PUBLIC HEALTH ASSESSMENT
ROSS METALS INCORPORATED
ROSSVILLE, FAYETTE COUNTY, TENNESSEE
The Ross Metals, Inc. site is in Rossville, Fayette County, in western Tennessee. The site began operations in 1978. Activities at the site involved the reclamation of lead from spent batteries and other lead containing items. This activity as well as improper storage and disposal practices lead to the contamination of several environmental media with lead being the primary contaminant. Operations on the site ceased in June 1992.
Based upon the data and information reviewed by the Agency for Toxic Substance and Disease Registry (ATSDR) has concluded that: Ross Metals, Inc. site is a Public Health Hazard. This is due mainly to the presence of physical hazards and the large piles of slag present on the site.
ATSDR currently considers the residential area adjacent to the site to be a No Apparent Public Health Hazard. The time-critical removal conducted by the U.S. Environmental Protection Agency (EPA) has removed the lead contamination that formerly was in the residential area next to the site and has minimized the potential for on-site contaminants to migrate into the residential area. Current exposure to residents living along Railroad Street from on-site runoff was evaluated in the Exposure Investigation (EI). The blood lead levels of adults and children that currently reside next to the site were below the current action levels recommended by the CDC. One of the six participants, a three year old child had a slightly elevated blood lead level; this child is not a permanent resident of the home. None of the soil and dust samples tested in this EI contained lead in excess of the EPA screening level. The results of the environmental sampling conducted during the ATSDR exposure investigation did not find any arsenic and antimony surface soil contamination in the residential area at levels of health concern.
In the past, workers at the facility, while it was in operation, and residents near the site were exposed to lead at levels of health concern. Therefore, both the RMI site and the residential area adjacent to the site are considered as a Public Health Hazard in the past. Biological monitoring of the workers indicates that they were exposed to lead above levels at which adverse health effects could possibly occur. Possible adverse health effects that could possibly occur in the workers are increased blood pressure, reduced production of sperm, earlier on-set of menopause, and changes in enzyme function in the blood.
Children and pregnant women that resided near the facility when it was in operation were also exposed to lead. Biological monitoring of the children indicate that some of them were exposed to lead above levels above the Centers for Disease Control and Prevention (CDC) action levels. Some of the children required medical treatment to reduce the amount of lead in their blood (chelation). However, due to the conditions of the homes and properties near the site, it cannot be said that these exposures were due solely to the Ross Metals, Inc. site. The residents not owning homes along Railroad Street moved soon after operations ceased at the site. Possible effects that may be caused by elevated blood lead in children include decreased IQ and impaired hearing and growth. In addition, some neurological effects may occur and persist in the exposed children, even through adulthood. The possible symptoms of the neurological effects include poor memory, difficulty reading and concentrating, depression, and sleep disturbances
Adverse carcinogenic or non-carcinogenic health effects are not expected to occur because of exposures to antimony and arsenic found in the on-site and off-site surface soils.
ATSDR has made recommendations to cease or reduce possible exposure on and near the Ross Metals, Inc. National Priorities List site.
The Agency for Toxic Substances and Disease Registry (ATSDR), located in Atlanta, Georgia, is a federal agency within the U.S. Department of Health and Human Services. ATSDR, under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) conducts public health assessments for sites the U.S. Environmental Protection Agency (EPA) proposes for the National Priorities List (NPL). EPA announced its proposal to list the Ross Metals, Inc. site in October 1996. The site was added to the NPL in March 1997. Therefore, ATSDR has, under its mandate, evaluated the public health significance of this site by considering whether adverse health effects are possible and has recommended actions to mitigate possible future exposure.
The Ross Metals, Inc. site (RMI) is an inactive secondary lead smeltering plant located on a five acre tract of land in Rossville, Fayette County, Tennessee (1). The site is situated at 100 N. Railroad Street. The west side of the site is bordered by a wastewater treatment facility, the north side by woodlands and wetlands, the south by the Southern Railroad tracts and the Kellogg Corporation property, the east side by wetlands, and the southeast (along Railroad Street) by residences (Appendix A, Figure 1).
Numerous inspections and sampling investigations have been conducted at the site (2). From 1979 until December 1988, blast slag (a glassy residue generated by the melting of metallic ores) was disposed of in the on-site landfill located on the north portion of the RMI site. In November 1988, RMI submitted a Resource Conservation Recovery Act (RCRA) part B application (3) for disposal of what was thought to be nonhazardous blast furnace slag into an on-site landfill. EPA conducted a sampling investigation on December 7, 1988 to determine if the waste generated by the facility should be regulated. On May 9, 1990 EPA conducted another sampling investigation to determine if the smelting and land filling activities at the site were causing adverse environmental impacts. In June 1990 the RCRA part B application request was denied when blast slag was classified by EPA as a hazardous waste.
In September 1990, a Complaint and Compliance Order (4) was issued against RMI. EPA conducted a site investigation during the week of November 28, 1990. During the site investigation, samples were taken from the landfill and analyzed for metals. Results indicated lead contamination in all media sampled. The site ceased operations in 1992.
Houses along Railroad Street not owned by the residents were condemned by the city's building inspector beginning in June 1994 thru December 1998, because of the unstable structural conditions. As of April 1999 there were four residences being occupied along Railroad Street.
EPA conducted a Superfund Time-Critical Removal of soil because of high concentrations of lead, from October 1994 through June 1995. During the removal, soil in the residential yard adjacent to RMI was sampled. In May 1995, EPA requested ATSDR review and comment on soil samples taken from the residential yard next to the RMI facility. ATSDR was asked to determine if a health threat due to exposure or contact with lead constituted the need for a removal action of the soil at the residential yard. ATSDR determined that the level of lead (950-1,740 milligrams per kilogram [mg/kg]) in the soil exceeded the recommended levels that would be protective of human health. ATSDR recommended that the residents be disassociated from the contaminated soils (5). In June 1995, an unspecified quantity of soil was removed from the residential yard by EPA.
