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PUBLIC HEALTH ASSESSMENT

VIENNA TETRACHLOROETHENE
VIENNA, WOOD COUNTY, WEST VIRGINIA


SUMMARY

The Vienna Tetrachloroethene site, also known as the Vienna Cleaners site, is located in a lightcommercial and residential area of downtown Vienna, Wood County, West Virginia. The city ofVienna lies in a valley along the eastern bank of the Ohio River. The Vienna Cleaners facility issituated one block northwest of the Vienna City Hall and is surrounded by private businesses andsingle family dwellings. Dry cleaning operations were conducted at the Vienna Cleaners facilityfrom the late 1940's until the mid-1990's . Past practices at the cleaner included pouring wastetetrachloroethene (PCE), a dry cleaning solvent, on the ground behind the facility. Spills of PCEfrom outdoor aboveground solvent tanks were also reported. The quantity of waste PCE disposed ofat the Vienna Cleaners is not known.

Former workers at the cleaners and residents that lived within about a one block radius of the sitewere likely exposed to PCE in on-site and off-site soil. In addition, PCE contamination from thissite migrated into four city wells. ATSDR estimates that for less than one year, PCE - contaminateddrinking water was provided to Vienna residents. The contaminated wells were closed in 1992.

Based upon data reviewed and observations made, the Vienna Tetrachloroethene Superfund Site is currently categorized by the Agency for Toxic Substances and Disease Registry (ATSDR) as a Public Health Hazard. The available data shows that humans were likely exposed to low levels of PCE and TCE in the past from soil and ground water contamination and could potentially be exposed to PCE and TCE in the future if the ground water plume reaches the municipal water wells currently in operation at levels that could cause adverse health effects. Current scientific literature suggests that prolonged exposure to PCE and TCE may increase an adult's chance of having a stroke and developing liver or kidney cancer. Limited scientific evidence also suggest that children exposed as fetuses to PCE and TCE may have an increased chance of being born and diagnosed (at the time of birth or shortly there after) with birth defects (e.g., central nervous system defects, neural tube defects, and oral cleft defects). However, the concentrations of PCE and the duration of exposures at the Vienna Cleaners were less than what was seen in these studies.


BACKGROUND

In this public health assessment, the Agency for Toxic Substances and Disease Registry (ATSDR),evaluates the public health significance of the proposed Vienna Tetrachloroethene NationalPriorities List (NPL) site in Vienna, Wood County, West Virginia. ATSDR has reviewed availableenvironmental and health outcome data and community health concerns to determine whetheradverse health effects are possible. In addition, this public health assessment recommends actions toreduce, prevent, or identify more clearly the possibility for site-related adverse health effects. ATSDR, in Atlanta, Georgia, is one of the agencies of the U.S. Public Health Service. TheSuperfund law (Comprehensive Environmental Response, Compensation, and Liability Act of 1980[CERCLA] as amended by the Superfund Amendments and Reauthorization act of 1986 [SARA])requires ATSDR to conduct public health assessments of hazardous waste sites within 1 year of thesite's proposal to the NPL. On April 23, 1999, the Environmental Protection Agency (EPA)proposed the Vienna Tetrachloroethene site be considered for the NPL.

A. Site Description and History

The Vienna Tetrachloroethene NPL site is located in an urban residential and commercial areasurrounding the City of Vienna Municipal Building and Vienna Cleaners. The City of Vienna islocated in Wood County, West Virginia, and lies in a valley along the eastern bank of the OhioRiver. The Vienna Cleaners facility is located one block northwest of the Vienna MunicipalBuilding and is surrounded by private businesses and single family dwellings. Dry cleaningoperations were conducted from the late 1940's until the mid 1990's (1).

Vienna's public water supply system supplies everyone's drinking water in the city. Six of Vienna's12 municipal wells, located in the direct vicinity of the Vienna Cleaners facility, were taken off-lineon June 11, 1992 because elevated levels of tetrachloroethene (PCE) contamination were detected. The Vienna Water Department began testing for volatile organic chemicals (VOCs) in the city waterdistribution system in 1988, to comply with new requirements of the1986 Safe Drinking Water ActAmendment. From 1988 through 1990, no PCE was detected in the city water distribution systemduring testing for VOCs within a one mile radius of the Vienna Cleaners facility.

In April and September of 1991, PCE with levels of 64 parts per billion (ppb) and 20 ppbrespectively were detected at a business and residence. In February 1992, Municipal Wells 1-4located in the vicinity of the City Hall had the highest PCE concentrations ever detected during theroutine testing for VOCs. Levels of 170, 390, 8 and 7 ppb were detected respectively in wells 1-4(2). On June 11, 1992, the city discontinued use of wells 1-4 because of these elevated levels. Based on results of PCE testing, ATSDR estimates that people were exposed to PCE contaminationwithin a one year time period from 1991 to 1992. The EPA used emergency funds to build two newmunicipal wells which were brought on-line in March of 1997 (2).

The water distribution system for the city is not zoned. When water leaves the supply wells it isblended through chlorine contact chambers for thirty minutes. Booster pumps are used to pump thewater from the water wells into the distribution system at a rate of 600 hundred gallons per minute. Since 1988, the water system has been sampled once a month for VOCs by the Vienna WaterDepartment and is also tested by the West Virginia Department of Natural Resources (WVDNR).

Past disposal practices at the cleaners included pouring waste PCE, on the ground behind the site. PCE spills from outdoor aboveground solvent storage tanks also occurred. The site is classified as asmall quantity generator by the West Virginia Department of Environmental Protection under theResource Conservation and Recovery Act (RCRA) (1). Elevated levels of PCE have been detectedin surface and subsurface soils at the site, in ground water beneath the site, and in the city sewers near the site (See Appendix C).

B. Site Visits

On March 29, 2000, representatives from ATSDR and EPA visited the site and the city of Vienna. The source of the PCE contamination emanated from the Vienna Cleaners site, which is no longeroperational.

That same day, representatives from ATSDR conducted a public availability meeting andinterviewed citizens in Vienna. A total of eighty-two citizens attended the meeting (8). The citizenshad concerns and questions about various illnesses identified in the community and the possibility ofthe illnesses being attributed to PCE exposure. Representatives attempted to answer questions andrecorded concerns so they could be addressed in the health assessment.

