Clean Water: The Next Act - Emerging Contaminants Feminizing Puget Sound Fish
When the Clean Water Act was created 40 years ago rivers were on fire and raw sewage was spilling into some waterways. The Act has accomplished a lot over the years - reining in the largest industrial polluters and improving water quality, overall.
But there are some emerging contaminants the Clean Water Act was never designed to control, and they are affecting the environment in new and different ways. Ashley Ahearn has the latest installment in our ongoing EarthFix series “Clean Water: The Next Act."
Scientists first noticed something fishy going on in Puget Sound about 10 years ago.
Lyndal Johnson is a fisheries biologist and toxicologist with the National Oceanic and Atmospheric Administration. She and a team of scientists were out sampling English Sole – a flatfish that is common here.
Johnson: “And this was when we noticed these fish in Elliot Bay, when all the other fish had completed spawning, ready to go home, it’s all over for them, the Elliot Bay were still ripe and still had eggs that they had not yet spawned.”
The team went back and sampled more fish around Puget Sound and found even creepier results. Some male fish were producing a protein called vitellogenin.
West: “You don’t want to see that in males.”
That’s Jim West, a senior scientist with the Washington Department of Fish and Wildlife. He was out on the water with Lyndal Johnson when they found the weird fish. Vitellogenin is a protein used to make egg yolks, so you find it in mature females, but never in males.
West: “It’s an indication that they’ve been exposed to something, some chemical, that is essentially feminizing them.”
These fish weren’t dying. From the outside, they didn’t even look different. But there were striking changes going on inside them.
The team took more samples. The results: almost half of the 49 male English sole they tested on the Seattle waterfront were producing the female egg yolk protein.
The researchers found similar results in the juvenile Chinook salmon they tested at that site.
But the fish here are not alone. The US Geological Survey collected bass from more than 100 rivers around the country. One-third of those fish showed signs of feminization and intersex characteristics.
Don Tillitt is a toxicologist with the USGS in Columbia, Missouri.
Tillitt: “Mainly what we saw were testicular oocytes in what would otherwise be normal testicular tissues.”
Ahearn: “Testes with eggs in them.”
Tillitt: “Testes with eggs in them, exactly.”
Pinpointing the exact chemicals that are causing this feminization and intersex development has been the biggest challenge for scientists so far. But many believe a group of chemicals known as endocrine disruptors are to blame.
They’re sort of like hormone imposters. They act like natural hormones – estrogen or testosterone for example – and mess with the body’s natural hormonal messaging system.
Bisphenol A is probably the most well-known chemical in this family. You’ll find it in certain plastics, the liners of canned goods, epoxies – even kids toys.
Synthetic estrogen from birth control pills has also been shown to feminize fish.
These chemicals get into our bodies and then end up in wastewater. Tillit says that wastewater, even though it’s been treated, carries some of the chemicals into nearby waterways.
Tillitt: “So it’s not surprising that in certain locations, downstream from wastewater treatment plants are some of the most common locations where we can find intersex.”
The problem is: even the most modern wastewater treatment facilities aren’t specifically designed to remove this new class of chemicals.
Tillitt says regulation and treatment systems are going to have to adapt to manage endocrine disrupting chemicals, though it won’t be easy or cheap.
Environmental agencies here have known about these chemicals and their impacts on animals since the 90s.
Redman: “We recognize this is a problem but we don’t have it under control.”
Scott Redman is a senior science program specialist with the Puget Sound Partnership. The partnership has listed endocrine disrupting chemicals as a threat to Puget Sound and says they will eliminate the harm to fish by 2020. But their plan of attack is somewhat hazy.
Redman: “So we have efforts to control stormwater and improve wastewater, those we think will help but we may need more targeted efforts to the specific chemicals that are causing this harm and we’re just, we haven’t grappled with what those specific actions may be.”
A major national health study found Bisphenol A in the urine of more than 90 percent of Americans. It’s also prevalent in stormwater samples collected in King County.
After years of debate the federal government banned the use of bisphenol A in baby bottles and sippy cups this summer. It’s too soon to say if that ban has had any effect.
Jim West with the Washington Department of Fish and Wildlife says these new chemicals present challenges that the creators of the Clean Water Act could never have seen coming. And that calls for strong action and fresh thinking.
West: “I like to say that the fish are telling us what the problems are, if we’re out there looking.”
Copyright 2012 Northwest Public Radio