Spatial Distribution of Secondary Organic Aerosol Formation Potential

Jun 28, 2018 - *Phone: 86-010-62755852; fax: 86-010-62755852; e-mail: [email protected]. Present address: Room 402, Environmental Building, College of ...
1 downloads 0 Views 1MB Size
Subscriber access provided by UNIVERSITY OF TOLEDO LIBRARIES

Characterization of Natural and Affected Environments

Spatial distribution of secondary organic aerosol formation potential in China derived from speciated anthropogenic volatile organic compound emissions Rongrong Wu, and Shaodong Xie Environ. Sci. Technol., Just Accepted Manuscript • DOI: 10.1021/acs.est.8b01269 • Publication Date (Web): 28 Jun 2018 Downloaded from http://pubs.acs.org on June 30, 2018

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 34

Environmental Science & Technology

1

Spatial distribution of secondary organic aerosol formation

2

potential in China derived from speciated anthropogenic

3

volatile organic compound emissions

4

Rongrong Wu, Shaodong Xie *

5

College of Environmental Sciences and Engineering, State Key Joint Laboratory of

6

Environmental Simulation and Pollution Control, Peking University, Beijing, 100871, China

7

* Corresponding author phone: 86-010-62755852; fax: 86-010-62755852; e-mail:

8

[email protected]

1 ACS Paragon Plus Environment

Environmental Science & Technology

9

TOC/ Abstract Art

10

2 ACS Paragon Plus Environment

Page 2 of 34

Page 3 of 34

Environmental Science & Technology

11

ABSTRACT

12

Fine particulate matter (PM2.5), largely composed of secondary organic aerosol (SOA), is

13

currently one of the most intractable environmental problems in China. As crucial precursors for

14

SOA, understanding the formation propensity of various volatile organic compound (VOC)

15

species and sources is useful for pollution control. In this work, we estimated the SOA formation

16

potential (SOAP) of anthropogenic VOC emissions based on an improved speciated VOC

17

emission inventory, and investigated its distribution in China. According to our estimates,

18

toluene had the largest SOAP, followed by n-dodecane, m/p-xylene, styrene, n-decane, and n-

19

undecane, while passenger cars, chemical fiber manufacturing, asphalt paving, and building

20

coating were the top five SOAP–contributing sources nationwide. The spatial distribution of

21

SOAP in China shows a distinct pattern of high values in the southeast and low values in the

22

northwest. Beijing–Tianjin–Hebei and surroundings, the Yangtze River Delta, Pearl River Delta,

23

and Sichuan–Chongqing District were found to have the highest SOAP, particularly in urban

24

areas. The major SOAP–contributing species and sources differed among these regions, which

25

was attributed to local industrial and energy structures. Our results suggest that to mitigate PM2.5

26

pollution in China, more efficient SOAP–based control measures should be implemented instead

27

of current emissions-based policies, and VOC control strategies should be adapted to local

28

conditions.

3 ACS Paragon Plus Environment

Environmental Science & Technology

29

1. Introduction

30

Particulate pollution, characterized by high mass concentrations of fine particles (PM2.5)

31

accompanied by low visibility, is one of the most intractable environmental problems in China.1–

32

5

33

well as regional and global climate,5–9 the Chinese government has implemented a series of

34

control strategies to mitigate it.10 Due to these stringent control measures, ambient PM2.5

35

concentrations have been significantly reduced in most Chinese cities over the past several years

36

(annual average PM2.5 concentrations in 2016 were reduced by 34.7% compared to 2013

37

level).11-13 However, greater effort is needed to diminish PM2.5 to a non-threatening level (i.e., an

38

annual average of 10 µg m-3, as proposed by the World Health Organization 14). Data from 338

39

monitoring sites in China showed that 75.1% were in non-attainment status in 2016, and the

40

annual average PM2.5 concentration still exceeded the secondary ambient air quality standard

41

limit (35 µg m-3) by about 34%. The highest PM2.5 concentration levels are found in cities such

42

as Beijing–Tianjin–Hebei and surroundings (BTHS), the Yangtze River Delta (YRD), and the

43

Sichuan–Chongqing economic zone (SC), which are the most developed regions in China. In

44

2016, annual average PM2.5 levels in these regions were 71, 46, and 56 µg m-3, respectively.15

Considering the detrimental effects of particulate pollution on air quality and human health, as

45

Secondary organic aerosols (SOAs), which are primarily formed through photooxidation of

46

volatile and semi–volatile organic compounds, comprise a major fraction of the fine particle

47

mass.16-19 Meanwhile, recent studies have noted that the extremely high PM2.5 mass

48

concentrations in China during the pollution episodes were driven largely by SOA formation.1,2

49

As important precursors of SOAs, volatile organic compounds (VOCs) are estimated to

50

contribute about 16–30% or more of PM2.5 by mass through SOA production.2 Therefore, we can

51

conclude that reducing VOC emissions would help mitigate particulate pollution in China.