C. Demographics, Land Use, and Natural Resource Use

Approximately 7,657 people live within a one mile radius of the site. The racial mixture is asfollows: 7,592 Whites, 33 Blacks, 25 Asians, 13 Latinos, 4 American Indians, and 2 other (4).

Vienna has 11,000 residents and 14,500 residents overall that rely on the city's eight activemunicipal wells for their water supply (1). The land surrounding the site is mostly commercialbusinesses, urbanized residences and the Vienna Municipal Building . The depth to ground water in the vicinity of the city hall building and the cleaners is 55 feet (3).


ENVIRONMENTAL CONTAMINATION AND OTHER HAZARDS

ATSDR has evaluated all of the available environmental monitoring data to determine whatenvironmental contaminants and which specific areas on the site may be a concern. Comparisonvalues (CV) were used to determine which contaminants should be examined more closely. A CV isa health-based threshold below which no known or anticipated adverse effect on the health ofpersons should occur. CVs allow an adequate margin of safety. The contaminant tables inAppendix C identify the CVs for each contaminant. Appendix A contains definitions of CVs usedin this public health assessment.

A contaminant is evaluated further if the contaminant level in a valid environmental sample exceedscomparison values. The presence of a chemical in the contaminant tables does not mean thatexposures to the contaminant or adverse health effects have occurred or will occur. Later sections ofthis public health assessment contain more detailed discussions of the potential for adverse humanhealth effects as a result of any exposures to the selected contaminants. This document focuses onthose contaminants which posed a reasonable potential for human exposure.

A. On-Site Contamination

In 1993, during soil gas monitoring at the site, EPA detected PCE and trichloroethene (TCE) atlevels above the CV. PCE and TCE were detected at maximum concentrations of 28,000 ug/L and710 ug/L The chemicals are identified in Table 1, Appendix C, and further evaluated in the pathway analysis section.

In 1993, EPA collected subsurface soil samples (6"-12") on-site and analyzed for volatile organic chemicals (VOCs). PCE and TCE were detected in subsurface soils at levels above the CV. PCEand TCE were detected at maximum concentrations of 190,000 ppb and 470 ppb. The chemicalsare identified in Table 2, Appendix C, and further evaluated in the pathway analysis section.

B. Off-Site Contamination

In 1992, drinking water was collected from the public water supply wells #1 through #4 at the wellsite and analyze for VOCs. The VOCs detected were above the CV. PCE detected in well #2, (390ppb) had the highest maximum concentration in a contributing well to the drinking water municipalwell system. These chemicals are identified in Table 3, Appendix C, and further evaluated in the pathway analysis section.

In 1997, surface soil was collected from soil boring sample #4 at the well field site and analyzed for VOCs. The VOCs detected equaled the CV. PCE was detected at a maximum concentration of20,000 ppb in the surface soil. These chemicals are identified in Table 2, Appendix C, and further evaluated in the pathway analysis section.

In 1997, ground water was collected from soil boring samples #2 and #8 at the well field site and analyzed for VOCs. The VOCs detected were above the CV. PCE and TCE were detected atmaximum concentrations of 34,000 ppb and 65 ppb in the ground water. These chemicals areidentified in Table 3, Appendix C, and further evaluated in the pathway analysis section.

C. Physical and Other Hazards

The Vienna Cleaners is no longer in operation and the physical structure of the building is verysound and appears to present no safety hazards. No property boundary signs were identified duringthe site visit and no signs of trespassing were noticed during the site visit.


PATHWAY ANALYSIS

This section presents evaluations of the possible environmental pathways that help determinewhether individuals have been, are being, or will be exposed to site-related contaminants. Environmental pathways can be completed or potential. A completed pathway indicates that humanexposure to contaminants has occurred in the past, is occurring, or will occur in the future (9). Apotential exposure pathway indicates that human exposure to contaminants could have occurred inthe past, could be occurring, or could occur in the future. An exposure pathway can be eliminatedfrom consideration if exposure has never occurred and never will occur. If there is uncertainty aboutthe site relatedness of the contaminants of concern in an exposure pathway, the pathway will be evaluated as if the contaminants were related.

A. Completed Exposure Pathways On-site

Completed On-Site Subsurface Soil Exposure Pathway

Table 1 (Appendix D) lists the components of the completed environmental exposure pathway foronsite soil. Data sampling collected from the Vienna Cleaners site showed elevated levels of PCEand TCE in the soil. This pathway is considered completed because exposure to PCE and TCE atlevels above the comparison value (CV) occurred or could occur from contact with subsurface soil. The possible health impact of this completed exposure pathway is evaluated in the Public Health Implications Section.

Completed On-Site Air Exposure Pathway

Table 1 (Appendix D) lists the components of the completed environmental exposure pathway foronsite air, based on soil gas monitoring. Data sampling collected from the Vienna Cleaners showedelevated levels of PCE and TCE in soil gas and is considered complete, even though no ambient airdata is available. This is because exposure to PCE and TCE at levels above the CV may haveoccurred in the past from inhalation of soil gases when the site was operational. The possible healthimpact of this completed exposure pathway is evaluated in the Public Health Implications Section.

B. Completed and Potential Exposure Pathways Off-site

Completed Off-Site Drinking Water Exposure Pathway

Table 2 (Appendix D) lists the components of the completed environmental exposure pathway foroff-site drinking water. Ground water sampling from off-site showed elevated levels of PCE andTCE at the Vienna Oil Refinery and the Vienna municipal well field sites. Drinking water samplesfrom the tap confirmed that the contaminants entered the city of Vienna's drinking water supplysystem. The pathway is considered completed because exposure to PCE and TCE at levels abovethe CV occurred from drinking and having contact with drinking water. The possible health impactof this completed exposure pathway is further evaluated in the Public Health Implications Section.

Completed Off-Site Surface Soil Exposure Pathway

Table 2 (Appendix D) lists the components of the completed environmental exposure pathway foroff-site surface soil. Surface soil sampling from off-site showed elevated levels of PCE in thesurface soil. The pathway is considered completed because exposure to PCE at levels equal to theCV occurred. The possible health impact of this completed exposure pathway is further evaluated in the Public Health Implications section.

