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1. ATSDR > Public Health Assessments & Consultations

The Tables in this section list the contaminants of concern. These contaminants are evaluated in the subsequent sections of the health assessment and a determination is made as to whether exposure to them has public health significance. The Section of Environmental Epidemiology selects and discusses these contaminants based upon the following factors:

1. Concentrations of contaminants on and off the site.

2. Field data quality, laboratory data quality, and sample design.

3. Comparison of on-site and off-site concentrations with health assessment comparison values for (1) noncarcinogenic endpoints and (2) carcinogenic endpoints.

4. Community health concerns.

In the data Tables that follow under the On-site Contamination subsection and the Off-site Contamination subsection, the listed contaminant does not mean that it will cause adverse health effects from exposure. Instead, the list indicates which contaminants will be evaluated further in the public health assessment. When selected as a contaminant of concern in one medium, that contaminant 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 that are used to select contaminants for further evaluation. These values include Environmental Media Evaluation Guides (EMEGs), Cancer Risk Evaluation Guides (CREGs), and other relevant guidelines. CREGs are estimated contaminant concentrations based on one excess cancer in a million 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 unlikely to cause adverse health effects.

A. On-site Contamination

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 the Remedial 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:

1. former process area
   
2. former impoundment area
   
3. drainage area north and northeast of the process area
   
4. portion of the site north of Creosote Branch
   
5. southern portion of the sit
   
6. office area west of Creosote Branch

The contaminated surface soil samples are in the former process area, impoundment areas, the drainage 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. Table 1 reports the contaminants and their concentrations.

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 18 boreholes. Samples were taken at about 0-20 feet. Figure 1.2 and 1.3 illustrate subsurface soil sampling locations. Tables 2.1 and 2.2 report the contaminants and concentration ranges. The portions of the site for which subsurface soil data exist include:

1. former process area
   
2. former impoundment and drainage area northeast of the process area
   
3. tarmat area
   
4. waste cell constructed during the removal action
   
5. southern portion of the site
   
6. portion of the site north of Creosote Branch

ppb - parts per billion

ppb - parts per billion

Surface Water

EPA collected 6 surface water samples at different locations illustrated in (Figure 1.2 and 1.3):

1. Creosote branch upstream
   
2. a ditch upstream of the site
   
3. pond on the site
   
4. Creosote branch downstream of the site drainage ditches
   
5. Creosote branch in the northwest portion of the site, upstream of the confluence with an unnamed tributary and with the majority of the site drainage ditches.

The contaminant detected in these samples was PCP. Table 3 reports the contaminant and its maximum concentration.

ppb - parts per billion

The pond has a surface area of approximately 0.5 acres, and a depth of eight feet. It was constructed as a reservoir for storage of fire protection water.

Sediments

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.

ppb - parts per billion

Ambient Air

During our site visit we could detect a heavy smell of creosote all over the site even at the gate entrance. Air sampling data was not available, however, it was reported that previous investigations 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 in soil and subsurface soil. Wells screened at 5 to 20 feet were reported to contain one foot of floating creosote and several inches of floating oils.

EPA did on-site sampling of four deep and seven shallow monitoring wells both up and down gradient of the contaminated portions of the site. The shallow monitoring well boreholes were screened 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 zone approximately 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 discharges into Creosote Branch along the northern and western site boundaries. Flow direction within most of the site is to the north towards Creosote Branch. Shallow and deep potentiometric surfaces reveal 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.

ppb - parts per billion

Deep monitoring wells installed to the east (MW-3), west (MW-2) and north (MW-7) of the former process area show no contamination. Analysis of groundwater data from the shallow monitoring wells reveals contamination with PAHs, B(a)P, benzene and phenols. Samples collected from deep monitoring wells (depth 55-65 feet) contained no detectable contamination.

Biota

EPA did an ecological exposure assessment which showed that the site is currently posing a threat to the aquatic environment because of potential effects of contaminated surface water, soil, and sediment from the American Creosote site (6).

Biota sampling was attempted but no fish were caught (8), therefore, no data are available.

B. Off-site Contamination

Off-site sampling of soil, surface water, air, or biota was not conducted.

Air

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.

Sediment

Three sediment samples were collected downstream of the site. SD-7 is nearly a mile down stream of the site. Sediments samples SD-9 and SD-10 were collected from Creosote Branch approximately 6,300 feet and 10,000 feet downstream of the site. Table 6 reports the contaminants and their concentrations.

ppb - part per billion.

