UNL team looking into a potentially dangerous herbicide used in Nebraska
LINCOLN, Neb. (KLKN) — Researchers from the University of Nebraska-Lincoln are studying how our climate impacts the spread of a popular herbicide that’s potentially dangerous to both wildlife and humans.
Atrazine is one of the most commonly used herbicides in the U.S. right now.
It is good at controlling weeds, which helps farms maximize yields of corn.
But a previous study found that Nebraska counties that used it the most between 1995 and 2014 had higher rates of estrogen-related cancers, including breast cancer. Clusters of prostate cancer were also found.
Exposure to herbicides often comes through drinking water, which is drawn from groundwater.
Yusong Li, a UNL civil engineering associate professor, said 90% of rural Nebraska areas are using groundwater as their main source of drinking water.
That’s where UNL researchers step in.
“Atrazine is already a concern,” Li said. “People in environmental engineering and agriculture, people started to really care about it. The EPA, the Environmental Protection Agency, already set a maximum concentration level for atrazine at 3 milligrams a liter, so it is already a concern.”
The team wants to predict future climate changes that could impact the soil’s ability to absorb or filter some of the herbicide before it reaches the groundwater. Faster erosion of the soil due to heavy precipitation can lead to higher accumulations of atrazine in the water.
“Those rates, they are controlling in how herbicides can migrate and accumulate in the subsurface,” said Chuyang Liu, a water resource engineering Ph.D. student. “So, maybe we should think about some technology and methods to control those rates, then we can control the accumulation leading into the groundwater.”
After running thousands of simulations, the researchers found that pockets of high atrazine concentrations have the potential to move closer to our groundwater table, depending on precipitation.
Soils with little bacteria or little organic matter won’t be able to absorb as much of the herbicide.
“In those areas, climate variability will have a huge impact,” Li said. “When you have higher precipitation and more rainfall, it will essentially push it down much quicker.”
The UNL team will be working to better model how heavy rain trends could push atrazine farther into the soil faster, affecting more of the groundwater. To do this, it will study how quickly atrazine degrades, and what influences those rates.