Future Potential Exposure

If remediation of the site is not completed, the PCE and TCE contamination from the shallowground water plume that supplies drinking water to the remaining on-line wells in the surroundingarea of the City of Vienna could become contaminated. The plume is located in the vicinity of 29thSt. and Grand Central and 30th St. and Grand Central and emanates from the source at the ViennaCleaners and appears to be migrating in the northwest direction towards active municipal wells #7and #8. However, this plume is moving slowly and EPA plans to monitor groundwater upgradient from municipal wells #7 and #8 on a quarterly basis.


PUBLIC HEALTH IMPLICATIONS

A. Toxicological Evaluation

This section covers the potential health hazard from exposure to specific contaminants inenvironmental media, including ground water, soil, air, and biota.

To evaluate potential health effects, the Agency for Toxic Substances and Disease Registry(ATSDR) has developed minimum risk levels (MRLs) for contaminants commonly found athazardous waste sites. The MRL, similar to the reference dose (RfD) of the EnvironmentalProtection Agency (EPA), is an estimate of daily human exposure to a contaminant below whichnon-cancer, adverse health effects are unlikely to occur (4). In the health assessment, we estimatedthe dose of a contaminant to individual persons and compared the dose at this site with ATSDR'sMRL or EPA's RfD. Any exposure dose below the appropriate MRL or RfD is unlikely to cause anon-cancer health hazard to humans. ATSDR presents the MRLs in toxicological profiles. Thesechemical-specific profiles provide information on health effects, environmental transport, humanexposure, and regulatory status. To address the health impacts of contaminants at this site, we usedthe toxicological information in ATSDR's toxicological profiles for tetrachloroethylene (PCE) and trichloroethylene (TCE).

TCE, as a degradation product of PCE, is usually less abundant than PCE is at this site. In soil gas,TCE concentration was less than 2.5% of the PCE concentration. In other environmental media atthis site, TCE concentrations were less than 0.2% of the PCE concentrations. TCE and PCE alsohave similar end points for the toxicological effects. Therefore, this evaluation will consider thecontaminants together.

1. Possible health effects for adults:

Tetrachloroethylene and Trichloroethylene

Elevated levels of PCE and TCE up to 390 ppb were found in drinking water supply wells in June1992, (as summarized Appendix C, Table 3), which were then closed. PCE and TCE were alsofound in the supply wells at lower concentrations (20-60 ppb). The actual PCE concentration in tapwater was expected to be less than that in the contaminated wells after the contaminated well waterwas mixed from other supply wells. In off-site ground water, elevated PCE levels up to 34,000 ppbwere also found (See Appendix C, Table 3). The subsurface soils contained up to 190 ppm of PCE,while surface soils contained 20 ppm (see Appendix C, Table 2). Additionally, PCE up to 28,000ug/m3 was found in soil gas at the site (see Appendix C Table 1).

Therefore, PCE exposure to residents occurred in the past. PCE may also diffuse from the soil gasinto the indoor air of an enclosed space. However, monitoring data on PCE in indoor air areunavailable. ATSDR concludes that residents were exposed to PCE and TCE in the past.

ORAL EXPOSURE:

Non-cancer health effects:

ATSDR staff estimated the amount of PCE and TCE (i.e., oral dose) that community members mayhave consumed from ingesting contaminated drinking water and surface soil at the site. Thecombined oral dose for PCE and TCE was then compared with the health guidelines to determinewhether this dose has the potential to effect people's health. Based on the worst case scenario that a10-kg child ingested one liter of the most contaminated potable well water and 200 mg of surfacesoil each day, the assessors estimated that the potential ingestion doses of the PCE and TCE fromcontaminated soil and supply well water to be 0.04 and 0.0004 mg/kg/day, respectively, in the past. Although the combined estimated dose in the past exposure did not exceed a short term healthguideline (ATSDR's acute MRL=0.05 mg/kg/day) for non-cancer effects, the estimated dose inslightly higher than the long-term guideline for PCE exposure (EPA's RfD.= 0.01 mg/kg/day). Therefore, the past exposure of ingested PCE may need to be evaluated further. The combined dosefrom potable water may double to 0.08 mg/kg/day if an additional dose from showering is included.

The potential dose (0.08 mg/kg/day) estimated from the most contaminated supply well, which wastaken out of service in 1992, was 125 times below the dose of 5 mg/kg/day observed to cause harmto baby mice (6). The mice exposed to high PCE doses in the animal test exhibited excessiveactivity at the age of 60 days. The community's past exposure to PCE at the 1992 levels in supplywells was less likely to pose significant health effects as compared to this animal study, because thedaily dose of PCE in drinking water was lower over a longer period of time than what the miceexperienced. In the animal test, the PCE in cooking oil was quickly delivered to the stomachs of themice thus allowing little time for the mice to eliminate the PCE out of their bodies before it reachedharmful levels in the body systems. In addition, the PCE concentration at tap water was most likelydiluted with clean water from other supply wells. Nevertheless, the highly contaminated PCE plume,up to 34,000 ppb, in ground water may migrate to other drinking water wells in the future, if thePCE plume is not confined or removed.

The potential doses from any garden produce are insignificant because PCE does not accumulate inbiota. The PCE concentration in private wells was not included in this calculation because noprivate wells are known to be used for drinking water consumption near this site. Based on theinformation available to ATSDR at this time, the PCE levels in the supply wells currently in serviceare not likely to cause any non-cancer diseases through water ingestion.

Cancer effects:

There is sufficient evidence to support that PCE and TCE, at very high doses, caused cancers inexperimental animals (11). Through the inhalation route, PCE and TCE caused liver cancer inmice; these liver cancers are hepatocellular adenoma and carcinoma in male mice and hepatocellularcarcinoma in female mice. In rats exposed to PCE and TCE in air, PCE and TCE caused(mononuclear cell) leukemia in both sexes and rare renal tubular cell neoplasms in male rats. Through the ingestion route, PCE and TCE caused liver cancer (hepatocellular carcinoma) in miceof both sexes.

The International Agency for Research on Cancer ( IARC) classifies PCE and TCE as Group 2Acarcinogens, which means that PCE and TCE are probably carcinogenic to humans. IARCconcluded that there were no adequate human data available to evaluate the carcinogenicity of PCEin humans (6, 11). Cancer effects of PCE and TCE have been studied in laundry and dry-cleaningworkers, who may also have been exposed to other petroleum solvents. Among these workers,excess incidence has been reported of the following cancers: lymphosarcomas, leukemia, andcancers of skin, larynx, colon, lung, urogenital tract, and urinary bladder. Although these studiessuggested a possible association between occupational exposure to PCE and TCE and increasedlymphatic malignancies, the evidence was inconclusive because the workers were also exposed topetroleum solvents.

