State officials have released the first results of water quality samples and an updated preliminary health assessment for concentrations of the unregulated compound GenX in drinking water.
On June 12, the NC Department of Health and Human Services shared a preliminary health protective level of 70,909 parts per trillion for GenX, more than 100 times greater than the average concentration of 631 parts per trillion found in the Cape Fear River in samples taken in 2013-14 by researchers measuring for the chemical. As such, officials stated the 631 ppt “would be expected to pose a low risk to human health,” based on calculations used to determine the 70,909 parts per trillion figure.
On Friday, DHHS released an updated health goal, which is described as a non-regulatory, non-enforceable level of contamination below which no adverse health effects would be expected over a lifetime of exposure, to 140 ppt -- more than 4.5 times the 2013-14 average concentration of 631 ppt, and more than 500 times the initial health protective level of 70,909 ppt issued last month.
State regulators collected samples at 13 sites in the Wilmington and Fayetteville areas between June 19 and July 6. Results show higher concentrations near the point where Chemours’ Fayetteville manufacturing facility was discharging GenX into the Cape Fear River, and much lower concentrations at the public water supply systems near the facility and 70 miles downstream in the Wilmington area.
As shown in the figure above, the concentration of GenX in Cape Fear Public Utility Authority's finished water on June 22, one day after Chemours stopped some of the GenX discharge into the river, was 1100 ppt in the sample analyzed by Test America (a lab under contract to Chemours), and 726 ppt in the sample analyzed by the EPA lab -- nearly eight times and just over five times, respectively, of the newly set health goal of 140 ppt. That number decreased to non-detectable and 87 ppt, respectively, in the July 6 sample. Finished water in both Brunswick and Pender counties followed a similar trend.
“Our goal is to protect the safety and health of all North Carolinians,” said Mandy Cohen, secretary of the DHHS. “We are working closely with our partners at the Department of Environmental Quality to understand and communicate information in a timely manner, to help those impacted.”
A statement from the office of New Hanover County Health Director Phillip Tarte mentioned optimism and a need to do more.
"The data from the state shows that the level of GenX in our water is substantially trending downward, and it is less than what was observed in the 2013 study," the statement read. "More research has to be done by the state and by the EPA on the human health effects, and more must be done to stop the discharge of any and all unregulated compounds into the Cape Fear River."
Six other perfluoroalkyl ether carboxylic acids (PFECAs) structurally similar to GenX were not included in the data released on Friday. In a Cape Fear Public Utility Authority study, several of those PFECAs exhibited peak areas two to 113 times greater than GenX.
Copyright 2017 WECT. All rights reserved.