Groundwater (Public Supplies)

EPA collected a ground water sample from a nearby municipal drinking water supply well belonging to the Red Hill Water Cooperation (Figure 1.6). This well is off the site approximately one mile from the site on Highway 167, approximately 200 yards north of Creosote Branch. It is screened from approximately 550 to 600 feet in the Sparta sand. The only compounds detected in the sample from this well were PAHs (acenaphthene, fluorene) but the levels did not exceed comparison values. A resample of this well indicated no PAHs or phenol.

Biota

Biota sampling was attempted but no fish were caught (8), therefore, no data are available.

Surface Water

Bioassays were conducted on sediment and surface water along 2 miles of Creosote Branch, however, no surface water data were located.

C. Quality Assurance and Quality Control

The analysis and conclusion presented in this public health assessment are based on data contained in the RI/FS study submitted to EPA. The availability of the conclusions drawn are determined by the accuracy and reliability of the referenced information. The contractor at this site, upon review of the data analysis, states that all the data are acceptable and reliable.

D. Physical and Other Hazards

The site is fenced, however a rusty pressure vessel labeled "hazardous waste inside" and several drums on the site represent physical hazards, especially to trespassing children. The vessel did contain 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, the Section of Environmental Epidemiology evaluated the environmental and human components that lead to human exposure. This pathways analysis consists of five elements: A source of contamination, transport through an environmental medium, a point of exposure, a route of human exposure, and an exposed population.

ATSDR categorizes an exposure pathway as a completed or potential exposure pathway if the exposure pathway cannot be eliminated. Completed pathways require that the five elements exist and indicate that exposure to a contaminant has occurred in the past, is currently occurring, or will occur in the future. Potential pathways require that at least one of the five elements is missing but could exist. An exposure pathway can be eliminated if at least one of the five elements is missing and will never be present. Only those pathways that are important and relevant to the site will be discussed.

A. Completed Exposure Pathways

On-Site Soil

Past, and possibly current and future, exposure pathways are likely from contact with contaminated on-site surface soil. Incidental soil ingestion and dermal contact are considered routes of exposure, particularly for workers on the site who are involved in remediation, and for residents who trespass the site, particularly children. It is documented that children used the site as a ballfield and playground. In addition, prior to 1988 the site was not fenced and local residents, including school children, frequently crossed it on a trail that extended from the site access road to the residential street that forms the southeast site boundary.

Sediment

Past, and possible current and future, exposure to contaminated sediments are likely from the use of Creosote Branch. Past exposure through dermal contact, and possibly ingestion, exists because children that were interviewed on the site prior to fencing claimed to have regularly swam in Creosote Branch. Present and future exposure exists for those who trespass the site or use Creosote Branch for recreational activities.

Surface Water

Past, and possibly present and future, exposures are likely to occur from contact with surface water contamination in Creosote Branch. Surface water run-off from American Creosote drains into Creosote Branch, which bounds the site to the west and crosses the northern portion of the site. The drainage ditches that traverse the site receive surface water runoff from the process area and subterranean seepage of creosote wastes that appear to have infiltrated into the soil. Pools of these liquids collect in the bottoms of the ditches and are washed into Creosote Branch by rainfall runoff. Residents, particularly children, who use Creosote Branch for recreational activities are likely to get exposed through dermal contact and incidental ingestion.

Air

This exposure pathway is considered complete based on the experience of the Section of Environmental Epidemiology and DEQ who reported a heavy smell of creosote on the site during our site visit. Past, present, and probably future exposure to contaminated ambient air is likely for residents trespassing the site and remediation workers. Prior to 1988 the site was not fenced and local residents, including school children, frequently crossed it on a trail that extended from the site access road to the residential street that forms the southeast site boundary.

Facility Workers

According to reports from individuals who previously worked at the American Creosote facility and 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 not measured, therefore, no estimate of actual exposures can be made.

B. Potential Exposure Pathways

Hazardous waste Workers

Site investigation and remediation workers who fail to follow the Occupational Safety and Health Administration (OSHA) personal protection regulations are at risk of exposure when in contact with the contaminated media described previously.

Off-Site Soil

Residential neighborhoods are present in all directions from the site. The closest are the seventeen houses bordering the site. There is a housing development that lies to the south of the American Creosote site along Mcleod and Watts Streets (Figure 1.3). Potential exposure to contaminants could occur because of several environmental transport mechanisms. These mechanisms 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.

