Abstract
A polar organic chemical integrative sampler (POCIS) was developed for the detection of linear alkylbenzene sulfonates (LASs), which are one of the most widely used chemicals globally and represent a type of surfactant agent. Owing to natural disasters and accidents, these LASs have a potential risk to leak into aquatic environments at high concentrations, and thus far, passive sampling methods have not yet been applied in their detection as, being a sorptive compound, they do not easily permeate the membrane of passive samplers. In the present study, the LASs were significantly sorbed onto the polyethersulfonate (PES) membrane, suggesting that the less sorptive polytetrafluoroethylene (PTFE) membrane is suitable for application in the POCIS device. Calibration experiments showed that the developed POCIS device with Oasis WAX as the sorbent and PTFE as the membrane filter had linear ranges > 28 d and sampling rates ranging from 0.035 ± 0.007 (tetradecylbenzenesulfonate) to 0.139 ± 0.024 (dodecylbenzenesulfonate) L d–1. Furthermore, this developed POCIS device was validated under non-steady-state conditions via both chamber and field tests. The condition in the chamber test replicated the LAS concentration change in rivers contaminated by LAS-leaked accidents. The time-weighted average concentrations of dodecylbenzenesulfonate measured using the improved POCIS agreed well with those obtained via grab sampling within 21% over the sampling period of 14 d in both the chamber and field tests. Therefore, the developed POCIS can be successfully applied in the detection of LASs in LAS-contaminated aquatic environments owing to chemical leak accidents.