Fig. 3. Mass of fluoranthene and pyrene-d₁₀ (Nf) thermally desorbed from the porewater sampler (fitted with a 100mm PDMS-coated SPME fiber) vs. exposure time to estuarine sediment spiked with ~300 ng/g fluoranthene and other target analytes. Pyrene-d₁₀ was pre-loaded into the SPME fiber prior to exposure.