PETITIONED PUBLIC HEALTH ASSESSMENT
GSX LANDFILL
PINEWOOD, SUMTER COUNTY, SOUTH CAROLINA
ENVIRONMENTAL CONTAMINATION AND OTHER HAZARDS
1. Groundwater Contamination
Groundwater in the uppermost aquifer (Sawdust Landing) of the GSX site has been contaminated with VOCs and heavy metals (21,22). Chromium was detected in on-site groundwater above the EPA Maximum Contaminant Level (MCL) in November 1983 (1). A change in groundwater quality for some on-site monitoring wells was reported to SCDHEC in May 1984 (1). VOCs were detected in on-site groundwater in June 1986 and November 1986 (23). GSX conducted a groundwater assessment to define the extent of groundwater contamination in 1990 (21,22). Maximum concentrations of contaminants detected in groundwater during the 1990 groundwater assessment are shown in Appendix C. The extent of the groundwater contamination plume is also shown in Appendix C. GSX attributed the groundwater contamination to opaline claystone mining and waste disposal activities conducted by previous owners, rather than to releases from lined hazardous waste landfill cells. Corrective action to extract and treat contaminated groundwater beneath the site has been conducted since June 1987 (21).
In accordance with its operating permits, Laidlaw conducts quarterly sampling of more than 100 monitoring wells downgradient of the waste cells. In addition, groundwater flow direction is measured monthly. This sampling data and groundwater flow information is reviewed by EPA and the SCDHEC. As of 1997, regulators report no evidence of groundwater contamination from current landfill and waste disposal activities and that existing contamination is being contained (i.e., contamination is not migrating beyond a limited area on site) (135).
2. Surface Water Contamination
During the groundwater assessment conducted in 1990, GSX analyzed samples collected from man-made surface water streams that were constructed to control surface water runoff on site (21). Results of those analyses indicate that these on-site streams were contaminated with VOCs. Contamination of surface water was attributed to past mining operations and waste disposal activities conducted by previous owners of the property. Maximum concentrations of contaminants detected in the streams are shown in Appendix C. The streams discharge into two on-site sedimentation ponds, which are monitored monthly. The sedimentation ponds discharge into Lake Marion. Contaminants have not been detected in the sedimentation ponds (24). Locations of on-site surface water sampling points are shown in Appendix C.
As required by its operating permits, Laidlaw performs quarterly sampling of on-site surface water and submits the sampling data to EPA and the SCDHEC. As of 1997, regulators report no evidence of more recent contamination of surface water.
3. Air Contamination
Several studies of on-site air quality have been conducted by GSX and by SCDHEC (25-28). The dates of these studies are included in the Site History in Appendix B. VOCs such as xylenes and methylene chloride have been detected in air on site. In addition, respirable dust above U.S. Occupational Safety and Health Administration (OSHA) Permissible Exposure Limits (PELs) has been detected at several locations on site. Locations of air sampling points are shown in Appendix C.
The rotary kiln, which operated until 1990 at the on-site opaline claystone drying plant, was permitted by SCDHEC to burn waste oil as fuel. SCDHEC permitted GSX to discharge up to 4,000 parts per million halogens into the air. Compound-specific monitoring of stack emissions from the rotary kiln was not conducted. Because the kiln reportedly burned oil at fairly low temperatures, organic compounds may not have been destroyed in the kiln (1). Concentrations of organic compounds that may have been emitted to the atmosphere as a result of these activities are not known.
In 1997, air modeling commissioned by Laidlaw and approved by SCDHEC has determined that the facility meets South Carolina Maximum Acceptable Air Concentrations at both the fenceline and the property boundary. The facility's current operating permit requires that a detailed air monitoring plan be developed and implemented. Air monitoring will commence after the plan is approved by SCDHEC and will serve to verify air modeling results.
1. Groundwater Contamination
SCDHEC analyzed samples collected from several domestic drinking water wells adjacent to the GSX Landfill in 1986 and in 1987 (22,30). No contaminants known to be related to the GSX site were detected. Coliform bacteria at concentrations exceeding SCDHEC water quality standards were detected in two residential water wells, and 4-methyl-3-pentanoic acid was also detected in one of the residential water wells contaminated by bacteria. The concentration of this organic compound was not reported by the SCDHEC laboratory. One of the contaminated water wells was in a fenced area containing various livestock. The SCDHEC representative described conditions around the other contaminated residential water well as "not very good," with no further elaboration. The SCDHEC representative noted that some residential water wells did not have sufficient grout around the surface casing to prevent infiltration of contaminants from ground surface into the well annuli. The presence of coliform bacteria, coupled with the fact that the domestic water wells are hydraulically upgradient from the GSX landfill, and the fact that they are poorly constructed and poorly sited, indicates that contaminants detected in these wells are not related to waste disposal activities at the site. Locations of residential water wells analyzed by SCDHEC are shown in Appendix C.
2. Surface Water Quality
Surface water from the GSX Landfill discharges into Lake Marion from the two on-site sedimentation ponds. Water, fish tissue, and sediment samples have been collected from Lake Marion by SCDHEC and by EPA on several occasions (June 1986, July 1986, July 1987, and November 1987) (31-36). Locations of surface water sampling points are shown in Appendix C. No contamination of off-site surface water, sediment, or fish tissue could be attributed to the GSX landfill.
A massive fish kill occurred in Lake Marion in the general vicinity of the GSX Landfill in August 1986 (37). SCDHEC aquatic biologists attributed the fish kill to natural causes (lack of dissolved oxygen in the water, a fairly common occurrence in slow-moving water bodies).
3. Air Quality
No off-site air monitoring had been conducted at the time of this public health assessment. Development and implementation of an air monitoring plan is required as a condition of the facility's operating permit. In 1994, the facility developed an Ambient Air Monitoring Plan, which is currently (summer 1997) being reviewed by the SCDHEC.
