A halogenated ethylene compound of the formula: where R.sub.1 and R.sub.2 are hydrogen, optionally substituted alkyl or together form a cyclohexyl group; X is bromine, chlorine or iodine and Y.sub.1 and Y.sub.2 are chlorine, bromine or iodine. A compound of this type is 2,3-dibromo-1-chloro-4-thiocyanato-2-butene. The compound has good anti-fungal and anti-bacterial properties. The compound can be used as an industrial biocide.