Occurrence of triclosan, triclocarban, and its lesser chlorinated congeners in Minnesota freshwater sediments collected near wastewater treatment plants

Abstract

The antimicrobial agents triclosan (TCS), triclocarban (TCC) and their associated transformation products are of increasing concern as environmental pollutants due to their potential adverse effects on humans and wildlife, including bioaccumulation and endocrine-disrupting activity. Analysis by tandem mass spectrometry of 24 paired freshwater bed sediment samples (top 10 cm) collected by the U.S. Geological Survey near 12 wastewater treatment plants (WWTPs) in Minnesota revealed TCS and TCC concentrations of up to 85 and 822 ng/g dry weight (dw), respectively. Concentrations of TCS and TCC in bed sediments collected downstream of WWTPs were significantly greater than upstream concentrations in 58% and 42% of the sites, respectively. Dichloro- and non-chlorinated carbanilides (DCC and NCC) were detected in sediments collected at all sites at concentrations of up to 160 and 1.1 ng/g dw, respectively. Overall, antimicrobial concentrations were significantly higher in lakes than in rivers and creeks, with relative abundances decreasing from TCC > TCS > DCC > NCC. This is the first statewide report on the occurrence of TCS, TCC and TCC transformation products in freshwater sediments. Moreover, the results suggest biological or chemical TCC dechlorination products to be ubiquitous in freshwater environments of Minnesota, but whether this transformation occurs in the WWTP or bed sediment remains to be determined.

Occurrence and Fate of Selected Endocrine-Disrupting Chemicals in Water and Sediment from an Urban Lake

“…In the Pearl River system, China, average concentrations of TCS in the sediment varied from 50.5 to 693 ng g -1 (Zhao et al 2010). In sediments from Minnesota (USA) freshwater near WWTPs, TCS was detected at B85 ng g -1 , and concentrations were significantly greater from sites downstream of the WWTPs (Venkatesan et al 2012), suggesting that effluent from WWTPs is an important source of TCS. In Japanese rivers and lakes, 4-MBC was detected neither in water nor in sediment because the use of 4-MBC as an ingredient in cosmetics is not permitted in Japan, whereas BP3 was detected with concentrations B164 ng L -1 in water but not in sediment.…”

Persistence, temporal and spatial profiles of ultraviolet absorbents and phenolic personal care products in riverine and estuarine sediment of the Pearl River catchment, China

“…Significant amounts of these emerging contaminants are being discharged into the environment via treated and untreated wastewater, recreational activities, and other human activities. As a result, they have been widely detected in rivers, lakes, seas, groundwater, and organism tissues [9,[14][15][16][17][18][19][20][21][22][23][24][25][26][27].…”

Environmental risk assessment of freshwater sediments contaminated with triclosan

“…Such TCS concentration is many times higher than current environmental levels found in sediments (ranging around 0.1 to 1.3 µg g -1 in highly contaminated sites) (Zhao et al, 2010;Venkatesan et al, 2012;Sousa et al, 2015). However, such results do not imply that current environmental levels of TCS are safe to benthic aquatic organisms.…”

“…Recent studies by Perron et al (2012) and Venkatesan et al (2012) with spiked sediments, estimated the pore water concentrations based on equilibrium partitioning to determine the effective concentrations in pore water (USEPA, 1993).…”

“…Consequently, this compound is one of the major toxic organic pollutants currently found in domestic wastewaters (Farré et al, 2008). TCS is frequently found in environmental surface waters (Lindström et al, 2002;Xie et al, 2008), in sediments in ranges from pg g -1 to µg g -1 (Zhao et al, 2010;Venkatesan et al, 2012;Sousa et al, 2015), and in human breast milk (Allmyr et al, 2006;Dayan, 2007). In addition, there is some evidence that photodegradation of TCS generates dichlorodibenzo-p-dioxin (DCDD) as a byproduct (Lores et al, 2005), which further increases concern over the extensive use of this substance.…”