Citation:

Weitekamp, C., L. Phillips, L. Carlson, N. DeLuca, E. Hubal, AND G. Lehmann. A state-of-the-science review of polychlorinated biphenyl exposures at background levels: relative contributions of exposure routes. SCIENCE OF THE TOTAL ENVIRONMENT. Elsevier BV, AMSTERDAM, Netherlands, 776:1-8, (2021).

Impact/Purpose:

The commercial manufacture of polychlorinated biphenyls (PCBs) was banned in the United States in 1979, yet PCBs continue to be detected in most samples of human blood and breast milk. Dietary exposure from intake of PCB contaminated fatty foods is often considered the primary source of the human body burden of PCBs. However, several studies suggest that, in some contexts, inhalation exposure levels can be comparable to or even higher than dietary exposures. Here, we estimated the relative contribution of different PCB exposure pathways for the general population, including dietary intake, inhalation, dermal contact, and ingestion of dust and soils. In general, our review identifies important limitations in the data available to assess population exposures, highlighting the need for more current and population-based estimates of PCB exposure, particularly for indoor air and dietary intake. Communication of these uncertainties to the research community could help to further the collection of data essential to the improvement of risk assessment and risk management of PCBs. In addition, our estimates of population exposure may be of interest to both regional partners and the public.

Description:

Background: Exposure to polychlorinated biphenyls (PCBs) can occur through multiple routes and sources, including dietary intake, inhalation, dermal contact, and ingestion of dust and soils. Dietary exposure to PCBs is often considered the primary exposure route for the general population, however, recent studies suggest an increasing contribution from indoor inhalation exposure. Objectives: Here, we aim to estimate the relative contribution of different PCB exposure pathways for the general population, as well as for select age groups. Methods: We conducted a targeted literature review of PCB concentrations in environmental media, as well as of total dietary intake. Using the average concentrations from the studies identified, we estimated PCB exposure through different routes for the general population. In addition, we assessed exposure via environmental media for select age groups. Results: We identified 64 studies that provided background PCB concentrations for one or more of the environmental media of interest and 6 studies that provided estimates of total dietary intake. Using estimates from studies conducted worldwide, for the general population, dietary intake of PCBs was the major exposure pathway. Discussion: In general, our review identifies important limitations in the data available to assess population exposures, highlighting the need for more current and population-based estimates of PCB exposure, particularly for indoor air and dietary intake.

Record Details: