Halogenated organic compounds are very toxic and anti-degradable due to the existent of halogenated basis.Their biological degradation is focus in a reducing reaction called dehalogenation.

• 卤代有机物由于有卤代基团的存在而具有很强的毒性和抗降解能力，其生物降解的关键步骤为脱卤反应，是还原反应。