道路灰尘经皮渗透 检测金属元素

The skin constitutes a protective barrier to external physical and chemical aggressions. Although it is constantly exposed to various xenobiotics, it is generally considered poorly permeable to them, as for example metal ions, becoming unfortunately an entry route of such substances. Metals may penetrate inside the skin inducing more or less local effects such as skin sensitization and potential metals diffusion into the bloodstream. The objective of the study was to investigate the percutaneous penetration of metals in vitro - ex vivo in Franz cell with intact as well damaged skin applying a road dust powder. Moreover, porcine and human skins were compared. This study demonstrated that, after the application of a road dust powder on the skin, metals can penetrate and permeate this cutaneous membrane. From this experimental analysis, in intact skin lead (Pb) achieved the highest skin absorption in both human and porcine skin, while skin absorption profile of cobalt (Co) was the lowest in human skin than the one in porcine model. The concentrations of Ni present in receiving solution were higher compared to other metals in all experiments performed. The present work, definitely shows that metals permeation through damaged skin is accelerated than intact skin, as a result of the weaker cutaneous barrier function. According to published data, pig skin appeared as a suitable model for human skin. Our results confirmed that skin absorption of metals can be relevant in environmental exposures.

… showed that the adsorption amount was the highest in dusty … and rapid absorption across the alveolar epithelium─dermal … or even higher dermal absorption capacity than inhalation. A …

… dermal toxicity, there is no published information available to confirm or refute their assumed dermal bioavailability … Inhalation of metal dust in an industrial setting has been reported to …

Dermal exposure to metal(loid)s from contaminated soils can contribute to health risk. Metal(loid) speciation will influence their bioaccessibility in sweat and subsequent permeation across the skin. Therefore, the speciation of the bioaccessible fraction of metal(loid)s in two synthetic sweat formulations (sweat A (pH 6.5) and B (pH 4.7)) was assessed using chemical equilibrium modelling (Visual MINTEQ). Permeation through synthetic skin and the influence of sebum in the permeation of As, Cr, Cu, Ni, Pb, and Zn were also investigated using Franz cells. Following dermal bioaccessibility tests for five Chromated Copper Arsenate (CCA)-contaminated soils and one certified soil (SQC001), mean metal(loid) bioaccessibility (%) was higher in sweat B (2.33-18.8) compared to sweat A (0.12-7.53). Arsenic was almost entirely found as As(V) in both sweats. In sweat A, comparable concentrations of Cr(III) and Cr(VI) were found whereas in sweat B, Cr was primarily present as Cr(III). Copper was primarily found as Cu2+. Bioaccessible Cr extracted from nearly all soils permeated through the Strat-M membrane when it was coated with sebum. The Cr permeation coefficient (Kp) ranged between 0.004 and 0.13 cm/h and the Kp for Cu was higher (0.024-0.52 cm/h). As, Ni, Pb, and Zn did not permeate the synthetic skin.

Human exposure to airborne particulate matter (PM), particularly its metal content, represents a growing public health concern due to its potential toxicological effects. While inhalation is generally considered the main exposure route, dermal absorption remains insufficiently explored. This study examined the in vitro percutaneous penetration of selected metals (As, Cd, Cr, Cu, Mn, Mo, Ni, Pb, V) from certified urban road dust (NIST SRM® 1649b) using human skin under both intact and abraded conditions. The particles were applied as a 1 % w/v suspension in artificial sweat medium (pH 4.5), and Franz diffusion cells were used to evaluate metal permeation over 24 h. Complementary solubility tests in simulated sweat solution buffered topH 4.5 and 6.5 showed negligible pH dependence. Scanning electron microscopy revealed submicron primary particles (mean diameter 1.19 ± 0.78 μm) with a high tendency to form agglomerates, accounting for discrepancies with the hydrodynamic size reported in the SRM certificate. No detectable skin absorption was observed for Cd, Cr, and Cu, while the remaining metals showed enhanced permeation in damaged skin, confirming the role of barrier disruption in facilitating transdermal transport. Ni, Pb, and Mn exhibited the highest permeation levels, raising concern due to their sensitizing and toxic potential. These findings provide novel insights into the dermal bioavailability of PM-associated metals and highlight the importance of including skin exposure as a relevant pathway in environmental health risk assessments, especially for populations with compromised skin integrity or in high-exposure occupational settings.

