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Related to trihalomethane: chloroform
Any of several chemical compounds in which halogen atoms replace three of the hydrogen atoms normally present in a methane molecule. These toxic compounds can occur in chlorinated water as a result of reaction between organic materials in the water and chlorine added as a disinfectant.
(Chemistry) a type of chemical compound in which three of the hydrogen atoms in a methane molecule have been replaced by halogen atoms, esp by chlorine in drinking water. Trihalomethanes are thought to be carcinogenic