PUBLIC HEALTH ASSESSMENT
KOPPERS COMPANY INC./FLORENCE PLANT
FLORENCE, FLORENCE COUNTY, SOUTH CAROLINA
The tables in this section list the contaminants of concern. We evaluate these contaminants inthe subsequent sections of the public health assessment and determine whether exposure to themhas public health significance. This public health assessment selects and discusses thesecontaminants based upon the following factors:
- Concentrations of contaminants on and off the site.
- Field data quality, laboratory data quality, and sample design.
- Comparison of on-site and off-site concentrations with background concentrations, if available.
- Comparison of on-site and off-site concentrations with public health assessment comparison values for (1) noncarinogenic endpoints and (2) carcinogenic endpoints.
- Community health concerns.
In the data tables that follow under the On-site Contamination and the Off-site Contaminationsubsections, the listed contaminant does not mean that it will cause adverse health effects fromexposures. Instead, the list indicates which contaminants will be evaluated further in this PublicHealth Assessment. When selected as a contaminant of concern in one medium, thatcontaminant will be reported in all media.
|= Cancer Risk Evaluation Guide|
|= Environmental Media Evaluation Guide|
|= Reference Dose Evaluation Guide|
|= EPA Maximum Contaminant Level Goal|
|= EPA Maximum Contaminant Level|
|= EPA Proposed MCLG|
|= EPA Proposed MCL|
|= EPA Reference Dose|
|= EPA Lifetime Health Advisory|
|= Parts Per Million|
|= Parts Per Billion|
Comparison values for public health assessment are contaminant concentrations in specificmedia that are used to select contaminants form further evaluation. These values includeEMEGs, CREGs, and other relevant guidelines. CREGs are estimated contaminantconcentrations based on a one excess cancer in a million persons exposed over a lifetime. CREGs are calculated from EPA's cancer slope factors. EPA's MCLG is a drinking water healthgoal. EPA believes that the MCLG represents a level that no known or anticipated adverseeffect on the health of persons should occur which allows an adequate margin of safety. PMCLGs are MCLGs that are being proposed. MCLs represent contaminant concentration thatEPA deems protective of public health (considering the availability and economics of watertreatment technology) over a lifetime (70 years) at an exposure rate of 2 liter water per day. While MCLs are regulatory concentrations, PMCLGs and MCLGs are not. EPA's RfD is anestimate of the daily exposure to a contaminant that is unlikely to cause adverse health effects.
All data in the On-Site and Off-Site Contamination sections are derived from the December1990 RCRA RFI, unless otherwise noted.
Toxic Chemical Release Inventory Data (TRI)
Project Staff conducted a search of EPA's Toxic Chemical Release Inventory (TRI) for the years1988 and 1989. The search included a 2-mile radius from the site. TRI recorded sevencompounds for KII-F: anthracene, dibenzofuran, naphthalene, pentachlorophenol, phosphoricacid, arsenic, chromium, and copper. TRI lists the disposal for many of these compounds toTwo Mile Creek by stormwater run-off.
The RFI reports sampling of on-site groundwater in August, November, and December of 1989. In August 1989, groundwater samples were collected from all existing on-site and off-sitemonitoring wells and all recovery wells. The Keystone laboratory analyzed these samples fortotal arsenic, dissolved arsenic, total chromium, dissolved chromium, hexavalent chromium,total mercury, dissolved mercury, volatile aromatic compounds, acid extractable phenolics, totalphenols, and polycyclic aromatic hydrocarbons (PAHs) (19).
Seven monitoring wells were installed in September 1989. In November 1989, the monitoringwells and selected other wells were sampled for the same compounds as in August and forcopper and mercury. In December 1989, the RFI re-sampled four on-site shallow wells in orderto confirm previous testing (19).
These three RFI sampling rounds were evaluated and are presented in this Public HealthAssessment. All groundwater samples were collected by Keystone Environmentalrepresentatives and analyzed by Keystone's Analytical Division. Table 2 summarizes the rangeof chemical concentrations detected in these sampling rounds.
|Contaminant||Groundwater Zone (ppb)||Recovery|
|A and B||C and D|
|Polycyclic Aromatic Hydrocarbons||455,000||626||5,670,000||No Value|
|Dissolved Chromium||10||ND||ND||100 MCL|
|Hexavalent Chromium||41.4||0.012||20||50 EMEG|
|Dissolved Copper||25.5||ND||1,300 MCL|
|Dissolved Mercury||3.1||ND||3.61||2 MCL|
|Dioxins and Furans **||0.00166|
** - Dioxin and Furan results are from a sample of six on-site monitoring wells.
Soil boring samples were collected from twelve Solid Waste Management Units (SWMUs) inAugust and September 1989. These samples were collected at two feet intervals from areas thatwere most likely to be contaminated (the closed creosote lagoon, the abandoned landfill, the driptrack area, the former spray-field, the existing spray-field, and the former pentachlorophenolpond) (19). The samples were not representative of surface soil samples. ATSDR definessurface soil as soil from 0" to 3" in depth. Surface soil samples are needed for the evaluation ofpublic health impact associated with exposures to contaminants in this media. In the absence ofthis data, chemical data for deeper soils may suggest the possibility of human exposure and thedevelopment of toxicity. This method, however, only provides a tentative evaluation. A"background" soil sample was collected from near the plant office and was designated to be abackground sample; however, this sample may not be representative of a true background sample.
Visual contamination guided the selection of soil samples. The Keystone Environmental Divisionlaboratory performed the analyses including pH, total recoverable phenols, acid extractablephenolics, oil and grease, PAHs, arsenic, copper, chromium, and mercury. Selected samples werealso analyzed for hexavalent chromium, and dioxins and furans (19).
