Recent data from the U.S. Environmental Protection Agency raises concerns about the harm that could be caused by contaminants being found in drinking water systems in many states. According to the agency’s data, carcinogenic chemicals — substances known or suspected to cause cancer — are in water that millions of people are drinking. Paul Westerhoff, a professor in the School of Sustainable Engineering and the Built Environment, part of the Fulton Schools, says various water utilities throughout the country have different water sampling practices and states have different reporting requirements, both of which could hamper maintaining timely and accurate data and instituting needed water safety regulatory efforts.