The maximum sentence for environmental pollution is seven years. 1. The crime of environmental pollution refers to an act that violates the laws and regulations on the prevention and control of environmental pollution, causes environmental pollution and causes serious consequences, and should be subject to criminal punishment according to law. 2. According to Article 338 of the Criminal Law of People's Republic of China (PRC), anyone who, in violation of state regulations, discharges, dumps or disposes of radioactive wastes, wastes containing infectious disease pathogens, toxic substances or other harmful substances, which seriously pollutes the environment, shall be sentenced to fixed-term imprisonment of not more than three years or criminal detention and shall also or only be fined; If the circumstances are serious, he shall be sentenced to fixed-term imprisonment of not less than three years but not more than seven years and shall also be fined; (1) Discharging, dumping or disposing of radioactive wastes, wastes containing infectious disease pathogens and toxic substances in key protected areas determined according to law, such as drinking water source protection areas and core protected areas of nature reserves, if the circumstances are particularly serious; (2) Discharging, dumping or disposing of radioactive wastes, wastes containing infectious disease pathogens and toxic substances to important rivers and lakes designated by the state, if the circumstances are particularly serious; (3) Causing a large number of basic functions of permanent basic farmland to be lost or permanently damaged; (4) Causing serious injuries or diseases to many people, or causing serious disability or death. Whoever commits the acts mentioned in the preceding paragraph and constitutes other crimes shall be convicted and punished in accordance with the provisions of heavier punishment.