4 ACS Paragon Plus Environment

Page 4 of 34

Page 5 of 34

Environmental Science & Technology

52

Intermediate VOCs (IVOCs) were also recently recognized as an important source of SOAs,20-23

53

but we did not consider them in this work due to a lack of available IVOC emission inventory.

54

More work measuring emissions of IVOCs is needed to fill this gap.

55

Although approximately 90% of global VOC emissions are from biogenic sources,

56

anthropogenic emissions often dominate those from vegetation in urban areas, where they have a

57

more significant impact on the local ecosystem and climate.24 In China, anthropogenic VOC

58

emissions have been extraordinarily high (29.94 Tg in 2013), and continue to increase year after

59

year.25 At present, VOCs in China are poorly constrained. Although some VOC control measures

60

were recently implemented, they are all emissions-weighted and do not account for the different

61

potentials of various species for SOA formation, and thus may not efficiently mitigate PM2.5

62

pollution in China. Therefore, thorough knowledge of the propensity of different VOC species

63

and sources for SOA formation is urgently needed. However, few previous studies have provided

64

such information, and the detailed characteristics of SOA formation potential (SOAP) in China

65

are yet to be reported.

66

This study is the second in a series of papers intended to develop a high-resolution speciated

67

anthropogenic VOC emission inventory, and then to investigate the effects of VOC emissions on

68

ozone (O3) and SOA formation. Here, we focus on the importance of VOCs to SOA formation.

69

Based on the improved speciated anthropogenic VOC emission inventory developed for the year

70

2013 in our previous study,26 we calculated the inventory-based SOAP using SOA yield method,

71

and identified the major species and sources contributing to SOAP. We also investigated the

72

spatial distribution of SOAP in China, and discuss the characteristics of SOAP in the most

73

heavily polluted regions of China, i.e., BTHS, the YRD, Pearl River Delta (PRD) and SC. Our

74

results provide useful insight for pollution control in China.

5 ACS Paragon Plus Environment

Environmental Science & Technology

Page 6 of 34

75

2. Methods

76

2.1 Speciated VOC emissions in 2013

77

To obtain speciated VOC emissions, we should first determine bulk emissions. Using the bulk

78

emission inventory and an integrated VOC source profile database, speciated VOC emissions

79

were calculated by multiplying bulk emissions by the corresponding profiles, as formulated in Eq.

80

(1). Details on the methodology used to establish the speciated inventory were provided in our

81

previous study.26 Table S1 and Table S2 list the national and provincial speciated VOC

82

emissions in 2013.

83

Etotal, j = ∑i Ei ×fi, j

(1)

84

where Etotal, j and Ei are the total emissions of species j from all source sectors and from source i,

85

respectively, and fi, j is the weight percentage by mass of species j from source i.

86

2.2 Calculation of SOAP

87

The propensity of different VOC compounds to form SOA differs significantly, which can be

88

scaled to the SOA yield. Thus, the SOAP of various species can be calculated using Eq. (2).

89

SOAPi, j =Ei, j ×YSOA, j

(2)

90

where SOAPi,j and Ei,j are the SOAP and emissions of species j from source i, respectively, and

91

YSOA,j is the corresponding SOA yield of species j.

92

In previous studies, the fractional aerosol coefficient (FAC) was generally used to calculate

93

SOAP. FAC is a fixed value that cannot well represent real conditions. In this work, SOA yields

94

were used instead, accounting for important parameters such as organic aerosol concentration,

95

type of oxidant, and NOx concentration in the calculation.

