Free Training for Healthcare Providers - OEHHA offers educational courses to health care providers on the recognition, treatment, and reporting of pesticide-related illness. Courses are available on-line or on-site. Each course is approximately one hour, and continuing medical education credits may be provided.

What are Pesticides?

Pesticides are used to control a variety of pests, such as weeds, insects, rodents, bacteria, mold, and more.  They are applied in agricultural fields, homes, , parks, golf courses, and buildings.  Some are also used on pets and people to protect them from insects (such as fleas and lice).    

the application of pesticides by hand truck and plane

In California, the use of pesticide is regulated by the Department of Pesticide Regulation.

There are many different types of pesticides such as insecticides, herbicides, rodenticides, and fungicides. Disinfectants, pheromone insect attractants, plant defoliants, plant growth regulators, and swimming pool sanitizers are also regulated as pesticides.  For a legal definition of pesticides, go to FIFRA.

Pesticide products contain both "active" and "inert" ingredients. Active ingredients are chemicals that act to control the pests. Inert ingredients are solvents, dispersants, and other substances that are added to pesticide formulations to improve their effectiveness and product performance. Both active and inert ingredients can be toxic and need approval to be included in the final product.

Improper use or handling of pesticides may lead to build up in the environment, translocation to non-target locales (housing near application sites, for example), pesticide poisoning, and other health problems, as well as harmful effects on non-target organisms such as honey bees.  Exposures to pesticides may cause a wide variety of short-term (acute) and long-term (chronic) health effects, depending upon the type of pesticide and the amount of exposure.  Therefore, exposure to pesticides should be avoided whenever possible. 

pesticide warning - keep off

OEHHA Pesticides Related Activities

OEHHA performs a variety of activities related to the protection of human health from toxic effects of pesticides:

  • Education and outreach to health care professionals, local health officers and the general public
  • Surveillance of pesticide illness and injury
  • Evaluation of pesticide toxicity data and human exposure
  • Development of regulations on agricultural worker health and safety

OEHHA and the California Department of Pesticide Regulation (DPR) have shared responsibility for many of these activities.

Questions about Pesticides? Contact the Pesticides office: (510) 622-3170 or email

Reports, Notices, Documents

Apr 17, 2018: List of Registered Medical Supervisors
A list of registered medical supervisors in the biomonitoring program who measure cholinesterase activity in blood samples collected from agricultural workers who regularly handle category I and II organophosphate and carbamate pesticides.
Mar 5, 2018: Free Training for Healthcare Providers
Courses are available on-line or on-site. Each course is approximately one hour, and continuing education credits may be provided.  Courses are available in English and Spanish.
Dec 19, 2017: Guidelines for Physicians-6th edition (December 2017)
OEHHA publishes the Guidelines for Physicians - a booklet that describes the state program of ChE monitoring for agricultural pesticide mixers/loaders/applicators who regularly handle toxicity Category I and II OP or CB pesticides.