4. Releases from Waste Transportation Practices
Wastes are transported to the GSX Landfill via trucks and rail cars. Several incidents have been recorded in which trucks and rail cars have released waste en route to the facility as a result of accidents or as a result of leakage out of the waste containment areas of the vehicles. In October 1982, a truck arrived at the landfill with waste "oozing out of the tailgate," according to a SCDHEC inspector (38). Bulk waste was spilled in transit at the junction of State Routes 378 and 261 in October 1982. In February 1985, a rail car carrying waste rolled off the track 2 miles from the GSX site (39). In May 1985, a truckload of waste being carried into the facility ignited, resulting in the evacuation of the landfill (40). The wastes consisted of incinerator ash and oily rags. A similar incident occurred the following month, in June 1985, when a truck carrying baghouse dust and rags contaminated with lead and mercury arrived at the facility with the waste load smoldering (41). A SCDHEC inspector reported that a truck arrived at the facility in August 1985 with leaking wastes containing treated hexavalent chromium, and that the wastes leaked for 3 days into a holding pool (42). In December 1986, waste leakage was detected in 12 of 18 rail cars carrying soil contaminated with sodium dichromate into the facility (43).
Environmental monitoring was not conducted at the time of these releases to determine the impact of the releases on the environment and on public health. However, spills were remediated in accordance with SCDHEC regulations, and no outstanding cleanup issues were related to these releases.
C. Quality Assurance and Quality Control
Quality assurance and quality control (QA/QC) programs assure the reliability and accuracy of monitoring and measurement data. In preparing this public health assessment, ATSDR relied on information provided in the reference documents and assumes that adequate quality control measures were followed with regard to chain-of-custody, laboratory procedures, and data reporting. Validity of the analysis and conclusions drawn for this public health assessment is determined by the availability and reliability of referenced information.
When descriptions were provided, QA/QC measures appeared consistent with measures normally taken with environmental sampling and analysis. Detailed sample collection and preservation procedures, as well as laboratory QA/QC data for analyses, were included in SCDHEC air sampling report for samples collected from June to September 1985. Sample collection and preservation procedures were described in reports of SCDHEC analyses of tissue taken from Lake Marion fish 1986. These analyses were conducted according to SCDHEC QA/QC procedures for analyses of fish tissue. Analyses results of trip blanks, surrogate recovery results, and acceptable limits were included in reports of air samples analyzed by GSX in November 1986.
In some cases, a description of QA/QC measures was not provided. No QA/QC data were included in an air sampling report prepared for the landfill operators by a consultant in 1980. QA/QC information was not available in the information reviewed by ATSDR for SCDHEC samples collected at residential water wells in 1986. In addition, SCDHEC did not report the concentration of 4-methyl-3-pentanoic acid detected in one residential water well. QA/QC data were not included in the 1990 groundwater assessment report prepared by consultants for GSX.
The GSX site, which continues to operate as a waste disposal facility, requires the use of heavy equipment. On-site earth-moving equipment and on-site soil excavations may pose physical hazards to site trespassers, especially to small children. Because access to the site is restricted, the likelihood of human contact with on-site physical hazards is reduced.
Before the ATSDR site visit, residents presented concerns to ATSDR representatives regarding the speed and volume of trucks carrying hazardous waste to the GSX Landfill. The reason for these concerns was confirmed by ATSDR during the site visit in May 1990. ATSDR representatives traveled in a vehicle to the GSX Landfill over small, two-lane roads. The vehicle carrying ATSDR representatives was traveling at the speed limit, but several dump trucks with beds covered by tarpaulins overtook and passed the ATSDR vehicle. One of these trucks was observed turning into the GSX Landfill. Observations during the site visit indicated that trucks hauling waste to the facility present a physical hazard to other motorists when the trucks are traveling in excess of the speed limit. Waste transporters traveling at high speeds on narrow roads present a physical hazard to other motorists traveling on those roads.
An environmental exposure pathway consists of a source of contamination; an environmental medium in which the contaminants may be present or may migrate; points of human exposure; routes of human exposure such as inhalation, ingestion, or dermal absorption; and a receptor population. The potential for contaminants to represent public health hazards via environmental exposure pathways in the past, present, and future are discussed in the following section. Environmental exposure pathway components are shown in Appendix C in relation to contaminants detected in the environment in and around the GSX Landfill.
1. Transportation Sources
Because releases from transporters have been documented several times, transporters of hazardous wastes to the GSX Landfill may be considered either potential or actual sources of contamination from the points of origin to the GSX Landfill. Rail cars pass over Lake Marion en route to the landfill, and leaking rail cars may have discharged wastes into the lake. Trucks leaking wastes, or trucks whose cargos of waste are blowing in the wind or burning, are sources of contamination. Trucks that are involved in accidents are also sources of contamination. Transporters have been sources of contamination in the past and are potential sources of contamination in the future.
2. On-site Sources
Mining of opaline claystone presents a past and current source of air contaminants in the form of respirable dust and crystalline silica. The former waste oil holding pits were past potential sources of contamination via volatilization of organic compounds into the air and potential migration of contaminants to the groundwater.
Waste handling operations are past, current, and future sources of air contaminants. VOCs have been detected on site, and readings for respirable dusts have exceeded OSHA PELs. The potential for air contamination is higher during material handling activities. A recently constructed building enclosing the waste treatment area now limits fugitive dust.
