Measuring bioavailable PAHs in estuarine water using semipermeable membrane devices with performance reference compounds

Bioavailable polycyclic aromatic hydrocarbon (PAH) concentrations in the estuarine water of Kaohsiung Harbor were measured using XAD-2 resin and semipermeable membrane devices (SPMDs) calibrated with performance reference compounds (PRCs). The sum of the PAH concentrations from XAD-2 resin (C_w) in the surface and bottom water samples was 6.63 and 9.58ngL^{- 1}, respectively. The variation in PAHs was higher in surface water. Cubic polynomial regressions using the sampling rate for five PRCs (R_{s -PRC}) provided estimated in situ sampling rates (R_s). The turbulent condition in the surface water was important in enhancing R_s; however, diffusion was relevant to the bottom water, which was less turbulent and showed decreasing R_s at high MW PAHs. The sum of the dissolved PAH concentrations estimated with the SPMDs (C_SPMD) was 5.87 and 9.15ngL^{- 1} in the surface and bottom water samples, respectively. The surface and bottom water PAHs were derived from different sources.