Serious Questions Remain About EPA Atrazine Proposal

August 1, 2024

Growers received good news in early July when EPA proposed an increase in the atrazine aquatic level of concern (CE-LOC) from the ultra-low 3.4 parts per billion (ppb) level to a new level of 9.7 ppb. This announcement came on the heels of a Scientific Advisory Panel (SAP) for atrazine held last August. The Triazine Network, an alliance of grower organizations including IL Corn had requested the SAP last year and met with EPA in mid-July to discuss this latest proposal.

 

Now for the bad news. While the CE-LOC moved from 3.4 ppb to 9.7 ppb - nearly three times higher - the mitigation maps of impacted areas only minimally changed. EPA’s flawed mitigation maps and modeling would negate the positive impacts of the higher CE-LOC. Unfortunately, EPA continues to ignore 20 years of actual water monitoring data from states, and from its own programs.

 

Growers, through the Triazine Network, had also asked EPA to review two studies not included in the SAP. The worst of the two studies is extremely low quality and continues to significantly impact the atrazine CE-LOC. Because of the continued use of that flawed study, the CE-LOC remains under 10 parts per billion.

 

“The change in the CE-LOC is good, but if EPA continues to use the flawed modeling methodology resulting in bad mitigation maps, they null any progress made and fail to rely on sound science.” said IL Corn Growers Association President Dave Rylander. “It is a positive step that EPA appears to be open to taking our concerns into consideration before they release their final proposal."

 

EPA officials said they will open a comment period following the final atrazine proposal later this year.

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