Organochlorine Contaminant, Triclosan Leads to Increased Levels of Trihalomethanes in Drinking Water Sources across the United States

Abstract

Organochlorine contaminants, such as Triclosan (TCS), are present in drinking water sources across the United States. Since TCS was developed in the late 1960s, antimicrobial compounds have been widely used as multipurpose ingredients in everyday consumer products, can be ingested or absorbed through the skin, and are found in human plasma, breast milk, and urine samples. Monitored by the United States Toxic Substances Control Act, TCS production was limited to 1 million pounds per year, yet by 1998 production of TCS steadily increased from 1 million pounds to 10 million, with an estimated production of approximately 14 million globally by 2011. Studies have shown that the expanded use of antimicrobial agents causes them to be found and remain suspended in the ecosystem, most notably the soil and watersheds. Research has shown emerging concerns related to the overuse of TCS, such as dermal irritations, higher incidence of antibacterial-related allergies, microbial resistance, endocrine system disruptions, altered thyroid hormone activity, metabolism, and tumor metastasis and growth, with overexposure playing a role in inflammatory responsiveness, which could cause adverse outcomes and is associated with numerous pathologies, including cardiovascular disease and several types of cancers. To understand the impact of the overuse of TCS-containing products on water quality before the Food and Drug Administration (FDA) began to require pre-market approval, we have analyzed the data reported between March 2005 and 2015 by Consumer Confidence Report (CCR) on the levels of total trihalomethanes (TTHM), such as chloroform, a product of free chlorine added to TCS in the metropolitan areas primary water sources across the United States, as they correlated to increased production of antibacterial agent, TCS. Our study concluded that increased use of products containing the antimicrobial agent TCS contributes to higher levels of total organochlorine contaminant, trichloromethane, leading to an increase in TTHM levels recorded annually on water quality reports.