Dinoseb Banned as Herbicide; Danger to Workers Cited

Dinoseb, a herbicide that has been widely used by California farmers for 40 years, was banned Tuesday by the Environmental Protection Agency on the grounds that it possesses dangers of birth defects and sterility for farm workers.

“The ban is on all sales and use and is immediate,” said California Department of Food and Agriculture pesticide expert Rex Magee.

Dinoseb is used as a herbicide to kill weeds in a wide variety of crops and to dry up foliage on crops like potatoes before harvest, he explained.

Although the chemical has been used for decades, the dangers were not discovered until a West German manufacturer conducted new toxicological tests earlier this year, Magee said. The company notified EPA of the problem and shortly thereafter, both the EPA and the state Agriculture Department issued a warning that the product was not to be used by pregnant women while the test results were evaluated.

The EPA’s action banning the product was unusual. Normally, the use of a pesticide can be canceled only after a lengthy hearing process. However, EPA officials said the risk to workers exposed to Dinoseb is too great to allow its continued use, and they used emergency powers to order the immediate discontinuance. The ban is subject to appeal by farmers or manufacturers.

“Exposure during or shortly after field application poses a very serious risk of birth defects to the unborn children of pregnant women . . . and may also pose a risk of sterility for male workers,” said EPA Administrator Lee M. Thomas in a prepared statement.

Federal and state regulators report there is no hazard to consumers who eat produce treated with the chemical. The primary threat is to workers who apply the material, they said.

State Agriculture Department records show that 88 California workers have been poisoned while applying the chemical between 1981 and 1985. None of the California workers died, but the 1983 death of a farm worker in Texas was blamed on exposure to Dinoseb, EPA officials said.

Environmental groups hailed the banning of the 40-year-old chemical as a positive step.

“Dinoseb is bad stuff,” said the Natural Resource Defense Council’s Lawrie Mott. “EPA has finally acted correctly, in this country. But Dinoseb is still being used extensively in other parts of the world.”

Tuesday’s action caught the Western Agriculture Chemical Assn., a trade group of pesticide manufacturers, by surprise, according to Executive Director Elin Miller.

“This is news to us,” she said. “The farmers lose another tool.”

She declined further comment pending examination of the EPA order.

EPA records show that at least 80 companies are registered to manufacture and sell Dinoseb nationwide. Approximately 800,000 pounds of the material were used in California last year on potatoes, grape vineyards, alfalfa fields and 40 other crops.