If you live in central Illinois, you may have spotted a small, dome-like device that resembles a flying saucer along a fence or in a neighbor’s backyard. Those devices are air samplers, specifically designed to measure pesticide drift. We’ve placed four samplers in agricultural communities to learn more about what chemicals, if any, might be drifting from corn and soybean fields onto nearby backyards, school grounds and parks as spraying gets underway this spring. We have also placed a sampler near our office in Champaign to serve as a control.

Below, you will find more information about how this project will contribute to our reporting, how the community helped determine the locations of the samplers and exactly how the samplers work.

If you have any questions, comments or want to learn more, don’t hesitate to email staff@investigatemidwest.org or call 217-239-6617.

Why measure pesticide drift?

According to the EPA, pesticide drift can pose health risks to people “when sprays and dusts are carried by the wind and deposited on other areas.” Those other areas include schools, backyards, public parks and playgrounds.

Approximately 229.3 million pounds of pesticides were applied to corn in the U.S. in 2016 and 155.4 million pounds of pesticides were applied to soybeans in 2015, according to the most recently available data from the USDA.

When it comes to pesticide spraying in the Midwest, the product label is the law, and the labels are meant to lower the risk of drift. Some pesticides are also restricted-use, meaning only someone with a special certification can handle or apply them.

But as we reported about the herbicide dicamba last season, sometimes pesticides can move off target in ways applicators and regulators didn’t predict.

Other states have taken additional steps to protect people against possible drift from agricultural chemicals. Alabama, Arizona, California, Louisiana, Maine, Massachusetts, North Carolina, New Hampshire and New Jersey have restrictions beyond the label when it comes to spraying near schools. We reported on those laws in a story published earlier this year.

How were the sites for the air samplers determined?

We asked for your help. In March, we posted a call on our social media channels and sent a message to our newsletter subscribers asking where community members wanted to see the air samplers go up.

We prioritized schools that were interested in hosting air samplers because experts, including the American Academy of Pediatrics, say children can be more susceptible to the effects of pesticides. And because the Midwest does not have additional laws about pesticide spraying near sensitive areas such as schools, we were interested in learning more about whether this might be putting people at risk.

We made dozens of calls to Parent Teacher Associations, scout troops, superintendents, school administrators and others in the area. In the end, we had two rural schools – one in Tuscola and one in Bismarck – say they were interested in being part of the project.

We also received several messages from local homeowners who offered to host an air sampler. In addition to the schools, we decided that a home in Sidney and a public park in the rural town of Sadorus, both surrounded by agricultural fields, would be good locations.

How do the air samplers work?

Outdoor passive air samplers are designed specifically to trap pesticides onto a polyurethane foam (PUF) disk inside. The dome shape of the device keeps the PUF safe from sunlight, rain and other environmental elements that could dissolve any chemicals that collect there. The sampler is small, portable and does not require electricity or batteries. After about four weeks, we will collect the samplers and PUF disks from the five sites to have them professionally analyzed at a laboratory.

Because of the way the analysis works, if we want to test for glyphosate (one of the most commonly used herbicides) we will not be able to test for the other chemicals on the same foam disk. The analysis for 2-4-D and dicamba, on the other hand, can be done together on one disk. We’ll talk with the community members who hosted our samplers to see which pesticides they are more curious about.

What will we do with the results?

The results will give us a basic understanding of how many feet agricultural chemicals such as glyphosate, 2-4-D and dicamba are drifting from the field.

We will share our results in a story that includes interviews with experts as well as parents, residents and pesticide applicators in the communities that hosted the samplers. You can also share your experience with us by submitting this form.