News Feature | July 2, 2015

Sex-Changing Fish Inspire New Method Of Wastewater Treatment

Sara Jerome

By Sara Jerome,

In an effort to target contaminants that affect the reproductive functions of fish, researchers have discovered a new way to remove traces of human birth control pills from municipal wastewater during treatment.

In a paper published in Scientific Reports, a research team helmed by Carnegie Mellon University Chemist Terrence Collins argues that a group of catalysts known as TAML activators “could be a viable option for large-scale water treatment,” according to a press statement from the journal. TAML activators are small molecules that behave much like oxidizing enzymes.

The study focused on the removal of 17alpha-ethinylestradiol (EE2), a synthetic estrogen found in oral contraceptives. The substance — which passes through the human body, into the wastewater system, and out into environmental waters — is problematic because it is linked to the feminization of fish. Male fish feminized by estrogenic contaminants have been found to create proteins responsible for the growth of eggs, which is not usually a male function, according to Oregon Public Broadcasting.

“Prolonged exposure to these female hormones can cause males to develop eggs in their testes and lead to the decline of fish populations,” the journal said.

Estrogenic contaminants may pose a threat to human males, as well. Water Online previously reported: “Something fishy is going on in the water, and not just with the fish. Recent research suggests that exposure to [pharmaceutical products] in drinking water may subject humans, particularly males, to gender-morphing and other reproductive system alterations.”

Here’s what the Scientific Reports study found when researchers tried to remove estrogenic contaminants using catalysts: “Our results provide a starting point for a future process in which tens of thousands of tonnes of wastewater could be treated per kilogram of catalyst. We suggest TAML/H2O2 is a worthy candidate for exploration as an environmentally compatible, versatile, method for removing EE2 and other pharmaceuticals from municipal wastewaters.”

It’s documented that drug particles move out of people’s bodies and into the sewage system, eventually winding up in the drinking water supply. Water Online reported: “It has long been known that there are trace amounts of PPCPs (pharmaceutical and personal care products) that escape our wastewater treatment plants and end up in waterways, including drinking water sources." U.S. regulators are considering whether to restrict PPCP levels.

Collins explained why combatting estrogenic contaminants is an important avenue of research.

"These chemicals, called micropollutants, can be bioactive at low environmentally relevant concentrations and are typically tough to break down," he said. "We need to get these micropollutants out of our water systems. Fish are indicators of what can happen when hormone control systems get hijacked by synthetic chemicals. We humans are also animals with endocrine systems, after all."

For more news about removing pollutants from wastewater, visit Water Online’s Contaminant Removal Solutions Center.