96

There are two parameterization approaches derived from the gas-particle partitioning theory,

97

i.e., the two-product and volatility basis set (VBS) models. The two-product model can simulate 6 ACS Paragon Plus Environment

Page 7 of 34

Environmental Science & Technology

98

most real atmospheric conditions, and has been widely used in previous experimental and

99

modeling studies.27–31 Because of its simplicity, computational efficiency and good performance

100

to a certain extent,32 the two-product approach was chosen to calculate the SOA yield of various

101

VOC species, as formulated in Eq. (3). More information about this method can be found in Wu

102

et al.32

103

YSOA = ∆VOC =M0 1+Mi P,i + 1+M K ∆M

αK

αj KP,j

0 P,i

0 KP,j



(3)

104

where ∆M is the mass of organic aerosol produced (µg m-3), ∆VOC is the amount of VOCs

105

reacted (µg m-3), M0 is the mass concentration of organic aerosol, αi and αj are mass-based

106

stoichiometric yields for semi-volatile species i and j, respectively, and KP,i and KP,j are their gas-

107

particle partitioning coefficients.

108

The values of αi, αj, KP,i and KP,j for various VOC species can be determined by fitting the

109

smog chamber data reported in previous studies to Eq. (3).For species that lack experimental data,

110

FAC values proposed by Grosjean and Seinfeld33 or SOA yields of species with similar

111

structures were used instead.32 The value of M0 was estimated by multiplying the ambient PM2.5

112

mass concentration in different provinces with the corresponding mass fraction of organic

113

components. The annual average PM2.5 mass concentrations in 74 cities in China for the year

114

2013 were collected from the website of the China National Environmental Monitoring Center,34

115

and the average ratio of the organic fraction was determined to be 40% according to local

116

measurements in four megacities in China.2 Notably, this ratio changes among seasons, regions,

117

and pollution conditions.35 Therefore, setting it to a fixed value would certainly introduce

118

uncertainties to the estimates. Further work is needed to improve its estimation. In addition, the

119

NOx concentration can significantly affect SOA yields. VOCs have higher SOA yields under

120

low-NOx conditions.36–40 In this work, we used the emissions ratios of VOCs/NOx to determine 7 ACS Paragon Plus Environment

Environmental Science & Technology

121

NOx concentration levels in Chinese cities, as described by Wu et al.32 Provincial NOx emissions

122

were obtained from Zhao et al.41 The VOCs/NOx ratios varied from 0.5-1.8 in different provinces,

123

considered high-NOx conditions.36,38,39

124

Using this method, the SOA yields of 117 VOC species in China were determined. Table S1

125

shows the nationally averaged SOA yields of different VOC species. It is obvious that aromatics

126

and long-chain alkanes have greater propensity to form SOA than other species, which is

127

consistent with existing knowledge.42-45 A comparison with the results derived from VBS

128

approach is provided in Text S1 and Table S3 in the Supporting Information (SI).

129

2.3 Spatial allocation

130

Gridded SOAP were calculated first by distributing the provincial values to counties using

131

source–specific spatial surrogates (including gross domestic product for transportation and

132

solvent use, secondary industry output for industrial processes, population for stationary fossil

133

fuel combustion, and sown area for biomass burning).25 County–level SOAP was further

134

allocated to grids according to the grid–to–county area ratio and aggregated using Mapinfo.26

135

Finally, the gridded SOAP was mapped at a resolution of 12 km × 12 km using ArcGIS.

136

3. Results and Discussion

137

3.1 SOAP at the national level

138

3.1.1 By species

139

According to our estimates, anthropogenic VOC emissions in China for 2013 had a potential to

140

form 1471.1 Gg SOA. The uncertainty of this estimate is described in Text S2. As shown in

141

Table 1, aromatics had the largest SOAP, with a contribution of 68.6%, followed by alkanes

142

(27.1%). By contrast, the SOAP of alkenes and oxygenated VOCs (OVOCs) were relatively low,

143

accounting for 2.4% and 1.9%, respectively, of the total SOAP.