The highest levels of carcinogenic PAHs were found in the old creosote lagoon. Table 3 presents the contaminants of concern identified for this media.
|Contaminant||Concentration Range-ppm||Comparison Value-ppm|
|Pentachlorophenol||ND - 2,230||No Value|
|2,3,5,6-Tetrachlorophenol||ND - 332||No Value|
|2,4,6-Trichlorophenol||ND - 101||No Value|
|2,4-Dichlorophenol||ND - 68.8||No Value|
|2,4-Dimethylphenol||ND - 27.6||No Value|
|2-Chlorophenol||ND - 38.2||No Value|
|2-Methyl-4,6-Dinitrophenol||ND - 308||No Value|
|2,4-Dinitrophenol||ND - 309||No Value|
|4-Chloro-3-Methylphenol||ND - 185||No Value|
|4-Nitrophenol||ND - 341||No Value|
|2-Nitrophenol||ND - 74.3||No Value|
|Phenol||ND - 18.6||No Value|
|Polycyclic Aromatic Hydrocarbons|
|ND - 13,600||No Value|
|Arsenic||ND - 152||2 EMEG|
|Chromium||ND - 326||10 EMEG|
|Copper||ND - 38.1||No Value|
|Mercury||ND - 29.9||No Value|
|Dioxins and Furans **||0.00000146 - 0.004155||0.000002 EMEG|
** - Dioxins and Furans are assessed in terms of Toxicity Equivalents (TEQs). The TEQs listed here are from the RFI report.
On-site air monitoring was conducted on September 12, 13, and 14, 1989 as part of theinvestigations for the RFI. One upwind and two downwind sampling locations varied based onthe wind direction. Sampling times were chosen to minimize the influence of emissions fromregulated units on the KII-F property. On all three days, one of the sampling locations waslocated near the southwestern corner of the site. Depending on the wind direction, this locationwas either an upwind or downwind sampling station. Samples from this location showed eitherthe highest or near the highest concentrations of PAHs and pentachlorophenol detected on-site. Table 4 presents the contaminants of concern identified for this media.
(micrograms / standard cubic meter)
|Arsenic||0.002 - 0.017||10 EMEG|
|Copper||0.014 - 0.14||No Value|
|Chromium||0.006 - 0.31||No Value|
|Pentachlorophenol||ND - 0.24||No Value|
|Polycyclic Aromatic Hydrocarbons||ND - 980||No Value|
Groundwater - Monitoring Wells
According to a January 6, 1989 memorandum from Gary Stowe, SCDHEC Pee Dee District,district personnel made a composite sample of four Florence wells on February 15, 1988. TheSCDHEC laboratory analyzed this sample for 59 compounds including various chlorinatedaliphatic (non-aromatic) compounds, benzene, dichlorobenzenes, chlorotoluenes, naphthalene,and xylenes. The analysis did not show the presence of any of these compounds.
On June 11, 1991, Representatives of Keystone Environmental Resources sampled eightresidential wells in the Hyman street Neighborhood. Sampling analysis did not reveal thepresence of either or phenolic compounds. Table 5 summarizes the results of off-site monitoringwell sampling for the RFI.
Groundwater - Private Wells
In February 1992, representatives of SCDHEC and EPA Region IV performed a door-to-doorwell survey of the areas to the southeast, south, and southwest of the KII-F site. This surveyincluded the Day Street and Mustang Drive neighborhoods. On March 3, 1992, EPA Region IVEnvironmental Services Division collected water samples from several private wells identified bythe February 1992 survey. No contaminants of concern were detected in these wells.
No off-site soil data are available for review. This pathway will be evaluated as data becomes available.
Surface Water and Sediment
Surface water was sampled from the tributaries located east and south of the site in August andNovember 1986 and in May 1987. ATSDR and the EPA currently do not have comparisonvalues that are appropriate for accessing contaminants detected in surface water, sediments, andfish tissue. Table 6 presents the concentration range of the contaminants detected in these media;these contaminants will be evaluated further in this public health assessment.
The RFI conducted two additional rounds of surface water and sediment sampling in August andDecember of 1989. Table 7 presents the contaminants of concern identified in these media.
