Remember that whole “pee” controversy? Last year, media reports may have spooked some from swimming after a study concluded that urinating in indoor pools may lead to respiratory issues. Some of the same researchers have moved on to another aspect of pool water. This time they’ve zeroed in on pharmaceuticals and personal care products as potential health hazards. And, once again, it has spurred media coverage that some observers find prematurely alarmist.

Scientists from the Georgia Institute of Technology, Purdue University and the Chinese Academy of Sciences analyzed water samples from indoor swimming pools and detected trace amounts of the insect repellent ingredient N,N-diethyl-meta-toluamide (known as DEET); the flame retardant Tris(2-chloroethyl)-phosphate (or TCEP); and caffeine.

Their concern is that compounds from prescription drugs excreted through sweat, urine and topical applications, such as deodorant and sunscreen, could interact with chlorine to produce harmful byproducts.

The good news? There is no cause for alarm, at least not yet. While the ongoing research has identified the presence of the substances, no work has been done yet to determine if they are harmful. “It may turn out, at least in some cases, that there really is nothing to worry about, but we just don’t know that at this point,” said one of the authors, Ernest R. Blatchley III, professor of environmental and ecological engineering at Purdue. He also contributed to last year’s study suggesting a link between urine and air quality concerns.
In fact, written materials from the scientists do not outline theories as to potential consequences of the byproducts, but state that “... there is this unknown potential for them to bring about undesired or unexpected effects in an exposed population.”

Yet the press would have some believe we’re swimming in a pharmaceutical stew.

“Prescription Drugs Taint Pool Water,” stated Newsmax Health.

The Daily Mail asked: “What are YOU Swimming In?”

And a Huffington Post UK article suggested that people ditch chlorinated pools in favor of natural swimming holes.

Such reactions leave pool and spa professionals with mixed feelings about this sort of study. For his part, Blatchley said the industry has been largely supportive. However, others think research like this only inspires disproportionate concern.

“From a risk-factor [perspective], the physical fitness benefits outweigh the possibility of hormone exposure from birth control or insect repellent,” said Cory Willis, a retired health inspector and current principal of Pool and Spa Education/Consulting in Anchorage, Alaska.

Frank Schiffman thinks it’s much ado about nothing. Even if the byproducts were found hazardous on some level, he said, it would be difficult to determine their effects because each situation is different.

“Mechanical and environmental factors, including filtration, turnover rates, evaporation, air handling, bather loads, water balance, and replenishment of water would be key influencers in the effect ... these products could have,” said the senior market manager of Axiall Corp., a pool treatments manufacturer in Atlanta. “It’s almost impossible to account for them.”

But Blatchley believes that further research could quantify the concentrations of these compounds in different pool settings, which may help uncover any lurking risks. For example, you’d likely find different types and amounts of pharmaceuticals in a university pool than you would in a pool designed for rehabilitation.

“From there, then we need to have conversations with people who are toxicologists or who work in the pharmaceutical industry on the human health side of things to see what their interpretation of this is in terms of the potential for effect on human health,” he said.
The impact of the findings could reach beyond pools and spas, Blatchley said. The researchers also hope to improve our understanding of how these compounds impact waste water, drinking water, and the broader environment.

“We really don’t pay much attention to what happens to [pharmaceuticals] after their intended application, and I think we really need to,” he said.