Investigation of combined genotoxic effect of pesticides on cancer cell lines

Abstract

The use of pesticides in agriculture sector is increasing widely to alleviate crop loss due to pests. To combat problem of pest, various types of pesticides are widely used, out of which insecticide are majorly used. In Malwa region of Punjab lots of insecticides are used. These pesticides when present together they may result in combined response. This combined response can be of three types such as independent, dose addition and interaction (synergism or antagonism). This combined response is very big trouble, such as sometimes even low dose of pesticide which is not toxic individually can result in toxic response in the presence of another pesticide. In the present study, Malathion and Monocrotophos (widely used organophosphorous insecticides) selected for investigation of combined effect. Out of selected pesticide Malathion also detected in water, in present study. Various parameters for genotoxicity evaluation was carried out with exposure of pesticides on HCT-116 WT/ p53 mutant (colon cancer) cell lines. Results of present study suggested that combination of pesticides resulted in more cell death, oxidative stress, membrane instability and imbalanced antioxidative system. It is also evaluated that low dose exposure of pesticides individually and in combination resulted in increased cell survival, may be due to activation of defense mechanism with prior treatment. All parameters evaluated was with short term exposure of 1-2 days, so evaluated long term exposure of ten days and found that this resulted in very less cell number and changed cell morphology. It is observed that both pesticides showed genotoxicity individually as well as in combination. The combined exposure of both pesticides deviate from there expected effect for dose addition towards more toxicity. So it is concluded that there may be some interaction between these pesticides, which may be synergistic in nature, because observed more toxicity.