In December 1995, EPA asked ATSDR to suggest soil sampling strategies that could be used to assess the health impact of possible lead contamination at the rented houses along North Railroad Street. At that time ATSDR determined that lead contamination in residential soil near the site had not been adequately characterized (5). ATSDR recommended that environmental sampling should be done at the residences near the site with special emphasis being placed on homes that were occupied by children with elevated blood lead levels.
EPA conducted a Superfund Preremedial Investigation in June 1995 and a Superfund Remedial Site Characterization (SRSC) in November 1996. In January 1997, EPA held a public meeting in Rossville to address concerns about the site.
In June 1997, ATSDR headquarters staff visited the site area. At that time they got an overview of the site from State health and environmental officials. They also gathered additional information which could be used in the preparation of this and future documents. ATSDR staff were informed that some community members were concerned about possible exposure to contaminants (mainly lead) which may have emanated from the site. In an effort to address these concerns, staff from ATSDR's Division of Health Assessment and Consultation (DHAC) Superfund Site Assessment Branch (SSAB) presented a proposal to DHAC's Exposure Investigation and Consultation Branch (EICB). The proposal was accepted and an exposure investigation was conducted in the area in May 1998.
In addition to the June 1997 site visit, ATSDR headquarters staff, also visited the area in April 1998 to explain the exposure investigation to the local citizens during a public meeting. In May 1998, they visited the area to conduct the actual exposure investigation.
During the 1997 site visit, ATSDR observed that there were signs of dumping on the west side of the property and in the area of the former landfill. A map of the operational area of the site is included in Appendix A (figure 2). The fence surrounding the operational area of the site was not structurally sound to provide adequate security to keep unauthorized persons off of the site. The front and back gates had been damaged. There was a large hole in the fence on the east side of the property. Multiple physical hazards exist on the site including old deteriorating process equipment, dilapidated buildings and towers, open buildings with large piles of slag, deep standing water in old towers, and unmarked drums and containers (some are possibly left from past and current remedial activities). Other observations made during the site visits are noted throughout this report.
The town of Rossville is located in Fayette County, Tennessee, approximately 10 miles east of Memphis. The population of Rossville, based on 1990 Census data, is approximately 291 persons comprising 111 families.
Approximately 118 persons live within a one-mile area around the site boundary. The population is comprised of 38% black or other minority races. Children six years of age or younger comprise 11% of this population (34 people) (Appendix A, Figure 3). The majority the residents living along Railroad Street relocated after operations at the site ceased and the homes not owned by residents were condemned by the city building inspector. The closest residential area to the RMI site is along Railroad Street. At the time of ATSDR's exposure investigation, only one home in the immediate vicinity to the RMI site was occupied. Approximately five people live in the home on a full-time basis. As of April 1999, four homes along Railroad Street were occupied.
The RMI site is zoned light industrial. It is located in the 100-year floodplain of the Wolf River (3). According to the Mayor of Rossville, the property on which the site is located was a park at which the residents frequently gathered for picnics.
Land use at the southeast corner of the site is primarily residential. Most houses along Railroad Street near the site are in poor condition. ATSDR was informed by the mayor of Rossville that these residences are on land owned by Ross Metals. Based upon information obtained by ATSDR, children lived in some of the residences. In the past, some of the children living in the residences had high blood lead levels. A couple of the children had to be hospitalized and chelated to remove the lead (5). All of the homes, except one, were condemned by town officials. Some of those homes are currently being occupied. Railroad tracks are located directly to the south of the site. The Kellogg Corporation which packages breakfast foods is located south of the site on the opposite side of the railroad tracks. A wastewater treatment facility is located on the land to the immediate west of the site. Land to the north and northeast is undeveloped woodlands and wetlands. The Wolf River is located 0.5 to 1-mile north of the site. It is the nearest receiving tributary.
Natural Resource Use
The site is located in western Tennessee and characterized by unconsolidated near-surface sands, silts, and clays. The Memphis aquifer is an important water bearing zone. Groundwater in the unconfined portion of the Memphis aquifer generally flows to the west. Although the regional groundwater flow is toward the west, monitoring wells established on and near the RMI site indicate that groundwater flow in the area is to the north towards the Wolf River. There are two municipal supply wells and three industrial production wells known to be located within 1/4-mile of the site. These wells are known to be screened in the Memphis aquifer. The wells may affect site groundwater flow when they are pumping. The municipal wells are tested annually for lead and copper. No signs of contamination have been found.
ATSDR was informed that residents living along North Railroad Street, adjacent to RMI, were using private wells until 1995. They were then placed on the Rossville community water system. All of the private wells were shallow and most were not drilled by professionals. All of the private wells have since been closed (capped or had the pipes removed to prevent future use). Municipal wells for the city of Rossville are tested annually for lead and copper. No signs of contamination have been found in the municipal wells. One of the lagoons at the wastewater treatment facility adjacent to the site was taken out of production because of lead contamination from the site.
The Wolf River is located ½ - 1-mile north northeast of the site. ATSDR was told by State officials that the Wolf River in the area of the site is not used much for recreational purposes. Surface water runoff at the RMI site drains generally toward the Wolf River. However, EPA removed an unknown quantity of soil from a residential yard adjacent to the site. The soil was not replaced behind the house, therefore creating a gradient for possible drainage of contaminants from the site onto the nearby residential property. A gully has formed behind a residence that is used as an unlicensed day care facility. According to State officials, based on observation, there is not enough water in the gully for wading purposes but it is muddy enough for children to make mudpies.
Health outcome data may help determine whether the incidence rates of certain adverse health effects are higher than expected in the area of the Ross Metals, Inc. site. This section identifies available, relevant, databases and information sources. The databases and sources will be evaluated in section B of the Public Health Implications section of this document.
During ATSDR's visit to the RMI site, documentation was discovered which showed worker's had elevated blood lead levels. The data found was part of the site's monitoring plan.
In order to determine whether or not the community surrounding the site is currently being adversely impacted, ATSDR initiated an exposure investigation in May of 1998. The results of the investigation will be discussed in the Health Outcome Data Evaluation subsection of this document.
