Contribution of chlorination to the mutagenicity, genotoxicity and presence of mutagens in potable water

Abstract

This study evaluated the mutagenic and genotoxic activities produced by three types of water: 1) raw polluted water which supply a treatment plant, 2) water after it has been treated including chlorination, and 3) the domiciliary potable water. The Ames test found that raw water at pH 7 in the plant exhibited high indirect mutagenic effect, over seven times the control, but after this water was treated and chlorinated in the plant produced low indirect mutagenicity, only two and half times the control. This result may indicate that the 65% of the polluted mutagenic materials were removed by the treatment in the plant, but, the chlorinated water at pH 2 increased ostensibly the direct mutagenicity, which was eight times over the mutagenicity from the control in the strain TA100. The same mutagenic pattern was observed but in lower amounts in the domiciliary drinking water. All three types of water samples also, exhibited high genotoxicity in human lymphocytes. This may indicate that mutagens present in this drinking water can damage human DNA in these cells, therefore may implicate a risk for human health. After analyzing neutral extracts from domiciliary drinking water, using GC/MS, five polycyclic aromatic hydrocarbons (PAHs) were detected: Naphthalene 1,1’ (1,10 decanedyl) bis, phenanthrene 9 dodecyltetradecahydro, dibenz(a,h)anthracene 1,2,3,4 tetrahydro, 9,9’ biphenantrene octacosahydro, and benz(a)anthracene 7,12 dimethyl. The four first of them PAH have been recognized as mutacarcinogens. In this water, it was identified the hormone Androstane 5 alpha.