PRELIMINARY PUBLIC HEALTH ASSESSMENT
AMERICAN CREOSOTE WORKS, INCORPORATED
WINNFIELD, WINN PARISH, LOUISIANA
The Tables in this section list the contaminants of concern. These contaminants are evaluated inthe subsequent sections of the health assessment and a determination is made as to whetherexposure to them has public health significance. The Section of Environmental Epidemiologyselects and discusses these contaminants based upon the following factors:
- Concentrations of contaminants on and off the site.
- Field data quality, laboratory data quality, and sample design.
- Comparison of on-site and off-site concentrations with health assessment comparison values for (1) noncarcinogenic endpoints and (2) carcinogenic endpoints.
- Community health concerns.
In the data Tables that follow under the On-site Contamination subsection and the Off-siteContamination subsection, the listed contaminant does not mean that it will cause adverse healtheffects from exposure. Instead, the list indicates which contaminants will be evaluated further inthe public health assessment. When selected as a contaminant of concern in one medium, thatcontaminant will be reported in all media.
The data tables include the following acronyms:
CREG = Cancer Risk Evaluation Guide.
EMEG = Environmental Media Evaluation Guide.
RMEG = Reference Dose Media Evaluation Guide, calculated from EPA's Reference Dose.
Comparison values for the health assessment are contaminant concentrations in specific media thatare used to select contaminants for further evaluation. These values include Environmental MediaEvaluation Guides (EMEGs), Cancer Risk Evaluation Guides (CREGs), and other relevantguidelines. CREGs are estimated contaminant concentrations based on one excess cancer in amillion persons exposed over a lifetime. CREGs are calculated from EPA's cancer slope factors. EPA's Reference Dose (RFD) is an estimate of the daily exposure to a contaminant that is unlikelyto cause adverse health effects.
EPA collected the data presented in this subsection during its Site Assessment in 1992 (1-5). Chemicals selected as the contaminants of concern are presented in the following tables.
Surface Soil (0-3")
Twenty one surface soil samples were collected during February and March of 1992 for theRemedial Investigation and Feasibility Study (RI/FS) at the American Creosote site. The sampling locations are shown in Figure 1.2. Portions of the site for which surface soil data exist include:
- former process area
- former impoundment area
- drainage area north and northeast of the process area
- portion of the site north of Creosote Branch
- southern portion of the sit
- office area west of Creosote Branch
The contaminated surface soil samples are in the former process area, impoundment areas, thedrainage area, and north of Creosote Branch. Detected chemicals are benzo(a)pyrene (B(a)P),polycyclic aromatic hydrocarbons (PAHs), pentachlorophenol (PCP), and 2,3,7,8, TCDD. Table1 reports the contaminants and their concentrations.
|Contaminant||PA||IA||DA||CB||Comparison values |
|2,3,7,8, TCDD||5.32||ND||ND||ND||0.002 EMEG|
- PA - Process area
IA - Impoundment area
DA - Drainage area
CB - Creosote branch
Subsurface Soil (5-20")
During the installation of 11 monitor wells, EPA collected subsurface soil samples from 18boreholes. Samples were taken at about 0-20 feet. Figure 1.2 and 1.3 illustrate subsurface soilsampling locations. Tables 2.1 and 2.2 report the contaminants and concentration ranges. Theportions of the site for which subsurface soil data exist include:
- former process area
- former impoundment and drainage area northeast of the process area
- tarmat area
- waste cell constructed during the removal action
- southern portion of the site
- portion of the site north of Creosote Branch
|Contaminant||Process area||Impoundment area||Tarmat area||Ref.||Comparison value (ppb)|
- ppb - parts per billion
|Contaminant||Waste cell||Southern portion||North of Creosote Branch||Ref||Comparison value|
|2,3,7,8 - TCDD||3.23||0.002||ND||1||0.002 EMEG|
- ppb - parts per billion
- Creosote branch upstream
- a ditch upstream of the site
- pond on the site
- Creosote branch downstream of the site drainage ditches
- Creosote branch in the northwest portion of the site, upstream of the confluence with anunnamed tributary and with the majority of the site drainage ditches.