The carcinogenic classification of PCE and TCE is under EPA review. In 1987, EPA's ScienceAdvisory Board (SAB), Office of Research and Development, placed PCE and TCE on thecontinuum between B2 (probable human carcinogen; based on sufficient evidence in animals andinadequate or no evidence in humans) and C (possible human carcinogen). In 1991, the SABreevaluated the animal cancer data and reiterated its 1987 position on the carcinogenicityclassification of PCE and TCE. This assessment is based on increased liver tumors in male andfemale mice, kidney tumors in male rats, and possibly mononuclear cell leukemia in male andfemale rats at very high doses. The SAB concluded that there is no compelling evidence of humancancer risk but it is prudent to reduce unnecessary human exposure to PCE and TCE. In response tothe on-going evaluation, the cancer potency factor for PCE and TCE and the associated unit risk fororal and inhalation exposure have been withdrawn (6).

If the PCE and TCE in undiluted water from the most contaminated supply well (390 ppb) wereactually consumed by the residents prior to 1992, then they are expected to receive an exposure dose(about 0.01 mg/kg/day) that was associated with "no apparent excess cancer risk." Thisconservative estimate is based on the assumption that a 70-kg man consumed 2 liters of water for alife time and ingested 100 milligrams (mg) of contaminated soil each day for his lifetime. Thisconservative estimate is based on the cancer potency factor that is currently under EPA review. Thecontaminated supply wells have been taken out of service since 1992. The estimated risk for excesscancer is even lower under the assumption that the exposure to PCE and TCE in supply wells islimited to the one year, from 1991-1992, rather than the lifetime of 70 years.

The highest concentration of PCE (up to 34,000 ppb) found in an offsite monitoring well is notbeing consumed by people. However, this plume could migrate into drinking water wells and causehealth problems if it is consumed by people.

INHALATION EXPOSURE:

ATSDR established a chronic MRL level of 0.04 ppm for PCE and TCE in the air. At this level,PCE and TCE are unlikely to cause neurological effects (e.g., dizziness, increased reaction time, andloss of color vision) or other non-cancer diseases. The PCE and TCE concentrations in the air at thissite has not been monitored although the concentration in soil gas was 28,000 ug/m3 (4.1 ppm) forPCE. EPA is reviewing the unit cancer risk of 0.0000005/ (ug/m3) for airborne PCE and TCE aftera life time of exposure.

The PCE and TCE concentrations in indoor air are unavailable. If the high level of PCE in soil gasis allowed to enter into indoor air space without sufficient dilution, this exposure has the potential tocause a high level of cancer risk. The PCE level in soil gas was only one order of magnitude lowerthan the concentration of 678,000 ug/m3 that caused significant rate of liver cancer in mice.

If the indoor concentration of PCE reached the level comparable to the 4.1 ppm in the soil gas, thenthe possibility of non-cancer adverse health effects becomes a health concern. This concentration isclose to the harmful concentration of 7.3 ppm that caused neurological effects such as the loss ofcolor vision in humans. At 10-20 ppm, PCE also caused dizziness and decreased reaction time inhumans.

DERMAL EXPOSURE:

Prior to 1992, city water contaminated with PCE & TCE was probably used for showering &bathing. No guideline is available for safe concentrations regarding dermal exposure to PCE andTCE in water. However, the absorbed dose of PCE and TCE in bathing water can be estimated andcompared to the safe dose in oral exposure. This approach for risk assessment results in anadditional uncertainty associated with the extrapolation of adverse health effects from oral exposureto dermal exposure.

In 1992, Bogen et al. estimated that a 70-kg man, immersing 80% of his body surface in diluteaqueous PCE solution conservatively for 20 minutes, would take up the amount of PCE equal tothat in 2 L of water (5). Thus, we estimate that the average dose might have been at 0.01mg/kg/day if a resident immersed in the water from bathing one hour a day, two days a week usingthe undiluted contaminated well water containing 390 ug/L of PCE. This estimated dose is farbelow the harmful oral dose of 5 mg/kg/day to the baby mice. This average dose from past dermalexposure, even added to the past oral exposure from drinking water, is unlikely to cause significantnon-cancer health effects to adults or children. As stated in the previous section for ingested dose,the equivalent dose of 0.001 mg/kg/day from dermal exposure to PCE is expected to pose "noapparent increased cancer risk" to people. The contaminated supply wells were taken out of service. Currently, the residents are not exposed to any PCE and TCE from city water, which is nowpumped from uncontaminated supply wells.

Past dermal exposure to PCE and TCE through showers is expected to be even lower than theexposure from bathing in bath tubs. The volatile PCE and TCE tend to evaporate into the air fromwater droplets under the shower head.

The PCE in the contaminated ground water plume, with PCE concentration up to 34,000 ppb, maysomeday reach other wells if the PCE plume is not confined or removed. The potential future dosefrom dermal exposure is estimated at 8.3 mg/kg/day. In animal tests, PCE at this dose level causedadverse effects in the development of young mice.

2. Children and Other Susceptible Populations:

ATSDR's Child Health Initiative recognizes that the unique vulnerabilities of infants and childrendemand special emphasis in communities faced with contamination of their water, soil, air, or food. Children are at a greater risk than adults from certain kinds of exposures to hazardous substancesemitted from waste sites and emergency events. They are more likely to be exposed because theyplay outdoors and they often bring food into contaminated areas. They are more likely to come intocontact with dust, soil, and heavy vapors close to the ground. Also, they receive higher doses ofchemical exposure due to lower body weights. The developing body systems of children can sustainpermanent damage if toxic exposures occur during critical growth stages.