8 ACS Paragon Plus Environment

Page 8 of 34

Page 9 of 34

144

Environmental Science & Technology

Table 1. SOAP of anthropogenic VOC emissions in China, 2013 Species

SOAP (Gg yr-1)

Percent (%)

Species

SOAP (Gg yr-1)

Percent (%)

Alkanes Alkenes Alkynes Aromatics

398.1 35.6 0.0 1008.5

27.1 2.4 0.0 68.6

Halocarbons OVOCs Others Total

1.0 27.9 0.0 1471.1

0.1 1.9 0.0 100

toluene n-dodecane m/p-xylene styrene n-decane n-undecane ethylbenzene o-xylene 1,3-butadiene methyl cyclohexane n-nonane n-heptane benzene m-ethyltolune n-octane 1,2,4-trimethylbenzene acetone hexanal o-ethyltoluene 3-methylheptane p-diethylbenzene 2,2,4-trimethylpentane 1,2,3-trimethylbenzene 2-methylheptane pentanal m-diethylbenzene

667.7 167.9 102.2 76.7 68.1 67.8 51.5 47.9 33.9 27.1 23.8 15.2 13.1 12.0 8.2 7.8 7.2 7.0 6.7 6.6 6.1 4.5 4.4 4.1 4.0 3.3

45.4 11.4 6.9 5.2 4.6 4.6 3.5 3.3 2.3 1.8 1.6 1.0 0.9 0.8 0.6 0.5 0.5 0.5 0.5 0.4 0.4 0.3 0.3 0.3 0.3 0.2

p-ethyltoluene isopropylbenzene 1,3,5-trimethylbenzene cyclopenane heptanal 2,3,4-trimethylpentane 4-methyl-2-pentanone octanal n-propylbenzene isovaleraldehyde 1-hexene nonanal methyl ethyl ketone decanal chrolobenzene cyclohexane isoprene o-diethylbenzene methylcylopentane methyl vinyl ketone 1,4-dichlorobenzene 1,3-dichlorobenzene 1,2-dichlorobenzene MTBE Others

2.7 2.5 2.4 2.3 2.1 1.7 1.7 1.5 1.3 1.3 1.2 1.1 1.0 0.8 0.6 0.6 0.5 0.3 0.2 0.1 0.1 0.1 0.1 0.1 0.0

0.2 0.2 0.2 0.2 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.04 0.04 0.03 0.02 0.02 0.01 0.01 0.01 0.01 0.01 0.0

145

In terms of individual species, toluene was the largest SOAP contributor (45.4%), which

146

was attributed to its large emissions and high SOA yield. n-Dodecane, m/p-xylene, styrene, n-

147

decane and n-undecane also made significant contributions to SOA formation, accounting for 9 ACS Paragon Plus Environment

Environmental Science & Technology

148

11.4%, 6.9%, 5.2%, 4.6%, and 4.6%, respectively, of total SOAP. Ethylbenzene, o-xylene, 1,3-

149

butadiene, methyl cyclohexane, n-nonane and n-heptane also had relatively high propensity to

150

form SOA, as shown in Table 1. In total, these 12 species contributed 91.8% of total SOAP from

151

28.3% of the national emissions. All of these compounds are aromatics and alkanes except 1,3-

152

butadiene, which indicates that aromatics and long-chain alkanes are the major SOA precursors,

153

in accordance with current knowledge.42–45

154

It should be noted that species with large emissions do not necessarily have high SOAP,

155

which is attributed to their propensity to form SOA, as scaled using the SOA yield in this work.

156

For example, styrene had the largest emissions (7% of the total) but only contributed 5% of the

157

total SOAP due to its low SOA yield (3.9%). By contrast, the emissions of n-dodecane (1.3%),

158

n-decane (1.0%), and n-undecane (0.7) were relatively small, but due to their distinctly high

159

SOA yields, (estimated to be 44%, 22%, and 33%, respectively), they constituted 11.4%, 4.6%,

160

and 4.6% of the total SOAP.

161

3.1.2 By source

162

Industrial processes were the sector that contributed most to SOAP, constituting 40.1% of total

163

SOAP, as shown in Figure 1(a), followed by transportation (23.6%) and solvent use (22.7%).

164

The SOAPs of biomass burning (8.9%) and stationary fossil fuel combustion (4.6%) were

165

relatively small. Among all subsectors, the petrochemical industry and on–road vehicles had the

166

largest SOAP, accounting for 23.7% and 21.1% of the total, respectively. Other industrial

167

processes, surface coating and asphalt paving also made significant contributions to SOA

168

formation. Together, these sources constituted 37% of total SOAP.