The contaminant detected in these samples was PCP. Table 3 reports the contaminant and itsmaximum concentration.
|Contaminant||Sample ID||Level (ppb)||Ref.||ComparisonValues (ppb)|
- ppb - parts per billion
The pond has a surface area of approximately 0.5 acres, and a depth of eight feet. It wasconstructed as a reservoir for storage of fire protection water.
EPA collected 6 sediment samples at different locations illustrated in Figure 1.2 and 1.3. Contaminants detected in some of these samples include total PAHs, and B(a)P. Table 4 reports the contaminants and their maximum concentrations. Sediment sample from the pond on the site did not indicate any contamination.
|Contaminant||Sample ID||Level (ppb)||Ref.||Comparisonvalues (ppb)|
|Total PAHs||SD-2 |
|2,3,7,8 TCDD||SD-3||0.01||1||0.002 EMEG|
- ppb - parts per billion
During our site visit we could detect a heavy smell of creosote all over the site even at the gateentrance. Air sampling data was not available, however, it was reported that previousinvestigations found no emissions at the site's perimeter (8).
Groundwater (Monitor Wells)
The shallow aquifer (5-30 feet deep) was found to contain contaminants similar to those found insoil and subsurface soil. Wells screened at 5 to 20 feet were reported to contain one foot offloating creosote and several inches of floating oils.
EPA did on-site sampling of four deep and seven shallow monitoring wells both up and downgradient of the contaminated portions of the site. The shallow monitoring well boreholes werescreened in fine to medium sand and gravel in the top ten feet of the aquifer and ranged from 20-25 feet in total depth. Deep monitoring wells were screened in a fine sand and silty zoneapproximately 65 feet below grade. Figure 1.5 shows the locations of these well samples, and Table 5 reports the contaminants and concentration range. The shallow aquifer zone dischargesinto Creosote Branch along the northern and western site boundaries. Flow direction within mostof the site is to the north towards Creosote Branch. Shallow and deep potentiometric surfacesreveal the presence of an upward vertical gradient across the site. Shallow monitoring well MW-1A and deep monitoring well MW-1 were installed on the southern portion of the site to provide data on groundwater quality upgradient of contaminant sources present on the site. Areas of greatest groundwater contamination are the former process area and the impoundment area. Well MW-4, north of the former process area, was screened from 11 to 21 feet and well MW-6 was screened from 5 to 20 feet. Shallow monitoring wells MW-3A and MW-5 were screened from 5 to 20 and 17 to 27 feet, they are within the area of contaminated soils surrounding the process and impoundment areas.
|Contaminant||Wells ID||Levels (ppb)||Ref.||Comparison values (ppb)|
- ppb - parts per billion
Deep monitoring wells installed to the east (MW-3), west (MW-2) and north (MW-7) of theformer process area show no contamination. Analysis of groundwater data from the shallowmonitoring wells reveals contamination with PAHs, B(a)P, benzene and phenols. Samplescollected from deep monitoring wells (depth 55-65 feet) contained no detectable contamination.
EPA did an ecological exposure assessment which showed that the site is currently posing a threatto the aquatic environment because of potential effects of contaminated surface water, soil, andsediment from the American Creosote site (6).
Biota sampling was attempted but no fish were caught (8), therefore, no data are available.
Off-site sampling of soil, surface water, air, or biota was not conducted.
It has been reported that previous perimeter air sampling at the site did not show contamination(8), therefore no off-site air monitoring was conducted.
Three sediment samples were collected downstream of the site. SD-7 is nearly a mile downstream of the site. Sediments samples SD-9 and SD-10 were collected from Creosote Branchapproximately 6,300 feet and 10,000 feet downstream of the site. Table 6 reports thecontaminants and their concentrations.
|Contaminant||Sample ID||Level (ppb)||Ref.||Comparison value (ppb)|
|Total PAH||SD-7 |
- ppb - part per billion.
Groundwater (Public Supplies)
EPA collected a ground water sample from a nearby municipal drinking water supply wellbelonging to the Red Hill Water Cooperation (Figure 1.6). This well is off the site approximatelyone mile from the site on Highway 167, approximately 200 yards north of Creosote Branch. It isscreened from approximately 550 to 600 feet in the Sparta sand. The only compounds detected inthe sample from this well were PAHs (acenaphthene, fluorene) but the levels did not exceedcomparison values. A resample of this well indicated no PAHs or phenol.
Biota sampling was attempted but no fish were caught (8), therefore, no data are available.
