Polyoxymethylene passive samplers to monitor changes in bioavailability and flux of PCBs after activated carbon amendment to sediment in the field

► Activated carbon was amended to river sediments in the field. ► Amendment reduced bioavailability and flux of PCBs. ► Activated carbon treated sediments acted as a sink for PCBs from the water column. ► Reduced uptake of PCBs in passive samplers trended with uptake in invertebrates. ► Passive samplers are suited for monitoring bioavailability change after remediation.