Partitioning and accumulation rates of polycyclic aromatic hydrocarbons into polydimethylsiloxane thin films and black worms from aqueous samples

Abstract

Partition equilibriums and extraction rates of polycyclic aromatic hydrocarbons (PAHs) were examined for live biomonitoring with oligochaetes (black worms, Lumbriculus variegatus) and for high surface area chemical passive samplers constructed from polydimethylsiloxane thin film. The goals were to better understand the principles of bioconcentration by aquatic organisms and to aid in the design of a convenient and simple chemical monitoring tool to replace the use of live animals. The worms and films were exposed simultaneously to the contaminated water stream. In the initial extraction stage, similar extracted amount per surface area indicated that thin-film samplers could mimic the behavior of worms for passive sampling. Equilibrium was reached faster by the thin films than by the worms. A good linear relationship between the bioconcentration factors and the film–water partition coefficients of PAHs was found, which demonstrated the feasibility of thin-film sampler for determining the bioavailability of PAHs in water. Compared to the lengthy and inconvenient process of liquid–liquid extraction in worm treatment, thin-film technique simplifies the sample pretreatment procedure by integrating sampling and sample preparation.