Where It Comes From
Public health mosquito-control programs applying larvicide to ponds, marshes, and sometimes household water storage containers; it is not typically used in homes [1][2].
How You Are Exposed
Drinking or skin contact with recently treated water; breathing spray mist near applications; occupational exposure when mixing or applying it [1][2].
Why It Matters
Temephos can inhibit cholinesterase, causing symptoms like headache, nausea, sweating, and muscle twitching at higher doses; severe poisoning can impair breathing [1][3]. When used as directed, expected levels in drinking water are low and not a health concern for the general public [1].
Who Is at Risk
Pesticide applicators; infants and children; people with certain enzyme deficiencies or on cholinesterase-inhibiting medicines; communities that rely on treated water storage [1][3].
How to Lower Your Exposure
Follow local mosquito-control notices; avoid contact with water during and right after treatment; wait or use alternative water if containers were just treated, per local guidance; workers should use PPE and cholinesterase monitoring [1][2][3].
References
- [1]WHO. Temephos in Drinking-water: Background document for development of WHO Guidelines for Drinking-water Quality. 2009.
- [2]U.S. EPA. Temephos: Reregistration Eligibility Decision (RED) and Fact Sheet. Office of Pesticide Programs.
- [3]ATSDR. Organophosphate Insecticides — ToxFAQs/Medical Management Guidelines. Agency for Toxic Substances and Disease Registry.