Chromosome damage in peripheral lymphocytes of sheep induced by chlorine in drinking water.

The potential of chromosomal damage associated with the effects of chlorine in drinking water was evaluated using chromosome aberrations and micronuclei as cytogenetic endpoints in the lymphocytes of peripheral blood of ewe lambs. The study assessed the in vivo effects of high chlorine doses (1.8 mg l(-1), based on Savo-Super disinfectant) in drinking water on the peripheral lymphocytes of sheep after 30 days. The frequency of aberrant cells (AB.C.) in the experimental and control groups was 31.80+/-13.68% AB.C. and 4.50+/-2.07% AB.C. respectively, and the increased AB.C. in the treated group was highly significant (P=/<0.001). In the experimental group chromatid breaks (26.20+/-10.47%) and gaps (24.20+/-13.94%) were the dominant types of aberrations, but statistically significant chromosome gaps and exchanges were also present. The frequency of micronuclei in peripheral lymphocytes of sheep in the control group was 21.17+/-4.36 per 1,000 binucleated cells and 64.20+/-22.51 per 1,000 binucleated cells in the experimental group. A significant increase in the frequency of micronuclei in peripheral lymphocytes of sheep was observed between the two groups (P=0.001).