FDA Ban on Triclosan Leads to Major Changes in Levels of Trihalomethanes in Drinking Water Sources across the United States

Abstract

Since its development in the mid-1960s, antimicrobial Triclosan (TCS) has been added to many everyday household products. By 2010, TCS could be found in 93% of soaps and body washes sold nationwide due to its germ-killing capabilities. TCS overuse has led to public concern for the potential emerging health risks raised in the past decades. Although TCS has antibacterial properties that prevent or deter bacterial growth, in 2016, the US Food and Drug Administration (FDA) banned the sale of consumer antiseptic wash products containing TCS as the active ingredient. The ban stated that these TCS-containing household products may not be environmentally safe and provide minimal benefits. TCS is considered an endocrine disruptor that causes immune dysfunction, microbial resistance, altered thyroid hormone activity and affects human reproductive outcomes. Previous studies have shown that TCS is toxic to aquatic organisms and invertebrates and has been linked to the etiology of breast cancer and tumor metastasis. Research shows positive associations between the occurrence of antivirals and the detection of antibiotic-resistance genes with a higher incidence of antibacterial-related allergies. Our previous research examined the overuse of TCS-containing products, increasing total trihalomethane (TTHM) levels and affecting our water supply quality. To understand the impact of the FDA ban requiring pre-market approval, we analyzed data reported between 2016 and 2020 provided by the Consumer Confidence Report (CCR) on the TTHM levels, such as chloroform, a product of free chlorine added to TCS in primary water sources across the United States, as they correlated to decreased production of products containing TCS. Our study found that limiting the production of TCS had the desired effect by lowering levels of organochlorine contaminants, leading to a decrease in TTHMs recorded by metropolitan CCR data before the requirement rollback of the FDA in response to the COVID-19 pandemic in 2020.