During the June 1997 site visit, ATSDR staff contacted officials of the Tennessee Department of Environment and Conservation (TDEC), the Tennessee Department of Health (TDOH), and the Rossville Mayor's Office to gather information regarding health concerns about the site. These officials were not aware of any recent complaints from the public related to health concerns due to contaminants at the site. On April 21, 1998, ATSDR staff attended a public meeting in Rossville sponsored by the Tennessee Department of Environment & Conservation. The following question related to the site was asked:
Have residents been affected by heavy run-off from the RMI site created from the soil removal work done by the EPA?
In order to respond to this community concern, ATSDR conducted an exposure investigation near the site in May 1998. The result of the investigation will be discussed in the Health Outcome Data Evaluation subsection of this document.
In order to determine what environmental contaminants may be a concern, ATSDR has evaluated all of the available environmental monitoring data. Environmental data was taken from the site investigations data summary (2). Screening values were used as a basis for evaluation of the data and to determine which of the contaminants should be looked at more closely. Environmental screening values are health-based estimates of concentrations in environmental media below which no known or anticipated adverse health effects should occur. The values allow an adequate margin of safety. Appendix B and the Public Health Implications section of this document contain a list and descriptions of the screening values used in this public health assessment.
A contaminant is selected for further evaluation if the contaminant in a valid environmental sample exceeds environmental screening values or normal background levels. Environmental screening values for ATSDR public health assessments are contaminant concentrations that are found in specific media (air, soil, and water). The values are designed to be conservative and non-site specific, and therefore protective of all probable exposures. Their intended use is only to screen out contaminants which do not need further evaluation. They are not intended to be used as clean-up levels. The presence of a contaminant on Tables 1-7 of Appendix B does not mean that either exposure to the contaminant or adverse health effects has occurred or will occur. Inclusion in the tables indicates only that the potential for human exposures to the selected contaminants and the potential for adverse human health effects as a result of any exposures to the selected contaminants will be discussed in more detail in other sections of this public health assessment.
The environmental investigations conducted by the Region IV EPA have identified various contaminants in on-site surface soil and groundwater. This part of the public health assessment will identify contaminants detected above environmental screening values or normal background levels in the environmental media. Missing and inconsistent data will be discussed in the data gaps subsection.
1. Surface Soil
Operational Area (Appendix B, Table 1)
Surface soil samples (0"-6" deep) were collected during EPA's sampling investigations. One of those investigations was the Superfund Remedial Site Characterization (SRSC) which occurred in 1996. During that investigation, samples were taken in the ditch and grass areas at the southeast portion of the RMI site. These samples were analyzed for metal content. The concentrations of most of the metals did not exceed ATSDR's environmental screening values or normal background levels. Arsenic at a maximum concentration of 230 mg/kg soil exceeded ATSDR's environmental screening values for noncarcinogenic and carcinogenic effects. The concentration of antimony was more than 10 times greater than ATSDR's environmental screening value. Lead was detected at a maximum concentration of 43,000 mg/kg. ATSDR does not have an environmental screening value for lead in soil. This concentration does however exceed EPA's action level for lead in soil.
Landfill Area (Appendix B, Table 2)
Soil samples were collected from the landfill area of the RMI site during the SRSC and analyzed for metal constituents. Antimony and arsenic were detected at maximum concentrations of 75 mg/kg and 76 mg/kg, respectively. Lead was detected at a maximum concentration of 15,000 mg/kg.
On July 1, 1997 the State of Tennessee Environmental Epidemiology Program (EEP) collected four surface soil samples from the landfill area of the site. These samples were analyzed for lead content. The concentration of lead in the samples ranged from 3,830 mg/kg to 50,800 mg/kg. The highest concentration was found in northwest portion of the landfill. This is the area where there is evidence of non-site related dumping of debris.
2. Groundwater (Monitoring Wells, Appendix B, Table 3)
Groundwater samples were collected during the EPA sampling investigations which include the SRSC, the Superfund Time Critical Removal (STCR) in 1995, and the Resource Conservation Recovery Act (RCRA) investigations in 1990. The samples were analyzed for metal content. The highest on-site levels of metals within the operation area were arsenic (110 micrograms per liter (g/L)), lead (500 g/L), and manganese (5,600 g/L). Groundwater contamination at the site has not been characterized fully.
3. Waste Material
In November 1990, a RCRA case development investigation/evaluation was conducted (6). Plastic chips were collected from a semi-trailer next to the battery decasing building on the RMI site. In addition, two slag samples were collected from the slag pile on the landfill and from the slag bin near the furnace building. The plastic chips contained lead at a maximum concentration of 2,400 mg/kg and the slag samples contained lead at a maximum concentration of 82,000 mg/kg. The levels are above regulatory standards.
4. Data Gaps
Based upon observations and other data (including dust/wipe sampling) it is likely that lead and other metals were dispersed from the site via wind-borne transport. Air sampling data are not available, because the vast majority of air emissions occurred in the past.
The environmental investigations conducted by EPA have identified various contaminants in off-site surface soil, groundwater, and surface water. This part of the public health assessment will identify contaminants detected above environmental screening values and normal background levels in the various environmental media. Missing and inconsistent data will be discussed in the data gaps subsection.
1. Surface Soils (Appendix B, Tables 4-5)
In 1990, during the RCRA investigations, composite surface soil samples were taken. The highest concentrations of metals were found in the area along the northern boundary of the landfill. Antimony (22 mg/kg) and arsenic (20 mg/kg) were found at levels equal to or exceeding ATSDR screening values. The maximum concentration of lead in the area was 2,400 mg/kg.
Surface soil samples were collected during the EPA sampling investigations which included the SRSC in 1996. The highest off-site levels of metals were found in the woodland area to the northeast of the site. This is in the area of site drainage toward the Wolf River (the nearest receiving tributary). Lead was detected at a maximum concentration of 12,000 mg/kg. Arsenic and antimony were detected at maximum concentrations of 86 mg/kg and 51 mg/kg, respectively. These concentrations exceeded ATSDR's environmental screening values. The areas of highest metal contamination were cleaned up by the 1994 and 1995 EPA Time-Critical Removal.