169

Figure 1(b) shows the SOAP-based source distribution at a more detailed level. It shows

170

that passenger cars (PCs), chemical fiber manufacturing, coke production, asphalt paving,

10 ACS Paragon Plus Environment

Page 10 of 34

Page 11 of 34

Environmental Science & Technology

171

building coating, household liquefied petroleum gas (LPG) combustion, cement production,

172

motorcycles (MCs), rubber products, and paint and ink manufacturing were 10 classes with the

173

greatest SOAP. They contributed 62.2% of the national SOAP in total. More than 60 remaining

174

sectors constituted only 37.8% of the total SOAP, which indicates that they had little effect on

175

SOA formation. Thus, to mitigate the particulate pollution in China efficiently, these sources of

176

VOC emissions should be preferentially controlled. 8.9%

4.6% 3.2% 2.5% 3.4%

7.1%

7.1%

7.4%

23.6%

4.9%

6.7% 21.1%

14.4% 4.7%

23.7%

4.6% 3.9% 3.5% 2.9% 2.5% 2.5% 2.3% 2.2%

13.4% 40.1%

22.7% 7.1%

16.5%

(a) major and subsectors

177

28.3%

(b) sector branches

Transportation

Biomass burning

Fossil fuel

on-road fossil_power pesticides PCs chemical fiber coking

off-road biomass_open fossil_heat fossil_domestic printing asphalt paving asphalt paving cement building coating MCs LPG_domestic rubbers

Industiral processes biomass_domestic petrochemical surface coating paint and ink plastic biomass_domestic

Solvent use fossil_industry other industries other solvent refinning vehicle coating others

178

Figure 1. Source distribution of SOAP in China, 2013. Sectors with contribution ratios less than

179

2% are not labeled due to limited space.

180

3.2 SOAP in typical regions

181

Figure S1 shows the provincial SOAP and the corresponding source distribution in 2013. Both

182

SOAP and its distribution varied significantly among regions. BTHS (including Beijing, Tianjin,

183

Hebei, Shandong and Henan Province), the YRD (including Shanghai, Jiangsu and Zhejiang

184

Province) and the PRD (referring to Guangdong Province in this study) had much larger SOAP 11 ACS Paragon Plus Environment

Environmental Science & Technology

185

values than other regions. In fact, BTHS, the YRD, the PRD, and the SC suffer from the most

186

severe particulate pollution in China. To obtain useful information for pollution control, further

187

investigation of the characteristics of SOAP in these regions is discussed in the following

188

sections.

189

3.2.1 SOAP in the BTHS

190

In 2013, the BTHS region showed a propensity to form 354.4 Gg of SOA, accounting for 24% of

191

the national SOAP, along with 26% of anthropogenic VOC emissions. As shown in Figure 2,

192

aromatics were always the predominant contributors to SOAP in the four regions, followed by

193

alkanes. These classes constituted 68–72% and 24–28%, respectively, of the regional SOAP.

194

Figure 2 also illustrates the source distributions of SOAP. In the BTHS region,

195

petrochemical industries (24.9%) and on-road vehicles (24.2%) made the largest contributions to

196

SOA formation, followed by other industrial processes, surface coating and asphalt paving. More

197

specifically, passenger cars (18.1%) represented the subsector with the largest SOAP, followed

198

by coke production (8.4%), rubber product manufacturing (8.4%), asphalt paving (7.3%) and

199

building coating (5.5%), as shown in Table S4.

200

Figure 3 shows the top 5 species in terms of SOAP and the corresponding source

201

distributions in various regions. In BTHS, toluene, n-dodecane, m/p-xylene, styrene and n-

202

undecane were the top 5 species, accounting for 43.1%, 11.0%, 7.2%, 5.2%, and 4.7%,

203

respectively, of the total SOAP. Toluene was sourced mainly from on-road vehicles (29.4%), as

204

well as other industrial processes (21.3%), petrochemical industries (19.8%) and surface coating

205

(12.0%). Emissions of n-dodecane was dominated by other industrial processes (46.7%) and

206

asphalt paving (35.9%), followed by on-road vehicles with a contribution of 12.6%. For m/p-

207

xylene, surface coating, petrochemical industries and on-road vehicles were the major

12 ACS Paragon Plus Environment

Page 12 of 34

Page 13 of 34

Environmental Science & Technology

208

contributors to emissions. As a commonly used chemical, nearly 70% of styrene was contributed

209

from petrochemical industries. n-Undecane was mainly emitted from asphalt paving, other

210

industrial processes, petrochemical industries and on–road vehicles.

