"Two neonicotinoid insecticides - acetamiprid and imidacloprid - may affect the developing human nervous system, said the European Food Safety Authority (EFSA)." That was the recent press release from EFSA, reported in The Guardian here.
In making its statement, EFSA considered a number of scientific studies from laboratory cells and test rodents, ultimately recommending reducing the allowable exposure limits of the pesticides. The acute reference dose - considered to be without appreciable risk over a lifetime of daily ingestion - should be cut by three-quarters for acetamiprid, and by a quarter for imidacloprid. Good for EFSA, for putting the protection of human health above Big Ag's interest in selling more toxic pesticide!
Imidacloprid was first approved by U.S. EPA in 1994, and it's human health risks were reviewed again in 2007. EPA's review included a 2001 Developmental Neurotoxicity Test (DNT) submitted by the manufacturer, Bayer Corporation, which is designed to examine pesticide impacts on brain structure and function when exposures occur during fetal development. However, EPA determined that Bayer's DNT study did not fulfill the guideline requirements, due to serious flaws in the study design including incomplete data reporting and inadequate positive controls.(See NRDC's comments in 2009 to EPA on this issue here at EPA-HQ-OPP-2008-0772-0005).
Nonetheless, EPA determined that there were no health risks of concern from continued residential uses, including on domestic pets, residential lawns, golf courses, and residential ornamental plants where children and pregnant women may be exposed. (See Document No. EPA-HQ-OPP-2008-0844).
Worse, EPA reduced the safety factor required by the Food Quality Protection Act (FQPA). (See EPA's data summary and FQPA determinations for imidacloprid here). The FQPA safety factor is meant to provide an additional measure of protection for infants and children that are exposed to pesticides.
In 2006 a report of the U.S. Office of the Inspector General recognized that testing pesticides for their risk to the developing brain and nervous system was a critical component of improving data quality and ultimately protecting children's health from pesticides. We agree!
The U.S. EPA should be routinely requiring robust, reliable, properly-conducted developmental neurotoxicity tests, including learning, memory, and behavior data, to accompany all pesticide registrations where children or pregnant women may be exposed. And, they should start with the neonicotinoid pesticides!
For more about the failures and weaknesses in our nation's pesticide registration process, see my blog here.