Cytotoxicity and Genotoxicity Evaluation of Some Stored Grain Insects and Their Infested Flour Using the BHK-21 Cell Line in an In Vitro Experimental Model

Globally, stored grain is vulnerable to pest infestation, resulting in significant economic losses for some crops. Wheat is one of the most important crops in the world. Many sucking, piercing insects infect wheat in the form of grains or flour and may produce toxic residues that are harmful to human health. The current study aimed to estimate the safe use of four stored grain insects by evaluating the potential genotoxic effects and cytotoxicity of crushed insects (T. granarium, S. oryzae, R. dominica, and T. castaneum) and their flour residues. MTT and comet assays were conducted to assess the effects of six concentrations of insect flour residues (0, 6.5, 12.5, 25, 50, and 100%) on the baby hamster kidney cell line (BHK-21). The lowest BHK-21 cell viability was noted against T. granarium (LC50% 36.42 μg/ml) followed by T. castaneum flour (LC50% 46.73 μg/ml) compared to the control (LC50% 808.2 μg/ml). Significantly high DNA comet (%) was observed in the treatments of T. castaneum flour (18.8%), S. oryzae wheat (15.6%), T. granarium (15.4%), T. castaneum (13.6%), and T. granarium wheat (13.1%). FTIR spectra of stored grain insects and their flour residues identified various functional metabolite groups, including alkynes and phenols, which could enhance cell apoptosis and genotoxicity. T. granarium, T. castaneum, and their flour residues had the highest cytotoxic and genotoxic effects on the BHK-21 cell line. The current study concludes that insect residues in flour may have cytotoxic and genotoxic effects on living cells, potentially affecting public health, particularly after consuming T. granarium and T. castaneum-infested flour. Therefore, good storage of stored grains and their products is recommended.