Spectrochemical, biological, and toxicological studies of DDT, DDD, and DDE: An in-silico approach

Pesticides are used to control the various pests and disease carriers. Degradation and/or biotransformation alter their chemical and toxicological nature. An attempt has been taken to investigate the physicochemical, spectral, and toxicological nature of DDT [1, 1'-(2, 2, 2-trichloroethylidene) bis(4-chlorobenzene)] and its major derivatives. DDT is transformed into DDD [l, l-dichloro-2, 2-bis(p,p-chlorophenylethane)], and DDE [l, l-dichloro-2, 2-bis(p,p-chlorophenylethylene)] under reductive dechlorination conditions. They last longer in the fatty tissue due to fat-soluble features, and exhibit some harmful effects on the environment and biological systems. Herein, density functional theory along with the CAM-B3LYP/6-311g ++ (d, p) basis set has been employed to investigate their physicochemical, and spectral properties. In-silico methods were incorporated to evaluate their biological, and toxicological properties. Molecular docking and nonbonding interaction calculations were performed to investigate their binding properties and mode(s) of action against the human estrogen receptor (PDB ID: 6PYF), and serine/threonine-protein kinase PIM-2 (PDB ID: 2IWI). Further, molecular dynamics simulation was performed to check the deformability and interactions of protein and amino acid residues, respectively. ADMET (absorption, distribution, metabolism, excretion, and toxicity) and PASS (prediction of activity spectra for substances) predictions were performed to compare their biological and toxicological properties. DDT has the highest free energy, dipole moment, and chemical reactivity; meanwhile, DDE and DDD have the highest binding affinity against both proteins. All the compounds exhibit hepato-toxicological, neuro-toxicological, and carcinogenic properties which depict their toxicological level. Based on their studied parameters, this study can help to increase awareness and provide a deeper understanding of the biochemical, and toxicological impacts on the environment and biological system.