Bioassays were conducted on sediment and surface water along 2 miles of Creosote Branch,however, no surface water data were located.
The analysis and conclusion presented in this public health assessment are based on data containedin the RI/FS study submitted to EPA. The availability of the conclusions drawn are determined bythe accuracy and reliability of the referenced information. The contractor at this site, upon reviewof the data analysis, states that all the data are acceptable and reliable.
The site is fenced, however a rusty pressure vessel labeled "hazardous waste inside" and severaldrums on the site represent physical hazards, especially to trespassing children. The vessel didcontain contaminated material that would have posed a hazard if touched or inhaled.
To determine whether nearby residents are exposed to contaminants migrating from the site, theSection of Environmental Epidemiology evaluated the environmental and human components thatlead to human exposure. This pathways analysis consists of five elements: A source ofcontamination, transport through an environmental medium, a point of exposure, a route ofhuman exposure, and an exposed population.
ATSDR categorizes an exposure pathway as a completed or potential exposure pathway if theexposure pathway cannot be eliminated. Completed pathways require that the five elements existand indicate that exposure to a contaminant has occurred in the past, is currently occurring, orwill occur in the future. Potential pathways require that at least one of the five elements ismissing but could exist. An exposure pathway can be eliminated if at least one of the fiveelements is missing and will never be present. Only those pathways that are important andrelevant to the site will be discussed.
Past, and possibly current and future, exposure pathways are likely from contact withcontaminated on-site surface soil. Incidental soil ingestion and dermal contact are consideredroutes of exposure, particularly for workers on the site who are involved in remediation, and forresidents who trespass the site, particularly children. It is documented that children used the siteas a ballfield and playground. In addition, prior to 1988 the site was not fenced and localresidents, including school children, frequently crossed it on a trail that extended from the siteaccess road to the residential street that forms the southeast site boundary.
Past, and possible current and future, exposure to contaminated sediments are likely from the useof Creosote Branch. Past exposure through dermal contact, and possibly ingestion, exists becausechildren that were interviewed on the site prior to fencing claimed to have regularly swam inCreosote Branch. Present and future exposure exists for those who trespass the site or useCreosote Branch for recreational activities.
Past, and possibly present and future, exposures are likely to occur from contact with surfacewater contamination in Creosote Branch. Surface water run-off from American Creosote drainsinto Creosote Branch, which bounds the site to the west and crosses the northern portion of thesite. The drainage ditches that traverse the site receive surface water runoff from the process areaand subterranean seepage of creosote wastes that appear to have infiltrated into the soil. Pools ofthese liquids collect in the bottoms of the ditches and are washed into Creosote Branch by rainfallrunoff. Residents, particularly children, who use Creosote Branch for recreational activities arelikely to get exposed through dermal contact and incidental ingestion.
|Pathway Name||Exposure Pathway Elements||Time|
|Source||Environmental Media||Point of Exposure||Route of Exposure||Exposed Population|
|Surface soil||Site||Surface soil||On-site||Ingestion and Dermal Contact||Workers and Residents||Past |
|Ingestion and Dermal Contact||Workers and Residents||Past |
|Surface water||Site||Surface water||On-site||Ingestion and Dermal contact||Workers and Residents||Past |
|Air||Site||Air||On-site||Inhalation||Workers and Residents||Past |
|Pathway Name||Exposure Pathway Elements||TIME|
|Source||Environmental Media||Point of Exposure||Route of exposure||Exposed population|
|Soil||Site||Soil||Residential yards |
|Ingestion and |
|Sediment||Creosote Branch||Sediment||Port du luce||Ingestion and |
|Surface water||Creosote Branch||Surface water||Port du luce |
|Ingestion and |
|Fugitive dust||Site||Air||Off-Site||Inhalation||Residents |
|Public water supply||Site||Groundwater||Residences||Ingestion |
|Private wells||Site||Groundwater||Residences||Ingestion |
|Biota||Creosote Branch||Biota||Creosote Branch |
Port du Luce
This exposure pathway is considered complete based on the experience of the Section ofEnvironmental Epidemiology and DEQ who reported a heavy smell of creosote on the site duringour site visit. Past, present, and probably future exposure to contaminated ambient air is likely forresidents trespassing the site and remediation workers. Prior to 1988 the site was not fenced andlocal residents, including school children, frequently crossed it on a trail that extended from thesite access road to the residential street that forms the southeast site boundary.
