In silico toxicological analyzes of selected toxic compounds from dumpsite or contaminated soils on human health

Abstract

The soil is a key component of natural ecosystems because environmental sustainability depends largely on a sustainable soil ecosystem. The objective of this study was to predict the impact of selected toxic compounds from dumpsite or contaminated soils on human health at the molecular level of biological processes. The in silico methods that were used include toxicokinetics and target gene prediction, molecular docking, and gene expressing network analysis. The result showed bisphenol A (BPA), 2,20-bis(p-chlorophenyl)-1,1-dichloroethane (DDD), 2,20-bis(p-chlorophenyl)-1,1-trichloroethane (DDT), diethylhexyl phthalate (DEHP), nonylphenol (NP) and tetrachlorodibenzodioxin (TCDD) as the active toxic compounds that can modulate biological system and are considered as potential cause of several diseases including cancer. The principal target genes include substance-P receptor (also known as Neurokinin 1 receptor), 5-hydroxytryptamine receptor, human serotonin transporter; estrogen receptor alpha; and aryl hydrocarbon receptor. These genes implicated SUZ12, STAT3, and TRIM28 as the major transcription factors while mitogen-activated protein kinases and cyclin-dependent kinases were the major kinases from the protein-protein interaction. All the six toxicants investigated showed good free binding energies (ΔG) which were below - 5.0 kcal.mol⁻¹. These toxic compounds showed ligand efficiency greater than 0.25 kcal.mol⁻¹. HA and would possibly cause fatal damage on human health. The order of in silico predicted toxicity of these compounds were BPA > DDD = DDT > TCDD > NP > DEHP. Our results identified potential threats, which the selected toxicants can pose to public health. More importantly, it provides basis for investigation of super bugs (microorganisms) that can remediate these toxicants in our environment. Environmental monitoring and modern wastes management system should be implemented and enforced in the affected countries in order to safeguard the health of the citizenry.