Report: Research links pesticide use to cancer rates in farm states
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A growing number of researchers, doctors and farmers say pesticides may be contributing to cancer rates, according to a new investigation by nonprofit Investigate Midwest.
Why it matters: Iowa has the nation's second-highest cancer rate and is a heavy-pesticide state, using 53 million pounds last year, per Investigate Midwest.
What they're saying: "Iowa doesn't really stand out dramatically" in typical cancer risk factors like obesity or tobacco use, Richard Deming, medical director at MercyOne Cancer Center in Des Moines, told Investigate Midwest.
- "But one thing that distinguishes Iowa from other states is our environmental exposure to agricultural chemicals."
State of play: Investigate Midwest's analysis of federal data from the U.S. Geological Survey and National Cancer Institute found that 60% of the 500 counties with the highest pesticide use also had cancer rates above the national average.
Zoom in: A direct link between pesticides and cancer is difficult to establish, as cancer can take decades to develop.
- But overlaying a map of cancer rates and the nation's top crop-growing regions, where pesticide use is highest, shows the highest disease rates.
- Lead corn growers like Iowa, Illinois, Nebraska and Missouri had the highest cancer rates, as well as fruit-growing states like California and Florida.
The big picture: Bayer, the company that produces Roundup, a glyphosate-based pesticide, has been under scrutiny for years and has faced thousands of lawsuits from people saying its product failed to warn users about cancer risks.
- "This is one of the most transparently reviewed products ever," Jessica Christiansen, the head of crop science communications for Bayer, told Investigate Midwest. "This product is so well studied … been on the market for over 50 years with thousands and thousands of studies. There is no linkage to cancer, there just isn't."
Zoom out: As pesticide companies face increasing scrutiny, at least six states, including Iowa, are considering bills that shield pesticide makers from certain lawsuits.
- The bill is still alive this year. Over 100 people protested it last week at the Statehouse, calling it a "Cancer Gag Act," per IPR.
The latest: Last week, President Trump signed an executive order demanding an increase in the supply of glyphosate-based herbicides in the U.S., saying it was a matter of national defense and food-supply security.
- Meanwhile, Bayer has agreed to a $7.25 billion deal to settle tens of thousands of lawsuits that its weedkiller Roundup caused cancer.
What we're watching: A Supreme Court ruling is expected this summer regarding whether Roundup can stay in American stores.