The landfill is a potential source of groundwater contamination if leachate escapes the landfill and leaks into the surrounding soil and groundwater, or if the water table saturates the landfill and causes migration of contaminated groundwater. Laidlaw currently reduces the toxicity of wastes by pretreating them before burying them in the waste cells. Landfill liners, consisting of several layers of natural and synthetic materials, are in place to contain leachate from the waste cells, and Laidlaw's groundwater monitoring system should detect leaks in time to prevent contamination from migrating off site. The waste cells also incorporate a leachate collection system that minimizes the amount of free liquid seeping onto the liner. In addition, a french drain system, installed along the northern and eastern boundaries of the landfill, lowers the natural water table and prevents groundwater from infiltrating the waste cells. The liners, leachate collection systems, and french drain are currently very effective in containing contaminants within the waste cells and reducing the water table below the buried waste. However, some wastes in the cells will remain toxic over a very long period of time. During that period, the condition of the waste cell components, the local geology, or the behavior of the groundwater could change and cause a release of contaminants into the environment. Although none of these conditions is expected to change in the future, the sound condition of the landfill can be verified only with a long-term monitoring program. The landfill's operating permits require quarterly sampling of the monitoring wells surrounding each waste cell; these sample results are reviewed by EPA and the SCDHEC to ensure that any release of contaminants from the landfill will be identified and cleaned up before it can harm the environment or affect public health (135). The permit requires Laidlaw to conduct groundwater monitoring for a period of 100 years following closure of the facility (assuming no contamination is detected during that 100-year period).
Other potential sources of contamination on the GSX Landfill include the drum-storage areas, drum-treating areas, overnight truck-parking areas, an on-site drinking water well, and the rail-car waste transfer station. Contaminants could be released during waste handling activities in these areas.
3. Off-site Sources
Off-site sources of contaminants in the Rimini area consist primarily of agricultural fields treated with pesticides (unrelated to the GSX Landfill). The types of pesticides used in the area were mentioned previously in the Demographics, Land Use, and Natural Resource Use section. The agricultural fields are located adjacent to residences along Route 51, and also between Route 51 and the rail-car waste transfer station east of the main GSX facility. Information on the specific types of pesticides applied to the agricultural areas was not available at the time of this assessment. Herbicides and pesticides have also been used to control aquatic weeds and mosquitos in Lake Marion. Livestock feeding and shelter areas adjacent to residential water wells are also off-site sources of bacterial contamination, particularly when residential water wells are poorly constructed.
1. Groundwater Contamination
As of 1997, groundwater monitoring conducted by the facility and SCDHEC indicates that the groundwater contamination plume does not extend beyond the facility property boundary; Laidlaw is containing contamination through active removal and treatment of water from the upper aquifer (21). Off-site groundwater contamination in residential water wells consists primarily of bacterial contamination, reportedly resulting from poorly constructed wells in bad locations.
2. Surface Water Contamination
Surface water monitoring data indicate that contaminants from the GSX landfill have been present in on-site streams in the past. This historical contamination is attributed to mining and waste burning activities conducted previous owners. As of 1997, contaminants have not been detected in on-site ponds that are fed by those streams and discharge into Lake Marion, nor have they been detected in off-site surface water, sediment, or fish tissue taken from Lake Marion.
3. Air Contamination
Past sampling has found on-site air to be contaminated with VOCs and respirable dust. Air monitoring was not conducted during periods when smoldering wastes were transported to the facility, nor did the landfill operators conduct off-site air monitoring or compound-specific air monitoring of stack emissions from burning waste oil in the rotary kiln. Therefore, it is not known whether air contaminants migrated off site during kiln operations. However, air modeling of current landfill operations has been conducted by Laidlaw and reviewed by SCDHEC; this modeling has determined that the landfill meets state requirements for air emissions. An Ambient Air Monitoring Plan developed by Laidlaw for the facility is currently under review by regulators (135).
4. Transportation Releases
Concentrations of contaminants released to the environment as a result of leakage during transportation and as a result of transportation accidents are not known because monitoring was not conducted at the time the releases occurred. However, cleanup actions were performed at these sites in accordance with SCDHEC regulations.
Humans may be exposed to air contaminants on site. It is not known whether human exposure occurred off-site as a result of air emissions from the accidental burning of waste during transportation to the facility, or as a result of burning waste oil in the rotary kiln, or due to other site-related activities. A recently-constructed building enclosing the waste treatment area has reduced the potential for exposure to air contamination from that source. An on-site drinking water well, installed within the past four years, may been used in the past by on-site workers for drinking water purposes; however, available data indicate that the well is not contaminated. At this time, Laidlaw employees drink bottled water on site, the plume of groundwater contamination is being treated for VOCs and has not migrated off site, and there are no indications that landfilling operations are causing groundwater contamination, or that contaminants from the facility are reaching Lake Marion. Limited human exposure to on-site surface water contaminants is possible. It is not known whether people have been exposed to releases of hazardous wastes during waste transportation activities.
Humans may be exposed to respirable dust in air primarily via inhalation, and they may be exposed to organic compounds in air via inhalation, ingestion, and dermal absorption or dermal contact. Dermal contact with VOCs in on-site streams is the most likely route of human exposure to surface water contaminants. Dermal contact, dermal absorption of permeable organic compounds, inhalation, and incidental ingestion are potential routes of human exposure to contaminants released during waste transportation activities.
Employees on-site may be exposed to air contaminants, although laborers working close to active waste disposal cells and in drum storage and treatment areas wear protective clothing and equipment to mitigate these exposures. Visitors to the site may receive sporadic, low doses of air contaminants released during routine operations, although the recently-constructed waste treatment building should limit this exposure. ATSDR representatives noted the presence of chemical odors on site during a past site visit.
It is not known whether the surrounding population was exposed to airborne contaminants during releases that occurred while accidentally ignited wastes were transported to the site. It is also not known whether the surrounding community was exposed to airborne organic compounds as a result of burning waste oil (as a fuel) at the rotary kiln.
The population that may have been exposed because of waste transportation releases is not known.
