dibromochloromethane

Dibromochloromethane, with the chemical formula CHBr2Cl, is an organohalogen compound and a member of the trihalomethane family. It is a colorless, volatile liquid at room temperature and is generally sparingly soluble in water while dissolving more readily in organic solvents.

Formation and occurrence: Dibromochloromethane is primarily formed as a disinfection by‑product when chlorine- or chloramine-based disinfectants react with natural organic matter in water that contains bromide ions. In drinking water treatment, its formation tends to accompany other halogenated methanes, and its relative abundance increases with higher bromide levels in the source water.

Uses and occurrence in the environment: There are no large-scale commercial applications for dibromochloromethane itself. It is mainly encountered as a contaminant or by-product in treated water, and less commonly in certain chemical syntheses or laboratory contexts. Environmentally, it is expected to volatilize from water surfaces and may undergo degradation by natural processes, with distribution influenced by air-water partitioning.

Health and regulatory context: Dibromochloromethane is one of several disinfection by-products formed during chlorination of drinking water. Health agencies monitor total trihalomethanes due to potential health risks from chronic exposure, including cancer risk and reproductive effects, particularly through ingestion and inhalation exposure during showering or bathing. Regulations typically address the sum of THMs in drinking water rather than this compound alone, and water utilities manage treatment conditions to control overall THM formation.