Halogenated Compound

A halogenated compound is an organic molecule bearing one or more halogen atoms (fluorine, chlorine, bromine, iodine). The carbon-halogen bond resists degradation, so many are persistent, bioaccumulative, and toxic. Marine-relevant classes include PCBs, DDT, dioxins, brominated flame retardants such as PBDEs, and per- and polyfluoroalkyl substances. Several are listed under the Stockholm Convention as persistent organic pollutants. In anoxic sediment, microbial reductive dehalogenation can strip halogens and lower toxicity, but the parent compounds biomagnify through marine food webs to top predators.