Sediment

Contaminated sediments were detected on the site and off the site at the Creosote Branch which joins with Port Du Luce Creek. It was reported that the sediment samples taken along 2 miles of Creosote 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.

Surface water

Contaminated surface water was detected in Creosote Branch which empties into Port Du Luce Creek. Like off-site sediments, it was reported that the surface water samples taken along 2 miles of Creosote Branch appear to be uncontaminated (8). Surface water 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. Residents do use Port Du Luce Creek for recreational activities.

Biota

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 Dugdemona River are contaminated and eaten. Contaminants leaching into the site's drainage ditches will empty into the Creosote Branch. There are various species of fish, crawfish, and other wildlife living in various locations along Creosote Branch adjacent to and upstream of the site. Residents and children use these points of exposure for recreational activities. There is no commercial agriculture or livestock production/grazing on areas of visible contamination, however hunting game does occur in this area.

Fugitive Dust

Dust clouds have been reported on the site. Since the site is open, flat, and only sparsely vegetated, there exists the threat from contaminated particulates during dry, windy period to residents of the seventeen houses bordering the site.

Groundwater (Public Water Supply)

According to information on file at Louisiana Department of Transportation and Development, 12 water wells are within a one mile radius of the site. The depth ranges from 480-600 feet. Of these 12 wells, three are public water supply, three are abandoned public water supply, five are test wells, and one is an observation well. Groundwater in the site area is found in two separate aquifers. Wells screened in the shallow aquifer (5-30 feet deep) on the site were found to contain contaminants similar to those found in soil and subsurface soil. Thus, downward migration of the contaminants is occurring but it may not reach the deep aquifer because beneath the shallow aquifer is 20 feet of relatively dry interbedded silty sands and silty clays that appear to be contiguous across the area. These layers, in addition to the upward gradient or artisan effects of the lower groundwater may act to decrease the downward movement of contaminants to the next lower aquifer at 55 to 65 feet deep. Groundwater from these aquifers is not used in the vicinity of the site as a drinking water source.

Residential Wells

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 does migrate off the site and residential wells were installed within the contaminated area or if the shallow aquifer is used as a source of potable water. The potential receptor population would be future users of new wells.

A. Toxicological Evaluation

Introduction

This section will discuss the health effects in persons exposed to specific contaminants, evaluate state and local health databases, and address specific community health concerns. To evaluate health effects, ATSDR has developed minimal risk levels (MRLs) for contaminants commonly found at hazardous waste sites. The MRL is an estimate of daily human exposure to a contaminant below which non-cancer, adverse health effects are unlikely to occur. The MRLs are developed for each route of exposure, such as ingestion and inhalation, and for length of exposure, such as acute (14 days or less), intermediate (15 to 364 days), and chronic (365 days or greater). The ATSDR presents these MRLs in Toxicological Profiles. These chemical specific profiles provide information on health effects, environmental transport, human exposure, and regulatory status. When MRLs are not available, reference doses (RfD) provided by the EPA are evaluated. For carcinogenic substances, EPA has established the Cancer Slope Factor (CSF) as a health guideline. The CSF is used to determine the number of excess cancers expected from exposure to a contaminant.

The health effects which result from the interaction of an individual with a hazardous substance in the environment depend on several factors. One is the route of exposure: that is, whether the chemical is breathed, consumed incidentally in contaminated soil or sediment or eaten in contaminated food or water, or contacts the skin. Another factor is the dose to which a person is exposed and the amount of that exposure dose that is actually absorbed. Mechanisms by which chemicals are altered in the environment, or inside the body once absorbed are also important. A great deal of variation exists among individuals.

The following toxicological evaluation will evaluate the potential for adverse health effects from the previously discussed Completed Exposure Pathways section. Potential exposure pathways lack sufficient information for further evaluation. According to community reports, worker exposure 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 on the site has occurred. Again, the absence of data prohibits an estimation of exposure doses and potential health effects.

SEE has reviewed the toxicological profiles for chemical substances of concern at the American Creosote site. These documents interpret health effects information on the substances and specify the level at which people might be harmed.

Polycyclic Aromatic Hydrocarbons

Polycyclic aromatic hydrocarbons (PAHs) are a class of structurally related compounds. As a group, these compounds have similar characteristics.