|Contaminant||Groundwater Zone (ppb)||Comparison|
|A and B||C and D|
|Polycyclic Aromatic Hydrocarbons||55,100||11.2||No Value|
|Dissolved Arsenic||20||ND||0.000006 CREG|
|Dissolved Mercury||2.28||1.58||2 MCL|
|Contaminant||Surface Water **|
|Fish Tissue ****|
|Arsenic||ND - 58||ND - 8.59||0.28 - 17|
|Chromium||ND - 206||ND - 45.4||ND - 1.52|
|Copper||ND - 65||ND - 33.8||ND - 9.52|
|Oil and Grease||ND - 21,400||ND - 1,000|
|Pentachlorophenol||ND - 840||ND - 14.6||0.38 - 32.2|
|Phenolic Compounds||ND - 48||ND - 1.2||1.38 (1 sample)|
|Naphthalene||ND - 5||ND - 21.1||ND - 0.33|
|Polycyclic Aromatic Hydrocarbons||ND - 129||ND - 318.8||ND - 0.71|
** - Surface water samples were drawn in August 1986, November 1986, February1987, and May 1987.
*** - Sediment samples were taken in August 1986 and February 1987.
**** - Fish samples were taken November 1986, May 1987.
|Contaminant||Surface Water (ppb)||Sediments (ppm)|
|Pentachlorophenol||ND - 248||ND - 3.32|
|2,3,5,6-Tetrachlorophenol||ND - 12.9||ND - 1.74|
|2,4,6-Trichlorophenol||ND - 1.56||ND - 4.36|
|2,4-Dichlorophenol||ND - 6.04||ND - 2.27|
|2,4-Dimethylphenol||ND||ND - 0.157|
|2,4-Dinitrophenol||ND - 3.62||ND - 3.74|
|2-Methyl-4,6-dinitrophenol||ND - 5.94||ND - 3.13|
|4-Chloro-3-methylphenol||ND||ND - 0.125|
|4-Nitrophenol||ND||ND - 1/17|
|2-Nitrophenol||ND - 1.92||ND - 0.274|
|Polycyclic Aromatic Hydrocarbons||ND - 67.664||ND - 58.6|
|Dioxins and Furans||0.0000102 -0.003729||0.0000129 -0.002643|
|Arsenic||ND - 93.8||ND - 18.6|
|Dissolved Arsenic||ND - 13.1|
|Chromium||ND - 160||ND - 46.5|
|Copper||ND - 118||ND - 26.9|
|Mercury||ND||ND - 5.23|
In August and December 1989, the RFI sampled the biologic diversity of fish and benthicorganisms at the same locations as those sampled for surface water and sediments. This surveyindicated environmental/toxic stress in the biota of tributaries east and south of the site. Theamount of stress decreases as the distance from the site increases. The creek to the east of thesite has been impacted to a greater degree than the creek to the south of the site.Environmental/toxic stress is not a direct measure of human health; however, it may be related toseveral factors that are or are not associated to the site. It also suggests the possibility that fishand other foods from these creeks may be contaminated (19).
Crayfish tails were analyzed for arsenic, chromium, copper, mercury, PAHs, acid extractablephenolic compounds, and total recoverable phenolic compounds. Not enough crayfish werecollected for analysis with the exception of one station located beyond the Old Mars BluffNeighborhood (FS-13). Fifty-three crayfish tails were combined into one sample (19). Table 6presents the contaminants of concern identified for this media.
The data in this section are from the 1990 RCRA RFI. Thus, this report contains the latestinformation for this site. Quality Assurance and Quality Control (QA/QC) conclusions drawn forthis public health assessment are determined by the validity of the analysis and conclusions madeand the availability and reliability of the referenced information. SCDHEC assumes that adequatequality assurance and quality control measures were followed with regard to chain-of-custody,laboratory procedures, and data reporting.
The data analyses of groundwater were performed by Keystone Environmental Resources, Inc. Keystone Environmental Resources, Inc. is certified by the State of South Carolina to conductsuch analyses. Full Quality Assurance and Quality Control data were not supplied within theRFI. The RFI states that organic compound identification was on the basis of retention data only. The use of retention data could result in misidentification of compounds.
According to information supplied by Keystone Environmental Resources, Inc., approximatelyhalf of the volume of creosote is composed of 25 to 30 compounds. Of these, only a dozen arelisted as priority pollutants by the EPA. Creosote is a mixture of many chemicals. Analysesperformed would include less than half of the material present in creosote and only a small numberof the possible compounds. This reflects the scientific uncertainty associated with this mixture.
Groundwater data sheets often report an unrealistically high number of significant figures, e.g.-total PAHs of 4366.705 µg/L. In some samples, concentrations of dissolved metals were higherthan the concentrations of total metals, and concentrations of hexavalent chromium were higherthan total chromium.
The RFI did not collect surface soil samples. ATSDR defines surface soil as soil from 0" - 3" indepth. Surface soil samples are needed to evaluate the public health impact that contaminantsfound in this media could pose. In the absence of this data, chemical data for deeper soils maysuggest the possibility of human exposure and the development of toxicity. This method,however, only provides a tentative evaluation.
A "background" soil sample was collected from a location between the plant office and the woodtreatment area. The concentrations of arsenic, chromium, and copper detected in this samplewere comparable to other samples in the eastern United States. The concentration of mercury inthe "background" soil sample is approximately ten times the mean concentration of mercury in theeastern United States but within the observed range (ATSDR Public Health AssessmentGuidance, February 1991). The presence of chlorinated phenols in this sample indicate that plantactivities may have led to contamination of this location.
Available air data was collected at the same time on three consecutive days. The wind conditionson the collection dates was an approximate 6 miles per hour. Higher winds would be more likelyto entrain soil particles that could lead to exposures. While these data may suggest thecomposition and concentration of contaminants, the lack of variation in sampling time, the briefperiod of time, and the lack of variation in weather conditions prevent any firm conclusionsrelative to air contamination.
The analysis of crayfish tails was derived exclusively from station FS-13. This station is locatedsouth of the site. Additional monitoring of fish and crayfish is necessary to accurately evaluatethe site's potential impact on food-chain entities. Because of the unavailability of specimens, fishtissue analyses represent only a few of the specified sampling locations.
KII-F is an active wood-treatment plant. Physical hazards include industrial machinery, stacked lumber, and a railroad yard.
To determine whether nearby residents may be affected by contaminants at the site, ATSDR andSCDHEC evaluate the environmental and human components that lead to human exposure. Thispathways analysis consists of five elements: a source of contaminations; transport through anenvironmental media; a point of exposure; a route of human exposure; and an exposed population.
ATSDR and SCDHEC identify exposure pathways as completed, potential, or eliminated. Completed pathways have all five elements and indicate that exposure to a contaminant hasoccurred in the past, is currently occurring, or will occur in the future. Potential pathways,however, have at least one of the five elements missing, but could exist. Potential pathwaysindicate that exposure to a contaminant could have occurred in the past, could be occurring now,or could occur in the future. Eliminated pathways have at least one of the five elements missingand will never be present. Completed and potential pathways may be eliminated when they areunlikely to be significant. The discussion which follows identifies the completed, potential, andeliminated pathways at this site.