Surface soil samples were collected by ATSDR in May 1998 as part of the exposure investigation. These soil samples were analyzed for lead content. The maximum concentration of lead detected in the soil samples was 230 mg/kg. This maximum concentration did not exceed EPA's action level for lead in soil.
2. Groundwater (Monitoring Wells, Appendix B, Table 6)
Monitoring wells were installed off-site to provide data regarding groundwater flow and quality. Samples were collected during the SRSC in 1996 and analyzed for metal content. The maximum concentrations listed for antimony (20 g/L) and arsenic (40 g/L), are the minimum quantitation limits. Lead (1,400 g/L) and manganese (3,700 g/L) exceeded ATSDR screening values and guidelines.
3. Surface Water (Appendix B, Table 7)
The RMI site lies within the 100-year floodplain of the Wolf River. Surface water samples were collected during EPA site investigations in the woodland and wetland areas near the northwest, north, and northeast edge of the landfill. The samples were analyzed for metal content. Several of the metals were present at concentrations which exceeded ATSDR screening values and environmental guidelines. The maximum concentration of lead in surface water (16,000 g/L) was found near the northern boundary of the RMI site during the Time Critical Removal Investigation in 1995.
In preparing this public health assessment, ATSDR relies on the information provided in the referenced documents. We assume that adequate quality assurance and quality control measures were followed regarding the chain of custody, laboratory procedures, and data reporting. The analyses, conclusions, and recommendations in this health assessment are valid only if the referenced documents are complete and reliable.
During the June 1997 site visit, multiple physical hazards were noted. Buildings throughout the site are old and dilapidated. Some of the buildings are being used for storing large piles of slag and rock. Due to their poor condition, these buildings do not provide adequate cover to prevent the contaminated materials from being dispersed by wind and rain. Some of the storage structures were found to contain standing water. This could pose a drowning hazard for a child who may wander onto the site. Old, contaminated process equipment is stored at the northwest portion of the site's operational area. This equipment could pose an exposure hazard as well as a safety hazard in its current condition. Numerous fifty gallon drum containers are located throughout the site. They may contain hazardous materials. The fence surrounding the site is not structurally sound and therefore does not provide adequate security to keep unauthorized persons off the site.
A removal action occurred during the Summer of 1998. EPA had its contractors come in to correct the some of the deficiencies noted above. On June 17th to 20th, damaged portions of the roof of one of the buildings covering slag piles was removed. The fence line areas were cleared and the slag piles were covered with tarpaulin. The perimeter fencing was installed the following week.
In April 1999, staff from TDEC visited the RMI site. According to staff, the buildings (structures) containing the slag piles are not structurally sound to provide adequate cover for the slag piles. There is evidence that runoff during rain events from the slag is occurring. This could pose an exposure hazard to anyone not wearing personal protective equipment or taking the appropriate precautions against exposure. Signs of trespassing, as evidenced by discarded coolers and beer cans, were present.
To identify other possible facilities that could contribute to the contamination at the Ross Metals, Inc. NPL site or the discharges from such facilities that could increase an individual's exposure to site-related contaminants, ATSDR searched the 1987 to 1992 Toxic Chemical Release Inventory (TRI) database.
Several limitations of TRI data should be noted (7). The air release data in TRI may be estimates or actual measurements. Many of the reported data are estimates based on conservative (overestimated) scenarios. Consequently, the levels on emissions recorded in TRI are often biased on the high side. In addition, reporting is restricted to specific chemicals that are used or releases above specified amounts. Finally, it is believed that there have been and still are industries that do not report releases. Smaller industries may not be aware that reporting requirements exists or that they are responsible for such reports. The search of the TRI (8) for facilities in the 38066 zip code area revealed that there are no other reporting facilities which released contaminants found at the RMI site.
In this section of the public health assessment, the possible environmental exposure pathways are evaluated to help determine whether individuals have been, are being, or will be exposed to site-related contaminants. The pathways analysis consists of five elements:
- Identifying contaminants of concern possibly related to the site;
- Determining that contaminants have been/are being/will be transported through an environmental medium;
- Identifying a point of exposure (i.e., a place or situation where people might be exposed to the contaminated media);
- Determining that there is a plausible route of human exposure (i.e., can the contaminant enter the body?); and
- Identifying an exposed population (i.e., how many people, if any are at the point of exposure?).
An environmental exposure pathway is considered complete when there is good evidence that all five elements exist (9). The presence of a completed pathway indicates that human exposure to contaminants has occurred in the past, is occurring, or will occur in the future. When one or more of the five elements of an exposure pathway are missing, that pathway is considered potential. The presence of a potential exposure pathway indicates that human exposure to contaminants could have occurred in the past, could be occurring, or could occur in the future. An exposure pathway can be eliminated from consideration if at least one of the five elements is missing and will never be present. Although it is considered a conservative approach, if there is uncertainty about the site-relatedness of the contaminants of concern in an exposure pathway, the pathway will be evaluated as if the contaminants were site-related.
A. Completed Environmental Exposure Pathways (Appendix C, Table 1)
There is evidence based upon the site history, site data, and interviews with state and local officials and local residents, that people at and near the Ross Metals, Inc. National Priorities List site (RMI) were likely exposed on an intermittent basis (in the past) to contaminated air (via inhalation), on-site surface soil (via incidental ingestion, dermal contact, and inhalation), off-site surface soil (via incidental ingestion, dermal contact, and inhalation) and numerous physical hazards. Some of these exposures are likely to continue until the site has been remediated.
1. On-site Surface Soil
Persons working on or visiting the site (without proper personal protective equipment or not taking appropriate personal hygiene measures to prevent exposure) are/were likely exposed to lead and other metals in surface soil. Assuming that the maximum concentration of the contaminants found in the surface soil samples taken during the previously mentioned investigations conducted by EPA and EEP were in the top 0" - 3" of soil, workers and others could be/have been exposed to those contaminants.
