title: Effects of triclosan on aquatic invertebrates in tropics and the influence of pH on its toxicity on microalgae.
abstract: The antimicrobial triclosan (TCS) has been detected in household wastewaters (untreated and treated) and receiving environments across the globe. The toxic effects of TCS on temperate standard aquatic test organisms have been widely reported with microalgae being the most sensitive. However, environmental differences between tropical and temperate regions may have selected different trait compositions between these two regions, which in turn may lead to a difference in species sensitivity. Therefore, additional information is required to better characterize risks to organisms in tropics and ensure biodiversity in these regions is not adversely impacted. This study aims to supplement existing TCS toxicity data with five aquatic invertebrates found in tropics and to compare the sensitivity between aquatic invertebrate species from tropical and temperate regions. In addition, the effect of pH on the toxicity of neutral and ionized forms of TCS to microalgae (Chlorella ellipsoidea) was investigated. The reported 96-h LC50 values for the studied invertebrate species ranged from 72 to 962 μg/L. There was no significant difference between the sensitivity of aquatic invertebrate species from tropical and temperate regions. EC50 values for C. ellipsoidea, with and without pH buffer, were significantly different. The findings of this study can be used to support site-specific water quality criteria and environmental risk assessment for TCS in tropical regions. However, further chronic and semi-field experiments with TCS could potentially enable a refined assessment of direct and indirect effects on tropical aquatic communities and further explore functional endpoints of tropical ecosystems.
authors.affiliation: Department of Aquatic Ecology and Water Quality Management, Wageningen University, P.O. Box 47, 6700 AA, Wageningen, The Netherlands. jidapa.khatikarn@wur.nl.|Department of Fishery Biology, Faculty of Fisheries, Kasetsart University, Chatuchak, Bangkok, 10900, Thailand. jidapa.khatikarn@wur.nl.
authors.forename: Jidapa
authors.initials: J
authors.lastname: Khatikarn
authors.affiliation: Department of Fishery Biology, Faculty of Fisheries, Kasetsart University, Chatuchak, Bangkok, 10900, Thailand.
authors.forename: Kriengkrai
authors.initials: K
authors.lastname: Satapornvanit
authors.affiliation: Safety and Environmental Assurance Centre, Unilever, Colworth Science Park, Sharnbrook, MK44 1LQ, Bedfordshire, UK.
authors.forename: Oliver R
authors.initials: OR
authors.lastname: Price
authors.affiliation: Department of Aquatic Ecology and Water Quality Management, Wageningen University, P.O. Box 47, 6700 AA, Wageningen, The Netherlands.|Alterra, Wageningen University and Research Centre, P.O. Box 47, 6700 AA, Wageningen, The Netherlands.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Van den Brink
mesh_terms: D000818:Animals; D059001:Aquatic Organisms / Q000187:drug effects*; D002708:Chlorella / Q000187:drug effects*; D004781:Environmental Exposure; D006863:Hydrogen-Ion Concentration; D007448:Invertebrates / Q000187:drug effects*; D018570:Risk Assessment; D018675:Toxicity Tests; D014260:Triclosan / Q000633:toxicity*; D014329:Tropical Climate; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D060753:Water Quality / Q000592:standards
chemical_list: D014874:Water Pollutants, Chemical; D014260:Triclosan
keywords: Acute toxicity; Antimicrobial; Aquatic; Invertebrates; Triclosan; Tropics; pH