1. A composition comprising: a hydroxymethyl-substituted phosphorus-containing compound selected from the group consisting of tetrakis (hydroxymethyl) phosphonium salt, C-Calkyl or C-Calkenyltris (hydroxymethyl) phosphonium salt and tris (hydroxymethyl) phosphine； and 2- (decylthio) ethanamine. 2. The composition of claim 1, wherein the weight ratio of the hydroxymethyl-substituted phosphorus-containing compound to 2- (decylthio) ethanamine is from 8: 1 to 1: 4.3. The composition according to one of paragraphs. 1 and 2, in which the hydroxymethyl-substituted phosphorus-containing compound is tetrakis (hydroxymethyl) phosphonium sulfate. 4. The composition according to one of paragraphs. 1 and 2, in which 2- (decylthio) ethanamine is a hydrochloric acid salt. 5. A method for controlling microorganisms in an aqueous or water-containing system, which consists in treating the system with a composition according to one of claims 1-4.6. The method of claim 5, wherein the aqueous or water-containing system is a system that is used or which is present in the production of oil or gas. The method of claim 6, wherein the production of oil or gas includes the use of injected and produced water, water sources for flooding and hydraulic fracturing, pond water, water in prefabricated tanks, functional fluids, drilling fluids, formation fluids or fluids used for overhaul of wells, fluids for hydrotests, fluids for stimulation, packer fluids and fluids for hydraulic fracturing, oil and gas wells, separation, storage and transportation systems and oil and gas pipelines, oil and gas reservoirs or topliva.8. The method of claim 5, wherein1. Композиция, содержащая: гидроксиметилзамещенное фосфорсодержащее соединение, выбранное из группы, включающей соль тетракис(гидроксиметил)фосфония, соль C-Cалкил- или C-Cалкенилтрис(гидроксиметил)фосфония и трис(гидроксиметил)фосфин； и 2-(децилтио)этанамин.2. Композиция по п. 1, в которой массовое соотношение гидроксиметилзамещенного фосфорсодержащег
