Pyriproxyfen is an insecticide used to control a wide variety of insects including mosquitoes, roaches, houseflies and ants. It's used both residentially and in agriculture on fruits, vegetables and nuts. It works by inhibiting egg development and hormonal growth, preventing insects from maturing and reproducing.
Pyriproxyfen is generally not expected to be a water treatment concern.
Animal studies have shown pyriproxyfen to be mildly toxic with acute exposure, causing symptoms of eye irritation. Long term exposure primarily affected the liver and kidneys, though it is not believed to be carcinogenic.
The World Health Organization recommends granular activated carbon (GAC) for the treatment of pyriproxyfen.
Sources: WHO, EPA, Photo: WikiMedia, author: James Gathany, CDC
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