title: Occurrence, fate and environmental risk of linear alkylbenzene sulfonate in the Langat and Selangor River basins, Malaysia.
abstract: Five homologs (C10-C14) of linear alkylbenzene sulfonate (LAS) were quantitated in surface water collected in the Langat and Selangor River basins using liquid chromatography-tandem mass spectrometry (LC-MS/MS). A geographic information system (GIS) was used to spatially analyze the occurrence of LAS in both river basins, and the LAS contamination associated with the population was elucidated by spatial analysis at a sub-basin level. The LAS concentrations in the dissolved phase (<0.45 μm) and 4 fractions separated by particle size (<0.1 μm, 0.1-1 μm, 1-11 μm and >11 μm) were analyzed to elucidate the environmental fate of LAS in the study area. The environmental risks of the observed LAS concentration were assessed based on predicted no effect concentration (PNEC) normalized by a quantitative structure-activity relationship model. The LAS contamination mainly occurred from a few populated sub-basins, and it was correlated with the population density and ammonia nitrogen. The dissolved phase was less than 20% in high contamination sites (>1000 μg/L), whereas it was more than 60% in less contaminated sites (<100 μg/L). The environmental fate of LAS in the study area was primarily subject to the adsorption to suspended solids rather than biodegradation because the LAS homologs, particularly in longer alkyl chain lengths, were considerably absorbed to the large size fraction (>11 μm) that settled in a few hours. The observed LAS concentrations exceeded the normalized PNEC at 3 sites, and environmental risk areas and susceptible areas to the LAS contamination were spatially identified based on their catchment areas.
authors.affiliation: Division of Environmental Engineering, Graduate School of Engineering, Kyoto University, Kyoto 615-8540, Japan; Shimadzu-UMMC Centre of Xenobiotic Studies, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia. Electronic address: sakai@risk.env.kyoto-u.ac.jp.
authors.forename: Nobumitsu
authors.initials: N
authors.lastname: Sakai
authors.affiliation: Division of Environmental Engineering, Graduate School of Engineering, Kyoto University, Kyoto 615-8540, Japan.
authors.forename: Junichi
authors.initials: J
authors.lastname: Shirasaka
authors.affiliation: Division of Environmental Engineering, Graduate School of Engineering, Kyoto University, Kyoto 615-8540, Japan.
authors.forename: Yasuto
authors.initials: Y
authors.lastname: Matsui
authors.affiliation: Shimadzu-UMMC Centre of Xenobiotic Studies, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.
authors.forename: Mohd Redzuan
authors.initials: MR
authors.lastname: Ramli
authors.affiliation: Lion Corporation, 100 Tajima, Odawara-shi, Kanagawa 256-0811, Japan.
authors.forename: Kousuke
authors.initials: K
authors.lastname: Yoshida
authors.affiliation: Shimadzu-UMMC Centre of Xenobiotic Studies, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Ali Mohd
authors.affiliation: Division of Environmental Engineering, Graduate School of Engineering, Kyoto University, Kyoto 615-8540, Japan.
authors.forename: Minoru
authors.initials: M
authors.lastname: Yoneda
mesh_terms: D017738:Alkanesulfonic Acids / Q000032:analysis* / Q000633:toxicity; D002853:Chromatography, Liquid; D004784:Environmental Monitoring / Q000379:methods*; D040362:Geographic Information Systems; D008296:Malaysia; D021281:Quantitative Structure-Activity Relationship; D018570:Risk Assessment; D045483:Rivers; D062206:Spatial Analysis; D013501:Surface-Active Agents / Q000032:analysis / Q000633:toxicity; D053719:Tandem Mass Spectrometry; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000633:toxicity
chemical_list: D017738:Alkanesulfonic Acids; D013501:Surface-Active Agents; D014874:Water Pollutants, Chemical; C030641:alkylbenzyl sulfonic acid
keywords: Environmental fate and risk assessment; GIS; LC-MS/MS; Langat and Selangor River basins; Linear alkylbenzene sulfonate; Spatial analysis and source profiling