PCBs in processes, products and environment of paper mills using wastepaper as their raw material

The occurrence of PCBs in raw materials, processes, products and environmental samples were analysed with the aim of resolving the sources and pathways of PCBs in the processes and environment of paper mills producing recycled paper products. In the wastepaper grades examined, PCBs were observed only in archival paper (0.47-1.0 mg/kg). In the deinking process, PCBs were observed in deinking sludge, but it was not observed in pulper stock, recycled fibre pulp, tissue paper reject or process waters. In deinking sludge, PCBs were mainly observed in samples from a pulper that used wastepaper from offices as its raw material. Between 1993 and 2002 PCB concentrations in the latter decreased from 1.3 mg/kg to 0.14 mg/kg. PCBs were also observed in the wastewater treatment plant in sludge, but not in wastewater. Between 1993 and 2004 concentrations in biosludge decreased from 0.56 mg/kg to 0.13 mg/kg. The PCB fingerprint in raw material and process samples corresponded to the fingerprint from Aroclor 1242. The greater proportion of recycled paper products did not contain PCBs. Low concentrations of PCB were however observed in hand towel sheet (0.02-0.07 mg/kg) and toilet tissue (0.02-0.14). The PCB fingerprint in the recycled paper products corresponded to the fingerprint from Aroclor 1242. The PCB concentrations in pike (Esox lucius) caught in Lake Melasjärvi, a small lake basin downstream from the Mänttä mill an