Laboratory investigation of inadvertently generated PCBs released from consumer products into lake water

Polychlorinated biphenyls (PCBs), though heavily restricted in many countries, continue to be detected in modern environments due to inadvertent production methods such as pigment manufacturing. This study investigates the occurrence and leaching behavior of inadvertently generated PCBs (iPCBs) in consumer products including children's toys, craft supplies, paints, soaps, and food packaging. Product selection prioritized items used by children and tribal communities, where PCB exposure risks are of heightened concern. Using solvent extraction, sample cleanup processes, and gas chromatography/mass spectrometry analysis, 37-4268 ng g^-1 of PCB-11 was detected in seven of 114 product types tested and a total of 21 respective color variants. Highest concentrations were found in items containing orange pigments, supporting hypotheses linking PCB-11 to azo pigment synthesis. To assess environmental release potential, batch leaching tests were performed in the laboratory on four representative products across various leach durations (2-28 days) and liquid-to-solid (L/S) ratios (6.7-26.7 mL g^-1). Results showed that < 10 % of total PCB mass leached into lake water under all conditions, with most remaining sorbed to solids. Foam materials such as glitter foam exhibited notably low leaching across all scenarios, likely due to hydrophobic, porous matrices. Leaching rate and extent was influenced by matrix properties, leach duration, and L/S ratio, with more pronounced release from fiberboard and wax-based matrices. These findings enhance understanding of inadvertent PCB sources in consumer goods and their environmental behavior and underscore the importance of considering product composition in exposure assessments and future risk management decisions.