A study of 22 locations on the Ohio River revealed the DuPont chemical C8 was present in every sample collected along the 981-mile stretch from Pennsylvania to Kentucky.
C8 or PFOA, also known as perfluorooctanoic acid, was found in measurable levels ranging from 35.2 to 2.04 parts per trillion. No sampling was performed near DuPont Washington Works where the chemical has been used for more than 50 years in the manufacture of Teflon.
The highest concentration of the manmade chemical was found in the river near Ravenswood, West Virginia where sampling detected levels of 35.2 parts per trillion. A level of 31.2 parts per trillion was identified near Paducah, Kentucky and a concentration of 19.1 parts per trillion was found near Huntington, West Virginia.
The study was performed by ORSANCO (Ohio River Sanitation Commission) in collaboration with the US Environmental Protection Agency in September 2009 to detect a total of 158 compounds considered contaminants of emerging concern, including 118 pharmaceutical and personal care products, 27 hormones and sterols, and 13 perfluorinated compounds.
“The study was designed to generate data as preliminary survey by the Commission and results would be used to guide future actions,” according to the report released in May. “It has been shown that wastewater treatment plants are not currently designed to remove these chemicals to the very low levels, nor are they required by regulatory agencies to do so.”
The provisional health advisory established by the US EPA for PFOA in drinking water is 400 parts per trillion. Though the New Jersey Department of Environmental Protection has set a more prohibitive drinking water guidance value of 40 parts per trillion.
“There are no state or national water quality standards established for the compounds targeted in this study in U.S. surface waters,” according to ORSANCO.
The locations were targeted for sampling based on their proximity to major urban areas, effluent influence, or because they fell within areas of the river that had relatively few local upstream potential sources.
Marietta is located at Ohio River mile 172. Nearest sampling was performed at Ohio River mile 91.3 and Ohio River mile 220.3 (Ravenswood).
PFOA has been targeted by US EPA for elimination from industrial emissions by 2015 because of its classification as a likely human carcinogen.
PFOA by PPT / Location / Ohio River Mile
35.2 / Ravenswood, WV / 220.3
31.2 / Paducah, KY / 935.9
23.9 / Paducah, KY / 934.4
19.1 / Huntington, WV / 306.8
18.2 / Evansville, IN / 791.8
14.4 / Cincinnati, OH / 478
14.3 / Mill Creek Tributary
14.1 / Manchester, OH / 394.9
13.1 / Cincinnati, OH / 462.9
11.5 / Evansville, IN / 791.5
9.44 / / 612.2
9.21 / Louisville, KY / 600.5
8.93 / Concord, KY / 889.1
6.22 / Scioto Tributary
5.39 / / 91.3
3.87 / Monongahela Tributary
3.43 / Wabash Tributary
3.41 / / 3.1
3.01 / / 86.7
2.5 / / 9.7
2.04 / Allegheny Tributary
1.48 / Kanawha Tributary