211

In conclusion, the BTHS region accounted for 24% of the SOAP in China in 2013. Toluene,

212

n-dodecane, m/p-xylene, styrene and n-undecane were the key species contributing to SOAP,

213

while passenger cars, coke production, rubber product manufacturing, asphalt paving and

214

building coating were the major sources. Therefore, to efficiently reduce SOA formation in this

215

region, we suggest listing these species and sources as control priorities.

216

3.2.2 SOAP in the YRD

217

The SOAP in the YRD was estimated to be 331.5 Gg in 2013, contributing 23% of the national

218

SOAP with 18% of VOC emissions .Petrochemical industries (38.6%) were the greatest

219

contributor to SOAP in this region, followed by surface coating (17.0%) and on–road vehicles

220

(13.3%), as shown in Figure 2. In addition, other asphalt paving (8.6%) and industrial processes

221

(6.9%) played important roles in SOA formation. Among all subsectors, chemical fiber

222

manufacturing (22.6%) had the largest SOAP, followed by passenger cars (9.2%), asphalt paving

223

(8.6%), building coating (8.0%) and household LPG combustion (4.1%) (see Table S4).

224

Compared to BTHS, the petrochemical industry and surface coating made greater contributions

225

to SOAP in the YRD, which is attributed to the well-developed organic synthesis industry (e.g.,

226

chemical fiber, paint and ink manufacturing) and associated huge consumption of solvents.

227

Because both the petrochemical industry and surface coating involve the use of numerous

228

aromatic components, aromatics in this region accounted for a higher SOAP contribution

229

proportion than in the BTHS.

13 ACS Paragon Plus Environment

Environmental Science & Technology

230

The top 5 species in terms of SOAP in this region were toluene (47.8%), n-dodecane

231

(9.9%), m/p-xylene (7.3%), styrene (5.6%) and ethylbenzene (4.7%). As illustrated in Figure 3,

232

the source distributions of these species were quite different from those in BTHS except for n-

233

dodecane and styrene. For example, more than half of toluene was from the petrochemical

234

industry in the YRD, while in BTHS industry accounted for only 19.8% of toluene emissions.

235

Although surface coating was also the predominant contributor to m/p-xylene (57.3%) in this

236

region, its contribution proportion was much larger than that in the BTHS (30.6%). These results

237

were largely attributed to the booming organic synthesis industry and extensive solvent use in the

238

YRD.

239

In general, the YRD region contributed 18% of national SOAP in 2013. Toluene, n-

240

dodecane, m/p-xylene, styrene and ethylbenzene were the key species, while chemical fiber

241

manufacturing, passenger cars, asphalt paving, building coating and household LPG combustion

242

were the predominant sources of SOA formation in this region. Our results indicate that it would

243

be more efficient to mitigate particulate pollution in the YRD by reducing the VOC emissions

244

associated with above sources and species.

245

3.2.3 SOAP in the PRD

246

The SOAP in the PRD region was estimated to be 156.8 Gg, constituting 10.7% of the national

247

total, in a region with 9.3% of the total VOC emissions. Surface coating was the largest

248

contributor to SOAP in this region, followed by petrochemical industries and on-road vehicles.

249

These sources constituted 24.2%, 21.1%, and 16.5%, respectively, of the regional SOAP. The

250

SOAP contribution of household fossil fuel combustion, mainly dominated by LPG combustion,

251

was markedly increased in the PRD (11.2%) compared to other regions (less than 5%), probably

252

because LPG is the major residential energy source in this region. According to statistical data,

14 ACS Paragon Plus Environment

Page 14 of 34

Page 15 of 34

Environmental Science & Technology

253

LPG consumption in Guangdong Province is the highest in China, and source apportionment

254

results showed that LPG was one of the major VOC sources in PRD cities.46,47 Among all

255

subsectors, building coating (14.5%) and household LPG combustion (11.2%) were the largest

256

SOAP contributors in this region, followed by motorcycles (7.2%), asphalt paving (6.9%) and

257

passenger cars (6.2%), as shown in Table S4. Notably, surface coating made a much greater

258

contribution to SOA formation in the PRD than in other regions, which is closely tied to the local

259

industrial infrastructure and development. The high content of aromatics in solvents led to the

260

increased contribution from aromatics in this region compared to other areas.

