Millions of people across the United States could be drinking water contaminated with dangerous levels of substances created when utilities disinfect water tainted with animal manure and other pollutants, according to a report released Thursday. An analysis of testing results from community water systems in 49 states found that nearly 6,000 such systems serving 122 million people recorded an unsafe level of chemicals known as trihalomethanes at least once during testing from 2019 to 2023. … New York, Oklahoma, California and Illinois followed Texas with hundreds of water systems in each of those states showing higher-than-allowed levels of TTHMs during the testing period, the EWG report found. More than 64.5 million people are served by 3,170 systems in the ten states that had the most violations.