Source, health risk and composition impact of outdoor very fine particles (VFPs) to school indoor environment in Xi'an, Northwestern China

Hongmei Xu; Benjamin Guinot; Junji Cao; Yaqi Li; Xinyi Niu; Kin Fai Ho; Zhenxing Shen; Suixin Liu; Ting Zhang; Yali Lei; Qian Zhang; Jian Sun; Jinjin Gao

doi:10.1016/j.scitotenv.2017.08.101

Source, health risk and composition impact of outdoor very fine particles (VFPs) to school indoor environment in Xi'an, Northwestern China

Sci Total Environ. 2018 Jan 15:612:238-246. doi: 10.1016/j.scitotenv.2017.08.101. Epub 2017 Sep 1.

Authors

Hongmei Xu¹, Benjamin Guinot², Junji Cao³, Yaqi Li⁴, Xinyi Niu⁵, Kin Fai Ho⁶, Zhenxing Shen⁴, Suixin Liu⁷, Ting Zhang⁷, Yali Lei⁴, Qian Zhang⁴, Jian Sun⁴, Jinjin Gao⁴

Affiliations

¹ 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.
² Laboratoire d'Aérologie, Université de Toulouse, CNRS, UPS, France. Electronic address: benjamin.guinot@aero.obs-mip.fr.
³ Key Lab of Aerosol Chemistry & Physics, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, China; Institute of Global Environmental Change, Xi'an Jiaotong University, Xi'an, China. Electronic address: cao@loess.llqg.ac.cn.
⁴ Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an, China.
⁵ Institute of Global Environmental Change, Xi'an Jiaotong University, Xi'an, China; Key Lab of Aerosol Chemistry & Physics, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, China.
⁶ School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China.
⁷ Key Lab of Aerosol Chemistry & Physics, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, China.

PMID: 28850843
DOI: 10.1016/j.scitotenv.2017.08.101

Abstract

Very fine particles (VFPs, PM_0.25) 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%), SO₄^2- (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 SO₄^2- 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.

Keywords: Classroom; Health risk; Indoor and outdoor; Very fine particles (VFPs, PM(0.25)).