261

In terms of key species, toluene was the greatest SOAP contributor (39.8%), followed by n-

262

dodecane (10.1%), m/p-xylene (9.3%), styrene (9.1%), and n-decane (6.1%). However, in

263

contrast with other regions, toluene in the PRD was sourced mainly from surface coating

264

(30.1%), rather than on-road vehicles (20.3%) or petrochemical industries (20.2%). In addition,

265

household fossil fuel combustion (11.3%) contributed a larger proportion than in other regions.

266

Despite the similarity in the distributions of m/p-xylene and styrene in the PRD and YRD,

267

household fossil fuel combustion made greater contributions to emissions in the PRD. These

268

findings are consistent with the source distribution of SOAP. The emissions of n-dodecane were

269

also dominated by other industrial processes (37.1%) and asphalt paving (37.1%), similar to our

270

results in the other two regions. Household fossil fuel combustion (33.4%) was the largest

271

contributor to n-decane emissions, followed by asphalt paving (14.7%), industrial fossil fuel

272

combustion (14.1%), and printing and dying (9.5%). It is apparent that household fossil fuel

273

combustion, in particular LPG combustion, plays a more important role in SOA formation in the

274

PRD.

15 ACS Paragon Plus Environment

2.7 1.5 1.4 3.1 3.9

Page 16 of 34

x10

Environmental Science & Technology

24.2

27.1

0.1 2.3

24.9 10.7

2.5 1.7

67.5

25.2

50

100

150

200

250

300

350

400

3.8

450

0

0

4.1 2.2

BTHS: 354.4 Gg

18.4

12

7.3

1.9 2.2

x10

6.5

13.3

38.6

Chemical distribution(%) alkanes alkenes alkynes aromatics 1.0 0.0 OVOCs others

50

15.4

1.0 0.0

3.0

17.0

100

18.8 19.2

6.9

SC: 70.3 Gg

150

5.3

3.2 8.6

YRD: 331.5 Gg 2.6

200

1.3

1.4

300

0.1 2.5

24.2

250

28.2

11.2

67.9

4.9 1.6

PRD: 156.8 Gg

1.8

1.8

71.8 26.4

16.5 21.1

Source contribution(%) on-road vehicles off-road transportation biomass open burning biofuel combustion industrial combustion power generation heat supply residential combustion petroleum industry other industrial process pesticide use printing and dying asphalt paving surface coating other solvent use

1.3 5.7

24.2 5.2

275

70.5

6.9

276

Figure 2. Chemical and source distributions of SOAP in four typical regions of China. Sectors with contribution ratios less than 1%

277

are not labeled due to limited space. The graphics of spatial distribution of AOD in this figure was created using ArcGIS software by Esri. ArcGIS®

278

and ArcMap™ are the intellectual property of Esri and are used herein under license.