The fetus is particularly susceptible to the toxic effects of chemicals if the chemicals cross theplacental barrier. Before birth, the fetus is forming the body organs that need to last a lifetime. Thisis the time when chemical injury may lead to the greatest effects. Laboratory animal andepidemiological studies indicate that VOC exposures to the fetus and children may result in adversehealth effects. Some epidemiological studies have found that exposure to PCE and TCE duringpregnancy increased the risk of the fetus developing central nervous system defects, neural tubedefects, and oral cleft defects. However, other studies have not shown an association between PCEand TCE exposure and birth defects. A childhood cancer study identified a statistically significantincrease of childhood leukemia cases and associated the increase to fetal exposure because themothers drank PCE and TCE contaminated water (12). The study did not find any associationbetween the development of childhood leukemia and the children drinking contaminated water. Theconclusions were based upon imprecise estimates of leukemia risk because of the small number ofsubjects in the study group. The time of exposure was not clearly evident which may not accurately predict the amount or strength of any effect that TCE and PCE may have on the fetus.

B. Health Outcome Data Evaluation

Information provided by the West Virginia Cancer Registry indicates that the 1993-1997 ageadjusted incidence rate (per 100,000) of all sites of cancer in Wood County residents (87,029) for males is 495.6 and 371.9 for females. The age adjusted incidence rate of all sites of cancer in WestVirginia residents, population (1,815,787) for males is 445.1 and 337.0 for females. The total ageadjusted cancer incidence rate for a five year period for all cancer types in all sexes reported inWood County is 418.2 as compared to the total age adjusted incidence rate for a five year period forall cancer types in all sexes of 378.8 for the state of West Virginia. The cancer rate observed in Wood County is not statistically different from the cancer rate observed state wide.

C. Community Health Concerns

During the public availability meeting on March 29, 2000, the following health concerns wereposed:
*Are the high rates of Crohn's Disease in Vienna attributable to exposure from Tetrachloroethene (PCE) and Trichloroethylene (TCE)?
Response: Crohn's Disease is a incurable illness that causes inflamation of the small and large intestines. Families frequently share a similar pattern of the disease. The cause is unknown and there is no current cure for the disease (5). No available data has shown a link between Crohn's disease and PCE and TCE.
*Are PCE and TCE contributing factors to the of liver, heart disease, respiratory illness, and neurological problems in Vienna?
Response: ATSDR has determined that the citizens of Vienna may have been exposed to PCE and TCE for no more than one year. The amount of PCE and TCE detected in the Vienna drinking water system is below levels that have caused liver, heart, neurological, and respiratory illnesses (12). Therefore, it is unlikely that PCE and TCE are contributing factors to any liver, heart, neurological, or respiratory illnesses in Vienna.
*Are PCE and TCE a contributing factor to the cancer in Vienna?
Response: Although PCE and TCE have been identified by the EPA as chemicals that may cause cancer, it is doubtful that adults would get cancer because they drank PCE and TCE contaminated drinking water. The amount of PCE and TCE in the Vienna drinking water system was too low and the length of time (one year or less) was not long enough for cancer to develop in adults. Some studies of people indicate that children may develop leukemia if their mother drank PCE or TCE contaminated drinking water during pregnancy. However, other studies indicated that there is not a risk to children.
*Is the current water supply for Vienna safe to drink?
Response: Yes, the current water being supplied to the city of Vienna is safe for consumption. The annual chemical analysis of the city water indicates that the drinking water meets the water quality standard.
*How often is the water system being checked for contamination?
Response: The public water supply for the city of Vienna is sampled once every month.
*Is the community at risk of future exposure?
Response: If the remediation of the Vienna site is not completed, there is a possibility of the city's water supply wells becoming contaminated again.
*Is it safe to grow a vegetable garden above the contaminated ground water table?
Response: Yes, it is safe to grow gardens in the area. PCE and TCE are volatile organic chemicals which disperse into the air. This prevents concentrations from building up in plant life.
How is the site going to be cleaned up?
Response: The Environmental Protection Agency (EPA) plans to remediate the contaminated ground water plume by using a vacuum vaporization process to remove PCE and TCE from the ground water plume.


CONCLUSIONS

Based upon data reviewed and observations made, the Vienna Tetrachloroethene Superfund Site is currently categorized by the Agency for Toxic Substances and Disease Registry (ATSDR) as a Public Health Hazard. Evaluations of relevant environmental and toxicologic data indicate that exposure to PCE and TCE on-site and off-site in the past has occurred, and future exposures could occur. Some studies indicate that exposure to PCE and TCE in drinking water may increase the chance of developing adverse health effects. Children exposed to PCE as fetuses may have an increased chance of being born and diagnosed with birth defects (i.e., central nervous system defects, neural tube defects, and oral cleft defects).


RECOMMENDATIONS

The interpretation, advice, and recommendations presented are based on the data and informationreferenced. Additional data could alter the recommendations. The conclusions andrecommendations are situation specific and should not be considered applicable to any othersituations. As additional data becomes available, ATSDR will review the data and will respond to additional requests to evaluate public health issues at the site.

  1. The property surrounding the Vienna cleaners should be secured with a fence and notrespassing signs posted on the property until the remediation process is completed.

  2. If any private wells are found within the one mile radius of the site, they should be tested for PCE and TCE contamination, and the owners should be advised not to use the water for consumption.

  3. Efforts for continued characterization and remediation of the ground water plume should be continued, and regular monitoring should be continued.

ATSDR CHILD HEALTH INITIATIVE

ATSDR's Child Health Initiative recognizes that the unique vulnerabilities of infants and childrendemand special emphasis in communities faced with contamination of their water, soil, air, or food. Children are at greater risk than adults from certain kinds of exposures to hazardous substancesemitted from waste sites and emergency events. They are more likely to be exposed because theyplay outdoors and they often bring food into contaminated areas. They are more likely to come intocontact with dust, soil, and heavy vapors close to the ground. Also, they receive higher doses ofchemical exposure due to lower body weights. The developing body systems of children can sustainpermanent damage if toxic exposures occur during critical growth stages.

Some studies have indicated that exposure to PCE and TCE in drinking water may increase thechance of developing adverse health effects. Children exposed to PCE as fetuses may have anincreased chance of being born and diagnosed with birth defects (i.e., central nervous system defects, neural tube defects, and oral cleft defects).


PUBLIC COMMENT PERIOD

The Public Health Assessment (PHA) for the Vienna Tetrachloroethene site was made available forpublic review and comment on November 24, 2000, at the repository in the Vienna Public Library in Vienna, West Virginia. The release of the PHA was announced in the Parkersburg and Sentinel News papers. Television station WTAP and Impact Radio station of Vienna, West Virginia also announced the release of the PHA. ATSDR did not receive any comments.


