Perfluoroalkyl compounds (PFAS) are manmade chemicals that are characterized by very stable carbon chains that allow them to act as a strong repellent to oil, water, and stains from other liquids. These desirable properties mean they are found in hundreds of consumer products as well as in firefighting foams.
There are more than 1,000 forms of PFAS compounds that have different chemical makeups and properties and different levels of toxicity. To date, the most commonly found PFAS compounds are ‘perfluorooctanoic acid’ (PFOA) and ‘perfluorooctanesulfonic acid’ (PFOS).
These forms have long carbon chains, do not readily break down in the environment, are water soluble, and have been found in some New Hampshire groundwater supplies at elevated levels.
The public health concern is for PFAS to be consumed, absorbed and accumulated in the body at toxic levels. Although more research is needed, initial scientific studies indicate that long-chain compounds like PFOA and PFOS may cause developmental effects in infants, interfere with the body’s natural hormones, increase cholesterol levels, affect the immune system and increase the risk of cancer. Scientists are still learning about the health effects of PFAS and their toxicity, though it is believed that the PFAS compounds having shorter carbon chains are potentially less toxic since they remain in the bloodstream for shorter periods of time.
Are these compounds in your public water supply?
In 2017, EPA recommended PFAS levels they believed would not lead to toxicity while allowing states to consider more stringent levels for compounds of concern. The NH Department of Environmental Services (DES) has been working diligently on amendments to their drinking water rules to protect public health and the environment from PFAS in our drinking water. New rules were recently adopted that will affect every public water system in the State of New Hampshire.
Last week, Hoyle, Tanner’s water quality experts attended the NH Drinking Water Exposition and Tradeshow learning about New Hampshire’s new PFAS limits. DES submitted amended public drinking water rules in July 2019 to the state legislature which voted in favor of the new standards. The new standards became effective on September 29, 2019 setting the Maximum Contaminant Levels (MCL) in public drinking water for specific PFAS compounds as follows:
- PFHxS = 18 ppt
- PFNA = 11 ppt
- PFOS = 15 ppt
- PFOA = 12 ppt
The new rules require public water supplies to begin sampling and reporting levels of these four PFAS compounds beginning in the fourth quarter of 2019 (Oct-Dec) with continued quarterly sampling and reporting in 2020 and beyond. The regulatory thresholds will be based on a 4-quarter running average for each of the PFAS compounds with compliance indicated by a 4-quarter average that is less than the MCL for each compound.
By January 2020, DES will be submitting draft rules on PFAS in surface water to the New Hampshire legislature – more to come on this front!
Proper sampling is critical to avoid contaminating samples. Many communities are not equipped to perform the sampling themselves and will rely on certified laboratories for proper sampling, analytical methods, and meeting the quarterly sampling and reporting schedule.
The DES Water Quality Experts
Hoyle, Tanner’s water quality engineers are committed to keeping at the forefront of emerging regulations and technologies to be able to better serve the communities where we live and work. You may contact me, Joe Ducharme, Regional Manager of Environmental Services, at 603-669-5555, x-142 or email me with any questions or water quality needs – we are here to help!