Polyurethane Foam Wristbands as Personal Passive Samplers of Ambient Particulate Exposures to Lead and Other Metals

Wearable wristband passive samplers are a tool for evaluating personal exposures to chemical mixtures such as semivolatile organic compounds. However, these samplers are ineffective for particulate-bound chemicals such as metals because they do not accumulate enough particles for analysis. Here, we sought to broaden the sampling to include metals by incorporating polyurethane foam (PUF) into a wearable wristband. We asked study participants (n = 82), recruited in two cohorts, to wear the wristband for five consecutive days. We also collected floor dust wipes, vacuumed dust, soil, and water from participants' homes and collected whole blood for analysis. Metal contents (Pb, Cu, Mn, and Fe) in the PUF positively correlated with respective metal levels in dust wipes (e.g., Spearman rho = 0.54, p < 0.0001 for Pb). Pb levels in PUF wristbands and floor wipes were not strongly predictive of blood Pb levels, suggesting that participants experienced multiple routes of exposure (e.g., dust, water, diet) that were not fully captured by the PUF wristband. The levels of Pb and Cu, normalized to Fe, were lower in soil compared to the other environmental samples, indicating that particles on the PUF were similar to those in indoor dust rather than outdoor sources. Overall, these results suggest that the addition of PUF to the wristband provides a surface for particle deposition, enabling personalized assessments of ambient metal exposures with increased sensitivity relative to dust wipes.