1,2,4-Trichlorobenzene

1,2,4-Trichlorobenzene is an organochlorine compound, one of three isomers of trichlorobenzene. It is a derivative of benzene with three chloride substituents. It is a colorless liquid used as a solvent for a variety of compounds and materials. == Production and uses == Depending on the conditions and additives (e.g., sulfur), it can be the main product from the chlorination of benzene. It is virtually the exclusive product from the chlorination of 1,4-dichlorobenzene. It is also the main product from the dehydrochlorination of hexachlorocyclohexane. It is useful as a high-temperature solvent, e.g. for gel permeation chromatography of polyolefins such as polyethylene or polypropylene. Aside from its use as a solvent, this compound is a useful precursor to dye and pesticides. == Safety == The LD50 (oral, rats) is 756 mg/kg. Animal studies have shown that 1,2,4-trichlorobenzene affects the liver and kidney, and is possibly a teratogen. There is no regulated occupational exposure limit for chemical exposure, but the National Institute for Occupational Safety and Health recommends no greater exposure than 5 ppm, over an 8-hour workday. == See also == Chlorobenzenes—different numbers of chlorine substituents and isomeric forms == References ==