However, Gaston Wu points out that in recent years Europeans have been looking at the "life cycle assessment" of products, demanding not only that the product itself is non-toxic but also the processes used to create it.
然而，台師大教授吳家誠指出，物理性的去污方式有其侷限，且是否合乎環保標準也仍待檢驗。近年歐洲講求產品「生命週期的分析」，不僅產品本身必須無害無毒，就連生產過程也都不能有問題。