PUBLIC HEALTH ACTION PLAN

The purpose of the Public Health Action Plan (PHAP) is to ensure that this public health assessment goes beyond presenting ATSDR's conclusions and recommendations about public health issues at theVienna Tetrachloroethene Superfund Site. The PHAP describes actions that are designed to stop orprevent harmful effects resulting from exposure to hazardous substances at the site.

Completed Public Health Actions

  1. The ATSDR team made a site visit to the Vienna Tetrachloroethene Superfund Site on March 29, 2000, to make a visual inspection of the site.

  2. The ATSDR team conducted a public availability meeting and interviewed residents on March 29, 2000.

  3. ATSDR provided the public an opportunity to comment on a draft of this public healthassessment. The public comment period was from November 24, 2000, through January 22,2001. No comments were received.

Planned Public Health Actions

  1. ATSDR's current plan is for the Division of Health Assessment and Consultation, to review EPA's future activity at the site to ensure that clean-up activity is timely and protective of public health.

  2. The Environmental Protection Agency has plans to further characterize and remediate the contaminated ground water plume during the Remedial Investigation phase of the cleanup.

SITE TEAM /AUTHORS

Wayne Hall, MPH
Environmental Health Scientist
Superfund Site Assessment Branch
Division of Health Assessment and Consultation

Shan-Ching Tsai, Ph.D
Toxicologist
Superfund Site Assessment Branch
Division of Health Assessment and Consultation

Lafreta Dalton
Community Involvement Specialist
Community Involvement Activity
Division of Health Assessment and Consultation

Lora Siegmann Werner, MPH
Environmental Health Scientist
Regional Representative ATSDR


REFERENCES

  1. U.S. Environmental Protection Agency, National Priorities List (NPL), ViennaTetrachloroethene, April 1999.

  2. Weston Managers, Preliminary Report on Vienna Wellfield Site. Work assignment #2-251 Vienna PCE Site. December 23, 1997.

  3. U.S. Environmental Protection Agency, Hazard Ranking Score Documentation Record,Vienna Tetrachloroethene Site, December 2, 1998.

  4. GIS Vienna Tetrachloroethene Intro Map. Demographics Statistics Source, 1990 U.S.Census.

  5. Chron's & Colitis Foundation of America (CCFA). April 2000.

  6. Agency for Toxic Substances and Disease Registry. Toxicological Profile forTetrachloroethylene, Public Health Services, U.S. Department of Health & Human Services, Atlanta, GA.. September 1997.

  7. Agency for Toxic Substances and Disease Registry. Toxicological Profile for Trichloroethene, Public Health Services, U.S. Department of Health & Human Services, Atlanta, GA.. September 1997.

  8. Trip report for site visit to Vienna, West Virginia. April 2000.

  9. ATSDR, Public Health Assessment Guidance Manual. Atlanta, Georgia: U.S. Department ofHealth and Human Services, Public Health Service. March 1992. Can be accessad athttp://www.atsdr.cdc.gov/HAC/HAGM.

  10. Bogen, KT; Colston, BW Jr.; Machicao, LK. 1992. Dermal absorption of dilute aqueouschloroform, trichloroethylene, and tetrachloroethylene in hairless guinea pigs. Fundm Appl Toxicol 18:30-39 (As cited in the toxicological profile for PCE)

  11. NTP. 1998. The 8th Report on Carcinogens, 1998 Summary. U.S. Department of Health and Human Services, Public Health Service, National Toxicological Program, 1998.

  12. Massachusetts Department of Public Health. Woburn childhood leukemia follow-up study. Boston: Bureau of Environmental Health Assessment, Massachusetts Department of Public Health, July 1997.

APPENDICES

APPENDIX A: HEALTH COMPARISON VALUES

Health Comparison Value (CVs) are contaminated concentrations found in specific media (air, soil,or water) and used to select contaminants for further evaluation. The CVs used in this documentarelisted below.

Cancer Risk Evaluation Guidelines (CREGs) are estimated contaminant concentrations that wouldbe expected to cause no more than one excess cancer in a million persons exposed over a lifetime. CREGS are calculated from EPA's cancer slop factors (CSF).

Environmental Media Evaluation Guide (EMEGs) are estimated contaminant concentrations inmedia where there is no chance for non-carcinogenic health effects to occur. The EMEG is derivedfrom U.S. AgencyToxic Substances and Disease Registry's (ATSDR) minimal risk level (MRI).

EPA Soil Screening Levels (EPA SSL) are estimated contaminant concentrations in soil whereadditional evaluation is needed to determine if action to eliminate or reduce exposure.

Minimal risk level (MRL) an estimate of daily exposure of a human being to a chemical ( inmg/kg/day) that is likely to be without an appreciable risk of deleterious effects ( noncarcenogenic) over a specified duration of exposure.


APPENDIX B: SITE MAPS

Site Location Map
Figure 1. Site Location Map

Population Map
Figure 2. Population Map


APPENDIX C: LIST OF TABLES

Table 1.

Volatile Organic Chemicals, detected in On-site Soil Gas Monitoring 1993, Above the Comparison Value for the Vienna Cleaners, Tetrachloroethene Site
Contaminant Maximum concentration in Soil Gas (ug/m3) Comparision Values (ug/m3) Comparision Value Source Cancer Class
Tetrachloroethene 28,000 40/2 EMEG/CREG 2A
Trichloroethene 710 100/0.6(0.1) EMEG/CREG 3


Table 2. Volatile Organic Chemicals detected in Off-site Surface Soil and in On-site Subsurface Soil in1997, Above the Comparison Value for the Vienna Tetrachloroethene Site.

Table 1.

Human Health Effects at Various Hydrogen Sulfide Concentrations in Air
Contaminant Maximum Concentration in Surface Soil (mg/kg) Off-Site Maximum Concentration in Subsurface Soil (mg/kg) On-Site Comparison Values (mg/kg) Comparison Value Source Cancer Class
Tetrachloroethene 20 190 20 RMEG 2A
Trichloroethene N/D .47 58 EPA SSL 2A


Table 3.

