A coalition of farm groups is trying to scuttle a proposal from the U.S. Environmental Protection Agency that would increase restrictions on the herbicide atrazine.
Some research indicates that atrazine could be more dangerous at low levels than previously thought, with links to birth defects and cancer.
The American Farm Bureau Federation argues that lowering allowable levels of atrazine would hurt the environment – because it’s needed for so-called conservation tillage, where farmers plow the previous year’s crop residue, like corn stalks or wheat stubble, into the fields to prevent soil erosion and runoff.
But environmental groups have long been pushing for a ban on the weed killer.
Atrazine in runoff has been linked to other environmental damage, like stunted development and disrupted hormones in animals.
The EPA has not evaluated the chemical since the last time it was up for review in 2003.
Public comment on the proposed atrazine risk assessment closed on Wednesday this week.
Another report is due out later this year that will focus on atrazine’s effect on human health.