We already calculate the acceptance limit for every equipment by using 4 method ( therapeutic daily dose, 10 ppm, LD50 and PDE) and we have Product A which is the minimum daily dose is 1mcg. So far Product A will be produced the lowest acceptance limit by using Therapeutic daily dose method calculation. But the limit too lowest and not possible for our analytical instrument (UPLC,UV,TOC and conductivity) to achieve the limit. The limit is 0.004um is too lowest. And not possible for us provide the dedicated equipment for produce this product. Do you have any option to solve this problem.