(2) The pollution of industrial wastewater and waste residue containing chemical poisons in drinking water will cause methyl mercury poisoning, arsenic poisoning, cadmium poisoning and other public hazards.
(3) Lack of iodine and high fluoride in drinking water will make people suffer from endemic diseases such as goiter, cretinism, dental fluorosis, skeletal fluorosis and Kaschin-Beck disease.
(4) If there is no or little fluoride in the drinking water, osteoporosis and dental caries in children will occur, which will affect the physical development.
(5) Drinking water without calcium, magnesium and other minerals will obviously increase the incidence of coronary heart disease and other diseases.