According to reports from individuals who previously worked at the American Creosote facilityand their families, workers came in contact with the various chemicals used in the operations. They reported being covered in dust. The contaminants and their concentrations were notmeasured, therefore, no estimate of actual exposures can be made.
Hazardous waste Workers
Site investigation and remediation workers who fail to follow the Occupational Safety and HealthAdministration (OSHA) personal protection regulations are at risk of exposure when in contactwith the contaminated media described previously.
Residential neighborhoods are present in all directions from the site. The closest are theseventeen houses bordering the site. There is a housing development that lies to the south of theAmerican Creosote site along Mcleod and Watts Streets (Figure 1.3). Potential exposure to contaminants could occur because of several environmental transport mechanisms. Thesemechanisms include transport of site contaminants by wind, surface water runoff, and flooding. Receptor populations are the residents living in the seventeen houses bordering the site.
Contaminated sediments were detected on the site and off the site at the Creosote Branch whichjoins with Port Du Luce Creek. It was reported that the sediment samples taken along 2 miles ofCreosote Branch were not above EPA's allowable risk range for human health (8). Sediment contamination further downstream from there should have even lower concentrations, however,there are no data from the Port du Luce Creek or Dugdemona River to substantiate that assumption.
Contaminated surface water was detected in Creosote Branch which empties into Port Du LuceCreek. Like off-site sediments, it was reported that the surface water samples taken along 2 milesof Creosote Branch appear to be uncontaminated (8). Surface water contamination further downstream from there should have even lower concentrations, however, there are no data fromthe Port du Luce Creek or Dugdemona River to substantiate that assumption. Residents do usePort Du Luce Creek for recreational activities.
Biota sampling was attempted but no fish were caught (8), therefore, no data are available. Future exposures are possible if biota from Creosote Branch, Port du Luce, or the DugdemonaRiver are contaminated and eaten. Contaminants leaching into the site's drainage ditches willempty into the Creosote Branch. There are various species of fish, crawfish, and other wildlifeliving in various locations along Creosote Branch adjacent to and upstream of the site. Residentsand children use these points of exposure for recreational activities. There is no commercialagriculture or livestock production/grazing on areas of visible contamination, however huntinggame does occur in this area.
Dust clouds have been reported on the site. Since the site is open, flat, and only sparselyvegetated, there exists the threat from contaminated particulates during dry, windy period toresidents of the seventeen houses bordering the site.
Groundwater (Public Water Supply)
According to information on file at Louisiana Department of Transportation and Development, 12water wells are within a one mile radius of the site. The depth ranges from 480-600 feet. Ofthese 12 wells, three are public water supply, three are abandoned public water supply, five aretest wells, and one is an observation well. Groundwater in the site area is found in two separateaquifers. Wells screened in the shallow aquifer (5-30 feet deep) on the site were found to containcontaminants similar to those found in soil and subsurface soil. Thus, downward migration of thecontaminants is occurring but it may not reach the deep aquifer because beneath the shallowaquifer is 20 feet of relatively dry interbedded silty sands and silty clays that appear to becontiguous across the area. These layers, in addition to the upward gradient or artisan effects ofthe lower groundwater may act to decrease the downward movement of contaminants to the nextlower aquifer at 55 to 65 feet deep. Groundwater from these aquifers is not used in the vicinity ofthe site as a drinking water source.
No residential wells showed up on well surveys (8), but it is possible there are unreported private wells. Potential exposure to contaminated groundwater would be possible if contamination doesmigrate off the site and residential wells were installed within the contaminated area or if theshallow aquifer is used as a source of potable water. The potential receptor population would befuture users of new wells.
This section will discuss the health effects in persons exposed to specific contaminants, evaluatestate and local health databases, and address specific community health concerns. To evaluatehealth effects, ATSDR has developed minimal risk levels (MRLs) for contaminants commonlyfound at hazardous waste sites. The MRL is an estimate of daily human exposure to acontaminant below which non-cancer, adverse health effects are unlikely to occur. The MRLs aredeveloped for each route of exposure, such as ingestion and inhalation, and for length ofexposure, such as acute (14 days or less), intermediate (15 to 364 days), and chronic (365 days orgreater). The ATSDR presents these MRLs in Toxicological Profiles. These chemical specificprofiles provide information on health effects, environmental transport, human exposure, andregulatory status. When MRLs are not available, reference doses (RfD) provided by the EPA areevaluated. For carcinogenic substances, EPA has established the Cancer Slope Factor (CSF) as ahealth guideline. The CSF is used to determine the number of excess cancers expected fromexposure to a contaminant.
