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California Halts Consideration of New Uses of Neonicotinoids in the State

By Aimée Code on 8. January 2018
Aimée Code

Effective immediately, the California Department of Pesticide Regulation will not consider applications for any new uses of a class of neonicotinoid insecticides that includes the most widely used neonicotinoids.

California has just taken a positive step for pollinators, aquatic organisms, and all of us that rely on these important invertebrates. This week the California Department of Pesticide Regulation announced that, effective immediately, DPR will not consider applications for any new uses of a class of neonicotinoid insecticides that includes imidacloprid, thiamethoxam, clothianidin and dinotefuran—until re-evaluations of the chemicals are completed.

The risk of neonicotinoids to pollinator declines and aquatic ecosystems is well documented. A recent Xerces review of California’s water quality monitoring data revealed significant concerns. Our findings demonstrate that the frequent occurrence of harmful contamination levels in California’s rivers and streams could be killing sensitive aquatic invertebrates, leading to far-reaching effects on aquatic ecosystems and the broader environment.


According to 2015 Pesticide Use Reports from DPR, grapes, citrus, tomatoes, lettuce, and pistachios round out the top 5 crops on which the neonicotionoid imidicloprid are used. Neonicotinoids are frequently found in California rivers and streams at levels that are known to harm aquatic invertebrates. (Photo:


Unfortunately, at the federal level, the US Environmental Protection Agency is taking a very different approach to neonicotinoids. Last month, in conflict with an Obama era prohibition on allowing any additional registrations of neonicotinoids, EPA announced it would consider allowing the use of thiamethoxam, a long-lived neonicotinoid known to be highly toxic to bees, to be used across on 165 million acres of crops across the US. This is an area roughly the size of Texas.

In the face of the federal backsliding, California’s announcement demonstrates a positive step forward but there is still a lot more the state needs to do to address the threats these highly toxic, highly persistent insecticides pose to the environment.  The Xerces Society is actively working to prompt California to initiate efforts to better protect its invaluable natural resources from existing neonicotinoid contamination.


Further Reading

Understanding Neonicotinoids.

Learn more about the Xerces Society's pesticide program.



Aimée Code joined the Xerces Society in 2013 to direct its new pesticide program. In that role, she has built a program focused on securing practices and policies that promote ecologically sound pest management. She and her staff evaluate the risks of pesticides, develop technical guidance, and advocate for actions that reduce reliance on and risks of pesticide use in both urban and agricultural settings. Aimée received her master's of science in environmental health with a minor in toxicology from Oregon State University.

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