The mainland will lower the threshold for convicting polluters and punish them more severely as part of efforts by the new leadership to address growing public anger over environmental degradation.
The move follows a judicial interpretation of environmental protection provisions in the Criminal Law announced yesterday.
The Supreme People's Court and Supreme People's Procuratorate jointly issued the document to clarify the criteria for convictions for environmental crimes, court spokesman Sun Jungong said. The tightened rules were expected to help environment officials obtain harsher penalties for offenders.
The interpretation, which comes into effect today, states that a person can be convicted if he or she causes pollution that seriously injures a person. Previously, an incident would have had to result in a death before a person was convicted.
And only one death arising from an incident will be enough to see a sentence increased, rather than three deaths.
Sun said the lowering of the threshold for convicting polluters demonstrated authorities' determination to "fight and deter environmental crimes".
Compared with the articles on pollution offences in the Criminal Law, which only give broad instructions, the interpretation details 14 activities that will be considered "crimes of impairing the protection of the environment and resources".
Dumping radioactive substances into sources of drinking water and nature reserves, and incidents that poison more than 30 people or force more than 5,000 people to be evacuated, will be considered environmental pollution crimes for the first time.
The top prison sentence for environmental crimes is 10 years.
Wang Jin, a professor of environmental law at Peking University, said the legal interpretation was significant because law enforcement officials now had concrete instructions on how deal with polluters.
"Pollution has been terrible in recent years. The legal interpretation, with all its details, gives officials what they need to crack down on polluters," he said.
Air pollution in Beijing and other major cities reached levels deemed hazardous to health earlier this year.
Public anger boiled over last month when more than a thousand people took to the streets of Kunming, Yunnan, to protest against the local government's plan to build a petrochemical refinery and a related paraxylene plant near the city.
Chen Jiping, deputy director of the China Law Society and a former top law and order official, said at the annual meeting of the National People's Congress in March that pollution had replaced land disputes as the main source of social unrest in the past few years.