F. Summary of Pathways Analyses
Air: Air contamination presents a potential environmental exposure pathway for employees at the site. However, the use of protective clothing and equipment will mitigate exposure. Because off-site air data are lacking, it is not known whether off-site residents have been exposed to air contaminants. It is also not known whether residents were exposed to contaminants potentially released off site during transportation of wastes, although no evidence exists that such exposures occurred.
Surface Water: On-site exposure to surface water contaminants may have occurred in the past, but off-site exposure to surface water contaminants has not been documented.
Groundwater: Groundwater contamination has not resulted in a completed exposure pathway. Workers are not believed to have been exposed to on-site groundwater contamination because the facility provides the workers with bottled water for drinking water purposes. A potential exposure pathway would exist if contaminated groundwater were to migrate off-site. Contaminated groundwater, however, is being extracted and treated. Regular monitoring reveals that contamination is being contained on-site. Sampling results also indicated that current landfill activities are not contaminating the groundwater. The current liner, leachate collection system, and french drain effectively contain leachate and lower the surrounding water table. However, placement of hazardous wastes below the natural water table presents a long-term potential for contamination and subsequent exposure and requires continued long-term monitoring and evaluation by the facility and regulators. As previously stated, the facility's permit requires Laidlaw to conduct groundwater monitoring for a period of 100 years, assuming no contamination is detected during this time, following the closure of the landfill.
Information on the toxicology of contaminants detected in the vicinity of the site and evaluations of residents' medical information are presented in this section. In addition, the community health concerns presented previously are evaluated in the subsection entitled "Community Health Concern Evaluation".
The pathways analysis did not indicate a complete pathway for any specific compound.
The community would like to know where compounds that were detected in the serum samples taken in 1986 could have originated. This section will focus on those compounds and attempt to determine whether they can be attributed to the site. In addition, this section will address the residents' symptoms and the issue of fish contamination, which were raised as community concerns.
Compounds found in Blood Samples from People in the Community:
Polychlorinated Biphenyls (PCBs)
PCBs were not detected in either the groundwater or the surface water at the landfill. No completed pathway for PCBs exists at the facility. PCBs are commercial compounds that were widely used for insulation and lubrication in electrical cables, transformers, and other equipment. There are 209 individual PCB compounds. Commercial manufacture of PCBs was stopped in the United States in 1977. Their uses were halted because of the persistence of these compounds in the environment and the potential for adverse health effects from exposure to PCBs (44,45).
Commercial formulations consist of a variety of PCBs and impurities. Monsanto was the only domestic producer of PCBs. The trade names consisted of Aroclor followed by a four-digit number. The last two digits of the number indicated the approximate concentrations of chlorine in the mixture. The more highly chlorinated PCB mixtures (Aroclor 1254, Aroclor 1260) have been shown to be carcinogenic in some species of animals. At this time, evidence is inadequate to state that PCBs are carcinogenic in humans. EPA has classified PCBs as probable human carcinogens. The International Agency for Research on Cancer (IARC) has classified PCBs in Group 2B (Group 2B includes those chemicals classified as potential human carcinogens) based on sufficient evidence in animals, inadequate evidence in humans, and inadequate evidence for mutagenicity. The National Institute for Occupational Safety and Health (NIOSH) has recommended that PCBs be regarded as potential human carcinogens in the workplace (44,46).
Studies in animals and workers have indicated that the liver and skin are the major affected organs. Increased serum levels of liver enzymes have been seen in some studies of workers (44,47,48). Other studies have not found a large number of workers with high enzymes (49,50,51). Dermatologic effects such as chloracne, pigmentary changes, rashes, and changes such as swelling or thickening have been described (44,49,50,52,53,54). Chloracne is a chronic skin condition produced by environmental exposures to certain compounds containing chemicals such as chlorine or bromine. Two predominant skin lesions are seen in chloracne cases: the chloracne cyst and the comedo (blackhead). The chloracne cyst is a skin colored sac with a central opening. Most studies in workers indicated that persons with chloracne also have some evidence of liver injury (51,55).
PCBs have been shown to cross the placenta, so that fetuses of women who have been exposed to PCBs will also be exposed. Several reports have indicated slight effects on child development when mothers were occupationally exposed to PCBs during pregnancy or were consumers of PCB-contaminated fish during pregnancy. These effects have included decreases in birth weight, gestational age, and cognitive functioning (44,56,57).
Nursing infants represent a subpopulation especially sensitive to PCB exposure. Breast milk has a high fat content, and PCBs are excreted in the milk. Breast-fed infants have an additional risk caused by a steroid that is excreted in human breast milk that inhibits the infants' ability to excrete PCBs. A study by Gladen et al did not demonstrate any effect on infant psychomotor response associated with exposure through breast feeding (58). Serum samples taken in the community included samples from 14 children. The frequency of breast-feeding among women in the area is not known.
In the United States, the median PCB level in blood of the population without occupational exposure has been found to be less than 10 nanograms per milliliter (ng/mL) (this may also be noted as 10 parts per billion [ppb]). The sex and age of the population under study must be taken into account (59). Mean serum levels were usually 4-8 ng/mL (ppb), and 95% of people tested had levels less than 20 ng/mL (ppb) (44). Fewer studies have used adipose samples in the population. Although variation occurred in the groups studied, PCB levels in adipose tissue are 100-200 times the levels in blood serum (51). Studies attempting to correlate serum and adipose levels with health effects have had inconsistent results (44).
No cross sectional studies have been done of PCB levels in people who have not had unusual exposures (such as through work). (A cross sectional study examines health-related characteristics in a population at a single point in time.) However, several small studies have used unexposed controls. This gives some information on the levels seen in unexposed groups. Although differences in methodology make it difficult to directly compare these studies, they do give an indication of the ranges of PCB levels that have been seen. A summary of some of these studies is found in Appendix C.
