MATTOON, COLES COUNTY, ILLINOIS
Concentrations of each soil and sediment contaminant were compared with the appropriate comparison value used to select contaminants for further evaluation for carcinogenic and non-carcinogenic health effects (Attachment 5). Soil and sediment samples were also compared to typical Illinois background soil concentrations for inorganic contaminants . Contaminants that exceeded comparison values or for which no comparison value was available were further evaluated.
Contaminants on site that were present at levels above comparison values are shown in Table 1. People could be exposed to contaminants in soil and sediment through the incidental ingestion and inhalation of contaminated dusts and dermal contact. Populations likely to be exposed are site workers, people conducting business at the facility, and site trespassers, such as children looking for bicycle parts (Table 2). Assumptions used to evaluate potential exposure include:
- workers are adults working on the site 5 days per week, 50 weeks per year,
- persons conducting business are adults visiting the site 2 hours each work day, and
- trespassers are children coming briefly onto the site up to 5 days per week for 9 months of the year.
Polycyclic aromatic hydrocarbons (PAHs) were detected in samples X101, X102, X104, X106, X201, and X202. PAHs are a group of chemicals that are formed during the incomplete burning of coal, oil, gas, wood, garbage, or other organic substances, such as tobacco and charbroiled meat. PAHs can be found in soils virtually everywhere. The PAHs found on the site are phenanthrene, benzo(a)pyerene [B(a)P], chrysene, and dibenz(a,h)anthracene. The U.S. Environmental Protection Agency (USEPA) classifies some PAHs, such as B(a)P, as probable human carcinogens. Exposures to these PAHs have been linked to cancers of the liver, skin, and scrotum . Based on the maximum concentrations detected on and off the site, exposures to PAHs would not be expected to cause any adverse health effects.
Hepatachlor epoxide is a breakdown product of heptachlor, an insecticide used in homes, buildings, and food crops. Heptachlor epoxide exists in soil because of past usage of heptachlor for both agricultural and nonagricultural purposes . According to a National Soils Monitoring Program, heptachlor epoxide was detected in crop land soils at concentrations ranging from 100-430 parts per billion (ppb). It was detected in two on-site samples (X101-102) at levels above comparison values. However, exposure to site-related heptachlor epoxide is not likely to result in cancer or non-carcinogenic health effects for adults (e.g., workers) and children because the exposure dose calculated using our exposure assumptions would not result in a dose that is associated with any increased cancer risk.
Arochlors were also detected in several samples on site (X101-103, X106-107). Arochlors are commercial polychlorinated biphenyl (PCB) mixtures produced in the U.S. before 1977 . The toxicities of different arochlors depend on the PCB congener present in the mixture. Congeners with a greater percentage of chlorine by weight are more toxic. Arochlor-1260 is 60% chlorine by weight and is considered the most toxic. No comparison values are available for the individual arochlors detected on site. Since the comparison values for PCBs are based on the toxicity of Arochlor-1260, the arochlors present were evaluated relative to Arochlor-1260. The inhalation dose was considered minimal because airborne particulates are usually too large to enter the lung. The estimated ingestion and dermal doses are below the Agency for Toxic Substances and Disease Registry (ATSDR) chronic oral minimum risk levels (MRLs). Exposure doses below MRLs are not expected to result in adverse health effects. IDPH staff also evaluated cancer risk. No apparent increased risk of developing cancer from exposure to site-related arochlors exists for our exposure scenarios.
2-methylnapthalene is used to make dyes, resins, and vitamin K. It can be found in cigarette smoke, wood smoke, tar, and asphalt. The compound 2-methylnapthalene does not cling strongly to soils and sediments . In surface soils, it will most likely evaporate into the air; in deeper soils it will be broken down by microorganisms. Methylnapthalenes have been reported at low levels in soils and sediments. Methylnapthalenes were reported at much lower levels (2.9 ppb) in PAH-contaminated soil . Exposure to the levels of methylnaphthalenes found is not expected to result in adverse health effects.
Lead occurs naturally in the environment; however, it mostly enters the environment as a result of human activities. Lead is commonly found in a variety of products, including ammunition, batteries, solder, caulking, paints, and gasoline. Exposure to lead is of particular concern with children. Exposure to elevated levels of lead may lead to nervous system damage, such as decreased intelligence quotient (IQ) scores, reduced concentration, and reduced growth in young children. In adults, lead exposure may cause decreased reaction time, memory loss, and anemia . Kidney and brain damage is also possible in adults and children at high doses. The IDPH Lead Poisoning Prevention Code (Part 845) state that the maximum allowable concentration of lead in soil readily accessible to children is 1,000 parts per million (ppm). Exposure of very young children to lead-contaminated soil is unlikely, and exposure of older children would likely be infrequent. Therefore, no adverse health effects are likely to occur should anyone be exposed to lead at the site.
Copper was elevated in four on-site samples (X101, X102, X104, X107). Although copper levels were elevated in sample X107, levels were not elevated in the duplicate sample, X106. No comparison values have been developed for copper in soil or sediment. Illinois soils generally contain between 1 and 156 ppm of copper . Copper is necessary for maintaining good health. The recommended daily allowance (RDA) for copper for an adult is 2-3 mg/day, which is equivalent to a dose ranging from .0286 to .0429 mg/kg/day . Exposures to copper at its maximum concentration on site would result in estimated adult oral and dermal doses less than the RDA. No adverse health effects would be expected from exposure to copper.
Iron is a compound that occurs naturally in the environment, including soils. The iron concentration detected in sample X104 was greater than Illinois background soil levels; however, this sample was collected from soil between the two piles of iron cuttings. No adverse health effects would be expected from exposure to iron on the site.
No comparison values were available to evaluate the following contaminants:
Each contaminant was detected at a level less than 2 ppm. The detection frequency was less than 50 percent for all chemicals, except endrin aldehyde (63%). In addition, carbazole and 4-nitroaniline were detected in only sample X107, but not in a duplicate sample.