Children likely played on the site. Soil ingestion is an important route of exposure for children, particularly for children younger than 6 years (10). The contaminated soil is still on the site. Therefore, trespassers and persons visiting the site may continue to be exposed to the contaminated soil in the landfill area and in various locations in the operational area of the site. In addition, there is a daycare operation in the immediate vicinity of the site. It is possible that these children could have been exposed to site related contaminants in the past (if they played on the site or played with objects taken from the site).
ATSDR does not have air quality monitoring data for the RMI site. However, during a public meeting attended by ATSDR on April 21, 1998, residents living along Railroad Street gave witness to the times they would actually leave their houses in fear because the emissions being released from site operations were so dense they thought their homes were on fire. This occurred while the facility was operational (1978-1992). Therefore it is likely people living near the site were exposed contaminants via inhalation.
During the site visit conducted by ATSDR in June 1997, particulates emitting from the slag piles stored on-site were noted. Contaminants released to the ambient air are dispersed by wind. Any contaminants from the site will disperse throughout the area. Air sampling data are not available.
Based upon ATSDR's observations and other data (including dust/wipe samples), it is very likely that people were and are currently being exposed via inhalation to lead and other metals via particulates in the air. Waste pile on the site were covered with a tarpaulin in the Summer 1998, however, should these tarpaulins dislodge, as has occurred in the past, exposure will likely continue into the future.
3. Off-site Surface Soil
Based upon data reviewed by ATSDR, surface soil in the woodlands and wetlands north and northeast of the site, as well as land to the east of the site are contaminated with metals. Although not an everyday occurrence, it is believed that some people use these areas to access the Wolf River which is located to the north-northeast of the site. In addition, residences are located on the land to the east of the site. Assuming that the maximum concentrations of these metals are in the top three inches of the soil, it is likely that people were exposed in the past to the contaminants via incidental ingestion, inhalation, and dermal contact. It should be noted that arsenic is a naturally-occurring element found in most every soil type.
In May 1998, ATSDR conducted an environmental exposure investigation. Based upon results of the exposure investigation, surface soils in the residential areas adjacent to the site do not currently appear to be contaminated with lead at concentrations above EPA's action level for lead in residential soils.
4. Waste and Physical Hazards
Large piles of lead contaminated slag, rocks, plastic chips, and other waste are stored on-site. Attempts have been made to cover these wastes and prevent wind dispersion. Should these measures fail (as has occurred in the past), persons who trespass upon or enter the site without taking appropriate precautions are likely to be exposed to the lead and other metal contaminants in the waste via dermal contact, inhalation, and possibly via incidental ingestion. Until these waste are remediated (removed from the site) it is likely that exposure will continue to occur.
B. Potential Environmental Exposure Pathways (Appendix C, Table 2)
1. On-site Subsurface Soil
Based on data from investigations conducted by EPA, subsurface soils are contaminated with metals. It is possible for former on-site workers and others to be/have been exposed to the contaminants in this medium via inhalation of fugitive dusts, incidental ingestion, or dermal contact during excavation activities or any other activity which may have resulted in disturbing soil greater than six inches below the surface. However, the frequency that this type of activity would occur is minimal. Therefore it is unlikely that people were exposed to a significant amount of metals via this exposure pathway.
2. On-site Groundwater
The extent of groundwater contamination at the site has not been fully characterized. However, analyses of groundwater samples from on-site monitoring wells indicate that the groundwater on the site is contaminated with various metals. Most of the contaminants are above ATSDR environmental screening values. On-site groundwater is not used as a potable water source. The direction of groundwater flow in the area of the site is reportedly to the north-northeast. If someone were to drill a well into the contaminated groundwater aquifer for a primary water source, exposure would occur via ingestion, inhalation, and/or dermal contact. Due to the contaminated groundwater beneath RMI, it is unlikely that anyone would be allowed to install a water supply well at the site.
3. Off-site Surface Water
Analyses of surface water in the immediate vicinity of the site indicate that surface water off-site is contaminated with various metals. It is possible for people to be exposed to site runoff while engaging in recreational activities on the land to the east of the site and in the wetlands area.
C. Non-Apparent Environmental Exposure Pathway (Appendix C, Table 3)
1. Off-site Groundwater
Monitoring wells placed off-site in the vicinity of RMI have shown groundwater to be contaminated by metals at concentrations which exceeded ATSDR environmental screening values. However groundwater flows away from residences adjacent, therefore exposure to the contaminated groundwater was unlikely.
2. Off-site Residential Surface Soil
In May 1998, in order to determine whether or not exposures of public health significance were occurring, ATSDR conducted an exposure investigation at the occupied residence near the site. Based upon data gathered during that exposure investigation, current exposures to contaminants in the surface soil of the residential yards sampled should not pose a public health hazard.
The contaminants of concern released into the environment at the Ross Metals, Inc. National Priorities List (RMI) site have the potential to cause adverse health effects. However, for adverse health effects to occur, the pathway for exposure must be completed. A release does not always result in exposure. A person can only be exposed to a contaminant if they come in contact with the contaminant. Health effects resulting from the interaction of an individual with a hazardous substance in the environment depend on several factors. One is the route of exposure; that is, whether the chemical is inhaled; consumed with food, soil, or water (ingestion); or whether it contacts the skin (dermal). Another factor is the dose to which a person is exposed, and the amount of the exposure dose that is actually absorbed. Mechanisms by which chemicals are altered in the environment or inside the body, as well as the combination (types) of chemicals are also important. Once exposure occurs, characteristics such as age, sex, nutritional status, genetics, life style, and health status of the exposed individual influence how the contaminants are absorbed, distributed, metabolized, and excreted. Together those factors and characteristics determine the health effects that may occur as a result of exposure to a contaminant. Much variation in those mechanisms exists among individuals. For example; all children mouth or ingest nonfood items to some extent. This type of behavior is known as pica. The degree of pica behavior varies widely in the population, and is influenced by nutritional status and the quality of care and supervision (9). Groups that are at increased risk for pica behavior include children aged 1 to 3 years old and children with neurologic disorders (e.g., brain damage, epilepsy, and mental retardation).
