rna rat , a in China g
Lan Yao a, Fei Yang a, Yaling Lu a, W a Environment Research Institute, Shandong University, Jin b School of Environmental Science and Engineering, Shand c nces, B
Received 24 April 2014 nocturnal variations of PAHs suggested that gas/particle partitioning drivenby temperaturemakes d biological stressors, llergy, asthma, sensory and Spengler, 2003;
Jie et al., 2011; Zhou ver, previous studies of
Atmospheric Research 153 (2015) 276–285
Contents lists available at ScienceDirect
Atmospheric j ourna l homepage: www.e ls1999; Lee and Chang, 2000; Jo and Seo, 2005; Kotzias et al., 2009; Yang et al., 2009; Pegas et al., 2011; Hasheminassab et al., 2014). The results of these studies showed that people are indoor air havemainly been conducted in residential and school buildings (e.g., Blondeau et al., 2005; Fromme et al., 2008;
Polidori et al., 2009; Massey et al., 2012; Krugly et al., 2014;1. Introduction
Over the last twenty years, considerable efforts around the world have been made to clarify the influence of indoor air quality on human health (Gupta et al., 1996; Hayakawa et al., exposed to a multitude of chemical an some of which cause health problems (a irritation, lung cancer, etc.) (Samet
Bernstein et al., 2008; Rios et al., 2009; et al., 2013; Jovanović et al., 2014). Howea significant contribution to the variation in PAH concentrations. The diagnostic ratios revealed that biomass burning had an important contribution to outdoor PAH concentrations in autumn.
The results of a risk assessment of PAH pollution suggested that indoor PAHs present more carcinogenic and mutagenic risks during daytime. Our results indicated that serious indoor air pollution in a business office presents a high health risk for workers. © 2014 Elsevier B.V. All rights reserved.
Diurnal and nocturnal variationsPM2.5
PAHs⁎ Corresponding author at: Environment Research
University, Jinan 250100, China. Tel./fax: +86 531 8836
E-mail address: email@example.com (L. Yang). http://dx.doi.org/10.1016/j.atmosres.2014.08.014 0169-8095/© 2014 Elsevier B.V. All rights reserved.PAHswere all largely from indoor sources,while during nighttime, the 3–4-ring PAHsweremainly generated indoors and the 5–6-ring PAHs predominantly came from the outdoor air. The diurnal/Received in revised form 27 August 2014
Accepted 27 August 2014
Available online 16 September 2014
Keywords:⁎, ChuanpingMeng , Qi Yuan , Chao Yan , Can Dong , Xiao Sui , enxing Wang a,c an 250100, China ong University, Jinan 250100, China eijing 100012, China a b s t r a c t
Indoor/outdoor and diurnal/nocturnal variations in PM2.5 and associated water-soluble ions and polycyclic aromatic hydrocarbons (PAHs) were examined in a business office during the summer and autumn of 2010 in Jinan, China. Both indoor and outdoor PM2.5 levels were higher than the value recommended by theWHO, and outdoor sourceswere found to be themajor contributors to indoor PM2.5. SO42−, NO3− and NH4+ were the dominant water-soluble ions in both indoor and outdoor particles. During daytime, NO3− mainly came from indoor sources, which was related to the temperature difference between the indoor and outdoor air. During daytime, the 15monitoredChinese Research Academy of Environmental Scie a r t i c l e i n f o
Article history:Yanhong Zhu , Lingxiao Yana,b a,b, a a a a aIndoor/outdoor relationships and diu inwater-soluble ion and PAH concent
PM2.5 of a business office area in JinanInstitute, Shandong 6072.l/nocturnal variations ions in the atmospheric heavily polluted city
Research ev ie r .com/ locate /atmosRivas et al., 2014), while, in comparison, few studies have been performed in business offices (Saraga et al., 2010; Sangiorgi et al., 2011, 2013), despite the fact that they are the workplace for most urban office workers. In addition, few studies have 277Y. Zhu et al. / Atmospheric Research 153 (2015) 276–285focused on the diurnal/nocturnal differences in indoor and outdoor pollution levels (Reisen and Arey, 2005; Wang et al., 2007, 2010; Zimmermann et al., 2012; Souza et al., 2014), though the differences in anthropogenic emissions between daytime and nighttime could affect the contributions from various sources of pollution.
PM2.5, which can easily move from the outdoors into the indoors due to its effective penetration ability (Massey et al., 2012; Barraza et al., 2014; Hassanvand et al., 2014), is an important pollutant in indoor environments. Water-soluble ions are a major chemical component of PM2.5 and account for one-third or more of the particulate mass in Chinese urban regions (Saliba et al., 2009; Chithra and Shiva Nagendra, 2013;
Hassanvand et al., 2014). Moreover, the acidity of PM2.5, which depends on the balance between sulphate and nitrate as the acidic compounds and ammonium as a neutralizing species (Seinfeld and Pandis, 2006), has also been associated with negative effects on human health, mainly in terms of lung function. In addition, by acting as surface-active reagents, water-soluble ions can increase the solubility of toxic organic compounds, such as PAHs, and therefore increase their toxicity to humans (Pongpiachan et al., 2013; Krugly et al., 2014; Kamal et al., 2014). PAHs have received increased attention in recent years in indoor air pollution research due to their potential cytotoxicity, mutagenicity and carcinogenicity in humans (WHO, 1998) and their ability to directly or indirectly damage
DNA (Baird et al., 2005; Novotna et al., 2007; Li et al., 2014).
Therefore, the presence of water-soluble ions and PAHs within
PM2.5 strongly increases their potential for adverse health effects.
Shandong Province, which is located in northern China, is
China's third-biggest economic power, and anthropogenic emissions there contributed approximately 10.00% of SO2, 8.46% of NOx, 9.02% of VOC, 9.11% of PM2.5, 7.33% of BC and 6.66% of OC to China's overall emissions in 2006 (National
Bureau of Statistics of China, 2009; Zhang et al., 2009). Jinan, as the capital of Shandong Province, was listed in the group of large cities with the highest pollution concentrations, including