School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou, 510006, China.
State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China.
Environ Sci Pollut Res Int. 2021 Nov;28(44):62133-62141. doi: 10.1007/s11356-021-14848-9. Epub 2021 Jun 29.
Bioavailability of environmental contaminants is attracting considerable scientific attention due to growing awareness of its importance for risk assessment. In this study, size-segregated airborne particles were collected from six point-source sites, an urban residential site, and a sub-urban site. Potential factors governing bioaccessibility of the particle-bound polycyclic aromatic hydrocarbons (PAHs) and organophosphorus esters (OPEs) in stimulated gastrointestinal and respiratory tracts were elucidated. Particle concentrations of PAHs and OPEs at the eight sites were 2.4-32.3 ng/m and 1.6-19.9 ng/m, respectively. In fine particles (with aerodynamic diameter less than 2.5 μm), 4- to 6-ring PAHs were more strongly correlated with organic carbon (OC) than elemental carbon (EC); while 3- and 4-ring PAHs in coarse particles (2.5-10 μm) tended to associate with EC. OPEs mostly showed significant correlations with EC in both fine and coarse particles. OC and EC exerted a significantly restraining effect on the oral and inhalation bioaccessibility of most hydrophobic organic contaminants (HOCs) in fine particles due to sorption of HOC molecules to these components. Furthermore, the effects varied, which could depend either on the emission sources (for oral bioaccessibility of PAHs) or the physicochemical properties of HOCs (for bioaccessibility of OPEs and inhalation bioaccessibility of PAHs). Linear regression between OC/EC contents and HOC bioaccessibility indicated that EC should play a more important role in the inhalation bioaccessibility than the oral bioaccessibility. Particle size of airborne particles is a relatively less significant factor determining the bioaccessibility.
环境污染物的生物可利用性正引起科学界的极大关注，因为人们越来越意识到它对于风险评估的重要性。在本研究中，从六个点源场所、一个城市居民区和一个郊区场所采集了按粒径分级的空气颗粒物。阐明了控制呼吸道和胃肠道中颗粒物结合多环芳烃（PAHs）和有机磷酯（OPEs）生物可利用性的潜在因素。八个地点的 PAHs 和 OPEs 颗粒物浓度分别为 2.4-32.3ng/m 和 1.6-19.9ng/m。在细颗粒物（空气动力学直径小于 2.5μm）中，4-6 环 PAHs 与有机碳（OC）的相关性强于元素碳（EC）；而粗颗粒物（2.5-10μm）中的 3-4 环 PAHs 则倾向于与 EC 相关。OPEs 在细颗粒和粗颗粒中主要与 EC 呈显著相关。由于 HOC 分子对这些成分的吸附，OC 和 EC 对细颗粒物中大多数疏水性有机污染物（HOCs）的口服和吸入生物可利用性产生了显著的抑制作用。此外，这种影响因排放源（对于 PAHs 的口服生物可利用性）或 HOCs 的物理化学性质（对于 OPEs 的生物可利用性和 PAHs 的吸入生物可利用性）而异。OC/EC 含量与 HOC 生物可利用性之间的线性回归表明，EC 在吸入生物可利用性中比口服生物可利用性中应发挥更重要的作用。空气颗粒物的粒径是决定生物可利用性的一个相对不太重要的因素。