The community around the GSX Landfill is concerned about environmental exposures to PCBs from the facility. A few studies of populations living near hazardous waste sites have assessed exposure. These studies have not demonstrated significantly higher PCB levels in sera from populations living around hazardous waste sites than the ranges found in other non-occupationally exposed populations (60). Levels of PCBs in residents around the GSX facility are not higher than those seen in other non-occupational exposed populations.
Pesticides
No known pathway for DDT exists at the facility; it was not found in the groundwater or surface water at the facility.
DDT was first produced in 1944. The peak production in the United States was in 1964 (200,000-250,000 tons). In 1966, DDT, Aldrin, and Toxaphene represented 50%-75% of the world's production of insecticides. In 1969, some states restricted DDT use, and, in 1972, DDT was banned because of concern over its persistence in the environment, the possibility of long-term effects, and the increasing resistance of insects to its effects. DDE, a metabolite of DDT, is the major storage product of DDT in fats. DDE is as toxic to mammals as DDT, but insects are not sensitive to DDE.
DDT has not been shown to cause significant chromosomal aberrations in rabbit or human blood cultures. Worker study comparisons indicate no increase in chromosomal aberrations. Chronic exposure caused increased cancer in mice, rats, and hamsters but not in dogs or nonhuman primates. EPA classifies DDT as a probable carcinogen (61).
DDT exhibits effects similar to those of estrogen (one of the "female" hormones). Chronic doses have shown numerous adverse health effects such as infertility, decreased libido, and increased mortality of offspring in animals (61). No ill effects on health have been demonstrated from long-term, low-dose exposure to DDT in humans (61,62). Single high doses have resulted in headache, nausea, tachycardia (fast heartbeat), and convulsions (62).
No exposure pathway was identified for trans-Nonachlor at this site because it was not detected in samples taken at the site. Trans-Nonachlor is an organochlorine residue from chlordane or heptachlor. It was detected at levels greater than 2 ppb in 6% of serum sampled in the second National Health and Nutrition Examination Survey (NHANES II, 1976-1980). The median serum level observed was 1.7 ppb. The range of levels was 1-17 ppb (63). Levels in adipose tissue were greater than 20 ppb in 97% of samples in the Fiscal Year 1978 survey, National Human Adipose Tissue Monitoring Program (64).
Chlordane does not have an identified completed pathway from the facility at the present time. Chlordane was used as an insecticide in the United States until 1988. In the 1970s, the pattern of use was: termite control - 35%, agricultural crops - 28%, home and garden use - 30%, and turf & ornamental - 7%. In 1978, use of chlordane was restricted to the control of termites and use on non-food crops. In 1983, its use on non-food crops was canceled (65). The literature indicates that chlordane does not break down rapidly in soils and can persist for up to 20 years. No harmful health effects have been observed from studies of workers making or using chlordane. In cases where a person has swallowed large amounts of chlordane, convulsions and death have resulted. Exposure to more moderate levels can cause headaches, confusion, visual problems, nausea, stomach cramping, and diarrhea (65).
No completed pathway from the facility exists for heptachlor epoxide at this time. Heptachlor epoxide is the oxidation product of heptachlor. The production of heptachlor in the United States was stopped in 1987. Previous uses of heptachlor included termite control, dipping of non-food plants, and treatment of utility pedestals for fire ant control. Heptachlor epoxide is more acutely toxic than the parent compound. Heptachlor epoxide is extremely persistent in the environment with a half-life of 14 years. These compounds tend to bioaccumulate in the environment.
No studies have been located that identify the direct effects of exposure to heptachlor epoxide on human health. Animal studies indicate that the liver is the most sensitive target organ. Animals have also demonstrated tremors and convulsions from exposure to heptachlor epoxide (45,66).
Levels of heptachlor epoxide greater than 1-2 ppb in serum were found in 4% of the population; levels greater than 10-20 ppb were found in adipose tissue in 96% of the population (64). Levels in breast milk can be substantial. See Appendix C for further information on the levels of heptachlor epoxide seen in populations that have been described in the literature.
Potential exposures to heptachlor epoxide, other than for infants through breast feeding include: inhalation in areas where termites have been treated, exposure to soils in areas where the chemical was used as a pesticide, waste sites, and foodstuffs (although all studies were conducted before 1980) (67).
Hexachlorobenzene has not been found in on-site surface water or groundwater. No exposure pathway from the facility has been identified. Hexachlorobenzene (HCB, Perchlorobenzene) is not currently commercially manufactured in the United States but is found as a manufacturing by-product or impurity in the production of chlorinated solvents and pesticides. It was used as a pesticide until 1985 and is widely distributed as a contaminant in industrial areas and in agricultural areas producing grain (45). HCB levels have been found in 93% of adipose tissue samples in the United States and 4% of serum samples (64).
Studies on the effects of oral ingestion of HCB come from Turkey, where, in the mid-50s, HCB-contaminated grain was ingested resulting in the occurrence of more than 3,000 cases of acquired toxic porphyria cutanea tarda (PCT) (66). The amount ingested averaged 0.05-2.0 gram/day (68). The symptoms of PCT are chronic skin lesions and liver (hepatic) disease. PCT results from a decrease in hepatic uroporphyrinogen decarboxylase activity (a liver enzyme). This leads to a disturbance in hepatic heme synthesis and skin photosensitivity. Skin symptoms include increased facial pigmentation, increased fragility, erythema (redness), vesicular (blisters), and ulcerative lesions. Skin thickening and increased hair on forehead, cheeks, and forearms are common. Neuropsychiatric attacks (these may include such things as numbness or pain in the arms and legs, paralysis, restlessness, or visual hallucinations) occur in other forms of porphyria, but not in PCT (69). Appendix C indicates values in the literature from previous studies for HCB in the serum of the general population.
Nursing infants are at risk of developing higher levels of HCB. Tissue levels can increase 2-5 times maternal levels (68).
