Chemistry is a required course for middle-school students, but some experts are calling on the 258 middle schools in Harbin to be more careful about draining off chemical wastewater created in experiments, which they say is polluting the environment.

It is a new problem in environmental protection, said a chemical teacher for Harbin First Middle School whose surname is Xi when interviewed with Harbin Daily. Some materials used in senior middle-school students' organic experiments, such as phenol and bromobenzene, are poisonous. Benzene is a known carcinogenic. Some labs in middle schools have no means of direct disposal of experimental wastes, and disposal machines are expensive.

A chemical teacher in Harbin Sixth Middle School also thinks the school can do nothing in regard to laboratory pollution. He said if one class conducts chlorine experiments, the whole school fills with the smell of chlorine. And the smell of sulfur dioxide is more unpleasant. According to another teacher, although the school is a key school, its laboratories have no recycling equipment for wastewater that is poured into the sewer -- let alone what goes on in ordinary schools

Middle-school students need to conduct many experiments, according to teaching programs, and half of them involve acidic or alkaline reactions that are poisonous. With dense acids and alkali, teachers ordinarily pour them into specific containers for other experiments or to wash containers. They pour the liquid into sewers after it has become less poisonous. Some schools bury corrosive and dangerous wastes. As gases are not easy to reclaim, some teachers reduce their pollutions through acid-base neutralization. A few schools are equipped with ventilation machines to pump out poisonous gases, but this only transfers pollutants to other places.

Fan Qingxin, professor for the Environmental Engineering School of Harbin Institute of Technology and an expert in laboratory environment protection, said school laboratories are contributing much harm to the environment since many sewers link directly to rivers in Harbin. Even if the chemical wastewater soaks into the earth, the pollution to the environment is tremendous. Foreign schools all have special recycling programs, which need funds but are required. And delivering laboratory wastes to special places for treatment is a basic social responsibility.

Fan advised middle schools to do harmless experiments to protect environment. He added that schools should pay more attention to the construction of laboratories and the training of lab assistants. Environmental protection departments can also ask chemistry departments to collect experiment wastes. In a word, he said, creating pollution should not be a by-product of any study to further knowledge.

(Yue Tongming for 新华网 [Xinhua News Agency] January 21, 2002 translated by Feng Yikun for china.org.cn)