lead was shown to be carcinogenic at doses at least 200 times the estimated doses for this site. Therefore, it is unlikely that lead ingestion will cause cancer.
126.96.36.199 Mercury - The concentration of mercury in soil was not high enough to consider this metal a COC in soil (Table 4, Appendix B). Therefore, mercury exposure from contaminated soil will not likely cause illness in area residents.
The maximum dose of mercury that could be expected from consumption of off-site groundwater is equal to the MRL (Table 15, Appendix B) (ATSDR, 1999g). Mercury was not detected in on-site groundwater. Therefore, we do not anticipate any illness due to mercury in groundwater or soil.
Cancer: No evidence from human studies indicates an increased risk of cancer from mercury-contaminated water (ATSDR, 1999g).
188.8.131.52 Nickel - The concentration of nickel in on- or off-site soil was not high enough to consider this metal a COC in soil (Table 4, Appendix B). Therefore, nickel exposure from contaminated soil will not likely cause illness in area residents.
Only off-site groundwater only contained a concentration of nickel that if used as potable water could deliver a dose (Table 15, Appendix B) that exceeds the MRL. This dose of nickel could induce an allergic inflammation of the skin (ATSDR, 1997d). Other than this skin response, we do not anticipate these doses of nickel to cause any other illnesses.
No studies were located that associated nickel and cancer development in humans. Animal studies have not shown nickel to induce cancers in mice or rats (ATSDR, 1997d).
184.108.40.206 Selenium - The concentration of selenium in on- or off-site soil was not high enough to consider this metal a COC in soil (Table 4, Appendix B). Therefore, selenium exposure from contaminated soil will not likely cause illness in area residents.
We estimated that the maximum concentration of selenium in off-site groundwater could deliver a dose just slightly above the MRL (Table 13, Appendix B) (ATSDR, 1996b). We do not anticipate illness from these doses of selenium because, of the many human studies presented in the toxicological profile, no health effects were produced by doses comparable to those estimated for this site.
Currently, the carcinogenic category of selenium is "not classified". However, several studies have shown no association of selenium intake and the incidence of cancer. Therefore, it is unlikely that exposure to this low dose would cause cancer.
220.127.116.11 Thallium - The concentration of thallium in on- or off-site soil was not high enough to consider this metal a COC in soil (Table 4, Appendix B). Therefore, thallium exposure from contaminated soil will not likely cause illness in area residents.
We estimated that consumption of both on- and off-site groundwater could deliver doses that would exceed the oral MRL (Tables 12 and 15, Appendix B). However, results from animal studies have shown that doses as much as 100 times those estimated for this site caused no deleterious effect (ATSDR, 1992d). Therefore, with the exception of people with preexisting neurological, kidney or liver diseases, is it unlikely that these low concentrations of thallium would cause illness.
Currently, the cancer class of thallium is "not classified". No studies in humans or animals have examined an association between thallium exposure and cancer (ATSDR, 1992d).
18.104.22.168 Vanadium - The concentration of vanadium in soil was not high enough to consider this metal a COC in soil (Table 4, Appendix B). Therefore, vanadium exposure from contaminated soil will not likely cause illness in area residents.
We estimate that consumption of both on- and off-site groundwater would deliver a dose that slightly exceeds the MRL (Tables 12 and 15, Appendix B). However, studies in both humans and animals showed no toxicity of vanadium doses as much as ten times the doses estimated with this site (ATSDR, 1992e).
Currently, the cancer class of vanadium is "not classified". No studies in humans or animals have examined an association between vanadium exposure and cancer.
4.5.2 Children and Other Unusually Susceptible Populations - The unique vulnerabilities of infants and children demand special emphasis in communities faced with the contamination of their environment. Children are at a greater risk than adults from certain kinds of exposure to hazardous substances emitted from waste sites. They are more likely to be exposed because they play outdoors and because they often bring food into contaminated areas. They are shorter than adults, which means they breathe dust, soil, and heavy vapors close to the ground. Children are also smaller, resulting in higher doses of chemical exposure per body weight. In addition, the developing body systems of children can sustain permanent damage if toxic exposures occur during critical growth stages. Most importantly, children depend completely on adults for risk identification and management decisions, housing decisions, and access to medical care.
As of February 2000, there are no records of community health concerns.
