Study investigates farm chemicals' role in decline of fertility

COLUMBIA, Mo. -- A University of Missouri research-er whose recent study suggested three common farm chemicals were linked to lower sperm counts and quality in mid-Missouri men is seeking a grant to determine whether the chemicals were spread through the water supply.

Shanna Swan, a professor of family and community medicine, said the idea that the herbicides alachlor and atrazine and the pesticide diazinon entered the men's bodies through the water supply was "the most plausible hypothesis, but certainly not the only one."

In November, Swan said a study showed fertile men from mid-Missouri's Boone County were found to have a lower mean sperm count and less vigorous sperm than men in New York, Minnesota and Los Angeles. The Boone County sperm also tended to be less vigorous.

In a follow-up study released last week, Swan said mid-Missouri men with low sperm counts showed significantly higher levels of the chemicals than Minneapolis males with better semen quality.

However, Dr. Stuart Howards, a leading urologist and male fertility expert at the University of Virginia School of Medicine, said few studies like Swan's turn out to be true.

Terry Timmons, an environmental specialist with the Missouri Department of Natural Resources public drinking water program, said drinking water from surface wells exceeded the maximum legal level of atrazine in 1994, resulting in 10 violations, Timmons said.

However, Timmons said, most of mid-Missouri's drinking water comes from ground water supplies and no traces of atrazine or alachlor have ever been present in Missouri ground water supplies.

"If we would detect a pesticide in any ground water system in Missouri, that would be man bites dog news," Timmons said.

Timmons suggested pesticide residue on food products or occupational exposure to the pesticides might have caused the results.

Timmons said people should not be scared to drink tap water.

University of Missouri biologist Fred vom Saal said the maximum amount of atrazine allowed by the government -- three parts per billion -- is too high. He claims even small amounts of atrazine have been shown to affect wildlife.

Bathing or showering in water contaminated by atrazine, vom Saal said, can be more harmful than drinking it.

Swan said she was not trying to attack the public water departments.

"I would like to work with the water utilities," she said. "We're all in this together."