toxic and harmful substance meaning in Chinese

有毒有害物质
有害物质

Analysis and limitation requirement of toxic and harmful substances in paper product
纸制品中有毒有害物质分析及限量要求
Purifying water quality : the first will be through cell amine and ammonia nitrate into substance , then later nitrate into ammonia volatile substances , so as to achieve degradation of ammonia and some toxic and harmful substances , three - dimensional improvement of water quality , water color , improve transparency and efficiency of the effect of rapid detoxification , and the establishment of the ecological balance of water for aquaculture environment
净化水质：首先通过菌体的活动将胺及氨类物质转化成硝酸盐，尔后再将硝酸盐转化成挥发性物质氨，从而达到降解水中氨氮及一些有毒有害物质，立体改善水质、水色、提高透明度，并具有高效快速解毒的功效，建立养殖水环境的生态平衡。