Drugs In Miami River Could Be Changing Gender Of Fish And Frogs

BY JAMES STEINBAUER | Miami University Journalism Student

Particles of antibiotics, antidepressants, birth control, painkillers and a slurry of other pharmaceutical drugs are finding their way into southwest Ohio’s streams and rivers and they have scientists and environmental agencies in a regulatory quagmire.

Scientists say that some of these drugs could mutate the fish and amphibians they come in contact with, causing them to change gender.

In a study by the Miami Conservancy District, which monitors and analyzes water in the Great Miami River watershed, researchers found 17 different pharmaceutical compounds at 30 different testing sites. A previous study by the United States Geological Survey found more than six times as many.

This type of water pollution didn’t start in the chemical and paper companies that used to pepper the Great Miami river from Dayton to Hamilton.

It started in your bathroom.

"It’s us. Everything we take," said Mike Ekberg, a researcher at The Miami Conservancy District. "If you take ibuprofen, your body is going to metabolize some of it, but a lot of it will move through the body un-metabolized. You'll pee it out and it will enter into the sewage system."

Pharmaceutical and personal care products, or P.P.C.P.’s, are being flushed into the Great Miami from wastewater treatment plants or leaching into groundwater from old septic tanks.

Researchers call these particles “emerging contaminants.” That’s not because they’re new — they’ve been in our waterways for decades. However, the technology needed to detect P.P.C.P’s has improved and scientists can now locate them at very small levels.

“When we get down to those smaller levels, it’s like, ‘Wow, there’s more things in here than we ever imagined,’” Ekberg said. “My gut feeling is that pretty much anything people are taking is making it’s way into the water. If you know what to look for, you can find it.”

Chemical Cocktails

Scientists don’t yet know the ultimate ecological impact of this chemical cocktail. There is little evidence that traces of P.P.C.P.’s are harmful to humans, but one specific group of chemicals, called endocrine disruptors, can cause mutations in wildlife.

“I think were really only scratching the surface right now in terms of what the known effects are, but a lot of the concern is about reproductive function,” said Ty Hoskins, a Ph.D. candidate at Miami studying how endocrine disrupting chemicals influence reproductive organs in developing frogs.

In the absence of an endocrine disruptor, Hoskins said, an individual may have become a male. However, increased levels of estrogens from birth control and other endocrine disrupting chemicals in the water are messing up that natural process.

Endocrine disruptors are causing some fish and amphibians to change their gender.

A USGS study found that some native fish populations living downstream from wastewater treatment plants were found to exhibit similar endocrine disruption, including low male-to-female sex ratios and fish that have both male and female reproductive organs.

Near Impossible Regulation

And one problem with endocrine disruptors, Hoskins said, is that they’re almost impossible to regulate.

Until now, environmental agencies and regulators have been working off an adage coined in the early 1500s by the “father of toxicology,” Paracelsus — the dose makes the poison.

The traditional logic states that the higher the dose, the more toxic the chemical.

“That’s the way our whole regulatory system is designed,” Hoskins said. “But endocrine disruptors do not always show traditional dose response relationships. For example, they can be toxic at very low concentrations and less toxic at higher concentrations. How do you deal with a chemical like that?”

The World Health Organization has labeled more than 800 endocrine disrupting chemicals and the federal government currently does not regulate any of them.

“Under our current way of doing things, it takes a really long time to develop a maximum contaminant level for some compounds,” Ekberg said. “And people are creating new types of drugs every year. The regulatory process can’t keep up.”

An American Bullfrog basks in the sun at Bachelor Pond on Miami's Trails and Natural Areas. Scientists say endocrine disrupting chemicals, like birth control, are finding their way into Ohio's streams and rivers and mutating amphibians and fish. -- Photo by James Steinbauer