Lower chlorinated PCBs accumulate in demolition workers while working on a contaminated worksite

Area of Science:

• Environmental Health
• Occupational Health
• Toxicology

Background:

• Danish social housing estate buildings exceeded indoor air guidance values for polychlorinated biphenyls (PCBs).
• Demolition of these PCB-contaminated buildings necessitated worker exposure assessment.
• Biomonitoring is crucial for evaluating internal exposure to environmental contaminants.

Purpose of the Study:

• To evaluate the in-vivo exposure of demolition workers to all 209 PCBs during a two-year demolition project.
• To compare PCB serum concentrations and accumulation in workers at a contaminated site versus other worksites and office environments.
• To assess the effectiveness of personal protective equipment (PPE) in mitigating PCB exposure.

Main Methods:

• Biomonitoring of serum PCB concentrations in demolition workers (n=24) at a contaminated site over two years.
• Comparison of PCB levels with demolition workers at other sites (n=21) and office workers (n=17).
• Gas chromatography high-resolution mass spectrometry (GC-HRMS) used for measuring 58 different PCB congeners in serum samples.

Main Results:

• Demolition workers on the contaminated site showed a four-fold increase in lower chlorinated PCBs (tri- and tetra-CBs) after one year compared to office workers.
• Nine specific PCBs, including PCB-66/80, significantly increased from baseline to year 1 in contaminated-site workers.
• Higher chlorinated PCBs remained stable or decreased slightly, while age and lipophilicity (logKow) predicted PCB increases.

Conclusions:

• Despite provided PPE, demolition workers at PCB-contaminated sites experience significant internal exposure and accumulation of lower chlorinated PCBs.
• Occupational safety measures require careful consideration to minimize exposure risks for demolition workers in contaminated environments.
• The findings underscore the importance of biomonitoring for assessing and managing occupational exposure to persistent organic pollutants like PCBs.