The human health risk assessment through the dermal exposure of metal(loid)s in dust from low latitude and high geological background plateau cities was largely unknown. In this study, the road dust samples were harvested from a typical low-latitude plateau provincial capital city Kunming, Southwest China. The total concentration and dermal bioaccessibility of heavy metal(loid)s in road dust were determined, and their health risks and cytotoxicity on human skin keratinocytes were also assessed. The average concentrations of As (28.5 mg/kg), Cd (2.65 mg/kg), Mn (671 mg/kg), and Zn (511 mg/kg) exceeded the soil background values. Arsenic had the highest bioaccessibility after 2 h (3.79%), 8 h (4.24%), and 24 h (16.6%) extraction. Although soil assessment methods showed no health risk in the total heavy metals assessment, based water assessments showed bioaccessible heavy metals As, Mn, Ni and Cd have non-carcinogenic risks for human. In addition, the dust extracts suppressed the cell viability, increased the Reactive oxygen species (ROS) level and DNA damage, and eventually activated the mitochondria-mediated apoptosis pathway, evidenced by the upregulation of Caspase-3/9, Bax, and Bak-1. Cadmium was positively correlated with the mRNA expression of Bax. Both dermal bioaccessibility and cytotoxicity should be considered for accurate human skin health risk assessment of heavy metals in road dust, which may provide new insight for accurate human health risk assessment and environmental management.

… street dusts were all higher than the local soil background values. The concentrations of heavy metals … carcinogenic and carcinogenic risks of the metals for inhabitants. However, higher …

The objective of this study was to investigate the concentration and spatial distribution patterns of 9 potentially toxic heavy metal elements (As, Cd, Co, Cr, Pb, Cu, Zn, Mn, and Ni) in road dust in the Bayan Obo Mining Region in Inner Mongolia, China. Contamination levels were evaluated using the geoaccumulation index and the enrichment factor. Human health risks for each heavy metal element were assessed using a human exposure model. Results showed that the dust contained significantly elevated heavy metal elements concentrations compared with the background soil. The spatial distribution pattern of all tested metals except for As coincided with the locations of industrial areas while the spatial distribution of As was associated with domestic sources. The contamination evaluation indicated that Cd, Pb, and Mn in road dust mainly originated from anthropogenic sources with a rating of “heavily polluted” to “extremely polluted,” whereas the remaining metals originated from both natural and anthropogenic sources with a level of “moderately polluted”. The non-cancer health risk assessment showed that ingestion was the primary exposure route for all metals in the road dust and that Mn, Cr, Pb, and As were the main contributors to non-cancer risks in both children and adults. Higher HI values were calculated for children (HI=1.89), indicating that children will likely experience higher health risks compared with adults (HI=0.23). The cancer risk assessment showed that Cr was the main contributor, with cancer risks which were 2–3 orders of magnitude higher than those for other metals. Taken in concert, the non-cancer risks posed by all studied heavy metal elements and the cancer risks posed by As, Co, Cr, Cd, and Ni to both children and adults in Bayan Obo Mining Region fell within the acceptable range.

In this study, we assessed the health risks of particulate-bound metals arsenic (As), mercury (Hg), chromium (Cr), cobalt (Co), nickel (Ni), and zinc (Zn) in PM₂.₅, PM₁₀, and road dust samples collected from eight urban areas in Greater Noida, India. The highest concentrations were observed for As (1.40 ± 0.77 mg∙kg -1 ) and Hg (0.58 ± 0.29 mg∙kg -1 ) in road dust. The health risk assessment revealed that the non-carcinogenic hazard index (HI) values ​​were greater than 1.0 for both adults and children, suggesting potential adverse health effects. The carcinogenic risk values ​​for As, Cr, and Co exceeded the permissible limit of 1×10⁻⁴ in some samples, with the highest observed value being 3.98×10 2 for PM₁₀ exposure in adults, well above the permissible risk range (1×10⁻⁶–1×10⁻⁴). Source apportionment analysis showed that the main sources were vehicle emissions, fuel combustion, and wear of brake and tyre components. The results highlight the urgent need for regulatory action to mitigate heavy metal exposure in urban environments.