Cytotoxic and genotoxic assessment of agricultural soils from an industrial region.

Industrial effluents contain hazardous substances that can be a serious threat to the agriculture and human health. In the present study, the cytotoxic and genotoxic impacts of agricultural soil from the industrial area of Dera Bassi (Punjab, India) have been evaluated. Assays such as defects in DNA repair in K-12 mutants of Escherichia coli and chromosomal aberrations in Allium cepa were used to estimate the acute toxicity and chromosomal mutagenesis, respectively. Atomic absorption spectrometry and GC-MS analysis revealed contamination of the soil with high concentrations of heavy metals and organic compounds, respectively. Dichloromethane extract of site I soil sample caused maximum damage to 40 μL mL-1 DNA repair defective mutants and showed 38 and 49% survival in lexA and recA mutants, respectively, which was least among all the sites. In A. cepa test, an inverse relationship between soil extract concentration and the mitotic index was observed. Exposure of growing roots of A. cepa to soil extracts induced chromosomal abnormalities and alterations in mitotic phases in root tip cells. The study concludes that agricultural sites near the industrial area were contaminated with genotoxic and mutagenic compounds. Hence, adequate measures should be taken to reduce the toxicity of industrial effluents discharged onto the agricultural fields.