Discussion of Contaminants of Concern
Exposure to contaminants in air and on-site and off-site surface soil represent completed exposure pathways. The exposures which occurred or may have occurred due to inhalation exposure could not be estimated due to lack of air monitoring data. The methods for calculating exposure doses due to ingestion and evaluating the exposure doses are presented in Appendix D. The estimated exposure doses via ingestion for antimony, arsenic, and lead exceeded the health guidelines ATSDR uses to evaluate levels of exposures (Appendix E, Tables 1 and 2), therefore, these contaminants will be discussed further.
Antimony was found in on-site surface soil at a maximum concentration of 270 mg/kg and in off-site surface soil at a maximum of 51 mg/kg. Persons who worked on the site, trespassers, and persons residing near the contaminated areas were likely exposed intermittently. At the estimated exposure doses, adverse non-carcinogenic health effects, following long-term exposure via incidental ingestion of antimony at the maximum concentrations detected are not expected to occur in these individuals. Possible effects due to inhalation are not evaluated because of lack of air monitoring data. Studies in the literature showed no effects in humans after dermal exposure to antimony.
Information on the carcinogenic potential of antimony was not found.
People with chronic respiratory or cardiovascular diseases or problems may be more susceptible to the effects of antimony since antimony may exacerbate one or both of these health problems. Individuals with kidney dysfunction also may be more susceptible to the effects of antimony because antimony is excreted in the urine. None of these health problems were reported to ATSDR personnel by persons currently residing near the site.
Arsenic was detected in soil samples taken on-site at a maximum concentration of 230 mg/kg. It was also found in off-site soils at a maximum concentration of 86 mg/kg. The chronic oral MRL for arsenic is 0.0003 mg/kg/day. The NOAEL in humans is 0.0008 mg/kg/day. The estimated exposure doses does not exceed the NOAEL. Therefore, it is unlikely that individuals would have noncarcinogenic health effects because of long term exposure to arsenic.
Relatively little information is available on adverse health effects due to direct dermal contact with inorganic arsenicals, but several studies indicate that the chief effect is local irritation with dermatitis, with little risk of other adverse effects. The dermal contact rates which cause these effects in humans have not been quantified, but a similar type of irritation was produced on mice exposed to 2.5 mg arsenic/kg as sodium arsenite.
EPA classifies arsenic as a Class A known human carcinogen by the oral and inhalation routes. Epidemiologic studies of people exposed to arsenic in Taiwan indicate that exposure to arsenic is associated with skin cancer. Based on that and other studies, the EPA considers arsenic to be a human carcinogen. The EPA has calculated a cancer unit risk factor, 1.75 (mg/kg/day)-1, which can be used to estimate the probability of excess cancer risk for a lifetime of exposure to arsenic. Cancer risks for exposure were estimated based on the maximum concentration of arsenic in the contaminated media. The cancer effect level (CEL) for arsenic in humans is 0.009 mg/kg/day. The CEL is higher than what the workers or local residents were most likely exposed to. Therefore it is unlikely that the workers or local residents will develop cancer because of site related arsenic.
No studies were found regarding unusual susceptibility of any human sub-population to arsenic. Since the degree of arsenic toxicity may be influenced by the rate and extent of its methylation in the liver, it seems likely that some members of the population might be especially susceptible because of the lower than normal methylating capacity. This reduced capacity could result from dietary deficiency of methyl donors such as choline or methionine. Liver disease does not appear to decrease methylation capacity in humans, at least not at low levels of arsenic exposure.
Lead was detected in on-site surface soils at a maximum concentration of 50,800 mg/kg and in off-site surface soils at a maximum concentration of 12,000 mg/kg. Former on-site workers as well as children from residences near the site have been shown to have elevated blood lead levels in the past. ATSDR has no MRL and EPA has no RfD for lead. The estimated exposure doses for each of the target populations exceeds the LOAEL for neurological effects in monkeys (0.05 mg/kg/day).
Exposure to lead causes a wide range of effects. The level of lead in blood is a good measure of recent exposure, and it also correlates well with health effects. Children are especially sensitive to lead, and many of its effects are observed at lower concentration in children than in adults. Levels of 10 µg/dL and perhaps lower in children's blood have been associated with decreased IQ, impaired hearing and growth, and some neurological effects. The neurological effects have been shown to persist after exposure has ceased and blood lead levels have returned to normal. The reported symptoms of the neurological effects include poor memory, difficulty reading and concentrating, depression, and sleep disturbances. Lead can significantly affect both the reproductive process and the development of the fetus in women with blood lead levels as low as 10 µg/dL. Documented effects include premature birth and low birth weight. In adults, levels as low as 15 µg/dL are linked to increased blood pressure, reduced production of sperm, earlier on-set of menopause, and changes in the enzyme function in the blood.
The increased vulnerability of children results from a combination of factors, including the following:
- The increased susceptibility of the developing nervous system to the neurotoxic effects of lead,
- A higher average rate of soil/dust ingestion among children than among adults,
- The greater efficiency of lead absorption in gastrointestinal tract of children,
- Children's greater prevalence of iron or calcium deficiencies, which may exacerbate absorption and the toxic effects of lead, and
- The ready transfer of lead across the placenta to the developing fetus.
Foods such as fruits, grains, meat, seafood, soft drinks, vegetables and wine may contain lead. Cigarettes also contain small amounts of lead. More than 99% of all drinking water contains less than 0.005 mg/l lead. However, the amount of lead taken into the body through drinking water can be higher in communities with acidic water supplies. Children residing in older dwellings may be exposed to lead by eating lead-based paint chips from peeling surfaces. This is particularly a problem in lower income communities. For occupationally exposed individuals the usual route of exposure is through the inhalation of lead particles.
To determine if individuals were currently being exposed to lead which may have emanated from the site, ATSDR tested the blood of six individuals for lead content. These individuals currently occupy or frequently visits a residence on the street adjacent to the RMI site. One child was found to have an elevated blood lead level. This child was not a full time resident of the house and the source of excess lead exposure in the child could not be determined.
