Electrochemical simulation of triclosan metabolism and toxicological evaluation

Triclosan is a broad spectrum antibacterial or antifungal agent found in some consumer products. Such as in antiseptic soaps, toothpaste, detergents, cosmetics, plastic kitchenware, carpets, socks and toys. Pharmaceuticals and personal care products raise concerns in recent years about triclosan potential threats to human health and ecosystem. The demand of triclosan globally continues to increase and its production exceeded to 1500 tons per year worldwide. Given its widespread application it has been detected in wastewater, soil, sediment and surface water. Hence, the purpose of this research study is to investigate phase I metabolism of triclosan using electrochemical simulation. Also it tends to examine toxicological effects and its metabolites.


Toxicological evaluation of Triclosan

Using the QSAR modeling tool was performed to evaluate the toxic potential values  on the tested compound. In which the specific adverse effects were predicted by analyzing binding affinity towards each protein. Toxicological effects of triclosan on zebrafish embryos include delay of otolith formation, spine malformation, pericardial edema and late eyes formation. Some other notable changes are retardation of eye, hemorrhage, yolk-sac shrinkage and low heartbeat rate. Clearly, toxicological effects of triclosan on zebrafish are consistent to other research studies in literature. Moreover, it also shows that metabolites may induce similar adverse effects particularly the cardiovascular disorder.


Indeed, the research study was successfully simulated triclosan metabolism using electrochemical evaluation and its metabolites using modeling tools and bioassays. There were eight potential metabolites  were form via hydroxylation, ether cleavage and cyclization. Two dioxin derivatives were discovered for the first time and acts as potential metabolites. However, after the electrochemical reaction leads to induced high toxicity on zebrafish embryos. Therefore, the changes of acute toxicity through three transformation pathways indicate that only ether-bond can detoxify triclosan. While other transformation products formed highly toxic.


Hence, the study highlights that triclosan and its metabolites can cause serious effects in aquatic ecosystem if it is used continuously. It should be regulated in products utilization and considered as the major contaminants in the environment. To avoid further damaged and disruption especially to aquatic organisms and even to humans. Since most of the products containing triclosan are rinsed down and enter into sewerage and waste effluent.


Source: Prepared by Joan Tura from Science of the Total Environment

Volumes 622–623, 1 May 2018, Pages 1193-1201