Wonder how much penicillin, estrogen or acetaminophen is percolating through Utah's water system?

Until Utah's Division of Water Quality adopts a standard for measuring those specific chemicals in the state's waterways, that might be a difficult question to answer.

Low levels of a variety of medications — including antibiotics, pain pills and drugs used to treat mental illnesses — have been found in the drinking-water supplies of 24 major metropolitan areas. But not all states, including Utah, specifically test for the chemicals. Until the Environmental Protection Agency sets a standard for pharmaceuticals in water, that's not likely to change here.

"It's a concern right now, but I am not alarmed because I haven't seen any data from EPA that would suggest we've got an overwhelming pollution problem caused by these complex chemicals," said Walt Baker, director of water quality for the Utah Division of Water Quality. "The jury is still out. We're studying it, and hopefully EPA will provide some guidance to the states that will help us protect our waters."

EPA has identified 129 priority pollutants that the Division of Water Quality watches for in Utah's water system. But with some 10,400 miles of streams in the state that require monitoring, Baker says the division doesn't do tests on each of the 129 pollutants in every stream.

Without a criteria to limit, say, acetaminophen — the painkiller known as Tylenol — Baker says the division does not take measurements or track the substance. Each pharmaceutical drug is made of complex chemical compounds, which might show up on a routine test, but without a knowledge of what the compound structure is, the drug is unrecognizable.

It is thought that drugs are entering the water supply through human waste, which passes through treatment facilities, or through people flushing their pills, which also goes into the waste system.

"By and large, these pollutants are not to the concentration level that would pose a risk to human health," Baker said. "It's more a problem for the aquatic habitat and the aquatic life. Their threshold ... is much, much lower than it would be for humans."

Some effects on fish have already been traced to pharmaceuticals. That's what alarms Great Salt Lakekeeper executive director Jeff Salt. The nonprofit organization focuses on water-quality issues, and limiting the amount of drugs that pass through the waste treatment process is a necessary step in preserving Utah's water quality, Salt says.