What are Contaminants of emerging concern (CECs)?
Contaminants of emerging concern (CECs) are broadly described as chemicals or materials that are not yet regulated by EPA but may potentially pose threat to human health or the environment. These contaminants include endocrine disrupting compounds (EDCs), pharmaceutical drugs and personal care products (PPCPs), persistent organic pollutants, or nanomaterials. They are increasingly being detected as analytical technology advances, mostly at low levels in the surface water. It is important to know that, because of their emerging nature and the knowledge about these chemicals are still in its infancy, the levels at which they become a threat, reliable analytical and treatment technologies, and the sources and the routes of exposure are not well understood.
What Is WSSC Doing?
To assure our customers continue to get safe drinking water, WSSC and its partners in the industry have studied the issue for over a decade. First, working with two regional partners and coordinating with the Metropolitan Washington Council of Governments (COG), WSSC collected samples from the Potomac and Patuxent rivers. Tests showed the presence of extremely small amounts of CECs in the area’s water supply. These low level detections do not necessarily indicate a concern to human health. Second, pursuant to EPA’s Unregulated Contaminants Monitoring Regulations (UCMR) as well as related Maryland law, WSSC monitors groups of contaminants in treated waters produced at Potomac and Patuxent water Filtration plants on a regular basis. These contaminants are identified by EPA based on the latest knowledge of nationwide occurrence and human health impacts, and are renewed every five years. A detailed information of UCMR and historical data of detected contaminants can be found here. Lastly, WSSC voluntarily monitors some of the CECs based on known or suspected risks at our water system. These contaminants include hexavalent chromium, cyanotoxins, and PFAS. A more detailed information about these contaminants and WSSC’s monitoring results can be found in the links below.