Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an, China; Key Lab of Aerosol Chemistry & Physics, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, China; Laboratoire d'Aérologie, Université de Toulouse, CNRS, UPS, France.
Laboratoire d'Aérologie, Université de Toulouse, CNRS, UPS, France.
Sci Total Environ. 2018 Jan 15;612:238-246. doi: 10.1016/j.scitotenv.2017.08.101. Epub 2017 Sep 1.
Very fine particles (VFPs, PM) are able to travel deeply into the respiratory tract and can produce adverse health effects, especially to children. Information on the VFPs in schools is generally lacking. We investigated the chemical compositions, sources and health risks of VFPs in a junior secondary school of Xi'an, China, during May 16th to 30th, 2012. The results showed that organic matter (37% and 39%), SO (13% and 11%) and geological material (20% and 24%) were the major components of VFPs both outdoors and indoors. The VFP species indoors, such as SO and elemental carbon, are mainly from outdoor origins, e.g. coal burning and traffic emissions. But particle resuspension by student activities, chalk dust and import from outdoors of soil dust also contributed to deteriorate air quality in the classroom. By contrast to outdoors, several indoor factors, like higher room temperature, limited volume and longer suspension time of classroom particles, can even lead to significant secondary pollutant production. Heavy metals (mainly from outside) bound to indoor VFPs are supposedly associated to non-cancer health risks, especially Pb through ingestion pathway and Mn through dermal contact. Outdoor VFPs may be associated to PAHs cancer health risks via inhalation way. This study confirms that both indoor and outdoor sources had contributions to indoor VFPs, and that VFPs health risk should be of higher concern in urban areas of Northwestern China.
非常细颗粒物（VFPs，PM）能够深入到呼吸道并产生不良健康影响，尤其是对儿童。关于学校内 VFPs 的信息通常是缺乏的。我们调查了中国西安市一所初中 2012 年 5 月 16 日至 30 日期间室内外 VFPs 的化学成分、来源和健康风险。结果表明，有机物（37%和39%）、SO（13%和11%）和地质材料（20%和24%）是室内外 VFPs 的主要成分。室内 VFP 物种，如 SO 和元素碳，主要来自室外来源，如燃煤和交通排放。但学生活动、粉笔灰尘和室外土壤灰尘的再悬浮也导致了教室空气质量的恶化。与室外相比，几个室内因素，如较高的室温、有限的教室颗粒体积和较长的悬浮时间，甚至可以导致二次污染物的显著产生。结合到室内 VFPs 的重金属（主要来自室外）可能与非癌症健康风险有关，特别是通过摄入途径的 Pb 和通过皮肤接触的 Mn。室外 VFPs 可能通过吸入途径与多环芳烃的癌症健康风险有关。这项研究证实，室内和室外来源都对室内 VFPs 有贡献，在中国西北地区的城市地区，应更加关注 VFPs 的健康风险。
