That is what Conrad Daniel Volz, a researcher with the University of Pittsburgh Center for Environmental Oncology, is trying to determine.

He is heading up a study that is looking at contamination in area rivers.

Volz found mercury levels in Pittsburgh rivers remains moderate, but upriver in Kittaning, where fishermen say the water is cleaner, the mercury levels are the much higher.

new graph Volz said,” We have found mercury levels in fish from Kittaning is upwards of 19 times the level of mercury in fish in the Pittsburgh pool."

Another part of Volz's study focuses on estrogen levels in area water. He believes this is an even greater health concern than mercury.

Volz said researchers put fish extracts on human breast cancer cells and “the cancer cells have proliferated almost as much as mercury.”

According to Volz, 85 percent of fish tested from local water are sexless , “the cells don't look like they're male or female."

Volz believes the reason for that is too much estrogen in the rivers. He attributes the high levels of estrogen to cosmetics and cleaning products containing estrogen compounds being dumped down drains.

Volz recommends that people, especially if they have a family history of cancer, limit their intake of fish caught in the rivers to just one meal per month.

Volz believes what's happening with our fish is like a canary in the coal mine because they serve as a sentinel for human exposure to chemicals. It may explain what doctors are now finding in humans.

“It may be associated with human health effects. The proportion of male children being born is decreasing, there are more and more birth defects in boys."

People who eat the fish caught in the rivers should also be careful about how they cook their catch. Volz said the safest way to cook fish is to broil it, so the fat containing the contaminants drops below the fish.

University of Pittsburgh Environmental Oncology Center