The effect of insecticides on Chinese hamster cell cultures

The effect of p,p'-isomers of DDT and its derivatives DDD, DDE and DDA on Chinese hamster cells in culture was studied. At different concentrations and various times of treatment the proliferation rate was inhibited most strongly by DDD and DDT, whereas DDE exhibited a markedly weaker influence. DDA was the least toxic compound of the four. The cytogenetic effects were also different. Again, DDA induced the least damage. Only enhanced gap rates but no chromosome breaks were observed. DDE was more active, and higher break rates occurred. DDD and DDT were by far the most damaging compounds, and they raised the gap and break rates markedly. However, no induction of configuration anomalies was found in any experiment. Chronic treatment of the cells for 3 months with DDT at 8 ppm did not alter the proliferation rate, the sensitivity to acute treatment with higher DDT concentrations or the chromosomal aberration rates. The results are discussed in relation to the relevance of differential pesticide effectivity in organs of higher animals and man.