Regional Geology and Hydrogeology
There are three major aquifers beneath the KII-F site: the Shallow Aquifer system, the BlackCreek Aquifer, and the Middendorf Aquifer. Groundwater from these aquifers supplies water forthe city of Florence. Two of the ten water supply wells for the City of Florence are located lessthan one mile downgradient and to the southwest of the sit e; both of these wells draw water fromthe Middendorf aquifer. The water table at the site is usually approximately ten feet below theground surface. Shallow groundwater is generally slightly acid; most pH values measured frommonitoring wells range between 4.5 and 6.0
Monitoring wells are screened into A(10-foot), B(50-foot), C(100-foot) and D(deeper than 100-foot) monitoring zones. The A and B zones appear to be connected and be in the upper portionof the Shallow Aquifer. The C zone is the lower portion of the Shallow Aquifer and the D zone iswithin the Black Creek Aquifer. Groundwater in the A and B zones flows to the southwest in thewestern portion of the site and to the southeast in the eastern portion of the site. The C and Dzones flow toward the west.
A confining unit appears to separate units A and B from the deeper units (C and D). However,the site consists of a downward gradient that may serve to spread contaminants to the deeperaquifers. Low levels of contaminants have been detected in wells screened in the C and D zones.
|Exposure Pathway Elements||Time|
A past completed exposure pathway has been identified for the KII-F site. Residents of the DayStreet neighborhood complained of creosote odors emanating from their private drinking waterwells. SCDHEC tested these wells and found phenolic compounds in the water. KII-F paid formunicipal water lines to be installed and for the water bills for these residences for one year. However, not all residents agreed to use this water supply. Records do not indicate if the watersupply wells were removed from use. Because of economics, many residents who were utilizingmunicipal water may have reverted to the use of wells. Project staff have noted well houses inthis neighborhood.
The 1988 Preliminary Health Assessment noted deficiencies in the groundwater data from theprivate wells in the vicinity of KII-F. In February and March 1992, EPA sampled private wellsidentified in areas southeast, south, and southwest of the site. These wells did not show thepresence of site-related contaminants. Therefore, this pathway is not considered to be of concernat this time.
KII-F has operated a series of 14 extraction wells downgradient of the site for the last four years. If effective, these wells should prevent the migration of contaminated on-site groundwater tothese neighborhoods.
|Exposure Pathway Elements||Time|
Future potential exposure pathways have been identified for the Old Mars Bluff, the MustangDrive, and the Day Street neighborhoods. A SCDHEC survey of the Old Mars Bluffneighborhood revealed the presence of well houses in most yards. Wells from this neighborhoodhave not been sampled. Therefore, this pathway cannot be evaluated at this time.
Hydrogeologic data indicates the possible migration of contaminated groundwater toward theMustang Drive neighborhood. Sampling data show only small concentrations of contaminants inthis direction. In March 1992, EPA sampled a private well in this neighborhood; no site-relatedcontaminants were detected.
A past completed exposure pathway was identified for the Day Street neighborhood. Samplescollected and analyzed in February and March 1992 did not detect site-related contaminants;therefore, no exposures are known to be occurring at this time. A series of 14 extraction wellsare operable in this area and if effective, are believed to prevent the migration of on-sitegroundwater contamination from spreading to these neighborhoods. However, if the extractionwell system is not fully effective, it is possible that contaminated groundwater could migratetowards the identified private wells.
In February and March 1992, EPA sampled private wells identified in areas southeast, south, andsouthwest of the site. These wells did not show the presence of site-related contaminants. However, because of the low concentrations of contaminants in multiple wells between KII-F andthese neighborhoods, there could be a potential exposure pathway if people decide to utilizecontaminated groundwater as their drinking water source.
Because of the sandy nature of the soil on the site and the proximity of SWMUs to populatedareas, it appears reasonable to assume that contaminated soils could be spread to the nearbyneighborhoods. However, because of the lack of surface soil data, this is considered a potentialpathway. Exposures could also occur if trespassers accidentally ingest or come into dermalcontact with contaminated soil.
Soil contamination on the site is due to landfilling and to the release of contaminants. Contaminated soil could be stirred by wind and nearby residents, on-site workers, or trespasserscould accidentally ingest the soil. The average adult ingests small amounts of soil; children tendto ingest larger amounts of soil because of their patterns of hand to mouth contact.
Surface soil samples are needed to better characterize the extent of soil contamination. Analysisof these samples are needed to provide information for the evaluation of adverse human healtheffects associated with exposures to specific contaminant levels.
Surface Water and Sediment Pathway
A potential exposure pathway has been identified for surface water and sediments. Surface waterrunoff from the site has led to documented contamination to the streams located to the south andeast of the site. Exposures could occur to people who ingest or come into dermal contact withcontaminated surface water or sediments. However, the streams are very small and it is unlikelythey would be used as primary drinking water sources. Therefore, this pathway is not consideredto be of concern at this time.
These two streams lead to nearby rivers. These streams consist of ditches and narrow (two-footwide) creeks with little observable flow except in periods of heavy rain on the site. The beginningof Two Mile Creek leads northeastwardly toward Polk Swamp. Polk Swamp leads toward thesouth. An unnamed tributary stems from the western portion of the site toward Jeffries Creek. This tributary crosses the Day Street neighborhood and the Old Mars Bluff neighborhood.
Data indicate contamination of fish and crayfish in the streams near the site. However, because ofthe difficulties in obtaining an adequate sample, this contamination has not been fullycharacterized. Project staff have observed people fishing in these creeks; therefore this isconsidered a potential exposure pathway. Because of the size of these streams, sustenance fishingappears unlikely. However, it is possible that a person may occasionally ingest fish from thisstream. Additional data are needed to better characterize and evaluate the potential for adversehealth effects associated with the ingestion of contaminated fish and crayfish. The South CarolinaWildlife and Marine Resources Department reports that Jeffries Creek is a major fishery for theFlorence area. (The stream southwest of the site flows into Jeffries Creek.) However, neithersite-specific creel surveys nor angler effort statistics are available.
