Every contaminant detected nationwide is listed in their database to give more insight on how they might be affecting your health. EWG standards are not based on compromises that polluters and politicians find acceptable, or what it will cost to clean up drinking water supplies. Rather, to arrive at these standards, EWG reviewed the best and latest scientific evidence, legal standards and health advisories, and then have defined water quality goals that will protect public health.

DCEG researchers in the Occupational and Environmental Epidemiology Branch (OEEB) investigate a number of water contaminants that are thought to be associated with cancer risk. These include naturally-occurring substances, like arsenic, fertilizer by-products like nitrate, as well as disinfection byproducts (DBP), which are compounds formed when chlorine used to disinfect water comes into contact with organic material in water.

Results of a new survey conducted for NSF, a global public health and safety organization, reveal that while most U.S. consumers drink tap water (71 percent) and more than half (55 percent) are concerned about contaminants in their drinking water or don’t know what’s in it, nearly half (42 percent) do not take steps to filter or treat their home’s drinking water.

PFAS are known as “forever chemicals” because once released into the environment they do not break down and they can build up in our blood and organs. The Centers for Disease Control and Prevention has detected PFAS in the blood of 99 percent of Americans, including newborn babies. The initial round of data that the agency released in August, 2023 confirms the presence of PFAS at 431 water systems at levels above minimum reporting limits. This is consistent with a 2020 study published by scientists at the Environmental Working Group that estimated more than 200 million Americans could have PFAS in their drinking water. 

Summaries and educational materials (toolkits, handouts, infographics, etc.) which are publicly available resources by the Water Quality Research Foundation. Featured are a Contaminant Occurrence Project & Interactive Map, Predictive Modeling of Drinking Water Crises, Emerging Contaminant Consumer Study, Sustainability Comparison Study, and more.