This secret agent is orange - Agent Orange

The Vietnam War ended 20 years ago and President Clinton recently normalized relations with the nation's former enemy, but one of the conflict's most infamous agents continues covert operations on the American home front. The defoliant Agent Orange lingers on in hardware stores and farms across the country and, according to the National Cancer Institute, it may still be killing people.

As used in the Vietnam War, Agent Orange was a 50-50 mixture of two herbicides: 2,4,5-trichlorophenoxy-acetic acid (2,4,5-T) and 2,4-dichlorophenoxyacetic acid (2,4-D). Dropped by U.S. warplanes over Vietnamese rainforests, Agent Orange was effective in flushing Vietcong troops from their jungle hideouts.

But the toxic chemical felled more than vegetation; U.S. military personnel and Vietnamese civilians exposed to Agent Orange often developed serious medical problems. Postwar research established 2,4,5-T as the cause of soft-tissue sarcoma (a kind of malignant tumor), spontaneous abortions and numerous other ailments. Use of 2,4,5-T in the United States has been prohibited since 1983.

But Agent Orange's other half - 2,4-D - now appears in more than 60 agricultural herbicides and home garden products, including Weedone, Acme Vegetation Killer, and Scotts Lawn Weed Control. The most widely used herbicide in the world, 2,4-D ranks third among herbicides used in the United States.

Maybe it doesn't matter that thousands of Americans use 2,4-D products without knowing their connection to Agent Orange. But it is important to know whether it poses a health hazard to humans.

"Our epidemiologic studies show that 2,4-D is associated with an increased risk of [potentially fatal] non-Hodgkin's lymphoma," says Shelia Zahm, an epidemiologist at the National Cancer Institute (NCI). Zahm and her colleagues looked at patterns of the cancer and the use of 2,4-D in midwestern farmers.

Scientists have long been concerned about 2,4-D, and the Environmental Protection Agency (EPA) has required manufacturers of the weed killer to study its health effects. A 1993 Science Advisory Board review of 2,4-D data from many sources produced the scientific equivalent of a definite maybe: The board found insufficient evidence to establish a cause and effect relationship between 2,4-D and non-Hodgkin's lymphoma, but sufficient evidence to warrant further study.

Meanwhile, some former users have drawn their own conclusions: TruGreen-ChemLawn, the nation's largest lawn-care company, discontinued its purchase of 2,4-D products in 1986 out of concern for the health of its employees. But other businesses, farmers and weekend gardeners spend a whopping $180 million a year on the weed killer.

And the manufacturers and marketers of the product see no cause for alarm. According to Don Page, executive director of the coalition of 2,4-D producers that's conducting EPA-mandated testing, laboratory tests on animals have shown no 2,4-D toxicity. Page says other scientists have criticized the NCI study because some of its information came secondhand - from family members and associates of persons who had already died from non-Hodgkin's lymphoma.

But NCI's Zahm says the 2,4-D industry - which includes such well-heeled corporations as AGRO-GOR, DowElanco, Nufarm U.S.A. and Rhone-Poulenc - uses such criticism as part of a major public relations campaign designed to convince 2,4-D users that the product is safe. Meanwhile, the EPA is conducting yet another review of 2,4-D research, which could change 2,4-D's cancer classification to that of a "possible" or "probable" carcinogen, says EPA special review manager Jill Bloom.

Despite some worrisome evidence, Zahm refrains from calling for extreme action. "I don't think it's necessary to ban 2,4-D," she says. "It's not something that ends up in the food chain. The concern is to control exposure during application."

Right now there are no restrictions on the use of 2,4-D. Products containing the herbicide do come with EPA-mandated instructions for safe application, but Zahm worries that users don't read them. And home gardeners wearing shorts and T-shirts probably get a lot more exposure to the product than farmers who are using heavy machinery to spray their crops with it, she adds.

Among the questions about 2,4-D Zahm would like to see studied further: If a lawn is sprayed with 2,4-D, how much time must pass before it's safe for a child to play there?

Meanwhile, there's nothing printed on packages of 2,4-D products to tell consumers that what they're using to kill their weeds was once part of Agent Orange - or that the toxic work of that agent may not have ended with the Vietnam War.

(Maurice Martin is a Washington writer.)

COPYRIGHT 1995 Common Cause Magazine
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