Air monitoring showed very low levels of contaminants. These contaminants could be due to thecontinued operation of the plant or they could represent either the volatilization of contaminantsfrom soil and the entrainment of contaminated soils by wind. The contaminated air could beinhaled.
Although the monitoring was not sufficient for drawing a firm conclusion, the monitored levels ofcontaminants were very low. The expected doses would be much less than the doses anticipatedfrom other routes of exposure.
In this section we will discuss the health effects which may impact on people exposed to site-related contaminants. To evaluate health effects which may result from an exposure, ATSDR hasdeveloped Minimal Risk Levels (MRLs). MRLs estimate an exposure which is not likely to causedeleterious health effects; exposure to even lower amounts would be even less likely to causeadverse health effects. MRLs are specific to the route of exposure and the length of exposure. Routes of exposure may include ingestion (eating and drinking), inhalation (breathing), anddermal absorption (absorption through the skin). The duration of exposure is commonly classifiedas acute (less than 14 days), intermediate (15 to 364 days), and chronic (greater than 365 days)exposures.
ATSDR developed MRLs to assess the possible toxicity of compounds to body organs. MRLs donot include information on the potential of compounds to cause cancer. In general, we assumethat a person exposed to small amounts of a carcinogenic compound will incur a small increase inthe statistical probability of developing cancer. A person exposed to larger doses of thecompound will incur a larger increase in the statistical probability of developing cancer.
This Public Health Assessment expresses the additional probability of developing cancer as aresult of an exposure to a chemical in terms of no increased risk, no apparent increased risk, a lowincreased risk, a moderate increased risk, and a high increased risk. EPA has developed amathematical methodology for estimating the extreme maximum probability that a person willdevelop cancer as a result of exposure to a chemical. The EPA Risk expresses estimates in thecorresponding terms of less than one-in-a-million risk, one-in-one-hundred-thousand risk, one-in-ten-thousand risk, one-in-one-thousand risk, and one-in-one-hundred risk.
ATSDR also develops Toxicological Profiles on chemical contaminants commonly found athazardous waste sites. These documents provide information on health effects, environmentaltransport, human exposure, and regulations affecting these substances.
The human exposure pathways section of this Public Health Assessment lists the routes by whichsite-related contaminants may enter the human body. As stated above, an evaluation of thesehazards relies on an accurate estimation of the amount of these chemicals to which a person maybe exposed. This estimate will use several standardized assumptions.
We will assume that an adult weighs 70 kilograms (154 pounds) and a child weighs 10 kilograms(27 pounds). An adult ingests 2 liters of water per day (2 L/day, the same as a 2-liter sodabottle). A child drinks half that amount (1 l/day). During the course of the day, adults typicallyingest 50 to 100 milligrams of soil per day (mg/day); this occurs by both inhaling small soilparticles carried in the air and by placing soiled hands and other objects in the mouth. Becausesmall children typically place objects in their mouths, it is assumed that they ingest a greateramount of soil, typically 200 mg/day.
The following discussions of chemicals rely on the preceding assumptions combined with theinformation in the Exposure Pathways section.
Polycyclic Aromatic Hydrocarbons (PAHs)
The ATSDR Toxicological Profile for PAHs states that PAHs are a group of chemicals that areformed by the incomplete burning of coal, oil, gas, garbage, tobacco, or almost any other organicsubstance. Natural sources of PAHs include forest fires and volcanoes. Consequently, PAHsoccur throughout the environment in the air, water, and soil.According to the toxicological profile, the only significant health effect demonstrated in humansfollowing low-level exposure to some PAHs is cancer. Although animal studies have suggestedthat other effects may occur, these have not been adequately documented. Because only a fewPAHs have been shown to cause cancer in laboratory animals, this public health assessmentdivides PAHs into carcinogenic (cPAHs) and non-carcinogenic PAHs (15).
The most likely route of exposure to cPAHs could be from ingestion of off-site groundwater. This dose is several orders of magnitude greater than the doses that could be received from theinhalation of on-site air, the ingestion of on-site soil, and the ingestion of off-site fish.
EPA is currently reassessing the toxicologic data for PAHs. However, an idea of their potencymay be derived from the information within the July 25, 1990 Federal Register. Using this data,the ingestion of maximally contaminated off-site groundwater for a lifetime could lead to a veryhigh increased risk of developing cancer. Additionally, on-site groundwater concentrations aregreater than off-site concentrations. If the amount of off-site contamination should increase, ahigher carcinogenic risk would result.
Off-site soil has not been tested, and there are no surface soil samples for evaluation. Because ofthese data limitations, on-site subsurface soil may serve as a representation of an extreme worstcase. It appears unlikely that any person could chronically contact on-site subsurface soil. In thiscase, the ingestion of on-site soil could add a high increased risk of developing cancer. Thisestimate will be revised as further information becomes available.
Because of the small number of fish found in the associated creeks and the resulting improbabilityof a regular, lifetime exposure, the cancer risk from eating fish tissue will not be further considered under PAHs.
ATSDR has developed an acute MRL for PAHs (15). The ingestion of maximally contaminatedoff-site groundwater would result in a dose which is thirty times the ATSDR acute MRL. However, the MRL is 100 times below the No Observed Adverse Effect Level (NOAEL) inanimals. The NOAEL was the dose in a particular animal study at which no adverse health effectswere observed. This study looked at the development of adverse reproductive effects, which is avery sensitive predictor of a chemical's toxicity. In developing the MRL, ATSDR used safetyfactors because the information was not based upon a study involving humans, and for variabilitybetween humans. Based upon this animal study, health effects in humans would not beanticipated from acute exposures to the levels found in the groundwater. However, some humansare more susceptible to the effects of PAHs due to sensitivity to PAHs, having other sources ofexposure to PAHs, or a compromised immune system. These individuals may be at risk ofdeveloping adverse health effects from exposure to maximally contaminated off-site groundwater.