Exposure to PAHs through incidental ingestion and dermal contact with contaminated surface soils and sediments may have occurred and may still be occurring on the site among workers and trespassers, particularly children. Off-site sediments are also a source of exposure to PAHs for residents and workers. Persons could potentially be exposed to PAHs through consumption of contaminated fish or game animals in the vicinity of the site, but biota samples are not available for evaluation. Using the highest total PAH concentration detected in on-site surface soil (208.9 ppm), the ingestion exposure for adults and older children does not exceed ATSDR's acute MRL of 0.1 mg/kg/day for benzo(a)pyrene and other PAHs. Using the highest total PAH concentration detected in off-site sediment (6.81 ppm), the ingestion exposure for younger children (1 year through 6 years of age) who have pica habits does not exceed the acute oral MRL. That MRL is based on an animal study in which developmental effects were seen in the offspring of mice following in utero exposure to benzo(a)pyrene. In determining the exposure doses, we assumed that a pica child ingests 5000 mg of soil per day; that a non-pica child ingests 500 mg of soil per day, and that adults ingest 100 mg of soil per day. Neither ATSDR nor EPA have developed chronic health guidelines, i.e., MRLs and RfDs, for the PAHs. Generally it can be assumed 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. The levels of PAHs at which those effects were first seen are orders of magnitude higher than the estimated dose for younger children. Therefore, the maximum level of PAHs found in the on-site soil 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 from exposure 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 of contaminated soil. For the off-site sediment exposure, we estimate an insignificant increased cancer risk. This is based on the assumption that a person is exposed 5 days a week, 50 weeks a year 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 to determine the health effects from skin exposure. Adverse skin effects have been noted in animals with acute and subchronic dermal exposures to PAHs. Those effects include destruction of sebaceous 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 to sunlight may result in phototoxic effects such as erythema (redness of the skin), urticaria (elevated patches of skin), and burning and itching. Persons with pre-existing skin conditions may be more 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 caused tumors in laboratory animals through ingestion, skin contact, and inhalation. Epidemiologic studies of workers occupationally exposed to PAHs have provided limited evidence that PAH exposure may contribute to increased incidence of skin, lung, and genitourinary cancers. The most likely exposure routes in the occupational settings were through inhalation and skin contact with those compounds. Although inhalation of contaminated dusts is possible on the site and in the residential areas, potential health effects cannot be evaluated without air sampling data.

Pentachlorophenol

Exposure to pentachlorophenol has probably occurred to trespassers and workers via ingestion and dermal exposure to PCP contaminated on-site surface water and soil. The highest levels of pentachlorophenol 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 intermediate oral MRL of 0.001 mg/kg/day for pentachlorophenol. Based on the soil ingestion rates for adults and children discussed under PAHs and the highest levels of pentachlorophenol found, the ingestion exposures to on-site soil for adults and children do not exceed ATSDR's acute and intermediate MRLs. The estimated exposed doses for ingested on-site surface water for children does exceed the intermediate MRL and slightly exceeds the acute MRL. Adult exposure doses do not exceed either MRL. EPA's RfD of 0.03 mg/kg/day is not exceeded by either the child or adult estimated exposure doses.

Animal studies have indicated that long-term exposure (greater than 14 days) to low levels of pentachlorophenol can have adverse effects on the liver, kidney, nervous system, and immune system. Studies have also indicated that long-term exposure to low levels of pentachlorophenol encountered 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 unlikely to result in those adverse health effects.

ATSDR could not locate any adequate studies that described significant levels of skin exposure to pentachlorophenol. Occupational exposures to pentachlorophenol have been associated with severe skin eruptions. Nonoccupational exposures to wood treated with pentachlorophenol have been associated with pemphigus vulgaris (a serious skin disease characterized by blisters and loss of 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 from the manufacture of this chemical (10). The toxic dermal effects of pentachlorophenol appear to be most serious following high-dose, acute exposure.

Sufficient evidence exists from animal studies to suggest that pentachlorophenol might cause cancer in humans. No convincing evidence has been obtained from human epidemiological studies that indicate that pentachlorophenol causes cancer in humans. Case reports suggest a possible 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 highest PCP concentration in on-site soil and surface water , we estimate there to be no increased risk of cancer from incidental ingestion of contaminated soil and a low to moderate increased cancer risk from the ingestion of the on-site surface water. The soil scenario is based on the assumption that a person is exposed 5 days a week, 50 weeks a year for 30 years and incidentally ingests 50 mg of soil per day. The surface water scenario is based on the assumption that a person ingests 1 liter of water 5 days a week for 30 years.

