Methoxychlor

Description

A white crystalline powder previously used as an insecticide. Methoxychlor was introduced as an insecticide in 1945. It is in the same chemical family as DDT but is more potent and is effective against most insects as well as their larvae. Methoxychlor has a long residual effect. It was banned in the U.S. in 2003 and in the E.U in 2002.

Synonyms and Related Terms

methoxy-DDT; dimethoxy-DDT (DMDT); 2,2-bis(p-methoxyphenol)-1,1,1-trichloroethane; Chemform; Marlate [DuPont]; Moxie; Metox; Methocide; Methoxo; Chemform

Applications

• Agriculture: sprayed extensively of fruits, vegetable and forage crops
• Applied to livestock, barns and storage bins
• Used in household bug sprays for cockroaches, fleas and mosquitos.
• Used in flea and tick drips for domestic pets

Personal Risks

• Overexposure causes convulsions and liver and kidney damage.
• Potential carcinogen.
• Decomposes when heated to produce toxic fumes of chlorides.
• Chemical Book: SDS

Environmental Risks

• Listed as a persistent, bio-accumulative and toxic chemical
• Because it is insoluble in water, it binds to soil and lake sediments
• Degradation half-life is about 120 days

Physical and Chemical Properties

• Soluble in ethanol. Insoluble in water.
• Composition = Cl3CCH(C6H4OCH3)2 (mol.wt. = 345.65 g/m)
• CAS = 72-43-5
• Melting Point = 78-78.2 C

Resources and Citations

• MuseumPests.net: Pesticide Database
• EPA: Archived Factsheet Methoxychlor
• Wikipedia: Methoxychlor Accessed Nov 2026