The health effects which result from the interaction of an individual with a hazardous substance inthe environment depend on several factors. One is the route of exposure: that is, whether thechemical is breathed, consumed incidentally in contaminated soil or sediment or eaten incontaminated food or water, or contacts the skin. Another factor is the dose to which a person isexposed and the amount of that exposure dose that is actually absorbed. Mechanisms by whichchemicals are altered in the environment, or inside the body once absorbed are also important. Agreat deal of variation exists among individuals.
The following toxicological evaluation will evaluate the potential for adverse health effects fromthe previously discussed Completed Exposure Pathways section. Potential exposure pathwayslack sufficient information for further evaluation. According to community reports, workerexposure during previous facility operations is a completed pathway for past exposures, however,because of the absence of data, exposure doses and potential health effects can not be evaluated. From community reports and our observations during site visits, exposure to contaminated air onthe site has occurred. Again, the absence of data prohibits an estimation of exposure doses andpotential health effects.
SEE has reviewed the toxicological profiles for chemical substances of concern at the AmericanCreosote site. These documents interpret health effects information on the substances and specifythe level at which people might be harmed.
Polycyclic Aromatic Hydrocarbons
Polycyclic aromatic hydrocarbons (PAHs) are a class of structurally related compounds. As agroup, these compounds have similar characteristics.
Exposure to PAHs through incidental ingestion and dermal contact with contaminated surfacesoils and sediments may have occurred and may still be occurring on the site among workers andtrespassers, particularly children. Off-site sediments are also a source of exposure to PAHs forresidents and workers. Persons could potentially be exposed to PAHs through consumption ofcontaminated fish or game animals in the vicinity of the site, but biota samples are not availablefor evaluation. Using the highest total PAH concentration detected in on-site surface soil (208.9ppm), the ingestion exposure for adults and older children does not exceed ATSDR's acute MRLof 0.1 mg/kg/day for benzo(a)pyrene and other PAHs. Using the highest total PAHconcentration detected in off-site sediment (6.81 ppm), the ingestion exposure for youngerchildren (1 year through 6 years of age) who have pica habits does not exceed the acute oralMRL. That MRL is based on an animal study in which developmental effects were seen in theoffspring of mice following in utero exposure to benzo(a)pyrene. In determining the exposuredoses, we assumed that a pica child ingests 5000 mg of soil per day; that a non-pica child ingests500 mg of soil per day, and that adults ingest 100 mg of soil per day. Neither ATSDR nor EPAhave developed chronic health guidelines, i.e., MRLs and RfDs, for the PAHs. Generally it can beassumed that chronic health guidelines are lower doses than are acute health guidelines.
Studies in animals have shown that PAHs can cause harmful effects on the liver and blood. Thelevels of PAHs at which those effects were first seen are orders of magnitude higher than theestimated dose for younger children. Therefore, the maximum level of PAHs found in the on-sitesoil are unlikely to cause those effects in the most susceptible population, younger children. Contaminated sediment data was lower than the on-site soil data, therefore health effects fromexposure to the sediment are less likely than the on-site soils.
Using the same highest PAH concentration in on-site soil and the cancer potency factor for B(a)P,we estimate there to be no apparent increased risk of cancer from incidental ingestion ofcontaminated soil. For the off-site sediment exposure, we estimate an insignificant increasedcancer risk. This is based on the assumption that a person is exposed 5 days a week, 50 weeks ayear for 30 years and incidentally ingests 50 mg of soil per day.
ATSDR does not have MRLs for skin exposure to PAHs. For that reason, it is difficult todetermine the health effects from skin exposure. Adverse skin effects have been noted in animalswith acute and subchronic dermal exposures to PAHs. Those effects include destruction ofsebaceous glands (glands in the skin which secrete fatty substances), skin ulcerations, hyperplasia(abnormal increase in number of skin cells), and overgrowth of the outer layer of the skin. Dermal exposure to certain PAHs, such as anthracene and phenanthrene, followed by exposure tosunlight may result in phototoxic effects such as erythema (redness of the skin), urticaria (elevatedpatches of skin), and burning and itching. Persons with pre-existing skin conditions may bemore sensitive to the adverse dermal effects of PAHs (8).