Because of the limited data both on and off the site, FDOH classifies the Callaway and Son Drum Service hazardous waste site as an "indeterminant public health hazard". The contamination of the soil and groundwater, both on-site and off-site, have not been adequately characterized. Without sufficient data, we are unable to make a definitive determination. In areas of contamination, no receptor population was identified. In areas with a receptor population, no contamination has been identified. FDOH makes the following conclusions based on the limited data collected to date:
- Health hazards exist on-site in the form of a damaged building and chemical contamination of the surface soil. Exposure to on-site soil contaminants could cause illness in on-site populations (i.e., trespassers or future residents).
- Incidental ingestion of on-site soil by trespassers or future residents could deliver a dose of chromium and lead high enough to cause illness. The estimated amount of chromium from incidental ingestion could cause abdominal cramping, diarrhea and skin irritation/inflammation. The estimated dose of ingested lead from soil could cause mild changes in blood, vision, blood pressure, the liver, the neurological system and reproductive system.
- Incidental ingestion arsenic in contaminated on-site soil could cause a low increased risk of cancer.
- None of the soil samples or surface water samples taken from off of the site contained any of the contaminants detected on-site. However, the extent of off-site soil contamination has not been adequately characterized. Therefore, FDOH cannot conclude that off-site soil is safe. Specifically, no soil samples were taken from south of the site, where surface water flows and access is unrestricted.
- Exposure to on-site groundwater contaminants could introduce a significant health hazard to on-site populations (i.e., future residents), but only if a potable well is drilled into the surficial aquifer on-site.
- Exposure to metals in on-site, surficial groundwater is likely to cause illness. Abdominal pain, diarrhea, increased blood pressure, kidney toxicity, anemia, tingling in the extremities and skin irritation are probable effects of consumption of on-site groundwater containing arsenic, barium, cadmium, chromium, nickel and lead.
- Consumption of arsenic and cadmium in on-site groundwater is likely to increase the risk of cancer.
- Shallow groundwater samples taken north of the site contained similar metals as on-site groundwater and are likely to produce the same symptoms if ingested. In contrast, no contaminants were detected in the potable, Floridan aquifer wells south-southeast of the site. This suggests that either the contamination plume has not reached these wells, or the contaminants have not reached the Floridan aquifer.
- The contamination of both on- and off-site groundwater has not been adequately characterized. Specifically, the horizontal and vertical extent of contamination and the direction of contaminant movement have not been defined. Therefore, whether contaminants are likely to even reach a receptor population is not known.
Because the potential exposure pathways that could increase illness and cancer are from exposure to contaminated soil and groundwater, the following recommendations focus on reducing these exposures.
- Restrict access to the site.
- Determine the lateral and vertical extent of soil contamination by collecting soil samples from the southern portion of the property, both on-site and off-site, and sediment samples from the drainage ditch which runs south through a residential area to Lake Haines.
- To protect on-site residents, restrict the drilling of potable wells on the Callaway and Son property.
- To ensure that private, potable wells are not contaminated, FDOH recommends that wells within a 0.5 mile radius of the site (Figure 2, Appendix A) be tested for contaminants of concern.
- Determine the lateral and vertical extent of off-site groundwater contamination by further sampling of the surficial and Floridan aquifers. In addition, confirm the direction of surficial and Floridan aquifer groundwater flow in this region.
This section describes what ATSDR and/or FDOH plan to do at this site. The purpose of a Public Health Action Plan is to reduce any existing health hazards and to prevent any from occurring in the future. ATSDR and/or FDOH will do the following:
- FDOH, Bureau of Environmental Toxicology will inform and educate nearby residents in the surrounding residential areas about the potential health threat at this site by:
- Circulating a fact sheet on the site and the contaminants detected.
- Offering to meet with area residents to discuss the site and the potential health hazards from the site.
- FDOH, Bureau of Environmental Toxicology will recommend that the Polk County Health Department sample private and public supply wells within a half mile south of the site to identify any potential receptor populations. The Polk County Health Department has agreed to provide assistance in the action.
- FDOH, Bureau of Environmental Toxicology will continue to work with environmental agencies to ensure that any cleanup activities protect public health and to follow up on the implementation of any recommendations presented in this report.
The conclusions and recommendations in this report are based on the information reviewed. When additional information becomes available FDOH, Bureau of Environmental Toxicology, will evaluate it to determine what additional recommendations, if any, to make.
Florida Department of Health, Author
Davis H. Daiker, Ph.D.
Bureau of Environmental Toxicology
Division of Environmental Health
ATSDR Technical Project Team
Division of Health Assessment and Consultation
Division of Health Studies
Division of Health Education and Promotion
ATSDR Regional Representative:
Office of the Assistant Administrator
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