News

Use of Common Insecticides Might Be Restricted:
Organophosphates May Cause Health Risks

Aired May 17, 2000

The U.S. EPA is considering restricting one of the most widely-used group of insecticides. Organophosphates have been linked to memory loss, nervous system ailments, and other health problems. These compounds account for half of all pesticides sold in the U.S. and are used extensively in homes, schools, businesses, and agriculture. But while many people have pushed for tighter controls, some scientists feel the method of assessing the chemicals' effect is flawed. 90.3's Karen Schaefer has this report.

Karen Schaefer–In 1996, Congress passed the Food Quality Protection Act, which requires the federal EPA to review the amount of pesticides that may remain in food after it is grown. Among the first to be re-evaluated is a group of about 40 pesticides known as organophosphates. The active ingredient in many of these products is chlorpyrifos, a nerve agent that the U.S government approved for agricultural use in 1965. John Ward is a pesticide expert with the U.S. EPA district office in Chicago. He thinks the chemical poses a significant health risk.

John Ward– The organophosphate insecticide generally is more of an acute concern, which means they will have an immediate effect if inhaled or absorbed through the skin or certainly ingested. They can cause some immediate symptoms.

KS–Those can range from temporary flu-like symptoms to permanent nerve damage and even death. The EPA estimates that chlorpyrifos products account for a thousand accidental poisonings a year, most of them in people who are exposed to the pesticides in their own homes. David Shetlar is the Ohio Extension Service's state expert on pest control. He says homeowners are the people least educated in using pesticides safely.

David Shetlar–I think we certainly (need) to take a close look at what we allow homeowners especially to do. Frankly, I'm not worried about professionals–but with pesticides, who has to have any kind of training to walk down to any garden center and buy a jar of poison off the shelf?

KS–Some commercial pest control companies have already imposed their own bans on organophosphates. Orkin stopped using the chemical Dursban five years ago in homes and businesses. TrueGreen ChemLawn banned Dursban from its treatment of lawns and golf courses just this year. Some other uses of organophosphates–like mosquito control programs–have also been halted in favor of more environmentally-friendly products. But David Shetlar of the Ohio Extension Service is one of many scientists who's concerned about the way in which the cumulative effects of home and agricultural pesticides are being lumped together.

DS–The problem again is that when EPA puts all these things together, they say they're just going to lump them all together, they all have the same mode of action, we're going to put them all in the same risk cup. And what that means is that these pesticides are the common ones used in and around the home–these are the same pesticides that are often used in our food production. EPA says that's too much of these organophosphates and carbamates, and the risk or what we call the risk cup is filled up.

KS–Shetlar says that even though most people are exposed to the pesticides at home, farmers will have to cut back or even stop using organophosphates in order to reduce the cumulative effect. About 60 million pounds of the chemicals are used each year in field crops such as corn and in more limited quantities on fruits and vegetables. Shetlar argues that many small farmers can't afford to replace a once a year application of Dursban with three applications of a less harmful insecticide. John Ward says the U.S. EPA shares that concern.

JW–It's certainly one of the big concerns and one of the greatest impacts of the Food Quality Protection Act is going to be on minor crop producers and it's one of the things that both USDA as well as EPA have to take into consideration as these decisions are made. What we're trying to do is determine how do we come up with a strategy for phasing out of one chemical practice or one pest control practice into another that will sustain that grower's ability to produce that crop and still make it profitable for him.

KS–Ward and Shetlar agree there is now an array of safer insecticides that weren't available ten or twenty years ago. There are also new biological controls such as pheromones that have some agricultural applications. But Dr. Mary Garvin, a community ecologist with Oberlin College, says it will always be a race to stay one jump ahead of the bugs.

Mary Garvin–It's an evolutionary arms race. We try new things and the organisms adjust to those new things and that takes us on down the road to something else. And in some cases, we switch to biological controls, but again, that's an evolutionary arms race as well. And because of sexual reproduction and genetic variation, the target species adapts and it's an on-going problem.

KS–The U.S. EPA will announce its proposals on restricting organophosphate insecticides later this spring. But this is just the first group of pesticides to undergo reassessment. In all, the EPA must consider 469 other pesticide or high-hazard ingredients in nearly 10,000 food uses before August of 2006. In Cleveland, Karen Schaefer, 90.3 WCPN® 90.3 FM.