我们可以少些谈观点,多谈事实,贴一个WHO水标白皮书里面关于重金属检测的位置:
"For verification of chemical safety, testing for chemicals of concern may be at the end of treatment, in distribution or at the point of consumption (depending on whether the concentrations are likely to change in distribution)."
whqlibdoc.who.int/publications/2011/9789241548151_eng.pdf?ua=1