ST. MARY’S CITY, Md. – Last month, the St. Mary’s River Watershed Association tested the tidal waters of the St. Mary’s River for per- and polyfluoroalkyl substances, a group of over 4,700 compounds known collectively as “PFAS.” The laboratory analysis reported that at least one PFAS compound was detected at six of the ten sites studied. In the water samples collected at these six sites, the laboratory reported PFAS levels that ranged from 5.1 to 9.1 parts per trillion (ppt).

“These numbers are not alarming,” said Bob Lewis, executive director of the Association. “PFAS are found in so many things we use or wear every day. We all have detectable levels in our blood. Even the rain can carry minute amounts of these compounds.”

In early March, the Navy hosted a public meeting to inform the public of its work to terminate the use of PFAS compounds that cause adverse health impacts, to locate sites on Base where PFAS are present, and to clean up these polluted sites. Over 200 countians attended the meeting.

The Association contracted a laboratory certified by the EPA for PFAS testing. The equipment they use is state-of-the-art. PFAS are measured in tiny amounts—parts per trillion (ppt)—making sampling and analysis very technical and difficult. The Association has great confidence in their testing program and the final data.

At five sites, the compound 1H,1H,2H,2H-perfluorodecanesulfonate (8:2 FTS) was detected at levels from 5.1 to 9.1 ppt. Church Cove was the highest and Horse Shoe Point was the lowest. The other three sites were Windmill Point, Broom Creek, and Seminary. Perfluoropentanoic acid (PFPeA) was reported at one site near the mouth of St. Inigoes Creek, Raleys Shore, at 7.6 ppt.

“We tested for 28 compounds using the same EPA protocols that the Department of Defense uses. These are the only two compounds we can definitively say are in the water,” said Lewis.

Testing was also completed on oysters at six sites and no PFAS was detected. The laboratory’s method of detection in oysters was 1000 times higher than in the water samples suggesting that further study is needed. The Association has shared the lab results with the Maryland Department of the Environment (MDE) for their review and interpretation regarding public health safety of both the waters and shellfish.

MDE will be conducting their PFAS testing of waters and oysters in the St. Mary’s River this summer and we can expect results in the fall. Currently, Maryland has no regulatory standards for PFAS pollution, although an aggressive effort is underway to test and filter, if necessary, drinking water throughout the state. Sixteen states have at least a drinking water maximum level for PFAS either in effect or coming into effect this calendar year. The EPA has no regulatory standards for PFAS pollution.

“We’ll know more about PFAS pollution in the St. Mary’s River when the state completes their testing program,” said Lewis. “Our study suggests that the St. Mary’s River may be a lot like many other tidal waters up and down the east coast where people have congregated and use PFAS laden products on a daily basis.”

PFAS can be found in sunscreens, cosmetics, clothing, polishes, paints, and food containers—just to mention a few of the most common products we use daily. The Association plans to publish on its website a white paper “PFAS in St. Mary’s” by the end of this month.