principal pollutant meaning in English

主要污染物

First , it gives a brief introduction of how chinese current municipal water pollution is like and its features , noting what we are facing is a far cry from ever : daily sewage " s becoming the principal pollutant ; industrial sewage " s still strongly negative influence and various pollution sources etc . second , concerning the change of municipal water pollution from 1960s to 1990s , it indicates the process of the legislation
本章先简要介绍了我国目前城市水污染的状况及其特点，指出当前形势下城市水污染已不同于以往的污染状况，即生活污水已取代工业废水成为首要污染源，但工业污水的负面效应依旧强烈以及污染源的广泛性等等。