ATSDR has not developed chronic or intermediate oral MRLs for PAHs. Other than cancer, theintermediate health effects listed in the ATSDR Toxicological Profile occur at doses similar to theacute effects. The ATSDR Toxicological Profile does not list adequate studies for thedetermination of chronic health effects following oral exposure. The EPA Integrated RiskInformation System Database (IRIS) does not list an oral Reference Dose (RfD) for PAHs.
The ATSDR Toxicological Profile for Pentachlorophenol states that this chemical was one of themost extensively used pesticides in the United States. It is still used extensively as a woodpreservative (13).
According to the toxicological profile, the ingestion and dermal contact of PCP may be followedby toxicity to the liver, kidney, blood, nervous system, and gastrointestinal tract according to thetoxicological profile. Animal studies have shown that PCP is also toxic to the immune system andto the fetus (13).
The ingestion of water from PCP-contaminated groundwater in the Day Street neighborhoodcould be of concern at this site. However, PCP was not present in 1992 private well samples. Therefore, ingestion of PCP contaminated water is not occurring at the present time and noadverse health effects are expected. If contaminated groundwater is not remediated, it is possiblethat the future migration of groundwater could lead to human exposures. Off-site monitoringwells in the direction of the Day Street neighborhood display PCP concentrations up to 6,370µg/L. Children ingesting this water would receive a PCP dose slightly greater than equivalentdoses causing toxicity to the immune system in rats. Additionally, this dose is one-fortieth thelethal acute dose in rats. Therefore, the ingestion of this contaminated water by humans maycause the health effects listed in the preceding paragraphs. The EPA has proposed a limit(Maximum Contaminant Level) of 1 µg/L of PCP in drinking water.
Numerous studies show that PCP is absorbed through the skin and that it evaporates easily. Using this water for household uses would increase the dose of PCP and the probability ofdeveloping health effects similar to those of ingesting the water.
According to the toxicological profile, laboratory animals exposed to high levels of PCP havedeveloped an increased rate of cancer. Although there is no conclusive evidence that PCP causescancer in humans, the EPA treats PCP as if it may cause cancer in humans (13). The extremelyhigh concentration of PCP in monitoring wells would lead to a very highly significant risk ofdeveloping cancer as a result of drinking this water over a lifetime.
A person ingesting on-site soil would receive a dose of PCP just slightly above the ATSDR MRL(13) for an intermediate duration of exposure. The dose received from inhaling on-site air isnegligible. As a trespasser would only be exposed to on-site soil for brief periods of time andneither on-site nor off-site surface soil data are available, an estimate of carcinogenic potency willnot be made at this time. However, the health effects resulting from exposure to PCP are due tothe total exposure. That is, one must add the doses received from ingestion, inhalation, anddermal exposure.
Polychlorinated Dioxins and Furans
Polychlorinated dioxins and polychlorinated furans have similar chemical and toxicologicproperties. This report will refer to these compounds as dioxins.
Dioxins are inadvertently produced in very small amounts as an impurity during the manufactureof other chemicals, including certain wood preservatives. Further information on the chemicalproperties, physical properties, and general toxicology of dioxins may be found in the ATSDRToxicological Profile for 2,3,7,8-Tetrachloro-Dibenzo-p-Dioxin (9).
In humans, doses of dioxins greater than those anticipated from the ingestion of site-relatedgroundwater or soil may cause chloracne. (Chloracne is an eruption on the skin similar to acnethat results from exposure to chlorine and its compounds). Other studies described in thetoxicological profile suggest that dioxins may cause damage to the liver, a loss of appetite, weightloss, and digestive disorders in humans. These effects are not anticipated from the doses ofdioxins at this site. Recent evidence suggests that dioxins may be less toxic and less carcinogenicin humans than previously thought. Consequently, the EPA is currently reevaluating its positionon dioxins (9).
Laboratory animals exposed to dioxin doses greater than those anticipated at this site havesuffered liver damage, a loss of weight, a susceptibility to infections, and reproductive effects. Inlaboratory animals, exposure to dioxins has been associated with the subsequent development ofvarious forms of cancer (9). On the basis of the ATSDR Toxicological Profile for 2,3,7,8-Tetrachlorodibenzo-p-Dioxin, the ingestion of contaminated groundwater from this site over alifetime would result in a high increased risk of contracting cancer as a result of this ingestion.
Adults and children ingesting maximally contaminated groundwater and/or ingesting soil from thissite would receive a dioxin dose from 10 to 100 times greater than the ATSDR MRL for thischemical. However, because the MRLs use safety factors, the doses received at the site are 10 to100 times less than doses that have caused effects in animals (9). Additionally, humans appear tobe less sensitive to dioxins when compared to some animal species.
Trespassers would only spend a small portion of time on the site. Therefore, exposure to dioxinin on-site soils is not likely to result in any observable adverse health effects.
Arsenic is a naturally occurring element. While pure arsenic is a gray-colored metal, arseniccompounds show a wide range of properties. Arsenic containing compounds are used in a widevariety of applications including pesticides, herbicides, and wood preservatives. According to theToxicological Profile for Arsenic, small amounts of arsenic are essential to human health (2).
At KII-F, potential and completed exposure pathways for arsenic include four sources: inhalationof air, ingestion of soil, ingestion of fish, and ingestion of groundwater. The concentration ofarsenic in air is insignificantly low and will not be further considered.
