conductivity;
pH;
oxidizable substances [determined by the European Pharmacopoeia (EP) method or as redox potential determined by the United States Pharmacopoeia (USP) method];
total hardness (salts of Ca2+, Mg2+, Sr2+ expressed as mmol CaCO3);
total dissolved solids (TDS) determined as evaporative residue;
inorganic phosphate [Pi] and inorganic silicate [SiO2], determined as the molybdate reactive species;
chloride [Cl---].