Organic arsenic is 500 times less harmful than inorganic arsenic. Persistent ingestion of Inorganic arsenic is linked with a broad variety of neurologic, cardiovascular, dermatologic and carcinogenic effects; including peripheral neuropathy, diabetes, ischemic heart disease, melanosis, keratosis and impairment of liver function.
Mercury is readily absorbed via respiratory tract. Inflammation of mouth and gums, swelling of salivary glands, excessive flow of saliva, loosening of teeth; kidney damage; muscle tremors, jerky gait, spasms of extremities; personality changes, discouragement, depression, irritability, nervousness, dementia, loss of motor coordination.
Lead can accumulate in organs such as the brain, bones, blood, kidneys and thyroid gland. This substance accounts for most of the cases of paediatrics heavy metal poisoning.