The availability of polycyclic aromatic hydrocarbons (PAHs) from marine sediments to the ragworm (Nereis virens) was studied. Concentrations of PAHs in pore waters were determined using silicone rubber passive samplers. Calculated bioconcentration factors confirmed that partitioning of PAHs between the lipid phase of the polychaetes and pore water is a passive process. Low biota-sediment accumulation factors (BSAF) calculated using total sediment concentration suggested a fraction of the total PAH burden in the sediment may be strongly sorbed to organic carbon and not available to the polychaete. Organic carbon normalised concentrations of the potentially exchangeable fractions of contaminants and freely dissolved concentrations (measured using silicone rubber samplers) provide a better description of the observed bioaccumulation by the ragworms. These data indicate that the concept of availability should be included in environmental risk assessments based upon equilibrium partitioning models, and that silicone rubber samplers can provide the necessary information for these models. Copyright © 2011 Elsevier Ltd. All rights reserved.