最近,加拿大联邦政府下令,全面检测全国自来水,以了解其中是否含有致癌物。加拿大卫生署正在挑选此项工程承包商,希望能查出所谓的消毒副产品是否流进自来水管中。长期以来,加拿大自来水处理厂一直使用氯及臭氧消除饮用水中的病菌。但20世纪70年代,科学家发现, Recently, the Canadian federal government ordered a comprehensive testing of tap water throughout the country to see if it contains carcinogens. The Canadian Department of Health is selecting the project contractor to find out if so-called disinfection by-products are flowing into tap water pipes. For a long time, Canadian water treatment plants have been using chlorine and ozone to eliminate bacteria in drinking water. However, in the 1970s, scientists found that,