Scientific American: Pittsburgh Fish Make Breast Cancer Cells Grow

April 2007

Bringing Cancer to the Dinner Table: Breast Cancer Cells Grow Under Influence of Fish Flesh

Tests of river fish indicate their flesh carries enough estrogen-mimicking chemicals to cause breast cancer cells to grow By David Biello

Tests of fish caught in the rivers around Pittsburgh revealed that their flesh contains enough estrogen-mimicking chemicals to promote breast cancer growth.

Many streams, rivers and lakes already bear warning signs that the fish caught within them may contain dangerously high levels of mercury, which can cause brain damage. But, according to a new study, these fish may also be carrying enough chemicals that mimic the female hormone estrogen to cause breast cancer cells to grow. “Fish are really a sentinel, just like canaries in the coal mine 100 years ago,” says Conrad Volz, co-director of exposure assessment at the University of Pittsburgh Cancer Institute. “We need to pay attention to chemicals that are estrogenic in nature, because they find their way back into the water we all use.”

Volz and colleagues, including biochemist Patricia Eagon, took samples from 21 catfish and six white bass donated by local anglers as part of a study presented at the American Association for Cancer Research meeting in Los Angeles this week. The fish were caught in five places: a relatively unpolluted site 36 miles upstream from Pittsburgh on the Allegheny River; an industrial site on the Monongahela River; an Allegheny site downstream from several industries that release toxic chemicals; and the confluence of the Allegheny and Monongahela rivers, where Pittsburgh dumps much of its treated sewage and sewer outflows.

“This is the largest concentration of combined sewer outflows in the U.S.,” Volz notes, about the confluence, known as the Point. The researchers also bought several fish at the store as controls.