Chlorinated Dioxins

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 concentration of 5.32 ppb in on-site surface soil. It was also detected in lesser concentrations in subsurface soils. A maximum concentration of 0.01 ppb was detected in on-site sediment. Trespassers and workers probably were exposed to the contaminated surface soil and sediment through incidental ingestion and dermal contact.

ATSDR has set an acute MRL of 0.0000001 mg/kg/day and an intermediate and chronic MRL of 0.000000001 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 for 2,3,7,8-TCDD. Estimated ingestion exposures for adults exceed the chronic oral MRL but not the acute MRL. The maximum on-site surface soil concentration does exceed ATSDR's level of concern of 1 ppb for residential soils, however, the sample was taken from the Process Area of the facility and does not reflect similar exposure conditions as residential soils. As stated in the Pathways Analysis, off-site soil were not sampled.

Animal studies have indicated that 2,3,7,8-TCDD may cause liver damage; severe loss of body weight; damage to the immune system, and adverse reproductive effects including spontaneous abortions and malformations in animal offspring. Adverse effects of that chemical on the immune system, reproductive system and developing fetuses have not been found in humans, but some evidence has suggested that 2,3,7,8-TCDD might cause liver damage, weight loss, and digestive disorders in humans. Chloracne is the only confirmed effect in humans produced by certain compounds contaminated with 2,3,7,8-TCDD. Chloracne is a skin disease characterized by blackheads, cysts, pustules, and inflammatory (pain, redness, and swelling) skin changes of varying degrees of severity. A minimum toxic dose of 0.0001 mg/kg has been suggested to produce adverse noncancer health effects in humans (13). Although the ingestion exposures for children equal the acute MRL for 2,3,7,8-TCDD and the ingestion exposures for children and adults exceed the chronic MRL for this chemical, all estimated exposures are well below the 0.0001 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-TCDD found on the site. Results from animal studies clearly indicate that 2,3,7,8-TCDD causes cancer in laboratory animals. Several epidemiological studies of human populations exposed to herbicides contaminated with 2,3,7,8-TCDD have shown an association with cancer that included an increased incidence of soft tissue sarcomas, lymphomas, and stomach cancer. The evidence from human epidemiology studies is not conclusive because of inadequate exposure information and concomitant exposures to other chemicals. Other epidemiological studies have found no association 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.

B. Health Outcome Data Evaluation

Communities near the site are very concerned with the health effects including cancer of the contaminants found in the site.

Adequate cancer incidence data are not available at this time for Winn Parish. However, cancer mortality 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 by site, address, age, race and sex for the state of Louisiana. A ratio of average age adjusted death rates between 1989-1991 and 1979-1981 in Winn parish was calculated. No statistically significant 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 Parish and 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

C. Community Health Concerns Evaluation

The following is a list of questions posed by residents of Winnfield, Louisiana during the public meeting 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. The municipal water supply wells are much deeper at depths of 480-600 feet. Downward migration of the contaminants from the shallow aquifer is occurring but it may not reach the 55-65 foot aquifer because beneath the shallow aquifer is 20 feet of relatively dry interbedded silty sands and silty clays that appear to be contiguous across the area. These layers, in addition to the upward gradient or artisan effects of the lower groundwater may act to decrease the downward movement of contaminants to the next lower aquifer at 55 to 65 feet deep. A potential exposure to contaminated groundwater would be possible if private wells were installed within groundwater where 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 unreported private wells. If any citizen has a private well screened in the contaminated shallow aquifer, they should request to have their water tested and, based on the results, may look for alternate water supplies. 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 leukemia but was not found in completed exposure pathways. Pentachlorophenol and dioxin are both probable human carcinogens. Please refer to the Toxicological Evaluation section for additional information.
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 site contaminants.
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 information becomes 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. Additional investigations regarding off-site contamination will be recommended to collect enough information 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 their drinking from the shallow aquifer (20-25 foot depth), their wells should not be affected by site contaminants.
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 dioxins can be harmful to the immune system and animal studies indicate that pentachlorophenol could have 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 information to address this concern.

Agency for Toxic Substances and Disease Registry, 1825 Century Blvd, Atlanta, GA 30345
Contact CDC: 800-232-4636 / TTY: 888-232-6348 

Department of Health and Human Services