Registered as a U.S. pesticide in 2004. Reregistered in 2006. Currently under registration review.


Phorate is used in 21 states.

Map of where the organophosphate pesticide phorate is used in the 48 contiguous United States.

Phorate is used in Alabama, Arizona, California, Colorado, Florida, Georgia, Idaho, Illinois, Iowa, Kansas, Minnesota, Mississippi, Montana, Nebraska, North Carolina, North Dakota, South Carolina, Texas, Utah, Virginia, and Wisconsin.

Data is not available for Alaska, D.C., Hawaiʻi, and U.S. Territories. Data represents the most recent year available from USGS. Details.

See detailed maps of phorate usage by state and county.

Human Health Effects

Even at low levels of exposure, phorate can lead to serious negative health effects.

Neurodevelopmental Harm

High Risk Exposure Routes

Pesticide HandlersPeople involved in pesticide application process. Details.

High Residue Foods

Where residue levels of phorate exceeded allowable limits or were not legally allowed to have residues. Details.

[No high residue foods were specifically identified from the USDA’s PDP database.]

No detection does not necessarily mean there are no residues of concern. A relatively small sample of food products is tested and not all organophosphate pesticides are tested for.

Moreover, current U.S. pesticide tolerance levels are not protective against neurodevelopmental harm in children, so detections at or below tolerance levels do not indicate no harm.

Registered Uses

Where EPA allows phorate to be used.

Agricultural Crops: corn, cotton, other crops

Greenhouses and Nurseries

Additional Information

Estimated Use of Phorate on Crops

Most recent agricultural crop usage data as provided by the U.S. Geographical Survey’s Pesticide National Synthesis Project. Does not reflect universal usage of phorate. (How do EPest-low and EPest-high differ?)


EPest-low: Estimated use in millions of pounds of phorate by year and crop.


EPest-high: Estimated use in millions of pounds of phorate by year and crop.

U.S. Tolerances Categories & Commodities for Phorate

The U.S. EPA sets maximum residue limits — known as “tolerances” — on the amount of phorate that may remain in and on foods. The tolerance is the residue level that triggers enforcement actions.

Tolerances have been set for phorate for: Agricultural Commodities. Maximum residue limits have been set for phorate by the U.S. EPA for the following commodities:


U.S. EPA Human Health Risk Assessments for Phorate

Human Health Risk Assessments are conducted by the U.S. EPA to estimate the nature and probability of harmful health effects in people who may be exposed to pesticide. They are used to make informed decisions about approving new pesticides and new uses of registered pesticides, and during our regular review of existing pesticides. Read the assessment for phorate.