Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, 510275, PR China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China.
Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA, 01003, USA.
Environ Pollut. 2018 Nov;242(Pt B):1669-1677. doi: 10.1016/j.envpol.2018.07.109. Epub 2018 Jul 26.
We describe a batch-extraction with simulated digestive fluid (salivary fluid, gastric fluid and intestinal fluid) to estimate the bioaccessibility of inhaled trace metals (TMs) in particulate matter less than 10 and 2.5 μm in aerodynamic diameter (PM and PM). Concentrations of the assayed TMs (As, Cd, Cr, Ni, Mn, Cu, Zn, Sb, Hg and Pb) were determined in PM and PM samples by inductively coupled plasma-mass spectrometry. The TMs with the largest soluble fractions for airborne PM collected from winter and summer in saliva were Mn and Sb, respectively; in seasons this became Co in gastric fluid and Cu in intestinal fluid. Clearly, bioaccessibility is strongly dependent on particle size, the component of simulated digestive fluids (e.g., pH, digestive enzymes pepsin and trypsin), and the chemical properties of metal ions. The particle size and seasonal variation affected the inhaled bioaccessible fraction of PM-bound TMs during mucociliary clearance, which transported PM from the tracheal and the bronchial region to the digestive system. This study provides direct evidence for TMs in airborne PM being bioaccessible TMs are likely to possess an enhanced digestive toxic potential due to airborne PM pollution.
我们描述了一种批量提取方法，使用模拟消化液（唾液、胃液和肠液）来估计吸入性小于 10μm 和 2.5μm 空气动力学直径（PM 和 PM）的颗粒态痕量金属（TMs）的生物可给性。采用电感耦合等离子体质谱法测定了 PM 和 PM 样品中测定的 TMs（As、Cd、Cr、Ni、Mn、Cu、Zn、Sb、Hg 和 Pb）的浓度。从冬季和夏季空气中采集的 PM 中 Mn 和 Sb 的可溶分数最大，而在胃液中 Co 最大，在肠液中 Cu 最大。显然，生物可给性强烈依赖于颗粒大小、模拟消化液的成分（例如，pH 值、胃蛋白酶和胰蛋白酶等消化酶）以及金属离子的化学性质。颗粒大小和季节变化影响了黏液纤毛清除过程中 PM 结合 TMs 的吸入生物可给分数，该过程将 PM 从气管和支气管区域输送到消化系统。这项研究为空气中 PM 中的 TMs 是生物可给的 TMs 提供了直接证据，由于空气中 PM 污染，这些 TMs 可能具有增强的消化毒性潜力。
