Hazardous legacies in the Great Lakes basin

Session: Poster session

Emily Shaw, Michigan Technological Univ., [email protected]
Noel Urban, Dept. Civil & Environment Eng., Michigan Technological Univ., [email protected]
Mugdha Priyadarshini, Michigan Technological Univ., [email protected]

Abstract

Polychlorinated biphenyls (PCBs) are ubiquitous contaminants worldwide and are the most frequent at US and bi-national areas of concern (AOC). To address this hazardous legacy, annex 1 of the 1972 Great Lakes Water Quality Agreement classified AOCs as sites with one or more significant beneficial use impairment (BUI). Both Canada and the US committed to identifying and remediating BUIs in consultation with the surrounding communities. This study evaluated existing evidence to answer the questions: do existing practices enable accurate and reliable evaluation of PCB contamination at AOC sites and have remediation efforts been effective? Using fish PCB data from the Michigan Department of Environmental Quality (MDEQ), statistical analyses indicated significant differences in the magnitude of contamination and the overall toxicity among fish species. A comparison of the contamination at AOC and non-AOC sites suggests insignificant differences between them. Toxicity of fish at AOC and non-AOC sites exceeded the EPA’s dioxin-like compound reference dose of 0.7 pg/kg/day, in spite of all dioxin-like and most mono-ortho substituted congeners being in <50% of the samples. The similarity between AOC and non-AOC sites support recommendations for altering the current monitoring strategies to better evaluate PCB contamination and efforts to remediate such sites.

1. Keyword
PCBs

2. Keyword
fish

4. Additional Keyword
Areas of Concern