Several of the PAHs, including benzo(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene,benzo(k)fluoranthene, chrysene, dibenzo(a,h)anthracene, and ideno(1,2,3-cd)pyrene have causedtumors in laboratory animals through ingestion, skin contact, and inhalation. Epidemiologicstudies of workers occupationally exposed to PAHs have provided limited evidence that PAHexposure may contribute to increased incidence of skin, lung, and genitourinary cancers. Themost likely exposure routes in the occupational settings were through inhalation and skin contactwith those compounds. Although inhalation of contaminated dusts is possible on the site and inthe residential areas, potential health effects cannot be evaluated without air sampling data.
Exposure to pentachlorophenol has probably occurred to trespassers and workers via ingestionand dermal exposure to PCP contaminated on-site surface water and soil. The highest levels ofpentachlorophenol in surface soil and surface water were 2.3 ppm and 0.068 ppm, respectively,both on-site samples. ATSDR has set an acute oral MRL of 0.005 mg/kg/day and an intermediateoral MRL of 0.001 mg/kg/day for pentachlorophenol. Based on the soil ingestion rates for adultsand children discussed under PAHs and the highest levels of pentachlorophenol found, theingestion exposures to on-site soil for adults and children do not exceed ATSDR's acute andintermediate MRLs. The estimated exposed doses for ingested on-site surface water for childrendoes exceed the intermediate MRL and slightly exceeds the acute MRL. Adult exposure doses donot exceed either MRL. EPA's RfD of 0.03 mg/kg/day is not exceeded by either the child or adultestimated exposure doses.
Animal studies have indicated that long-term exposure (greater than 14 days) to low levels ofpentachlorophenol can have adverse effects on the liver, kidney, nervous system, and immunesystem. Studies have also indicated that long-term exposure to low levels of pentachlorophenolencountered in the workplace can cause damage to the liver, kidney, blood, and nervous system. The levels of pentachlorophenol found in the on-site surface soils and surface water are unlikelyto result in those adverse health effects.
ATSDR could not locate any adequate studies that described significant levels of skin exposure topentachlorophenol. Occupational exposures to pentachlorophenol have been associated withsevere skin eruptions. Nonoccupational exposures to wood treated with pentachlorophenol havebeen associated with pemphigus vulgaris (a serious skin disease characterized by blisters and lossof skin) and chronic urticaria (a disorder of the skin characterized by itchy pink or white wheals). Skin effects discussed above may have resulted from impurities present in pentachlorophenol fromthe manufacture of this chemical (10). The toxic dermal effects of pentachlorophenol appear tobe most serious following high-dose, acute exposure.
Sufficient evidence exists from animal studies to suggest that pentachlorophenol might causecancer in humans. No convincing evidence has been obtained from human epidemiologicalstudies that indicate that pentachlorophenol causes cancer in humans. Case reports suggest apossible association between cancer (Hodgkin's disease, soft tissue sarcoma, and acute leukemia)and occupational exposure to technical pentachlorophenol that may have had other contaminants.
PCP is classified as a probable human carcinogen (Group B2) by EPA. Using the same highestPCP concentration in on-site soil and surface water , we estimate there to be no increased risk ofcancer from incidental ingestion of contaminated soil and a low to moderate increased cancer riskfrom the ingestion of the on-site surface water. The soil scenario is based on the assumption thata person is exposed 5 days a week, 50 weeks a year for 30 years and incidentally ingests 50 mg ofsoil per day. The surface water scenario is based on the assumption that a person ingests 1 liter ofwater 5 days a week for 30 years.
According to the documents reviewed, the most toxic chlorinated dioxin,2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD), was detected at the maximum concentrationof 5.32 ppb in on-site surface soil. It was also detected in lesser concentrations in subsurfacesoils. A maximum concentration of 0.01 ppb was detected in on-site sediment. Trespassers andworkers probably were exposed to the contaminated surface soil and sediment through incidentalingestion and dermal contact.
