**16. Comet assay**

DNA damage of insects living in contaminated environment has been evaluated by the comet assay [69]. Using the comet assay, earlier investigation regarding DNA damage due to environmental contaminant can be established as DNA damage shows the molecular abnormalities that can cause pathogenic adversity. The environmental potential for genotoxicity in terrestrial insects can be measured by the comet assay, therefore, it aids in providing the early management of xenobiotic hazards which is evaluated by this assay [70, 71]. Kheirallah *et al.* [72] had reported the beetles as biomonitoring model to evaluate the DNA damage in a contaminated terrestrial environment [72]. Over recent years, chromosomal research had been of great importance due to increased demand to assess the genotoxicity of aquatic of environmental toxicity [73]. Various organisms at the end of trophic level of food chain are at severe risk of toxicology because of genotoxin presence in aquatic environment [74] as exposure causes DNA damage.
