城区飞散致敏花粉与大气细/超细颗粒物的协同生物效应研究

城市大气颗粒物污染和致敏花粉的污染已经对人群健康和城市空气质量产生了较为严重的影响.这2种污染物的协同生物效应正在成为大气环境科学、环境毒理学、免疫学等学科研究的前沿和热点研究领域.以上海大气中的细/超细颗粒物和日本关东地区致敏花粉(柳杉)为例,阐述了大气细/超细颗粒物的表征以及花粉致敏的过程.在研究中,观察到了日本柳杉花粉壁附着有直径0.7μm的含变应原蛋白的微粒(Ubisch body),并用ELISA法揭示了日本关东地区大气颗粒物中含变应原蛋白的颗粒主要分布在1μm的粒径范围内;而在上海大气颗粒物中,化学元素总量的最大值出现在细/超细粒径颗粒物(0.3～0.18μm)范围,污染元素S和Pb的质量浓度在超细(纳米尺度)/细颗粒物中比在其他粒径范围颗粒物中要高,另外还发现在上海大气颗粒物中有植物花粉的存在.城市大气颗粒物中的主要组分,柴油机车尾气颗粒物(DEPs)与飞散花粉之间存在协同生物效应,但其机制和过程还不清楚,在最新研究成果的基础上并结合国内外相关研究领域的进展,对飞散花粉与大气细/超细颗粒物的协同生物效应的研究进行了总结并提出今后研究的方向.

Perspectives on Synergic Biological Effects Induced by Ambient Allergenic Pollen and Urban Fine/Ultrafine Particulate Matters in Atmosphere

Ambient particulate matters (PM) and allergenic pollens in urban atmosphere have taken negative effects on human health and air quality. Studies on synergistic effects between the two pollutants are being focused in disciplines, such as atmospheric sciences, environmental toxicology, and immunology. In this study, physicochemical characterization of airborne fine/ultrafine particles in Shanghai, China and ambient allergenic pollens (cedar) in Kanto, Japan were investigated. We found that allergenic protein particles (Ubisch body) with diameter less than 0.7 microm were absorbed on Japanese cedar pollen, and airborne particles which contained allergenic particles mainly distributed in < 1 microm size range. The highest mass concentration of chemical elements in Shanghai airborne particles was found in the 0.3-0.18 microm size range, but mass level of pollutant elements, such as S and Pb, in ambient in ultrafine (nano) particles were higher than that in coarse and fine particles. And also, pollen particles were found in Shanghai airborne particles. Synergistic effects between diesel exhaust particles (DEPs), which were the main component in urban airborne particles, and ambient pollens in urban atmosphere can be found, but their mechanism have not been clear. After our new results and other conclusions published recently on allergenic pollen and airborne fine/ultrafine particles were summarized, perspectives of this new discipline were presented.