ATSDR has set an acute MRL of 0.0000001 mg/kg/day and an intermediate and chronic MRL of0.000000001 mg/kg/day for 2,3,7,8-TCDD. The estimated ingestion exposures for pica and non-pica children exceed ATSDR's chronic oral MRL and approximately equal the acute MRL for2,3,7,8-TCDD. Estimated ingestion exposures for adults exceed the chronic oral MRL but notthe acute MRL. The maximum on-site surface soil concentration does exceed ATSDR's level ofconcern of 1 ppb for residential soils, however, the sample was taken from the Process Area ofthe facility and does not reflect similar exposure conditions as residential soils. As stated in thePathways Analysis, off-site soil were not sampled.
Animal studies have indicated that 2,3,7,8-TCDD may cause liver damage; severe loss of bodyweight; damage to the immune system, and adverse reproductive effects including spontaneousabortions and malformations in animal offspring. Adverse effects of that chemical on the immunesystem, reproductive system and developing fetuses have not been found in humans, but someevidence has suggested that 2,3,7,8-TCDD might cause liver damage, weight loss, and digestivedisorders in humans. Chloracne is the only confirmed effect in humans produced by certaincompounds contaminated with 2,3,7,8-TCDD. Chloracne is a skin disease characterized byblackheads, cysts, pustules, and inflammatory (pain, redness, and swelling) skin changes ofvarying degrees of severity. A minimum toxic dose of 0.0001 mg/kg has been suggested toproduce adverse noncancer health effects in humans (13). Although the ingestion exposures forchildren equal the acute MRL for 2,3,7,8-TCDD and the ingestion exposures for children andadults exceed the chronic MRL for this chemical, all estimated exposures are well below the0.0001 mg/kg level. Therefore, it is unlikely that residents and workers would develop skin, liver,or digestive disorders from past or present exposures to the maximum levels of 2,3,7,8-TCDDfound on the site. Results from animal studies clearly indicate that 2,3,7,8-TCDD causes cancerin laboratory animals. Several epidemiological studies of human populations exposed toherbicides contaminated with 2,3,7,8-TCDD have shown an association with cancer that includedan increased incidence of soft tissue sarcomas, lymphomas, and stomach cancer. The evidencefrom human epidemiology studies is not conclusive because of inadequate exposure informationand concomitant exposures to other chemicals. Other epidemiological studies have found noassociation between exposure to substances containing 2,3,7,8-TCDD and cancer. 2,3,7,8-TCDD is classified as a probable human carcinogen (Group B2) by EPA, however, the cancer slope factor has been withdrawn and is currently undergoing review.
Communities near the site are very concerned with the health effects including cancer of thecontaminants found in the site.
Adequate cancer incidence data are not available at this time for Winn Parish. However, cancermortality data for Winn Parish is available from the Louisiana Office of Vital Statistics.
The Louisiana Office of Vital Statistics contains information about number of deaths of cancer bysite, address, age, race and sex for the state of Louisiana. A ratio of average age adjusted deathrates between 1989-1991 and 1979-1981 in Winn parish was calculated. No statisticallysignificant difference in cancer death rates has been found between 1989-1991 and 1979-1981(Table 9). Age adjusted death rates of cancer per 100,000 people (1989-1991) of Winn Parishand the entire state of Louisiana are shown in Table 10.
* Statistically significant
**Indicates 79-81 rate is zero and 89-91 rate is greater than zero
- Indicates 79-81 and 89-91 rates are each zero
|Lymphatic and Hematopoietic Tissue||13.04||11.91|
|All other sites||33.57||23.23|
The following is a list of questions posed by residents of Winnfield, Louisiana during the publicmeeting for American Creosote Superfund Site on January 13, 1993.
