Drinking water in Arlington, Texas, tested positive for trace concentrations of the anti-anxiety medication meprobamate, city officials revealed Monday in response to a series of public records requests. In a February interview with The Associated Press, Mayor Robert Cluck said trace concentrations of one pharmaceutical had been found in treated drinking water, but he declined to name it. He said revealing the name in the post-9/11 world could cause a terrorist to intentionally release more of the drug, causing harm to residents. "I don't want to take that chance," Cluck said. "There is no public hazard, and I don't want to create one." Monday's identification of meprobamate came after the Texas attorney general said those concerns were not well founded. In water samples taken in October 2006, concentrations of the drug measured around 1 part per trillion, far below the levels of a medical dose. Water department officials say their drinking water meets the highest standard of quality. The AP reported in March that trace concentrations of pharmaceuticals have been detected in drinking water systems for 24 major U.S. metropolitan areas, affecting 41 million Americans. As part of that series, the AP contacted Arlington officials and learned water there had been tested, but the city near Dallas was the only place in the United States included in the AP PharmaWater series that refused to release its drinking water test results. Cluck, a medical doctor, had directed local officials in 2006 to conduct tests after hearing that traces of Prozac had been found in water elsewhere in Texas. The tests are not required under federal or state regulations. After the AP's story was distributed, Arlington officials provided a few more details: trace concentrations of five pharmaceuticals — one antibiotic, two anti-seizure medications, one pain reliever and one minor tranquilizer — had been detected in the city's untreated source water. The city also named the five: sulfamethoxazole, dilantin, carbamazepine, naproxen and meprobamate. But it declined at that time to identify which one also had been detected in treated drinking water. Nine different individuals in and near Arlington including reporters, attorneys and citizens submitted legal public records requests to the city demanding the release of the specific test results. "I was driving to work one morning when I heard the mayor on the radio say he was not going to tell the public what this substance was because he was worried about terrorism," said Frank Hill, an attorney in Arlington who requested the records. "That struck me as so disingenuous and typical of the city of Arlington that I just couldn't let it rest. This is our water, and our money paid for those tests." In an editorial in March, the Fort Worth Star-Telegram said that while Cluck "deserves kudos for anticipating the problem" he should let people know what the tests found. The city refused, prompting the attorney general to weigh in. In May the attorney general's office responded that there was no proof that telling residents what has been found in their drinking water would help terrorists contaminate their supplies. Arlington had until Monday at 5 p.m. to release the results or sue the attorney general. Mayor Cluck said Monday he didn't think it was safe to reveal any information about what compounds can and can't make it through Arlington's drinking water treatment plant. "I do not feel comfortable releasing the names of what's in our water supply and gets past our water treatment plant, even if it's in parts per trillion. I don't like the concept of releasing this information because there are people who want to do us harm. But once the attorney general said go for it, we did." Meanwhile, Arlington Water Utilities has posted a notice on its website that describes how pharmaceutical compounds and personal care products are being found at low levels in many of the nation's lakes, rivers and streams. The agency says the mayor "is leading us to do more comprehensive testing and further research of our treatment processes as more scientific research is conducted." Copyright 2008 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Guidelines: You share in the USA TODAY community, so please keep your comments smart and civil. Don't attack other readers personally, and keep your language decent. Use the "Report Abuse" button to make a difference. You share in the USA TODAY community, so please keep your comments smart and civil. Don't attack other readers personally, and keep your language decent. Use the "Report Abuse" button to make a difference. Read more