University of Iowa News Release
July 8, 2004
Photo: Associate Professor Keri Hornbuckle of the UI College of Engineering Department of Civil and Environmental Engineering
UI Researchers Find Consumer Product Chemicals In Great Lakes
University of Iowa researchers have found chemical ingredients used to coat cookware, furniture and other consumer products in water samples taken from the Great Lakes.
Doctoral student Bryan Boulanger, Associate Professor Keri Hornbuckle and Professor Jerry Schnoor of the UI College of Engineering Department of Civil and Environmental Engineering, together with University Hygienic Laboratory chemist John Vargo, report their findings in the June 22 online version and the August 1 print edition of Environmental Science & Technology (ES&T).
Used to repel fabric stains and prevent food from sticking to pans, the chemicals have recently been found in fish, birds and mammals in the Great Lakes. However, the chemicals -- perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) -- hadn't previously been identified in major bodies of water. The researchers found PFOS and PFOA concentrations ranged from 21-70 and 27-50 nanograms per liter in 16 water samples taken from Lake Erie and Lake Ontario, respectively. The researchers also identified chemicals in the samples that can break down into PFOS, suggesting members of the chemical compound class may be more widely distributed than previously known.
"These are the first reported concentrations of perflurooctane surfactants in Great Lakes water and the first report of PFOS precursors in any water body," Hornbuckle says.
"Although the concentrations are very low, and not likely to have direct toxic effects, our findings are important because we now know that natural waters may be a pathway for these compounds to reach aquatic food webs," she says.
"The presence of this compound class in the environment is of concern because PFOS and PFOA have accumulated to measurable levels in biota. Continued accumulation of these compounds may lead to observed ecotoxicity effects. Perfluorooctane surfactants are known to cause acute and subchronic toxicity effects in laboratory studies," she says.
The raw water samples for the test were collected from Aug. 7-12, 2003 while onboard the Environmental Protection Agency (EPA) ship R/V Lake Guardian and were taken at a depth of approximately four meters at four locations in Lake Erie and four sites in Lake Ontario. The sites were chosen to reflect urban influence and remote locations, as well as to provide a sample from eastern, central and western portions of each lake.
Hornbuckle and her colleagues say that the ultimate value of the study may be to provide data useful in assessing the impact of water exposure on the accumulation of perfluorooctane surfactants in an ecosystem.
ES&T is a peer-reviewed publication of the American Chemical Society, the world's largest scientific society.
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