NAAA Comments Again on Atrazine – Prior NAAA Comments Saved Aerial Application

Last week NAAA submitted comments on EPA’s updated mitigation proposal for atrazine. NAAA learned in the updated proposal that prior NAAA comments saved aerial applications of atrazine. The concerns over atrazine center around surface water runoff and its impact on aquatic organisms, not drift.

The registration review history of atrazine has been a series of decisions followed by reversals. Much of the back and forth has been around the aquatic level of concern (referred to as LOC or CE-LOC), which is the level of atrazine in water above which there are concerns for aquatic lifeforms. The lower the LOC, the more acres there are that are considered at risk from atrazine and thus subject to additional mitigations. Over the last 10 years the LOC has gone from 10 ppb, down to 3.4 ppb, up to 15 ppb, back to 3.4 again, and is now proposed to be set at 9.7 ppb.

NAAA comments echoed those of other agricultural groups, recommending that EPA use only sound science to determine the appropriate LOC. NAAA agreed with two additional mitigations prohibiting atrazine applications during rain or when soils are saturated. NAAA also agreed with EPA’s proposal to use the list of runoff/erosion mitigations from the herbicide strategy instead of a different list. NAAA did express concern over commercial applicators being responsible verifying grower compliance with runoff/erosion mitigation measures.