Abstract: In order to explore the transport of persistent organic pollutants (POPs) in the industrial process, polychlorinated biphenyls (PCBs), including seven indicator congeners and CB-209, were investigated in the spent etching solutions generated during manufacture of printed circuit boards and its copper salt recycling products. The potential of PCB transport from the spent etching solutions to the copper salts was discussed as well. The samples, including three different spent etching solutions, H₂SO₄ and three kinds of copper salts, were analyzed by high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS) using an isotope-dilution method. The results showed that no evident PCBs were detected in the spent alkaline etching solutions and microetch solutions, while various levels of the contaminants were found in the spent acid etching solutions. ρ(∑₈PCBs) were in the range of 0.41-60.80 ng/L, where ρ(∑₇PCBs) of the indicator congeners ranged from 0.24-58.00 ng/L. Among the copper salts (CuCl₂, Cu₂(OH)₃Cl and CuSO₄), relatively higher levels of PCBs were observed in CuSO₄ samples, with w(∑₈PCBs) of 2.75-284.00 ng/kg, while w(∑₈PCBs) in CuCl₂ and Cu₂(OH)₃Cl ranged between 6.95-31.50 ng/kg and 7.31-9.42 ng/kg, respectively. The congener profiles showed a similar distribution pattern of PCBs in the spent acid etching solutions and its copper recycling products, where CB-28 was the predominant congener and followed by CB-209. Since CB-209 was not present in the most common Aroclor mixtures and rarely found in the environment, higher levels of CB-209 combined with the similar profiles of indicator PCBs in both spent acid etching solutions and its copper recycling products suggested that PCBs in the copper salts might be mainly transported from the spent acid etching solutions. It is necessary to further investigate the source in spent acid etching solutions.