On-site subsurface soil analyses show significant amounts of arsenic. In assessing the ingestion ofsoil, a person is only likely to come into contact with soil from the upper three inches of soil,unless the soil is disturbed. Considering the environmental behavior of arsenic, the arsenicconcentrations are likely to be higher in surface soil. However, the RFI did not sample surfacesoil. Even though site visits have indicated that people trespass on the property, a trespasser isunlikely to remain on the property for greater than a few hours. Therefore, subsurface soilconcentrations of arsenic will not be further considered. However, the hypothetical ingestion ofon-site subsurface soil could produce doses approximately three times greater than the dosesproduced by groundwater. This would increase the probability of adverse health effects.
The ATSDR Toxicological Profile for Arsenic lists the health effects that may occur: "...a numberof studies indicate that, in more sensitive individuals, doses as low as 20 to µg/kg/day mayproduce one or more of the characteristic signs of arsenic toxicity, including gastrointestinalirritation, anemia, neuropathy, skin lesions, vascular lesions, and hepatic or renal injury. Theseverity of symptoms in affected individuals generally tends to increase as a function of exposureduration, although in some individuals, effects may occur after relatively brief exposure periods"(2). Thus, the same effects at KII-F may be expected following acute and chronic exposure.
Ingesting a 1/2-pound fish meal could produce an oral arsenic dose similar to doses which havecaused acute effects in humans. In the unlikely event that a person should subsist on fish from thenearby stream, this person would receive a chronic dose approximately ten times the ATSDRMRL (2).
The ingestion of off-site groundwater containing the highest concentrations of arsenic by a childwould lead to an arsenic dose similar to the doses which have caused effects in human studies. This dose is over ten times the ATSDR acute, intermediate and chronic MRL. (Chronic,intermediate, and acute effects tend to occur at similar dosages.) Additionally, studies haveassociated the ingestion of arsenic with the development of cancer in humans. The EPA hasestimated that oral arsenic doses similar to the ingestion of off-site groundwater at KII-F mayresult in a moderate increased risk of developing cancer as a result of this exposure.
2-Nitrophenol and 4-Nitrophenol
Nitrophenols are closely related chemicals with similar chemical and physical properties. They areused mainly to produce dyes, paint colorings, drugs, rubber chemicals, and substances that kill fungi (12).
Other than acutely lethal doses in animals, the ATSDR Toxicological Profile for Nitrophenols: 2-Nitrophenol, 4-Nitrophenol does not list oral studies for these chemicals. (The lethal doses areseveral orders of magnitude greater than those found at the site and therefore not considered ofconcern at this site. Respiratory effects were noted in one 13 week study at exposures similar to a13 week lethal study.) ATSDR has not derived an oral MRL for these chemicals (12).
EPA has released a draft Drinking Water and Health Advisory for 4-nitrophenol. The HealthAdvisories are 800 µg/L for one-day, and 60 µg/L for a lifetime. However, EPA's IntegratedRisk Information System (IRIS) states that, "a risk assessment for this substance/agent is underreview by an EPA workgroup. Therefore, in the interim, we can only note that the off-sitegroundwater concentrations of 4-nitrophenol is 14 times the one-day EPA Health Advisory" (21).(The EPA Health Advisories serve as guidance for levels of contaminants in drinking water whichshould not cause health effects for the specified time period.)
Data for systemic effects following intermediate inhalation exposures are confined to a singlestudy; the rats in this study displayed an increase in the levels of methemoglobin in the blood,minor signs of minimal liver toxicity, and changes in the eye. In the lack of further ingestion data,the similarity of effects that have been observed in animal studies, and the large concentrations ofthese compounds in off-site groundwater, it appears reasonable to tentatively assume that theingestion of these compounds may produce similar effects to their inhalation. However, there isno evidence that people are using groundwater containing nitrophenols. Therefore, no adversehealth effects are anticipated at this time.
Benzene is a naturally occurring substance produced by volcanoes and forest fires and is presentin many plants and animals. The ATSDR Toxicological Profile for Benzene states that it is amajor industrial chemical made from coal and oil. It is found in gasoline, glues, adhesives,household cleaning products, and art supplies (3).
Although large amounts of benzene may produce various health effects, only its carcinogenesis isof concern for the benzene detected in off-site groundwater. Exposure to benzene has beenassociated with various types of cancer in humans. The ingestion of maximally contaminated off-site groundwater over a lifetime would produce a very small but inapparent increase in thelikelihood of cancer within a population (3).
Trichlorophenol has not been made in the United States since 1986. In the past, the major uses of2,4,6-trichlorophenol were as an antiseptic and pesticide. Its uses also included preserving wood,leather and glue, and preventing the build-up of mildew on fabric according to the ATSDRToxicological Profile for 2,4,6-Trichlorophenol (16).
Other than cancer, the levels of trichlorophenol found in off-site groundwater are not likely toproduce adverse health effects. However, because several similar chemicals are present,trichlorophenol may interact with the other chemicals present.
According to the toxicological profile, laboratory animals have developed various cancers afterprolonged oral exposure to high levels of trichlorophenol. Whether or not trichlorophenol causescancer in humans has not been adequately studied (16). However, since it causes cancer inanimals, it is possible that it could cause cancer in humans. With this assumption, the lifetimeingestion of off-site groundwater could result in an increased rate of cancer. This increase,however, would not be apparent by standard statistical studies.
The amounts of dichlorophenol found in off-site groundwater, by themselves, are not of publichealth concern. However, the ATSDR Toxicological Profile for 2,4-Dichlorophenol states,"concurrent exposure to other substances that exert their toxic effects by uncoupling oxidativephosphorylation (e.g., tri-, tetra-, and pentachlorophenol) could be expected to lead to increasedadverse responses" (8). Since various other chlorophenols are present, this suggests that thetoxicity of this mixture of chemicals may be greater that anticipated by analyzing each compound individually.