Volatile Organic Compounds
Only three of the VOCs detected in the blood of community residents were also found in on-site samples (toluene and 1,1,1-trichloroethane in groundwater, tetrachloroethylene and 1,1,1-trichloroethane in surface water). None of these compounds were seen in off-site samples, and the wells in the community are upgradient from the facility so no exposure pathways are present. Thus, no indication is present that people are being exposed to those compounds from the facility. This class of compounds includes many major industrial and commercial chemicals. These chemicals are ubiquitous in the environment as a result of their widespread use, particularly in fuels. Most of the population is exposed to low levels of these chemicals during the course of everyday activities. No normal ranges have been established for levels of these compounds in the blood, and very few studies have been done on levels in populations not occupationally exposed (70,71,72,73). Serum samples from the NHANES III are being analyzed for the presence of VOCs (74). See Appendix III for the results of two studies.
No potential human exposure points for toluene were found in on-site groundwater. Toluene is in widespread use in manufacturing benzene; as a solvent in paints, lacquers, and glues; and as a component of gasoline. The most common means of exposure is through occupational use and glue or solvent abuse. Among the many products that contain toluene are: gasoline, nail polish, cosmetics, rubber cement, stain removers, fabric dyes, inks, aviation fuels, adhesives, and cigarette smoke. Toluene does not persist in the environment but tends to evaporate readily. Most toluene leaves the body within 12 hours of exposure (75,76,45).
Exposure to levels of toluene in the range of 100-500 ppm has resulted in central nervous system symptoms such as fatigue, confusion, incoordination (lack of coordination), and decreased reaction time. Exposure to low concentrations does not appear to cause any systemic effects. Toluene does not have the hematopoietic (the blood system) effects of benzene. Exposure to very high doses in animals has resulted in some depression of immunological function (77). Solvent abuse during pregnancy has resulted in a syndrome of Toluene Embryopathy (a group of birth defects--including mental retardation and some facial defects--occurring in children whose mothers abused solvents during pregnancy) (78).
Xylenes were not detected in on-site groundwater, and no completed exposure pathway for xylenes has been identified. Xylene, a mixture of the ortho, para, and meta isomers, is widely used as a solvent and to manufacture organic compounds. Xylene is found naturally in petroleum and coal tar and is produced in forest fires and cigarette smoke. It is also used in paint, lacquer, varnish, ink, dyes, adhesives, cements, cleaning fluids, gasoline, and aviation fuel. Xylene is used in leather processing and to manufacture hydrogen peroxide, perfumes, insect repellents, epoxy resins, pharmaceuticals, and coatings for fabric (45).
Exposures to levels of xylenes in the range of 100-300 ppm can cause giddiness, anorexia, nausea, mucous-membrane irritation, and slight drunkenness (increased reaction time, memory impairment) (76,79). Exposure to low levels of xylenes (< 5 ppm) has not been shown to have any adverse health effects.
No completed pathway for ethylbenzene from the site has been identified. Ethylbenzene occurs naturally in coal tar, petroleum, and cigarette smoke. It is a component of paints, inks, insecticides, and gasoline and is used to manufacture synthetic rubber. The highest environmental exposures occur in people who use self-service gas pumps, reside near gas stations or highways, and in smokers (80,45). Ethylbenzene leaves the body fairly quickly, so serum levels tend to reflect recent exposure. Chronic exposures to concentrations of >100 ppm have been noted to result in fatigue, sleepiness, headache, and mild mucous membrane irritation (76). Ethylbenzene is a defatting agent, so it may result in dermatitis (inflammation of the skin) from long-term skin exposure. No data exists linking ethylbenzene to increased cancers in humans. EPA classifies it as a Class D carcinogen (not classifiable as carcinogens because of a lack of information).
Tetrachloroethylene was detected in the groundwater beneath the site; however, the human exposure pathway is not complete (see pathway analysis section). Tetrachloroethylene (PCE) is widely used as a solvent, degreaser, and dry cleaning agent. Consumer products that may contain PCE include auto brake fluid, suede protectors, paint removers, water repellents, silicone lubricants, belt lubricants, certain aerosol cleaners, fabric finishers, spot removers, adhesives, and wood cleaners. The general population in the United States is frequently exposed to PCE in ambient air (81).
PCE has been found in drinking water throughout the United States. One attempt to correlate PCE concentrations in drinking water with concentrations in serum indicated that PCE was not detected in serum unless concentrations in water exceeded 200 µg/L (82). PCE has been shown to be carcinogenic in animals. Data from humans have been determined to be inadequate to assess the risk (81). Exposures to levels of PCE of 100 ppm in air resulted in such effects as mucous membrane irritation, facial flushing (redness), headache, somnolence (sleepiness), and slurred speech. Prolonged exposures to higher levels have resulted in peripheral neuropathy (nerve damage in the extremities), CNS depression, and liver damage (76).
No completed pathway for trichloroethane from the site has been identified. The use of trichloroethane (TCA) has been increasing as a substitute for carbon tetrachloride. It is used as a degreaser, metal cleaner, dry-cleaning agent, and propellant (45). Exposure to concentrations around 350 ppm has resulted in impaired psychomotor function. Levels of 900-1000 ppm have caused light-headedness, incoordination, eye irritation, and disequilibrium (lack of balance) (76).
Very high levels can cause cardiac sensitization to epinephrine. Trichloroethane has not been determined to be carcinogenic. A recent epidemiology study of adverse pregnancy outcomes in women potentially exposed to TCA in drinking water at concentrations up to 1,700 ppb failed to determine any excess adverse outcome that could be attributed to the exposure (83).
