Daily Echo - letters

This what the Chief Medical Officer says about the stuff they put in. The BFS call it a co-product but they would call it that rather than a waste product.

Water Industry Act, allows hexafluorosilicic acid (H2SiF6) and disodium hexafluorosilicate (Na2SiF6) to be used to increase the fluoride content of water. The published Code of Practice on Technical Aspects of Fluoridation of Water Supplies (Department of the Environment, 1987) gives specifications for these substances and states that 'the product. ..must not contain any mineral or organic substances capable of impairing the health of those drinking water correctly treated with the product'. For H2SiF6, limits are given for a number of possible impurities, including for iron, heavy metals, sulphate, phosphate, and chloride. The specification for Na2SiF6 powder requires a minimum of 98% m/m of the pure chemical, and gives maximum limits for impurities, including heavy metals (as lead) and iron. No other substances are allowed to be used in the fluoridation process, other than an anti-caking agent (the identity of which must be disclosed) in the case of Na2SiF6. Synthetic detergents are not permitted.

Thus there is no likelihood, in normal operation, for any fluoridation plants to introduce other compounds into the drinking water supply (other than approved anti-cakinq aqents and any impurities present in the fluoridation chemicals).