“WILMINGTON – Mary Alice Hinshaw pulled out a report detailing test results of water from her home, one of 198 sampled as part of the first study on the human health effects of GenX and related substances recently found in New Hanover County’s drinking water.
She turned to a graph showing the distribution of GenX levels in all homes tested, each plotted as a black dot, most of them tightly clustered into a flattened diamond with results between 25 parts per trillion and 75 ppt. Three strays stood out above the rest.
‘See that little dot right there, right at the top?’ Hinshaw said. ‘That’s our house. We’re at 100 parts per trillion.’
Hinshaw and her husband, Skip, were among about 75 people at a forum Tuesday night at the University of North Carolina Wilmington, where members of a North Carolina State University science team conducting the study answered questions about the water tests.
What the science team releases next, likely not until late summer, no doubt will be far more interesting: analyses of blood from the Hinshaws and about 300 other study participants who live in the homes where water was sampled. Some homes had more than one participant. Researchers are also developing methods for urine tests, and those results will likely come later.
‘What we will have is the first study on these substances in the human body,’ said lead investigator Jane Hoppin, a professor in the department of biological sciences and deputy director of the Center for Human Health and the Environment at N.C. State.
Begun last year, the study was funded by a $275,000 grant from the National Institute of Environmental Health Sciences, or NIEHS.
Researchers tested tap water for 17 substances, finding most of them in at least some homes. Guidelines for safe concentrations in drinking water exist for just three of the 17. The North Carolina Department of Health and Human Services last year established an ‘interim health goal’ of 140 ppt for GenX. The U.S. Environmental Protection Agency set a ‘lifetime health advisory’ of 70 ppt for PFOA, also known as C8, and PFOS, at 70 ppt either individually or in combination. None of the N.C. State study results exceeded those levels.
For three of the substances targeted — Nafion byproduct 2, PFMOAA and PFO2HxA — researchers lacked benchmark samples needed to ‘train’ their equipment. So while they detected the presence of those chemicals, they could not definitively determine concentrations. Even so, data collected indicated average concentrations of those three may be greater than that of GenX.
‘It was important to do these water analyses to give us a sense of the current exposure levels,’ said Nadine Kotlarz, an N.C. State postdoctoral researcher who is leading the sample analysis. ‘They’re not representative of exposure in the long term. It’s important to remember that prior to June 21, on average there were about 600 ppt of GenX in the treated water and sometimes as high as 4,500 ppt in the treated water.’
‘The blood levels may be able to give us more information about long-term exposure of individuals living in Wilmington,’ Kotlarz said.”
Read the full article by Vaughn Hagerty