The most important test is peroxides level which is NMT 400 ppm. The peroxides level comes from related impurities produced during its synthesis. The peroxides are known as potent oxidizer agents for drugs liable for oxidation.

An accident reported by FDA for crospovidone batch produced by Chinese Pharmaceutical Company where the peroxides level are more than 400 ppm. FDA reported that any pharmaceutical manufacturers of any products contain this crospovidone batch should be rejected. Also, FDA reported that the limit of peroxides in PVP or crospovidone should not be more than 400 ppm.