Intersex fish may be linked to runoff

    Researchers have found fish with both male and female characteristics in lakes in the Delmarva peninsula.

    The male largemouth bass carrying eggs were found in six Delaware and Maryland lakes. It’s not a new phenomenom — similar intersex fish have been found in the Potomac and Susquehanna rivers and nine watersheds around the country. But scientists still don’t know what kind of pollutant is causing the mutations.

    Dan Fischer is the research scientist with the University of Maryland who found the fish.

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    “We’re still in the infancy of trying to figure all this stuff out, but the fact that a male fish has eggs in its gonads is not a natural occurrence,” he said.

    Fischer says waste from humans and poultry, as well as a host of other pollutants, can cause the hormonal disruptions leading to the mutation. Scientists are still studying how the mutations affect the health and reproduction of the fish, and what the implications are for human health.


    Shelly Vineyard, a toxics specialist with the advocacy group Environment America says that’s the most worrisome part.

    “It’s a really big concern to see that our fish are so impacted by the chemicals that we’re pouring into our waterways,” she said. “If they’re making our fish intersex we can only imagine what they might be doing to our own bodies.”

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