Pollution-Busters Hit The Q

Estrogen, fertilizers, plastic and heavy metals may kill entire species of fish in the Quinnipiac River — and limit humans’ dinner and recreation options. Unless four University of New Haven researchers succeed in sounding the alarm.

The four UNH researchers are testing the levels of a few pollutants along various sites of the 38-mile river, to find their sources and inform policy to reduce them.

Though the chemicals are not immediately harmful to humans, they could drastically change an ecosystem locals use for food, travel and recreation.

The Quinnipiac River’s water quality has improved in the last three or four decades. For more than a century, factories dumped their heavy metals and homes flushed their sewage waste into the river, killing most of the fish and oysters that once thrived there. Some of that historical pollution remains in the water.

And new sources of pollution are being swept into the water daily.

“If you find out where they’re coming from, you’re more able to stop it,” said John Kelly, one of the UNH researchers.

Kelly studies two species of fish — mummichog and longnose dace — for signs of estrogen, a hormone found in birth control products that is not being properly filtered out of the waste system. Kelly searches for ​“feminized” male fish, which will have specific proteins or genes ​“that should never be present in males,” he said.

The concentration of estrogen is likely too low in the Quinnipiac to affect humans. But it can be catastrophic for the foraging fish Kelly studies, decreasing their fertility and taking away a major source of food for fish species higher up in the food chain, he said.

The proteins allow him to quantify the amount of estrogen present in that part of the river, he said.

His colleague Melanie Eldridge is using a different method to track the same chemical. She adds bioluminescent yeast to water samples, causing the water to light up when traces of estrogen are present. The brighter the glow, the more estrogen is present — allowing her to quantify the amount, she said.

Traces of heavy metal are vestiges from a century or more of lax environmental regulation on industry. Since March, Amy Carlile and Jean-Paul Simjouw have been taking samples of algae and using radiation to detect whether the section of the river contains copper — which can wipe out parts of the ecosystem.

The lowest link in the food chain, algae are ​“bioindicators of stream health,” Carlile said. If they’re not doing well, the river isn’t doing well.

Ultimately, the algae could be used to fix the problem — if they can take in the excess copper in the water, scientists can harvest the algae to more easily remove the metal, Carlile said.

All three projects are funded by the Quinnipiac River Fund, which collaborates with community organizations to restore the river’s health.