In late July, the California Department of Pesticide Regulation (DPR) announced new restrictions on structural pest control applications, which are applied around buildings to control ants, spiders, and other insects. The goal is to protect urban water quality by limiting pesticides applied on impervious surfaces and eliminating spraying during rainfall, on standing water, or over drainage areas.

The restrictions apply to pest control businesses and to 17 pyrethroid insecticides specifically. These particular insecticides were found in urban waterways and are toxic to sensitive aquatic organisms. DPR also has requested voluntary product labeling on pyrethroid products. According to the government-funded Urban Pesticides Pollution Prevention Project (UP3 Project), the restrictions and labeling program should reduce pyrethroid insecticides in urban stormwater runoff by 80% to 90%. Read more from the UP3 Project.