Lead is classified by EPA as a Class B2 probable human carcinogen based on animal studies. This means that there is inadequate evidence to determine lead's carcinogenicity in humans. The estimated exposure doses are 100 or more times lower than the levels shown to cause cancer in animals. Carcinogenic effects are therefore unlikely in the exposed populations.
Toxicological Evaluation Summary
The main public health concern associate with the RMI site is the past exposures to lead. When the facility was in operation, workers were exposed to lead. Biological monitoring of the workers indicates that they were exposed to lead above levels at which adverse health effects could possibly occur. Adverse health effects that could possibly occur in these workers are increased blood pressure, reduced production of sperm, earlier on-set of menopause, and changes in enzyme function in the blood.
Children and pregnant women that resided near the facility when it was in operation were also exposed to lead. Biological monitoring of the children indicate that some of them were exposed to lead above levels at which adverse health effects could possibly occur. Some of the children required medical treatment to reduce the amount of lead in their blood (chelation). Possible effects that maybe caused by elevated lead in the blood include decrease IQ and impaired hearing and growth. In addition, some neurological effects may occur and persist in the exposed children, even through adulthood. The reported symptoms of the neurological effects include poor memory, difficulty reading and concentrating, depression, and sleep disturbances.
However, it is not know if all of the elevated blood lead levels in children can be totally associated to the past exposures from the site/facility. Homes in the vicinity were shown to have lead-based paint. In addition, some of the homes had old cars stored near them. Both of these conditions represent a potential source of lead contamination.
Adverse carcinogenic or non-carcinogenic health effects are not expected to occur because of exposures to antimony and arsenic found in the on-site and off-site surface soils.
ATSDR conducts a review of health outcome data when the toxicological evaluation indicates the likelihood of adverse health outcomes or when the community near the site has health concerns. The evaluation of health outcome data may give a general picture of the health of a community, or it may confirm the presence of excess disease or illness in a community. However, elevated rates of a particular disease may not necessarily be caused by hazardous substances in the environment. Other factors, such as personal habits, socioeconomic status, and occupation, also may influence the development of disease. In contrast, even if elevated rates of disease are not found, a contaminant may still have caused illness or disease.
Based upon data found during ATSDR's site visit in June 1997, former on-site workers were exposed to high concentrations of lead. Many of the workers had elevated blood lead levels in excess of the World Health Organization's blood lead level of concern (20 g/dL). In addition, children residing in the residential community near the site have, in the past, been shown to have elevated blood lead levels.
In May 1998, an exposure investigation was conducted at a house immediately adjacent to the RMI site. To determine if there is current exposure, six members of the household were tested for blood lead content. Environmental samples (surface soil and dust wipe) were also collected. One of the persons tested was shown to have a blood lead level which exceeded the Center for Disease Control and Prevention's blood lead action level of 10 g/dL. This individual does not reside in the residence full time and the actual source of excess lead exposure to this individual could not be determined. The EPA screening level for lead in residential soil is 400 mg/kg. None of the environmental samples taken during the exposure investigation exceeded this level. Off-site environmental soils are not likely to pose a health hazard. Therefore it is unlikely that there is current exposure to contaminants emanating from the RMI site.
Surface soil samples, in the vicinity of the residence where blood lead levels were taken, were analyzed for lead, antimony, and arsenic during the ATSDR exposure investigation. Adverse carcinogenic and non-carcinogenic effects are not expected to occur in potentially exposed individuals.
ATSDR staff attended a public meeting on April 21, 1998 in Rossville, Tennessee. The following concern directly related to the site was expressed during the meeting.
Have residents been affected by heavy run-off from the RMI site created from the soil removal work done by the EPA?
The Environmental Protection Agency has a screening level of 400 mg/kg for lead in soil. The composite soil samples taken from the residential yard closest to the RMI site had a lead level of 217 mg/kg. It is believed that the 217 mg/kg lead level is representative of runoff coming from the site. The level of lead found in the residential yard is far below the screening level that would affect the public health of the residents.
The screening level for arsenic in soil is 0.4 mg/kg. The soil samples taken during ATSDR's exposure investigation had a maximum concentration of 110 mg/kg along the fence on the east side of the site. However, soil samples taken in the residential yard near the site did not contain arsenic at detectable concentrations. Even if a child were to sit right at the fence and play, it is not likely that the duration of exposure and the amount of contaminated soil ingested would be enough to cause non-carcinogenic nor carcinogenic effects.
To ensure that the health of the nation's children is protected, ATSDR has implemented an initiative to protect children from exposure to hazardous substances, because children can be uniquely vulnerable to environmental toxicants, depending on the substance and the exposure situation. Infants and children are usually more susceptible to toxic substances than adults due to immature and developing organs. Activities associated with playing close to the ground may increase their exposure to toxicants in dust, soil, and airborne particulate matter. Children also exhibit hand to mouth behavior, which may increase their intake of toxicants. ATSDR's evaluation contained within this document considered children as a susceptible subpopulation and found on-site and off-site surface soil as completed environmental exposure pathways for them.
Lead presents a significant health hazard in children and presents a difference in the pharmacodynamic and pharmacokinetic parameters for adults and children. Lead exposure is hazardous for unborn children and young children because they are more sensitive to lead during development. Unborn children can be exposed to lead via transplacental migration. Such exposures could cause premature births, smaller babies, and a decrease in mental ability.
Children are more likely to experience lead-induced adverse health effects. Children absorb lead through the GI tract more readily than adults. They also have immature detoxification enzyme systems which leads to an increase body burden of lead once ingested. Children have lower thresholds for neurological and hematological adverse effects from lead exposure.
In studies of chronic exposure, children appear to be more severely affected by arsenic than adults, probably due to higher exposure per body weight (body burden). Unborn children can be exposed via transplacental migration. Neural tube defects are the most predominant and consistent malformations in mammalian species tested. The association between prenatal arsenic exposure and congenital malformations has not been fully established, but in light of arsenic's teratogenic potential in other mammalian species, humans are likely to be sensitive to these effects.
