Your drinking water may contain chemicals that could adversely affect your health, a new study has found.The nonprofit Environmental Working Group, a research and advocacy organization, said new laboratory tests show exposure to chemicals in drinking water in the U.S. has been "far more prevalent than previously reported."Scientists with the organization believe the chemicals, known as PFAS or "forever chemicals," are likely found in every major water supply in the country, the group said.According to the Environmental Protection Agency, the chemicals are used in household items such as nonstick and cleaning products, as well as things ranging from firefighting foams to pizza boxes. Exposure to the chemicals can have adverse health effects that include low weight in babies and cancer.The results affect dozens of areas that haven't been cited by federal or state environmental agencies, according to the nonprofit.The Environmental Working Group is using the results to push state and federal policymakers to improve water standards and make other changes.