Effects of triclosan on marine benthic and epibenthic organisms

Abstract

Triclosan is an antimicrobial compound that has been widely used in consumer products such as toothpaste, deodorant, and shampoo. Because of its widespread use, triclosan has been detected in various environmental media, including wastewater, sewage sludge, surface waters, and sediments. Triclosan is acutely toxic to numerous aquatic organisms, but very few studies have been performed on estuarine and marine benthic organisms. For whole sediment toxicity tests, the sediment-dwelling estuarine amphipod, Ampelisca abdita, and the epibenthic mysid shrimp, Americamysis bahia, are commonly used organisms. In the present study, median lethal concentration values (LC50) were obtained for both of these organisms using water-only and whole sediment exposures. Acute 96-h water-only toxicity tests resulted in LC50 values of 73.4 and 74.3 µg/L for the amphipod and mysid, respectively. For the 7-d whole sediment toxicity test, LC50 values were 303 and 257 mg/kg (dry wt) for the amphipod and mysid, respectively. Using equilibrium partitioning theory, these whole sediment values are equivalent to interstitial water LC50 values of 230 and 190 µg/L for the amphipod and mysid, respectively, which are within a threefold difference of the observed 96-h LC50 water-only values. Triclosan was found to accumulate in polychaete tissue in a 28-d bioaccumulation study with a biota-sediment accumulation factor of 0.23 kg organic carbon/kg lipid. These data provide some of the first toxicity data for triclosan with marine benthic and epibenthic species while also indicating a need to better understand the effects of other forms of sediment carbon, triclosan ionization, and organism metabolism of triclosan on the chemical's behavior and toxicity in the aquatic environment.

Environmental risk assessment of freshwater sediments contaminated with triclosan

“…These results were more sensitive than obtained from Perron et al (2012), which showed acute toxicity of TCS spiked sediments on estuarine amphipoda Ampelisca abdita and mysid Americamysis bahia. After 7-d exposure, the lethal concentration to amphipoda A. abdita and mysid A. bahia were 303 and 257 µg g -1 , respectively.…”

“…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).…”

Use of a novel sediment exposure to determine the effects of triclosan on estuarine benthic communities

“…We calculated concentrations of 137 and 10 mg/L triclosan in the interstitial water of the highand low-triclosan-treated mesocosms, respectively. Perron et al [9] reported a 96-h water-only LC50 for the amphipod A. abdita of 73 mg/L. The low-triclosan-treated mesocosms had predicted interstitial water concentrations below A. abdita's LC50, and no difference was noted for amphipods or the benthic community between the low-triclosan and the laboratory control mesocosms.…”

“…The 96-h aqueous median lethal concentration (LC50) for Americamysis bahia (mysid) and Ampelisca abdita (amphipod) is 74 and 73 mg/L, respectively [9]. For Palaemonetes pugio (grass shrimp), the acute aqueous LC50s were 305 mg/L for adult shrimp, 154 mg/L for larvae, and 651 mg/L for embryos [10].…”

Strategies to Prevent Healthcare-Associated Infections through Hand Hygiene

“…Triclosan is a known water contaminant, and concerns persist about endocrine disruption in aquatic life, 167 which has led to inquiries about exposure levels and health effects in humans.…”