|1.||What are the possible health effects of drinking water contaminated with compounds from the site?|
|The municipal drinking water supply is safe for drinking purposes. Therefore, no adverse health effects are likely to occur.|
|2.||Is the municipal drinking water supply contaminated?|
|The municipal drinking water supply is not contaminated at the present time.|
|3.||What evidence supports this contention?|
|The groundwater contamination found in the shallow aquifer is at a depth of 5-30 feet. An underlying second aquifer (55-65 feet deep) has not shown any detectable contamination. Themunicipal water supply wells are much deeper at depths of 480-600 feet. Downward migration ofthe contaminants from the shallow aquifer is occurring but it may not reach the 55-65 foot aquiferbecause beneath the shallow aquifer is 20 feet of relatively dry interbedded silty sands and siltyclays that appear to be contiguous across the area. These layers, in addition to the upwardgradient or artisan effects of the lower groundwater may act to decrease the downward movementof contaminants to the next lower aquifer at 55 to 65 feet deep. A potential exposure tocontaminated groundwater would be possible if private wells were installed within groundwaterwhere the contaminants were present or if the shallow aquifer becomes a source of potable water.|
|4.||Should the citizens of Winnfield look for alternate drinking water supplies?|
|Citizens who use the municipal water supply do not need an alternate water supply because the aquifer from which the public water is taken has not been impacted by site contaminants. Although no residential wells were reported on well surveys (8), it is possible there are unreportedprivate wells. If any citizen has a private well screened in the contaminated shallow aquifer, theyshould request to have their water tested and, based on the results, may look for alternate watersupplies. Private wells should not be installed in the shallow aquifer.|
|5.||What carcinogens are present on the site and what cancers can they cause?|
|Selected PAH's were sampled for, in addition to group sampling. Data indicate that some PAH's can cause skin and lung cancer, as well as, gastrointestinal cancers. Benzene can cause leukemiabut was not found in completed exposure pathways. Pentachlorophenol and dioxin are bothprobable human carcinogens. Please refer to the Toxicological Evaluation section for additionalinformation.|
|6.||Are all carcinogens tested for in the municipal water supply?|
|All compounds identified on the site have been tested for in the municipal drinking water supply including carcinogens. None have been found.|
|7.||Does the health outcome data indicate a high incidence of cancer in the area?|
|Adequate incidence data are not available at this time for the area. Please refer to the Health Outcome Data Evaluation section for additional information.|
|8.||Why was this (Superfund) process accelerated?|
|The policy decision by EPA to accelerate the Superfund process is unknown to SEE. However, the acceleration is not the result of new information or a change in the health impact of the sitecontaminants.|
|9.||Will the public health assessment completed in two weeks properly assess the site?|
|Enough data is available to make recommendations which will protect residents' health. This assessment is a dynamic document and will continuously be updated as additional informationbecomes available.|
|10.||Would a dairy operating near the site be affected by the contamination from the site?|
|It is unlikely that contamination from the site could have affected a dairy. Additionalinvestigations regarding off-site contamination will be recommended to collect enoughinformation to address this concern.|
|11.||Could the residential areas on Cedar Drive using private wells be affected?|
|Information on private wells regarding the number, depth, and distance of these wells from the site is not available at this time. However, if residents on Cedar Drive are not receiving theirdrinking from the shallow aquifer (20-25 foot depth), their wells should not be affected by sitecontaminants.|
|12.||Will the cleanup remove enough soil to eliminate the contamination?|
|The remediation process selected should eliminate any possible health impact from on- site contamination on the local population.|
|13.||Are there drums buried on the site?|
|There are gas storage tanks known to exist on the site.|
|14.||Is anyone going to investigate contaminants in the air?|
|EPA has sampled the air for site contaminants and has found none. However it is recommended that continuous air monitoring should take place during remediation activities.|
|15.||Can these contaminants cause autoimmune diseases, neurological problems, lupus, multiple sclerosis (MS), or demyelinating polyneuropathy, or fibrositis?|
|Site contaminants are not known to cause autoimmune diseases, lupus, MS, demyelinating polyneuropathy, or fibrositis. There is suggestive evidence that benzene and chlorinated dioxinscan be harmful to the immune system and animal studies indicate that pentachlorophenol couldhave adverse effects on the nervous system.|
|16.||Is there a danger from exposure to contaminated sediment?|
|Exposure to contaminated sediments are not likely to cause adverse health effects, however SEE recommends individuals not to trespass onto the site. Please refer to the Toxicological Evaluation section for additional information concerning sediment and health effects.|
|17.||Is there a danger from eating fish or crawfish from Dugdemona River?|
|This information is not available at this time. It is recommended that off-site sampling of aquatic biota be conducted to determine the answer to this question.|
|18.||Was there exposure from the municipal water leak near the site?|
|Adequate information regarding this leak is not available to answer this question. It will be recommended that a more in-depth investigation be made in order to collect adequate informationto address this concern.|