Occurrence, fate and environmental risk of linear alkylbenzene sulfonate in the Langat and Selangor River basins, Malaysia

• Published in: Chemosphere Vol. 172; pp. 234 - 241
• Main Authors: Sakai, Nobumitsu, Shirasaka, Junichi, Matsui, Yasuto, Ramli, Mohd Redzuan, Yoshida, Kousuke, Ali Mohd, Mustafa, Yoneda, Minoru
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.04.2017; Elsevier BV
• Subjects: adsorption; Alkanesulfonic Acids; Alkanesulfonic Acids - analysis; Alkanesulfonic Acids - toxicity; ammonium nitrogen; biodegradation; Chromatography, Liquid; environmental fate; Environmental fate and risk assessment; Environmental Monitoring; Environmental Monitoring - methods; Geographic Information Systems; GIS; Langat and Selangor River basins; LC-MS/MS; Linear alkylbenzene sulfonate; liquid chromatography; Malaysia; particle size; population density; Quantitative Structure-Activity Relationship; quantitative structure-activity relationships; risk; Risk Assessment; Rivers; Spatial Analysis; Spatial analysis and source profiling; surface water; Surface-Active Agents; Surface-Active Agents - analysis; Surface-Active Agents - toxicity; Tandem Mass Spectrometry; Water Pollutants, Chemical; Water Pollutants, Chemical - analysis; Water Pollutants, Chemical - toxicity; watersheds; Malaysia; GIS; Spatial analysis and source profiling; LC-MS/MS; Linear alkylbenzene sulfonate; Langat and Selangor River basins; Environmental fate and risk assessment
• DOI: 10.1016/j.chemosphere.2016.12.139
• ISSN: 0045-6535

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. [Display omitted] •LAS contamination was correlated with population density and ammonia nitrogen.•Environmental fate was subject to suspended solids rather than biodegradation.•Longer alkyl chain lengths were more absorbed to large suspended solids (>11 μm).•LAS concentration at 3 sub-basins was over predicted no effect concentrations.•Environmental risk areas and susceptible areas due to LAS were spatially identified.