CHLORINE: AN UNNECESSARY EVIL?

Chlorination in drinking water over the past 20 years has led to the discovery of 600 toxic disinfectant by-products. The main ones: chloramines and trihalomethanes are now regulated in most countries and recognised as toxic, and, in the case of trihalomethanes, carcinogenic. But this still only accounts for 25% of other disinfectant by-products such as halonitromethanes (HNMs), haloamides, and iodo-DBPs are proving to be far more cyto and geno toxic (i.e. they attack cells and cell DNA). So, whilst the swimming pool industry perpetuates its health and wellness tag, there is a ‘wellness paradox’ where swimmers are exposed to unregulated toxic chemicals which have health implications for all. The environmental implications are also significant, with the embodied energy in chlorine production similar to that of steel. So do the positives of chlorine outweigh these significant negatives? With advancing chlorine-free technologies becoming established, and available for private pools, is chlorine an unnecessary evil?