Volatile Organic Chemicals detected in Off-site Ground Water and Drinking Water Well in1997, Above the Comparison Value for the Vienna Tetrachloroethene Site.
Contaminant Maximum Concentration in Ground Water (ug/L) Off-Site Maximum Concentration in Drinking Water Well (ug/L) Off-Site Comparison Values (ug/L) Comparison Value Source Cancer Class
Tetrachloroethene 34,000 390 100/5 RMEG/MCL 2A
Trichloroethene 6.5N/D5MCL2A

List of Acronyms Appearing in Tables

CREG- Cancer Risk Evaluation Guide for 1x10-6 excess cancer risk
MCL- Maximun Risk Level
RFD- Reference Dose
PPM- Parts Per Million
SSL- Soil Screening Level


APPENDIX D: ENVIRONMENTAL EXPOSURE PATHWAYS

Table 1.

EXPOSURE AND DEMOGRAPHIC STRUCTURE FILE - Completed Exposure Pathway Table - ON-SITE
Pathway Name: Source Medium Exposure Point Exposure Route Receptor Population Time of Exposure Exposure Activities Estimate Number Exposed Chemicals
On-Site Air Vienna CleanersSoil Gas Operation Area Inhalation On-Site WorkersPast Inhalation of soil gas on site20*PCE & TCE
On-Site Soil Vienna CleanersSoil lessthan 6 "belowsurface Operation Area Dermal contact,
Ingestion
On-Site WorkersPast Skin contact with soil, Ingestion and breathing of soil particles 20*PCE & TCE
* The approximate number of exposed individuals is the number of people who worked at Vienna cleaners.


Table 2.

EXPOSURE AND DEMOGRAPHIC STRUCTURE FILE - Completed and Potential Exposure Pathway Table - OFF-SITE
Pathway Name: Source Medium Exposure Point Exposure Route Receptor Population Time of Exposure Exposure Activities Estimate Number Exposed Chemicals
Off-Site Drinking Water ViennaPublicSupplyGroundWater Resident Area Ingestion
Dermal Contact
Residents ofVienna Past,
Future
Ingestion,Inhalation,Dermal14,500*PCE & TCE
Off-Site SoilViennaTCESite SoilMoreThan 6"Below SurfaceResident Area Ingestion
Dermal Inhalation Contact
UtilityworkersGardeners Past,Present,Future Ingestion,Inhalation,Dermalabsorption 14,500*PCE & TCE
* The approximate number of exposed individuals is the number of people who rely upon the city's drinking water supply system.


ATSDR Plain Language Glossary of Environmental Health Terms
Revised -15Dec99

Absorption:
How a chemical enters a person's blood after the chemical has been swallowed, has come into contact with the skin, or has been breathed in.


Acute Exposure:
Contact with a chemical that happens once or only for a limited period of time. ATSDR defines acute exposures as those that might last up to 14 days.


Additive Effect:
A response to a chemical mixture, or combination of substances, that might be expected if the known effects of individual chemicals, seen at specific doses, were added together.


Adverse Health Effect:
A change in body function or the structures of cells that can lead to disease or health problems.


Antagonistic Effect:
A response to a mixture of chemicals or combination of substances that is less than might be expected if the known effects of individual chemicals, seen at specific doses, were added together.


ATSDR:
The Agency for Toxic Substances and Disease Registry. ATSDR is a federal health agency in Atlanta, Georgia that deals with hazardous substance and waste site issues. ATSDR gives people information about harmful chemicals in their environment and tells people how to protect themselves from coming into contact with chemicals.


Background Level:
An average or expected amount of a chemical in a specific environment. Or, amounts of chemicals that occur naturally in a specific environment.


Biota:
Used in public health, things that humans would eat - including animals, fish and plants.


CAP:
See Community Assistance Panel.


Cancer:
A group of diseases which occur when cells in the body become abnormal and grow, or multiply, out of control


Carcinogen:
Any substance shown to cause tumors or cancer in experimental studies.


CERCLA:
See Comprehensive Environmental Response, Compensation, and Liability Act.


Chronic Exposure:
A contact with a substance or chemical that happens over a long period of time. ATSDR considers exposures of more than one year to be chronic.


Completed Exposure Pathway:
See Exposure Pathway.


Community Assistance Panel (CAP):
A group of people from the community and health and environmental agencies who work together on issues and problems at hazardous waste sites.


Comparison Value (CVs):
Concentrations or the amount of substances in air, water, food, and soil that are unlikely, upon exposure, to cause adverse health effects. Comparison values are used by health assessors to select which substances and environmental media (air, water, food and soil) need additional evaluation while health concerns or effects are investigated.


Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA):
CERCLA was put into place in 1980. It is also known as Superfund. This act concerns releases of hazardous substances into the environment, and the cleanup of these substances and hazardous waste sites. ATSDR was created by this act and is responsible for looking into the health issues related to hazardous waste sites.


Concern:
A belief or worry that chemicals in the environment might cause harm to people.


Concentration:
How much or the amount of a substance present in a certain amount of soil, water, air, or food.


Contaminant:
See Environmental Contaminant.


Delayed Health Effect:
A disease or injury that happens as a result of exposures that may have occurred far in the past.


Dermal Contact:
A chemical getting onto your skin. (see Route of Exposure).


Dose:
The amount of a substance to which a person may be exposed, usually on a daily basis. Dose is often explained as "amount of substance(s) per body weight per day".


Dose / Response:
The relationship between the amount of exposure (dose) and the change in body function or health that result.


Duration:
The amount of time (days, months, years) that a person is exposed to a chemical.


Environmental Contaminant:
A substance (chemical) that gets into a system (person, animal, or the environment) in amounts higher than that found in Background Level, or what would be expected.


Environmental Media:
Usually refers to the air, water, and soil in which chemical of interest are found. Sometimes refers to the plants and animals that are eaten by humans. Environmental Media is the second part of an Exposure Pathway.


U.S. Environmental Protection Agency (EPA):
The federal agency that develops and enforces environmental laws to protect the environment and the public's health.


Epidemiology:
The study of the different factors that determine how often, in how many people, and in which people will disease occur.


Exposure:
Coming into contact with a chemical substance.(For the three ways people can come in contact with substances, see Route of Exposure.)


Exposure Assessment:
The process of finding the ways people come in contact with chemicals, how often and how long they come in contact with chemicals, and the amounts of chemicals with which they come in contact.


Exposure Pathway:
A description of the way that a chemical moves from its source (where it began) to where and how people can come into contact with (or get exposed to) the chemical.

