Waterways Supplying Birth Control To Fish

Fish are soaking up human birth control hormones, according to the latest research on how drugs transferred through waterways may affect wildlife.

"Flushed down toilets, poured down sinks and excreted in urine, a chemical component in the pill wafts into sewage systems and ends up in various waterways where it collects in fairly heavy doses. That's where fish soak it up," the Washington Post reported.

Trace amounts of pharmaceutical and personal care products (PPCPs) seep out of wastewater plants and end up in the water supply. PPCPs are unregulated, but the EPA has placed them on its Contaminant Candidate List (CCL), meaning it is monitoring whether regulatory action would be appropriate. PPCPs are only found in tiny concentrations in waterways, but research says they affect wildlife and possibly even humans.

New research by U.S. Geological Survey (USGS) scientists, published by Nature, supports the idea that PPCPs—and particularly, birth control hormones that seep into the environment—affect wildlife. The study focused on medaka fish.

The study found that "fish exposed to a synthetic hormone called 17a-ethinylestradiol, or EE2, produced offspring that struggled to fertilize eggs. The grandchildren of the originally exposed fish suffered a 30 percent decrease in their fertilization rate," the Post reported.

That could be dangerous for fish populations, according to the study. "These adverse outcomes may have negative impacts on populations of fish inhabiting contaminated aquatic environments," the study said.

Ramji Bhandari, a visiting scientist at USGS and the lead author of the study, put the research in context. "If those trends continued, the potential for declines in overall population numbers might be expected in future generations," Bhandari said, per the report.

Bhandari based the study on previous research in this arena, while testing for additional chemicals that may affect the fish.

"Bhandari expanded [the] experiment from past experiments by working with a chemical called BPA, which is used widely in plastics. The BPA had a similar effect on Japanese medaka fish used for the research," KBIA reported.

To view Water Online's in-depth coverage of PPCPs, click here.