On July 30, the California Department of Pesticide Regulation released its comprehensive risk assessment of chlorpyrifos. Per that document, a scientific panel has recommended chlorpyrifos be listed as a toxic air contaminant (TAC). Now, the state’s department has 10 working days to officially begin the process to list chlorpyrifos as a TAC.
As defined in California, a TAC is “an air pollutant which may cause or contribute to an increase in mortality or an increase in serious illness, or which may pose a present or potential hazard to human health.”
This final TAC evaluation focused on the developmental neurotoxicity effects that chlorpyrifos has as a potential risk. This was “the critical endpoint for the chlorpyrifos risk assessment.”
Specifically in California, chlorpyrifos first entered the comprehensive risk assessment process in 2011. The first draft of its risk assessment detailed the risk of human exposure to spray drift, which was published in December 2015. Following that, the chemical entered the state’s formal TAC evaluation process, and the first draft of its related evaluation was published in August 2017.
Nationally chlorpyrifos is found in products registered by about 20 different companies. It has been a much reported story as its EPA registration has been challenged. As reported by AgWeb, in 2007 Dow AgroSciences’ chlorpyrifos was forced into an early review when two activist groups filed a petition with EPA to revoke tolerances and cancel EPA registrations for the product based on food tolerances. And in late March, EPA ruled it will not ban the pesticide. That resulted in five states suing the EPA. That may have lead California to start restricting its permitted use in the state as early as the following August.
This is a trend as states have increasingly used their agencies and review processes to evaluate pesticide regulations. In June 2018, Hawaii became the first state to ban chlorpyrifos. At the time of that legislation being signed by the governor, state senator Mike Gabbard provided said, “other states will follow our example.”