What Is Malathion?
The National Pesticide Information Center describes malathion as an organophosphate insecticide used outdoors to control a wide variety of insects on farms and around homes, and says it has also been used in public health mosquito control and fruit fly eradication programs. The EPA says malathion is used to kill adult mosquitoes, with about 90 percent of those applications made by truck-mounted fogging equipment.
NPIC says malathion binds to the enzyme that stops a nerve signal, so the nerves keep signaling each other without stopping, and the EPA's 2024 draft risk assessment says malaoxon, the active form of malathion, is responsible for interacting with the nervous system by inhibiting the acetylcholinesterase enzyme. NPIC says people exposed to enough malathion to become sick had nausea or vomiting, muscle tremors, cramps, weakness, shortness of breath, a slowed heart rate, headache, abdominal pain and diarrhea.
On July 17, 2024, the EPA released its proposed interim registration review decision for malathion, which proposes mitigation measures to reduce potential ecological risks.
Sources checked September 15, 2026. Every point below links the page it came from.
The sources behind this answer
- Government sourceNPIC describes malathion as an organophosphate insecticide used outdoors on farms and around homes, which has also been used in public health mosquito control and fruit fly eradication. National Pesticide Information Center, Oregon State University ↗
- Government sourceNPIC says malathion binds to the enzyme that stops a nerve signal, so the nerves keep signaling each other without stopping. National Pesticide Information Center, Oregon State University ↗
- Government sourceNPIC says people exposed to enough malathion to become sick had nausea or vomiting, muscle tremors, cramps, weakness, shortness of breath, a slowed heart rate, headache, abdominal pain and diarrhea. National Pesticide Information Center, Oregon State University ↗
- Government sourceThe EPA says malathion is used to kill adult mosquitoes, and about 90 percent of those applications are made with truck-mounted fogging equipment. US EPA ↗
- StudyThe EPA's 2024 draft risk assessment says malaoxon, the active form of malathion, interacts with the nervous system by inhibiting the acetylcholinesterase enzyme. US EPA ↗
- Regulatory filingOn July 17, 2024 the EPA released its proposed interim registration review decision for malathion, proposing mitigation measures to reduce potential ecological risks. US EPA ↗
Sources checked September 15, 2026. A brand statement is the company’s own claim, which we report but have not verified. Our grades are model-based estimates, not lab tests.