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Battle Looms on Chemicals That Disrupt Hormones : Science: Research finds threats at levels once thought safe. Cleanup of DDT off Palos Verdes is part of debate.

THE GENDER WARP. Are chemicals blurring sexual identities? Last in a series

October 04, 1994|MARLA CONE | TIMES ENVIRONMENTAL WRITER

WAUKEGAN, Ill. — After waiting nearly two decades to cleanse their lake-shore harbor of a million pounds of toxic waste, the people of this working-class suburb of Chicago were ready to party.

Setting sail on Lake Michigan aboard a cruise ship aptly named Celebration, local, state and federal dignitaries proclaimed the elaborate $21-million cleanup of Waukegan Harbor officially complete this summer. The marina--for years stigmatized as the PCB contamination capital of the world--was declared safe for everyone who works and plays there.

But the celebration may have come too soon.

Compelling new scientific evidence has emerged indicating that low concentrations of pesticides and industrial chemicals once thought to be harmless can alter the hormones of wild animals, confusing their sexual identities and rendering them infertile.

The threat from these decades-old chemicals--most notably massive amounts of polychlorinated biphenyls (PCBs) in the Great Lakes and DDT off the shore of Los Angeles--has stoked a long-smoldering environmental debate: How clean is clean?

For years, how much pollution to remove from severely contaminated spots has been based largely on a single target--reducing the cancer risk to humans. But that may not be enough to defend bald eagles, trout, alligators and other animals from chemicals that imitate estrogen or block testosterone in the womb. Humans who eat contaminated fish and other food harvested from these areas also could be passing subtle reproductive problems such as low sperm counts to their children.

"In spite of government regulations and testing--which we all thought was adequate in all honesty--we are now finding effects that are much more subtle and much more intergenerational than we thought," said Tim Gross, a University of Florida endocrinologist who discovered part-male, part-female alligators and turtles in a Florida lake contaminated with DDT from a 1980 spill.

The concern over environmental hormones comes at a crucial time. In Southern California, federal officials are grappling with how to eliminate--or more likely contain--4 million pounds of the pesticide DDT dumped several decades ago in ocean waters off the Palos Verdes Peninsula.

Nationally, dozens of waterways from Washington's Puget Sound to South Florida's canals remain polluted with PCBs, compounds used as industrial insulators and lubricators, or DDT, even though they were banned in the United States in the 1970s.

"We have to address this enormous legacy," said Michael Gilbertson, a biologist with the International Joint Commission, a U.S.-Canadian government panel helping guide cleanup of the Great Lakes. "How are we going to come to terms with all these dump sites? What this work on estrogens shows us is we have a very long way to go."

Eliminating the potential for hormone-like effects is shaping up to be a political struggle.

The cost of even a basic cleanup job runs in the tens of millions of dollars and the projects take years. Expanding the scope to tackle lower concentrations of chemicals would push the price up and take even more time. Beyond that, raising new health and ecological concerns could cast a pall on a community's businesses and recreation, especially sport fishing.

"It's a legitimate question to ask how much it is going to cost and what are the benefits," said John McCarthy, vice president for science and regulatory affairs at the American Crop Protection Assn., which represents Dow, Monsanto and other major pesticide producers. "I know it's not popular to talk about economics when you're talking about health risks, but you've got to get real too."

Dealing with the legacies of the past, however, is only one contentious aspect of the battle emerging over environmental hormones.

To avoid saddling future generations with new problems, the U.S. Environmental Protection Agency and the chemical industry are wrestling with whether to restrict some of today's chemicals. About 25 popular insecticides, herbicides and fungicides--applied on millions of acres every year in the United States--have been shown in laboratory tests to imitate estrogen or inhibit testosterone.

Included are many pesticides, such as atrazine, endosulfan, EBDCs, parathion and dicofol, that help farmers protect and grow bountiful harvests of fruits, vegetables, grains and other crops worth billions of dollars annually. Some also are widely used for eliminating garden pests and weeds.

Seven industrial compounds--such as nonylphenol, used in plastics and detergents; styrene, an ingredient of rubber; and dioxins, a widely dispersed pollutant from paper mills and other manufacturing plants--are suspected of causing problems as well.

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