There are trace amounts of heavy metals such as arsenic and lead in food grade SHMP. Arsenic can cause systemic chronic poisoning mainly due to skin depigmentation, coloration, keratinization and cancer. Food grade sodium hexametaphosphate also has a certain content of fluoride. Low concentrations of fluoride can cause chronic poisoning and skeletal fluorosis, reduce calcium in the bones, and lead to osteosclerosis and osteoporosis.
However, these hazards are only possible in the case of long-term exposure. Food safety administration has set the minimum standards for these harmful substances in food grade SHMP after a large number of animal experiments and actual conditions. Generally, it is below the minimum content, so the the above-mentioned toxic and side effects won’t occur.