Chromium is a naturally occurring element found in three different states: chromium 0, chromiumIII (trivalent chromium), and chromium VI (hexavalent chromium). In nature, most chromium istrivalent. According the ATSDR Toxicological Profile for Chromium, it is used to make steel andother alloys, bricks for metallurgical furnaces, chrome plating, the manufacture of pigments,leather tanning, wood treatment and water treatment (4).
Chromium III is an essential nutrient that helps to maintain normal metabolism of glucose (sugar),cholesterol, and fat in humans. The National Academy of Sciences Drinking Water and Health(Volume 3, page 367) states, "Compounds of chromium in the trivalent state have no establishedtoxicity. When taken by mouth they do not give rise to local or systemic effects and are poorlyabsorbed. No specific effects are known to result from inhalation. In contact with the skin theycombine with proteins in the superficial layers, but do not cause ulceration" (4).
The toxicological profile states that chromium VI is irritating to the skin and nasal passages. Inthe body it attacks the liver, kidney, and central nervous system. Inhalation of high levels ofhexavalent chromium has ben associated with an increased risk of lung cancer in humans.
At KII-F, off-site groundwater sampling has not detected the presence of hexavalent chromium. The RFI did not sample off-site surface water, sediments, or biota for hexavalent chromium. On-site soil sampling did not differentiate between the different states of chromium. The RFI did notsample off-site soil. On-site groundwater demonstrates significant amounts of hexavalent chromium.
To date, no established routes of human exposure to hexavalent chromium exist. Consequently,no adverse health effects are anticipated. However, if future sampling shows the presence ofhexavalent chromium in off-site groundwater or on- or off-site surface soil, the potential adverseeffects of chromium will need to be reevaluated.
Copper is a reddish metal that occurs naturally in rock, soil, water, sediment, and air. The Unitedstates penny displays the reddish appearance of copper. According to the ATSDR ToxicologicalProfile for Copper, it is an essential element for all known living organisms including humans andanimals (5).
Vomiting and diarrhea are two of the most sensitive indicators of oral copper toxicity. At KII-F,a child ingesting maximally contaminated off-site groundwater would receive a 1/2 dose of copperthat has resulted in vomiting and diarrhea in humans (5).
An adult ingesting 30 grams of crayfish would receive an oral dose of copper roughly equivalentto an acute dose of copper sulfate that resulted in vomiting in humans. However, because anyingested copper would be within the crayfish tissue, the adverse effects of copper may not appearin this case.
The levels of copper in the air are not of public health concern. Other than in the case of certainrare genetic diseases, such as Wilson's Disease and Menke's Disease, systemic copper toxicity isnot known in humans (5). Therefore, other than the vomiting and diarrhea listed above, copper isnot anticipated to be a public health threat.
Mercury is a chemical element that occurs naturally in several forms. The most familiar is thesilvery liquid metal used in some thermometers and other common products. Mercury also occursin combination with other elements. One form of mercury, methylmercury, can build up in certainfish (11).
The concentration of mercury detected in off-site groundwater and off-site crayfish is inadequateto produce adverse health effects. Therefore, no adverse health effects are anticipated at thepresent time. However, if future off-site groundwater samples indicate high levels of mercury, theeffects of mercury will be reevaluated.
Creosol (methylphenol) is a component of creosote (7). Sampling did not adequately determinethe concentrations of creosol present in the various media. Therefore, no further statement can bemade at this time.
ATSDR has not developed an MRL for this compound. The ingestion of maximally contaminatedoff-site groundwater by an adult would result in a dose of 2-chlorophenol approximately twiceEPA's reference dose. Because of the conservative assumptions used by EPA, the ingestion ofthis compound in off-site groundwater should not produce adverse health effects. However, if thefuture off-site concentration of this compound increases, this compound will be reevaluated.
Ethylbenzene is a colorless liquid that smells like gasoline (10). Currently, the maximumconcentration of ethylbenzene in off-site groundwater is approximately equal to the EPAMaximum Contaminant Level Goal and the EPA Lifetime Health Advisory. Therefore, no healtheffects are anticipated at this time.
Phenol is used in many manufacturing processes and products. Consumer products includeointments, ear and nose drops, cold sore lotions mouthwashes, gargles, throat lozenges, andantiseptic lotions (14). Currently, the concentrations of phenol present in off-site groundwater arenot of concern. They are less than the ATSDR acute MRL. (ATSDR has not derived a chronicMRL for phenol.) Concentrations are less than the EPA lifetime health advisory for phenol. However, phenol concentrations on-site are several orders of magnitude greater than off-siteconcentrations. Should off-site concentrations of phenol increase in the future, this chemical willneed to be reevaluated.
Adequate toxicologic information was not available for the evaluation of 2,3,5,6-tetrachlorophenol, 2,4-dimethylphenol, 2,4-dinitrophenol, 2-methyl-4,6-dinitrophenol and 4-chloro-3-methylphenol.
The State of South Carolina does not currently have an implemented database or registry dealingwith health effects in the vicinity of KII-F. Therefore, no evaluation may be made of healthoutcome data.
SCDHEC has voiced concerns over the use of private wells in the Day Street and Mustang Drivecommunities. In February and March of 1992, SCDHEC and EPA surveyed homes in areassoutheast, south, and southwest of the site. Water from identified wells was analyzed for a widerange of contaminants. No site-related contaminants were identified. Therefore, the currentconsumption of water from these wells will not result in adverse health effects. Available dataindicate that these wells could have been contaminated in the past. However, the data are notadequate to evaluate past exposures. There is a potential that these wells could becomecontaminated in the future. Therefore, this public health assessment recommends continuedmonitoring of these wells.
As listed in the section titled "Community Health Concerns," all attempts to contact communityleaders and identify any community health concerns have been unsuccessful. This Public HealthAssessment therefore recommends further work to establish a system of information exchange.