一心老大,你不会一直是直接喝渥太华的市政自来水吧?你够胆儿肥的啊!!
渥太华的市政自来水处理系统比较落后和陈旧,自来水质量不好。渥太华水厂把渥太华河的污染水只经过下面几个程序处理:(见
http://documents.ottawa.ca/sites/documents.ottawa.ca/files/documents/2013MOE_Britannia_en.pdf )
• coagulation (alum and sulphuric acid)
• flocculation (activated silica as a coagulant aid)
• sedimentation
• filtration (sand/anthracite)
• primary disinfection (sodium hypochlorite)
• pH correction (sodium hydroxide)
最后,水厂还在自来水中加注氯和氟化物送到你家。(氟化物会损害儿童智力,还可能引发骨癌;关于自来水中的氯气/氯化物,
Stackelberg also raised an X-factor: Rather than obliterating some pharmaceuticals, chlorination could chemically transform them into compounds that are even more toxic.
In one lab study, scientists found that acetaminophen, after undergoing chlorination, reacted to form tiny amounts of two known toxic compounds — 1,4-benzoquinone and N-acetyl-p-benzoquinone imine, the latter being associated with acetaminophen overdoses.)
然而,先进城市的市政自来水,都ban了加氟化物(比如欧洲和美国加拿大其它一些城市),消毒灭菌也不再用加氯气的方法,而是采用臭氧离子或紫外光。同时采用活性炭,逆渗透等方法减少和去除药物污染。比如美国加洲的 Orange County就用了RO技术;Greater Cincinnati水厂用了活性炭过滤;赌城Las Vegas花大钱用了现代先进技术处理自来水。
渥太华水厂的好处是省钱。