Dichlorobenzene has not been identified in the surface or groundwater at the site. Dichlorobenzene is in widespread use as a moth killer and block room deodorant. Eye and nose irritations are noted at levels of 50-80 ppm. Higher levels can cause headache and dizziness. Extremely high levels have caused death (45,76,84). Although dichlorobenzene has been shown to be carcinogenic in animals, human data on carcinogenicity are insufficient. The primary exposure for the general population is inhalation of indoor air after use of products containing the substance.
Styrene has not been identified in the surface or groundwater at the site. Styrene is used to produce plastics. Industries that use styrene in their operations are the most important source of exposure to the compound. Other sources of exposure include tobacco smoke, automobile exhaust, and foods packaged in polystyrene containers (85).
Compounds in Hair Analyses
In addition to the serum samples, hair analyses for trace elements were conducted on nine persons in the community. The use of hair analysis to indicate internal or external human contamination from trace element pollutants has been the focus of much research. It has the advantage of being non-invasive, easy to transport and store, and provides a historical perspective on trace element concentration in the body. Once elements are deposited in the hair root, they are bound in the hair shaft permanently. Many problems are associated with the use of hair analysis as a tool to diagnose contamination. The results may vary with different sites on the scalp, different methods of collection or storage, different ways of sample preparation, and with the use of shampoos, hair sprays, bleaches, or dyes. In addition, variations in the concentration of trace elements have been associated with a person's age, gender, hair length, and hair color (86-101). Some studies have shown a seasonal variation of elements such as cadmium, lead, and zinc (88,90). One study using autopsy samples found mercury the only element in which concentrations in hair correlated well with concentrations in internal organs (87). Information on these factors must be taken into account when interpreting the results of hair analyses. Those results are evaluated in the Health Outcome Data Evaluation section.
B. Health Outcome Data Evaluation
Health outcome data were not available for the local area around the site. Available data on the county can provide a broad general indication of the health status of the population in the county where the facility is located. Births exceeded deaths in Sumter County by almost 3 to 1 as of 1984 (1,781 births, 641 deaths) (8). The Sumter County infant death rate was 18.0 per 1,000 live births, compared with a state average of 14.7 infant deaths per 1,000 live births and a national average of 10 infant deaths per 1,000 live births (102). In some studies, the infant death rate has been shown to be a fairly sensitive indicator of socioeconomic, environmental, and health care factors. Nationally the infant mortality (death) rate for blacks is almost double the infant mortality (death) rate for whites. The high infant mortality (death) rate associated with minority populations is a result of several public health factors, including poor prenatal nutrition, lack of access to prenatal care, and poor maternal health. Therefore, the infant mortality rate in Sumter County may be consistent with nationwide populations having large minority subpopulations.
Seven cases of occupational illness related to direct contact with wastes were reported by GSX in an Exposure Information Report submitted to EPA in August 1985 (10). Six cases involved direct skin contact with wastes. None of the incidents was a lost-time accident (accidents that required loss of time from work). Occupational lung disease has been reported in a few persons who worked at the "kitty litter operations" at the site.
Local residents have been examined as a group on two occasions in the past for evidence of effects from possible exposure. The group examined was not randomly selected from the population living closest to the landfill so selection bias (an error due to differences in the characteristics of the people who are studied and those who are not) is possible. A group of children from the community was examined at the Department of Pediatrics at the Medical University of South Carolina. No toxicological studies were performed at the time of these exams. All exams were conducted on September 10, 1986. None of the children was below the 25th percentile (from growth charts constructed by the National Center for Health Statistics) in height or weight. The predominant complaints of these children were rash, eye irritation, and hair loss. The diagnoses of the children were consistent with common conditions in this area of South Carolina (insect bites with secondary infection, fungal infections [tinea versicola], ringworm, scarring from trauma, and allergic skin disorders [atopic dermatitis]). Hair loss was attributed to a fungal infection of the scalp (tinea capitis) and tight pulling or braiding of the hair (tension alopecia) (19).
CASE (Citizens Asking for a Safe Environment) wanted a second opinion on the physicals, so a group of 21 local residents was taken to Dr. Allan Lieberman, the Director of the Center for Ecologic Medicine in Charleston, South Carolina (103). Results of these exams are presented in Tables 3-5.
The general physical and laboratory results are similar to health problems experienced by rural,
lower socioeconomic groups. In 1980, it was estimated that 17% of rural populations lived in
poverty. Conditions in these areas such as poor sanitation, poor nutrition, and isolation from
health services has an adverse impact on health. People living in agricultural areas have exposures
to a wide number of diseases that are shared between animals and humans (zoonotic diseases).
The agricultural environment has pollens, molds, grain dusts, and animal danders, which are
excellent agents for producing allergic reactions in the lungs. In addition, there are a variety of
skin problems that are more common in agricultural areas because of contact with irritating
substances (such as plants like tobacco or pesticides), damage from sun exposure, infections, and diseases carried by insects.
