Organic compounds in which a methyl group (CH3+) is attached to a CN- ion, where one or more of the hydrogen atoms are substituted by halogens (chlorine, bromine, fluorine and/or iodine). Examples of haloacetonitriles are bromochloroacetonitrile, chloroacetonitrile and dibromoacetonitrile. More: Although in the past, chloroacetonitrile and trichloroacetonitrile have had a limited use as pesticides, haloacetonitriles are not manufactured today. Haloacetonitriles do exist as a drinking water disinfectant byproducts when water is chlorinated as a consequence of the reaction of chlorine with natural organic matter and bromide ions in the raw water supply. For more information on the haloacetonitriles: WHO Â