ATSDR defines an exposure pathway as having 5 parts:
  • Source of Contamination,

  • Environmental Media and Transport Mechanism,

  • Point of Exposure,

  • Route of Exposure; and,

  • Receptor Population.

When all 5 parts of an exposure pathway are present, it is called a Completed Exposure Pathway. Each of these 5 terms is defined in this Glossary.


Frequency:
How often a person is exposed to a chemical over time; for example, every day, once a week, twice a month.


Hazardous Waste:
Substances that have been released or thrown away into the environment and, under certain conditions, could be harmful to people who come into contact with them.


Health Effect:
ATSDR deals only with Adverse Health Effects (see definition in this Glossary).


Indeterminate Public Health Hazard:
The category is used in Public Health Assessment documents for sites where important information is lacking (missing or has not yet been gathered) about site-related chemical exposures.


Ingestion:
Swallowing something, as in eating or drinking. It is a way a chemical can enter your body (See Route of Exposure).


Inhalation:
Breathing. It is a way a chemical can enter your body (See Route of Exposure).


LOAEL:
Lowest Observed Adverse Effect Level. The lowest dose of a chemical in a study, or group of studies, that has caused harmful health effects in people or animals.


Malignancy:
See Cancer.


MRL:
Minimal Risk Level. An estimate of daily human exposure - by a specified route and length of time -- to a dose of chemical that is likely to be without a measurable risk of adverse, noncancerous effects. An MRL should not be used as a predictor of adverse health effects.


NPL:
The National Priorities List. (Which is part of Superfund.) A list kept by the U.S. Environmental Protection Agency (EPA) of the most serious, uncontrolled or abandoned hazardous waste sites in the country. An NPL site needs to be cleaned up or is being looked at to see if people can be exposed to chemicals from the site.


NOAEL:
No Observed Adverse Effect Level. The highest dose of a chemical in a study, or group of studies, that did not cause harmful health effects in people or animals.


No Apparent Public Health Hazard:
The category is used in ATSDR's Public Health Assessment documents for sites where exposure to site-related chemicals may have occurred in the past or is still occurring but the exposures are not at levels expected to cause adverse health effects.


No Public Health Hazard:
The category is used in ATSDR's Public Health Assessment documents for sites where there is evidence of an absence of exposure to site-related chemicals.


PHA:
Public Health Assessment. A report or document that looks at chemicals at a hazardous waste site and tells if people could be harmed from coming into contact with those chemicals. The PHA also tells if possible further public health actions are needed.


Plume:
A line or column of air or water containing chemicals moving from the source to areas further away. A plume can be a column or clouds of smoke from a chimney or contaminated underground water sources or contaminated surface water (such as lakes, ponds and streams).


Point of Exposure:
The place where someone can come into contact with a contaminated environmental medium (air, water, food or soil). For examples:
the area of a playground that has contaminated dirt, a contaminated spring used for drinking water, the location where fruits or vegetables are grown in contaminated soil, or the backyard area where someone might breathe contaminated air.


Population:
A group of people living in a certain area; or the number of people in a certain area.


PRP:
Potentially Responsible Party. A company, government or person that is responsible for causing the pollution at a hazardous waste site. PRP's are expected to help pay for the clean up of a site.


Public Health Assessment(s):
See PHA.


Public Health Hazard:
The category is used in PHAs for sites that have certain physical features or evidence of chronic, site-related chemical exposure that could result in adverse health effects.


Public Health Hazard Criteria:
PHA categories given to a site which tell whether people could be harmed by conditions present at the site. Each are defined in the Glossary. The categories are:
  • Urgent Public Health Hazard

  • Public Health Hazard

  • Indeterminate Public Health Hazard

  • No Apparent Public Health Hazard

  • No Public Health Hazard

Receptor Population:
People who live or work in the path of one or more chemicals, and who could come into contact with them (See Exposure Pathway).


Reference Dose (RfD):
An estimate, with safety factors (see safety factor) built in, of the daily, life-time exposure of human populations to a possible hazard that is not likely to cause harm to the person.


Route of Exposure:
The way a chemical can get into a person's body. There are three exposure routes:
- breathing (also called inhalation),
- eating or drinking (also called ingestion), and
- or getting something on the skin (also called dermal contact).


Safety Factor:
Also called Uncertainty Factor. When scientists don't have enough information to decide if an exposure will cause harm to people, they use "safety factors" and formulas in place of the information that is not known. These factors and formulas can help determine the amount of a chemical that is not likely to cause harm to people.


SARA:
The Superfund Amendments and Reauthorization Act in 1986 amended CERCLA and expanded the health-related responsibilities of ATSDR. CERCLA and SARA direct ATSDR to look into the health effects from chemical exposures at hazardous waste sites.


Sample Size:
The number of people that are needed for a health study.


Sample:
A small number of people chosen from a larger population (See Population).


Source (of Contamination):
The place where a chemical comes from, such as a landfill, pond, creek, incinerator, tank, or drum. Contaminant source is the first part of an Exposure Pathway.


Special Populations:
People who may be more sensitive to chemical exposures because of certain factors such as age, a disease they already have, occupation, sex, or certain behaviors (like cigarette smoking). Children, pregnant women, and older people are often considered special populations.


Statistics:
A branch of the math process of collecting, looking at, and summarizing data or information.


Superfund Site:
See NPL.


Survey:
A way to collect information or data from a group of people (population). Surveys can be done by phone, mail, or in person. ATSDR cannot do surveys of more than nine people without approval from the U.S. Department of Health and Human Services.


Synergistic effect:
A health effect from an exposure to more than one chemical, where one of the chemicals worsens the effect of another chemical. The combined effect of the chemicals acting together are greater than the effects of the chemicals acting by themselves.


Toxic:
Harmful. Any substance or chemical can be toxic at a certain dose (amount). The dose is what determines the potential harm of a chemical and whether it would cause someone to get sick.


Toxicology:
The study of the harmful effects of chemicals on humans or animals.


Tumor:
Abnormal growth of tissue or cells that have formed a lump or mass.


Uncertainty Factor:
See Safety Factor.


Urgent Public Health Hazard:
This category is used in ATSDR's Public Health Assessment documents for sites that have certain physical features or evidence of short-term (less than 1 year), site-related chemical exposure that could result in adverse health effects and require quick intervention to stop people from being exposed.


Table of Contents

  
 
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