Preliminary assessment on exposure of four typical populations to potentially toxic metals by means of skin wipes under the influence of haze pollution

- PTMs in dust adhered on human hands were determined by means of skin wipes.
- PTM occurrence varied among populations and was influenced by haze level, gender and individual behavior patterns.
- Ground dust was deduced to be the dominant exposure source of PTMs on hands for children.
- Human exposure to PTMs in dust particles via dermal contact and ingestion were assessed.

To investigate the exposure risk of human beings to nine potentially toxic metals (PTMs), namely, Cu, Cr, Zn, As, Cd, Pb, Ni, Mn, and Co, skin wipe samples were collected from four types of populations, namely, children, undergraduates, security guards, and professional drivers, under different haze pollution levels in Xinxiang, China by using Ghost wipes. The Ghost wipes were quantitatively analyzed by inductively coupled plasma mass spectrometry (ICP-MS) after microwave digestion. Generally, Zn (ND-1350 μg/m2 for undergraduates, ND-2660 μg/m2 for security guards, ND-2460 μg/m2 for children, and ND-2530 μg/m2 for professional drivers) showed the highest concentration among the four populations, followed by Cu (0.02-83.4 μg/m2 for undergraduates, ND-70.2 μg/m2 for security guards, 23.2-487 μg/m2 for children, and ND-116 μg/m2 for professional drivers). As (ND-5.7 μg/m2 for undergraduates, ND-2.3 μg/m2 for security guards, ND-21.1 μg/m2 for children, and ND-11.0 μg/m2 for professional drivers) and Co (ND-6.0 μg/m2 for undergraduates, ND-7.9 μg/m2 for security guards, ND-13.4 μg/m2 for children, and ND-2.1 μg/m2 for professional drivers) showed the lowest concentrations in all populations. Remarkable differences were found among the four populations and PTM levels decreased in the following order: children, professional drivers, security guards, and undergraduates. Gender variation was discovered for undergraduates and children. Generally, PTM contamination in skin wipes collected during a light haze pollution level was generally higher than that during a heavy haze pollution level, but PTM contamination was comparable between the two haze pollution levels for children. Non-carcinogenic exposure risks to As, Cd, and Pb for all populations were higher than those for the other six elements but all of them were within the acceptable safety threshold, indicating no apparent non-carcinogenic risk.

The concentration of nine PTMs in light haze pollution is higher than that of heavy haze pollution.94