Public Health Statement for Malathion
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Public Health Statement for Malathion
This Public Health Statement is the summary chapter from the Toxicological Profile for Malathion. It is one in a series of Public Health Statements about hazardous substances and their health effects. A shorter version, the ToxFAQs™, is also available. This information is important because this substance may harm you. The effects of exposure to any hazardous substance depend on the dose, the duration, how you are exposed, personal traits and habits, and whether other chemicals are present. For more information, call the ATSDR Information Center at 1-888-422-8737.
This public health statement tells you about malathion and the effects of exposure.
The Environmental Protection Agency (EPA) identifies the most serious hazardous waste sites in the nation. These sites make up the National Priorities List (NPL) and are the sites targeted for long-term federal cleanup activities. Malathion has been found in at least 21 of the 1,623 current or former NPL sites. However, the total number of NPL sites evaluated for this substance is not known. As more sites are evaluated, the sites at which malathion is found may increase. This information is important because exposure to this substance may harm you and because these sites may be sources of exposure.
When a substance is released from a large area, such as an industrial plant, or from a container, such as a drum or bottle, it enters the environment. This release does not always lead to exposure. You are exposed to a substance only when you come in contact with it. You may be exposed by breathing, eating, or drinking the substance, or by skin contact.
If you are exposed to malathion, many factors determine whether you'll be harmed. These factors include the dose (how much), the duration (how long), and how you come in contact with it/them. You must also consider the other chemicals you're exposed to and your age, sex, diet, family traits, lifestyle, and state of health.
What is malathion?
Malathion is a pesticide that is used to kill insects on agricultural crops, on stored products, on golf courses, in home gardens, and in outdoor sites where trees and shrubs are grown at home; it is also used to kill mosquitoes and Mediterranean fruit flies (medflies) in large outdoor areas. Additionally, malathion is used to kill fleas on pets and to treat head lice on humans. It is usually sprayed on crops or sprayed from an airplane over wide land areas, especially in the states of California and Florida. Malathion comes in two forms: a pure form of a colorless liquid and a technical-grade solution (brownish-yellow liquid), which contains malathion (greater than 90%) and impurities in a solvent. The technical-grade malathion smells like garlic. Malathion is a manufactured chemical, so it is only found in the environment as a result of its manufacture or use. Malathion has been manufactured in the United States since 1950 and has been used to kill insects on many types of crops since this time. The Food and Drug Administration (FDA) and the EPA allow a maximum amount of 8 parts per million (ppm) of malathion to be present as a residue on specific crops used as foods. Because malathion can be dangerous to humans, the EPA requires that a certain amount of time must pass between the time of application of the insecticide and entry by a worker into a field where the chemical has been applied. Usually, at least 12 hours must pass between application and entry, but in some cases, such as when workers are entering a field to hand harvest or hand prune the crops, time periods as long as 6 days must pass between application and entry into the field. In this way, exposure to malathion can be controlled and accidental exposures can be prevented.
What happens to malathion when it enters the environment?
Once malathion is introduced in