Australian Drinking Water Guidelines has approved over 30 toxic chemicals to ‘purify’ our water.
Here are the reasons given for using chemicals:
In the production of drinking water, a number of different chemicals may be added to the water. The types and quantities of chemicals can vary widely and will depend on a range of factors including raw water quality, treatment processes employed and treated water quality objectives. Chemical treatment processes are used to:
• control algae;
• remove turbidity and colour;
• remove microorganisms;
• remove algal metabolites and synthetic pollutants;
• reduce organic matter;
• reduce the concentration of iron, manganese and other elements;
• reduce pesticides and herbicides;
• control taste and odour;
• soften;
• buffer or modify the pH;
• disinfect;
• control corrosion in distribution systems.
Chemical treatments may also be used for other public health measures, including fluoridation
(to prevent dental caries).
Chemicals recommended for use in the treatment of drinking water and their uses
- Aluminium chlorohydrates AlCl(OH)5 2005 Coagulation
- Aluminium sulfate (alum) Al2(SO4)3 1983 Coagulation
- Ammonia NH3 aq 1983 Generation of chloramines for disinfection
- Ammonium sulfate (NH4)2SO4 1983 Generation of chloramines for disinfection
- Calcium hydroxide (hydrated lime) Ca(OH)2 1983 pH correction, Softening,Corrosion control
- Calcium hypochlorite Ca(OCl)2 1983 Disinfection/oxidation
- Calcium oxide (quick lime) CaO 1983 Coagulation aidpH correction,Softening,Corrosion control,
- Carbon, powdered activated/granulated activated (PAC/GAC)C 1983 Adsorption
- Chlorine Cl2 1983 Disinfection/oxidation
- Chlorine dioxide ClO2 2005 Disinfection/oxidation
- Copper sulfate CuSO4 1983 Algicide
- Ferric chloride FeCl3 1983 Coagulation
- Ferric sulfates Fe2(SO4)3 1983 Coagulation
- Hydrochloric acid HCl 2005 pH correction
- Hydrofluorosilicic acid(fluorosilicic acid) H2SiF6 1983 Fluoridation
- Hydrogen peroxide H2O2 1983 Disinfection,Oxidation
- Hydroxylated ferric sulfate 2005 Coagulation
- Ozone O3 2005 Disinfection/oxidation
- Polyacrylamides (C3H5NO)n 1977 Coagulation aid,Flocculation aid,Filter aid
- Polyaluminium chlorides Aln(OH)mCL(3n-m) 1979 Coagulation
- Poly aluminium silica sulfates Na12(AlO2),(SiO2)12.xH2O,2005 Coagulation
- Polydiallyldimethylammonium,chlorides (polyDADMACs) 1982 Coagulation and coagulation aid
- Potassium permanganate KMnO4 1983 Disinfection/oxidation
- Sodium aluminates NaAlO2 1983 Coagulation
- Sodium bicarbonate NaHCO3 1938 pH correction,Softening,Corrosion control
- Sodium carbonate (soda ash) Na2CO3 1983 pH correction,Softening,Corrosion control
- Sodium fluoride NaF 1983 Fluoridation
- Sodium fluorosilicate Na2SiF6 1983 Fluoridation
- Sodium hexametaphosphate (NaPO3)x 1983 Corrosion control
- Sodium hydroxide (caustic soda) NaOH 1983 pH correction,Softening,Corrosion control
- Sodium hypochlorite NaClO 1983 Disinfection/oxidation
- Sodium silicate Na2SiO3 1983 Coagulation aid,Flocculation aid,pH correction,Corrosion control
- Sodium tripolyphosphate Na5P3O10 2005 Corrosion control,Softening
- Sulfuric acid H2SO4 1983 pH correction
- Zinc orthophosphate Zn3(PO4)2 1987 Corrosion control
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