Environmental monitoring of alcohol sulfates and alcohol ethoxysulfates in marine sediments

Abstract

The study describes the environmental monitoring of anionic surfactants-alcohol sulfates (AS) and alcohol ethoxysulfates (AES)-in marine sediments. Concentration values were obtained after pressurised liquid extraction (PLE) and liquid chromatography-tandem mass spectrometry analysis (LC-MS/MS). Samples were collected from a range of wastewater discharge points along the coast of the provinces of Huelva, Málaga, Granada and Almería. Urban, agricultural and industrial wastewaters are discharged at the selected 38 sampling sites. Principal component analysis was carried out in order to evaluate the distribution and behaviour of these compounds in these coastal environments. Evaluation of the data revealed that the behaviour and sources of AS and AES in marine sediments are different, and that the distribution of AES depends on the length of the alkyl chain, while the number of ethoxylated units is not relevant. Additionally, the 38 sampling sites can be grouped into only two types of outfalls according to their AS distribution. The concentration of compounds in sediment samples ranged from 7.52 to 13.50 mg kg(-1) for AS, from 3.04 to 10.68 mg kg(-1) for AES-C12Ex and from 3.83 to 11.56 mg kg(-1) for AES-C14Ex.

Comprehensive review of several surfactants in marine environments: Fate and ecotoxicity

“…The amount of marine sediment monitoring data found, from highest to lowest, was AE > LAS > DTDMAC > AES > AS ( Table 1). Detected concentrations ranged from 0.0074 mg/kg to 9.19 mg/kg in AE [30], <0.003 mg/kg to 15.63 mg/kg in LAS [13,21,30,31], 0.0048 mg/kg to >25 mg/kg in DTDMAC [30], 0.061 mg/kg to 14.32 mg/kg in AES [21,[32][33][34], and 0.13 mg/kg in AS [21]. Measured concentrations in sediment were higher when sampling was undertaken in close proximity to direct discharge from sewage-treatment plant effluents, whereas samples taken from offshore locations were not impacted by direct discharge and consequently showed much lower surfactant concentration levels.…”