Global distribution and local impacts of inadvertently generated polychlorinated biphenyls in pigments

The non-Aroclor congener 3,3'-dichlorobiphenyl (PCB 11) has been recently detected in air, water, sediment, and biota. It has been known since at least the 1970s that this congener is produced inadvertently during the production of certain organic pigments. PCB 11 was previously measured at parts-per-billion (ppb) levels in various printed materials obtained in the US. In this work, PCB 11 was detected in samples of common consumer goods including magazines, advertisements, maps, postcards, brochures, napkins, and garments from 26 countries in five continents at concentrations ranging from 0.27 to 86 ppb. Leaching tests confirmed that PCB 11 could be released from these materials into water. We also examined whether the known sources of PCB 11 were large enough to account for the levels of PCB 11 measured in the air, water, soil and sediment of the Delaware River Basin. A mass flow analysis suggests that the outflows and sequestration of PCB 11 in the basin total between 30 and 280 kg y(-1). If PCB 11 concentrations in pigments were at the maximum average (125 ppm) allowed under the Toxic Substances Control Act (TSCA), the estimated input of PCB 11 to the Delaware River Basin would be on the order of 42 kg y(-1). Despite the large uncertainty in these numbers, the results suggest that pigments may plausibly account for the levels of PCB 11 measured in the environment.