TP20 Ecological Risk Assessment
Tuesday, 15 November 2005: 8:00 AM - 6:30 PM in Exhibit Hall

(JOH-1117-835163) Are South Chattanoogan residents and wildlife at risk to locally occurring contaminants: 1. Exposure Assessment.

Hussar, E.¹, Morris, C.¹, Campbell, M.², Lin, Z-Q^{1, 3}, Richards, S.², Johnson, K.^{1, 4}, ¹ Environmental Sciences Program, Southern Illinois University Edwardsville, Edwardsville, IL, USA² Department of Biological and Environmental Sciences, University of Tennessee at Chattanooga, Chattanooga, TN, USA³ Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL, USA⁴ Department of Chemistry, Southern Illinois University Edwardsville, Edwardsville, IL, USA

ABSTRACT- South Chattanooga, TN has been home to foundries, coke furnaces, chemical, wood preserving, tanning and textile plants for over 100 years. As a result of the dumping of wastes into the creek, subsequent flooding, run-off and atmospheric deposition the sediment and adjacent soil of Chattanooga Creek is contaminated with polycyclic aromatic hydrocarbons. Currently, 42 hazardous waste sites are located in South Chattanooga, 13 of these sites are listed as state or federal Superfund sites. Mixed among these sites are three large public housing complexes, schools, and single-family residences. Many of these public areas that surround the Chattanooga Creek are suspected of having multiple pollutants due to clandestine dumping and transfer via flooding. This concerns South Chattanoogans and ATSDR. To address these concerns, we focused on Arsenic and 16 PAH priority pollutants in residential and public areas of South Chattanooga, as well as the Chattanooga Creek floodplain. The overall goals of this exposure assessment are to measure the potential for exposure to PAHs from soils. The initial exposure estimate is incorporated into a probabilistic risk assessment for humans residing in South Chattanooga. Sixty samples were collected from 20 sampling sites (n=3 from each site) throughout Chattanooga neighborhoods, as well as along the banks of Chattanooga Creek. Arsenic was found in 100% of the samples and ranged from 19.7 mg/kg to 124 mg/kg. Benzo(a)pyrene was detected in 98.2% of the samples. B(a)P, benzo(a)anthracene, chrysene, and indeno(1,2,3-c,d)pyrene are all probable human carcinogens and were found ranging in concentration from not detectable to 21.9 ppm, not detectable to 13.2 ppm, 0.028- to 12.3 ppm, and 0.028- to 28.4 ppm, respectively. Total PAHs ranged from 0.35 ppm to 163 ppm. Preliminary indications are that there are areas that may pose risk to humans and wildlife as addressed in part two of the study.

Key words: polycyclic aromatic hydrocarbons, arsenic, Chattanooga, risk assessment