March 19, 2009
Pesticide mixes face added scrutiny
Further restrictions are up the Environmental Protection Agency
Heather Hansen, executive director, Washington Friends of Farms & Forests Olympia, Wash.
Click Here or scroll down for Cookson Beecher's response
As some of you will recall, the first week of March, there was a news story carried across the country about new pesticide research by NOAA Fisheries and WSU that appeared to show that combinations of pesticides could be more harmful to salmon than the effects of each individual product added together. Several aspects of the study were reported in such a way as to imply that the legal use of pesticides is causing more harm than that data actually shows. Below is my letter to the Capital Press about the first story they ran on the subject. Below that is another story that repeats most of the first article.
One more note on the subject, a similar story ran in WSU’s College of Ag e-newsletter, “On Solid Ground” on March 4. Dean Bernardo was away on travel at the time and did not have an opportunity to review the edition before it went out. Excerpts from his comments to me about the issue include, “Because of the controversial nature and complexity of this research, “On Solid Ground” was clearly not the appropriate medium to report findings from this work. Dr. John Stark is an excellent eco-toxicologist who has published numerous scientific papers and is competitive for funding at the national level. This research was specifically motivated to gain a better understanding of the neurotoxicity of combinations of insecticides on aquatic species – a worthy and fundamental research objective.” For those interested in learning more about the study, the full article is available at: http://www.ehponline.org/members/2008/0800096/0800096.pdf
LETTERS TO THE EDITOR
Pesticide study ignores reality
The March 5 AP story titled, "Pesticide cocktails prove extra-deadly to salmon, researchers at NOAA and Washington State University design tests to reflect real-world situation" was misleading on several counts. There have been no fish kills from legal use of the products studied. The levels used in the research study were nearly 1,000 times higher than any detection in Washington waters. In no way does that reflect the "real-world." Three of the products studied have had significant label changes in recent years. They are no longer available to homeowners and are used less often in agriculture.
The study states that synergism between pesticides is more likely to occur at higher concentrations. Given that the actual levels detected in water are 1,000 less than what was studied, this data has no relevance to the real world.
The study assumes that two or more of the specific pesticides studied will occur in high levels at the same time and place. In Washington, it is not common to use these products at the same time of year. We believe it would be rare for combinations to occur at the same time and place.
Salmonids generally live in rapidly moving water. Pesticide occurrences would be in pulses where the exposure is for a short time. The exposures in this study were maintained for four days. Once again, this does not reflect the real world.
Research at other universities shows no effects on salmon from a mixture of 10 different pesticides including several of the ones in this study when tested at levels actually found in streams. When real-world data is used, so far the results show no effect on salmon.
The Washington State Department of Agriculture has been monitoring surface water during peak pesticide usage times since 2003. They have specifically looked for products thought to be of concern for salmon. Their data shows that our growers are careful to use products according to label directions.
The next time the headlines say "real world" I hope there is more connection to reality.
Heather Hansen, executive director, Washington Friends of Farms & Forests Olympia, Wash.
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March 19th, 2009
Cookson Beecher, Capital Press
A recently released study revealing that pesticides can be even more harmful to juvenile fish when they combine with other pesticides raises questions about possible future restrictions on some agricultural pesticides.
However, a spokesperson for an industry trade group said the study didn't reflect "real-world situations" and doubts whether it will ultimately result in changes in how farmers use the pesticides.
The research, conducted by Washington State University and NOAA Fisheries, focused on five organophosphate and carbamate pesticides: diazinon, malathion, chlorpyrifos, carbaryl and carbofuran, all of which are commonly used in California and the Pacific Northwest.
According to various studies done by federal agencies, these chemicals are frequently detected in waterways that provide habitat for threatened and endangered species of West Coast Pacific salmon.
In an interview with Capital Press, John Stark, one of the study's co-authors and director of WSU's salmon toxicology research lab at Puyallup, said the researchers had expected to find that the pesticide combinations had an effect on the nervous systems of juvenile salmon and other marine life but hadn't expected that they would be more harmful than the sum of a mixture's parts.
"We were pretty surprised at that," Stark said. "We had to make sure about what was really causing the harmful effects. But we do know that fish are exposed to a soup of pesticides.
The research focused on mixtures of two pesticides at a time.
Although some of the research involved high doses, Stark said that some of the experiments were realistic about what's actually in the water.
When considering what this study - and subsequent studies on other pesticide combinations - will have on future pesticide registration decisions, Stark said that will be up to the federal Environmental Protection Agency.
"When information like this comes out, the fisheries services consult with the EPA," Stark said.
Susan Helmick, spokesperson for pesticide industry trade group CropLife America, said that the results or recommendations of the recent study won't affect farmers' ability to apply pesticides in the short term.
"This growing season should not be affected," she said.
She also said that the study has "no relevance to real-world situations."
"If EPA uses sound science, this shouldn't be a problem," she said, referring to the study.
Stark, meanwhile, said that various studies have shown that a lot of pesticides found in waterways are coming from suburban and urban areas.
"Farmers are usually very good stewards," he said. "They take classes and have to be licensed to be pesticide applicators. They lose money when they overapply or misapply pesticides."
The results of the recent WSU-NOAA Fisheries study were published in the March edition of the journal Environmental Health Perspectives.
In an e-mail to Capital Press, EPA spokesman Dale Kemery said EPA is currently reviewing the study's summary to understand its methodology and results.
"This review will help us determine whether the study might be instructive for our assessment of other organophosphate and N-methyl carbamate pesticides, and whether the results have applicability for other classes of pesticides," Kemery wrote.
Jim Lecky, director of NOAA Fisheries' Office of Protected Resources, told Capital Press that NOAA Fisheries considered the effect of combinations of pesticides on threatened and endangered fish when it drew up its biological opinion last year on three pesticides - diazinon, malathion and chlorpyrifos.
According to that opinion, the three pesticides can be harmful to West Coast Pacific salmon.
"I would hope EPA will incorporate pesticide mixtures into their registration process," Lecky said. "That's where we'd like EPA to be."
Nathaniel Scholz, co-author of the study and NOAA Fisheries research zoologist at the agency's Northwest Fisheries Science Center, told an AP reporter that new research needs to be designed that takes into effect the "real-world" situation when pesticides almost always coincide with other pesticides.
NOAA Fisheries is currently reviewing carbaryl, carbofuran, and methomyl, as part of court-ordered review of 37 pesticides that could be harmful or lethal to salmon and steelhead in California and the Pacific Northwest. The opinion is expected to be released in April.