- Based upon data reviewed and observations made, the Ross Metals, Inc. National Priorities List site is currently categorized by the Agency for Toxic Substances and Disease Registry (ATSDR) as a Public Health Hazard, because physical hazards exists on-site.
- ATSDR currently considers the residential area adjacent to the site to be a No Apparent Public Health Hazard. The time-critical removal conducted by the U.S. Environmental Protection Agency (EPA) has removed the lead contamination that formerly was in the residential area next to the site and has minimized the potential for on-site contaminants to migrate into the residential area. In addition, the results of the environmental sampling conducted during the ATSDR exposure investigation did not find any lead or arsenic surface soil contamination in the residential area at levels of health concern. The blood lead levels of adults and children that currently reside next to the site are also below the current action levels recommended by the CDC.
- In the past, workers at the facility, while it was in operation, and residents near the site were exposed to lead at levels of health concern. Therefore, both the RMI site and the residential area adjacent to the site are considered as a Public Health Hazard in the past. Previous investigations have documented that workers and children near the facility had elevated blood lead levels above the Centers for Disease Control and Prevention (CDC) action levels. Possible adverse health effects that could possibly occur in the workers are increased blood pressure, reduced production of sperm, earlier on-set of menopause, and changes in enzyme function in the blood. Possible effects that may be caused by elevated blood lead in children include decreased IQ and impaired hearing and growth. In addition, some neurological effects may occur and persist in the exposed children, even through adulthood. The possible symptoms of the neurological effects include poor memory, difficulty reading and concentrating, depression, and sleep disturbances.
Cease/Reduce Exposure Recommendations
- Continue to restrict all public access to the site and contaminated areas until contamination is remediated.
- Remediation of the on-site contamination and physical hazards should be conducted.
- Ensure that shallow wells are not constructed in the area of the site to reduce possible exposure to contaminated groundwater.
- Maintain safeguards to ensure that migration of fugitive dusts from slag piles are reduced.
Site/Area Characterization Recommendations
None at this time.
The Public Health Recommendations and Action Plan (PHRAP) for the Ross Metals, Inc. National Priorities List site contains a description of action taken, to be taken, or under consideration by ATSDR and/or other government agencies in the vicinity of the site subsequent to the completion of this public health assessment. The purpose of the PHRAP is to ensure that this public health assessment not only identifies public health hazards, but provides a plan of action designed to mitigate and prevent adverse human health effects resulting from exposure to hazardous substances in the environment.
- ATSDR has visited the RMI site in order to verify site conditions and to gather pertinent information and data for the site.
- ATSDR has met with local citizens to determine their concerns regarding the RMI site.
- ATSDR has conducted an exposure investigation in order to address community concerns regarding possible contamination originating from the RMI site. The results of the exposure investigation have been made known to the participants.
- ATSDR will continue to collaborate with the appropriate federal, state, and local agencies to pursue the implementation of the recommendations outlined in this public health assessment.
- ATSDR will continue to review any new environmental and health outcome data associated with the Ross Metals, Inc. National Priorities List site and if necessary, revise the conclusions and recommendations contained in this public health assessment.
Environmental Health Scientist
Superfund Site Assessment Branch
Division of Health Assessment and Consultation
Déborah A. Boling
Superfund Site Assessment Branch
Division of Health Assessment and Consultation
Community Involvement Specialist
Community Involvement Activity
Division of Health Assessment and Consultation
Health Education Specialist
Division of Health Education and Promotion
Public Health Advisor
Office of Regional Operations
- U.S. Environmental Protection Agency, Region IV, Atlanta, Georgia. Hazard ranking system documentation record, Ross Metals, Inc., 1996.
- EPA. Summary data package covering 1990 RCRA investigations, 1994-1995 Superfund time-critical removal, 1995 preremedial investigation, and 1996 Superfund remedial site characterization. Atlanta: EPA, Region IV, 1997.
- Lake Engineering, Incorporated. 1988. RCRA Part B Permit Application, prepared for Ross Metals, Inc. Rossville, Tennessee.
- Tobin, Patrick M. Memorandum to Mr. Steve Ross, Vice-President, Ross Metals, Incorporated. September 4, 1990. Subject: Complaint and Compliance Order. Atlanta: EPA, Region IV.
- Agency for Toxic Substances and Disease Registry. Records of Activity concerning the Ross Metals site. Atlanta: ATSDR Region IV Office, May 1995.
- EPA Environmental Services Division. RCRA case development investigation/evaluation, Ross Metals, Rossville, Tennessee. Atlanta: EPA Region IV, November 1990. ESD Project No. 91-197.
- EPA. Chemical Releases and Their Chemical Risks. A Citizen's Guide to Risk Screening. Washington, D.C.: U.S. Environmental Protection Agency (EPA). 1989.
- EPA. Toxic Chemical Release Inventory. Washington, D.C.; National Library of Medicine, 1987-1991.
- Agency for Toxic Substances and Disease Registry. Public health assessment guidance manual. Atlanta: ATSDR, March 1992; DHHS, (PHS).
- EPA. Exposure Factors Handbook. Washington, DC: Environmental Protection Agency, Office of Health and Environmental Assessment, July 1989, EPA Document No. 600/8-89/043.
- Agency for Toxic Substances and Disease Registry. Toxicological profile for antimony. Atlanta: ATSDR, September 1992; DHHS publication no. (PHS)TP-91/02.
- Shacklette, HT, JG Boerngen. Element concentrations in soils and other surficial material of the conterminous United States. U.S. Geological Survey Professional Paper 1270. Washington, DC: U.S. Government Printing Office, 1984.
- Ainsworth, N. Distribution and biological effects of antimony in contaminated grassland. Dissertation. 1988.
- Agency for Toxic Substances and Disease Registry. Toxicological profile for arsenic. (update) Atlanta: ATSDR, August 1998.
- Agency for Toxic Substances and Disease Registry. Toxicological profile for lead. (update) Atlanta: ATSDR, August 1997; DHHS publication.