Exploring the Health Impact on Antimicrobial Contaminants in Leather Industries Effluent in Vellore, India: Distribution and Risk Analysis

This study investigates the presence and risks of common industrial antimicrobial agents used, in the vicinity of Vellore's leather industrial hub, Tamil Nadu, India. Water and sediment samples (n=25 each) were collected from two major tannery clusters, Ranipet and Ambur-Vaniyambadi. Using GC-MS and UPLC-DAD analyses, we attempted to detect six major antimicrobial classes such as chlorinated phenols, 2-(Thiocyanomethylthio) benzothiazole (TCMTB), ortho phenyl phenol (OPP), Para chloro m-cresol (PCMC), triclosan (TCS) and n-Octyl-isothiazolinone (n-OIT). Among them, only TCMTB, OPP, and PCMK were recorded in water samples, whereas in sediment samples none of the antimicrobials were found. Detection frequencies in water were 24%, with PCMC levels reaching up to 910 µg/L, TCMTB at 45.3 µg/L, and OPP at 821.3 µg/L. A comparative analysis with global studies showed that contaminant levels in this study are significantly higher than in other country reports. Human health risk assessment, based on USEPA methods, revealed a risk quotient (RQ) of 5.200 for PCMC, indicating a potential health risk, whereas TCMTB and OPP presented lower risks. Environmental risk assessment indicated hazard quotients (HQ) >1 for all detected antimicrobials, suggesting significant ecological risks. The study highlights the need for stringent regulations, improved industrial practices, and better wastewater treatment infrastructure. Continuous monitoring and more comprehensive studies with increased sampling are essential to develop strategies for reducing contaminants from leather industry runoff. These measures are crucial for protecting human health and aquatic ecosystems in the region.