| Family History: Atopic Diseases Migraines |
Present Symptoms: Congestion Rash Headaches "Nervousness" |
| Personal History: Atopic Diseases Hair Loss Depression Migraines |
Physical: Enlarged Turbinates Scars Adenopathy Rash |
| Source: Reference 115 | |
| Study: | Abnormal Findings: |
| SCMA: 14 studies. | |
| Cholesterol, Triglycerides | 2 were above 200 (nonfasting) |
| Glucose | 1 was 148 (nonfasting) |
| Gamma-Glutamyl Transpeptidase | 2 with levels above 90 (Both Adults) |
| Potassium | 3 with levels just below normal range (3.3) |
| Hematology: 11 studies. | |
| Red Cell Counts | 4 were less than 4.00 |
| Hemoglobin | 3 less than 11.0, 3 between 11.0 and 12.0 |
| Hematocrit | 2 less than 35.0 4 between 35.0 and 36.0 |
| Mean Corpustular Volume | 2 less than 80 |
| Mean CH | 2 less than 25, 1 was above 34 |
| MCHC | 1 less than 31 |
| Platelets | 1 less than 140,000 1 above 450,000 |
| White Cell Counts | 1 was less than 4300 |
| Lymphocytes | 4 children had counts less than 3000 |
| Eosinophils | 2 had counts above 1000 |
| Lymphocyte Subsets: 18 studies. | |
| 1 had values felt to be out of range due to technical artifact | |
| 2 had values consistent with a viral infection | |
| 1 had elevation of OKT4 (4/8 ratio of 3.9) | |
| 1 had elevation of percentage of total t-cells | |
| Source: Reference 103 | |
| Eighteen individuals (11 children, 7 adults) were studied for 42 different compounds (includes 10 types of PCBs). | |||
| Number with Detectable Levels |
Range (ppb) | Mean (ppb) | |
| DDE | 1.9 - 99.4 | 16.18 | |
| DDT | ND - 3.6 | 1.21 | |
| Total PCBs * | ND - 4.2 | 1.00 | |
| Toluene | ND - 3.7 | 0.96 | |
| Trans-Nonachlor | ND - 1.0 | 0.29 | |
| Tetrachloroethylene | ND - 1.9 | 0.56 | |
| Heptachlor Epoxide | ND - 2.1 | 0.44 | |
| HCB | ND - 0.7 | 0.14 | |
| Xylenes | ND - 15.2 | 1.85 | |
| 1,1,1-Trichloroethane | ND - 3.5 | 0.58 | |
| Beta-BHC | ND - 1.1 | 0.21 | |
| Ethylbenzene | ND - 3.2 | 0.28 | |
| DDD | ND - 0.3 | 0.02 | |
| Dichlorobenzene | ND - 3.1 | 0.17 | |
| Styrene | ND - 0.6 | 0.03 | |
| * Most common PCBs were 2,2',3,4,4',5' Hexa; 2,2',4,4',5,5' Hexa; and 2,3',4,4',5
Penta.
Source: Reference 103 | |||
Hair loss can have a variety of causes. Alopecia areata (hair loss without other symptoms) is associated with conditions such as atopy, Down's Syndrome, and thyroiditis; although, its cause has not been identified (104). Other causes of hair loss include high fever, severe infection, severe psychological stress, hypothyroidism, crash diets, certain drugs, and heavy metals (105). Several children had scarring of the lower extremities from previous rashes. The most common description included blistering and pustule formation. Attempting to ascertain the etiology of a rash from this description is difficult. Many chemicals can cause contact dermatitis (106). The description did not include the primary lesions of chloracne: comedones and cysts (107). Many infectious causes of rashes also have these features (108). Several persons had mild anemia. The only liver function abnormalities were the isolated elevation of Gamma-Glutamyl-Transpeptidase in two adults. No history of alcohol use is known among the people. Tests of kidney function were normal in all cases. The lymphocyte studies did not show markedly abnormal results. Test results were consistent with the individuals' medical histories and present symptoms.
Levels of the above compounds in this group are consistent with levels seen in studies of general populations. Two persons had serum levels of xylene greater than twice the mean of the NHANES III results (74). One person lived more than 5 miles from the site, so it is not evident how this exposure could be related to the site. The health outcomes observed in these people are consistent with the general symptoms of people exposed to VOCs (benzene, xylenes, styrene, ethylbenzene, toluene) such as headaches and rash. Many people reported using kerosene heat, living in mobile homes, and living with smokers, all of which are sources for several VOCs (109).
Analysis for elements in hair samples was carried out on nine persons. Information was not
available on the laboratory preparation methods or on the individual characteristics (such as hair
color, use of dyes or permanents) that influence results; therefore, no clinical evaluation of these
results is possible. Results of these analyses are presented in Table 6.
| TABLE 6. Hair Analyses Results, GSX landfill, Sumter County, South Carolina | |||
| Element | Notes | ||
| Zinc | 1 value > 320 | ||
| Lead | 1 value > 30 | ||
| Cadmium | 1 value > 2 | ||
| Copper | 2 values > 90 | ||
| Manganese | |||
| Iron | 1 value > 70 | ||
| Aluminum | 2 values > 80 | ||
| Source: Reference 103 | |||
C. Community Health Concerns Evaluation
During the site visit in May 1990, ATSDR representatives explained to a resident that a public health assessment is necessary to determine which, if any, exposure pathways are completed, and which persons may have been exposed. Proceeding directly to a health study without conducting a public health assessment may result in unnecessary expense or in failure to include all potentially exposed persons. During the public availability session in March 1991, a few community members expressed a desire to be relocated if they are being exposed.
The Department of Psychology at the University of South Carolina conducted a study in the area entitled "Coping with an Environmental Stressor: Perception of Risk, Attribution of Responsibility, and Psychological Distress in a Community Living near a Hazardous Waste Facility" (110). The study was a survey of residents over 18 years of age living within a 25-mile radius of the GSX Landfill. This study indicated an increase of psychological distress and perception of risk to health in residents of the Rimini community. An ATSDR review of this study indicated several biases and design flaws.
Analysis of the health outcome data for the area indicates excess psychological distress in the community. The toxicological studies conducted on people in the Rimini community indicate the community is exposed to low levels of PCBs, DDT, and VOCs; however, these compounds are ubiquitous in the environment and the levels were not significantly greater than levels in non-occupationally exposed groups. The information is therefore not sufficient to attribute these contaminants to the landfill. Health outcome data are consistent with previous studies that have not been able to link residential proximity to chemical waste with major diseases or illnesses, but have linked high levels of stress and anxiety and feeling of poor overall health with the presence of hazardous wastes in the community (111,112,113). Health outcome data do not indicate whether the community is presently being exposed to hazardous materials from the landfill; however, when health in the broadest sense is considered, the presence of the landfill can be said to have had a negative effect (114,115).
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