16 ACS Paragon Plus Environment

Page 17 of 34

Environmental Science & Technology

2.1% 4.1% 3.4% 3.8%

6.8%

4.1%

4.4% 16.5%

29.4%

46.7%

20.4%

12.6%

BTHS

20.0%

8.4%

19.6%

29.6% 19.8%

12.0% 21.3%

26.1%

n-dodecane

3.5%

e n e l y h t e

4.6%

toluene

2.3%

styrene

m/p-xylene

7.3%

2.8%

2.1%

8.5%

17.0%

31.5%

YRD

n-undecane

3.5%

15.2% 14.4%

3.2%

23.0%

69.0%

30.6%

35.9%

42.6%

7.5%

11.0%

8.0%

5.1%

51.7% 15.6%

72.2%

57.3%

46.7%

47.7%

4.7% 3.1%

toluene

n-dodecane

5.2% 2.5%

m/p-xylene

PRD

6.4%

6.2%

15.6% 20.3%

37.1%

13.6%

a

14.1%

28.7%

11.4%

8.5%

11.3%

10.2%

33.4%

30.1%

6.0% 52.8%

37.1%

14.7%

56.9% 3.5% 3.5%

e n e l y h t e

6.1%

n-dodecane

toluene

m/p-xylene

8.9%

3.2%

29.6%

SC

64.2% 16.8%

19.5%

6.9%

6.3%

9.3%

13.3%

19.7%

20.5%

13.6%

10.1% 5.1% 20.9%

18.3%

42.8%

off-road transportation heat supply printing and dying

m/p-xylene

1284 0

biomass open burning residential combustion asphalt paving

3

3

1284 0

n-undecane biofuel combustion petroleum industry surface coating

x10

n-dodecane

x10

3

x10

3

x10

3

x10

279

on-road vehicles power generation pesticide use

1284 0

27.3%

5.6%

37.7%

53.6%

14.0%

toluene

9.5%

n-decane

styrene

2.6% 2.1%

2.6%

1284 0

a

2.1%

20.2%

3.2%

ethylbenzene

4.6% 3.6%

11.3%

styrene

1284 0

o-xylene industrial combustion other industrial process other solvent use

280

Figure 3. Source distribution of top 5 species in terms of SOAP in four regions. Sectors with

281

contribution ratios less than 2% are not labeled due to limited space.

17 ACS Paragon Plus Environment

Environmental Science & Technology

282

In summary, the PRD region made up 10.7% of the national SOAP in 2013. Toluene, n-

283

dodecane, m/p-xylene, styrene and n-decane were the crucial species and building coating,

284

household LPG combustion, motorcycles, asphalt paving, and passenger cars were the crucial

285

sources of SOAP in this region. Hence, to mitigate particulate pollution, VOC emissions controls

286

in the PRD region should be targeted to these key species and sources.

287

3.2.4 SOAP in the SC

288

The SC region was estimated to have a potential to form 70.3 Gg of SOA, responsible for 4.8%

289

of total SOAP in China, with 5% of national VOC emissions. As shown in Figure 2, on–road

290

vehicles (25.2%) had the largest SOAP in this region, followed by other industrial processes

291

(19.2%), surface coating (18.8%), and petrochemical industries (15.4%). Interestingly, household

292

biomass combustion made a much larger contribution to SOAP (6.5%) in the SC region than in

293

other three regions (1.0–2.7%). Among all subsectors, passenger cars were the largest SOAP

294

contributor (with a contribution of 17.6%). In addition, building coating (9.4%), cement

295

production (8.0%), coke production (5.5%), vehicle manufacturing (5.4%), asphalt paving

296

(5.3%), motorcycles (4.4%), and household crop residue combustion (4.2%) also made important

297

contributions to SOA formation in this region, as shown in Table S4. .We found that the key

298

sources of SOAP in SC differed somewhat from those in other regions, with the most obvious

299

discrepancy being that other industrial processes (mainly cement production and coke production)

300

and household biomass combustion made larger contributions to SOA formation, which is

301

related to the local industries and energy sources.

302

Toluene was also the largest SOAP contributor in the SC region, followed by n-dodecane,

303

m/p-xylene, n-undecane and o-xylene. They constituted 44.6%, 13.6%, 7.6%, 4.9%, and 3.9% of

304

the total SOAP. As depicted in Figure 3, the source distributions of toluene, n-dodecane, and

18 ACS Paragon Plus Environment

Page 18 of 34

Page 19 of 34

Environmental Science & Technology

305

m/p-xylene in this region were similar to those in other regions, with the exception of higher

306

contribution from other industrial processes. About 38% of n-undecane emissions were from

307

other industrial processes, followed by on-road vehicles (19.7%) and asphalt paving (18.3%).

308

Surface coating was the predominant source of o-xylene, contributing 42.8% of its emissions.

309

In general, the SC region constituted 4.8% of SOAP in China in 2013. Toluene, n-dodecane,

310

m/p-xylene, n-undecane and o-xylene, and passenger cars were the key species to SOAP, and

311

building coating, cement production, coke production and vehicle manufacturing were the main

312

sources. Based on these results, we believe that it would be more efficient to mitigate particulate

313

pollution in the SC region by reducing the emissions of these key species and sources.

314

3.3 Spatial distribution of SOAP

315

3.3.1 At the national level

316

The spatial distribution of SOAP at a resolution of 12 km × 12 km is illustrated in Figure 4(a),

317

which shows that southeastern China had much higher SOAP than northwestern area. The

318

coastal regions had the greatest SOAP intensity (~139 kg km-2 or more). By contrast, except for

319

some parts of Xinjiang and Gansu, the SOAP intensity in west China was generally lower than

320

6.9 kg km-2. The BTHS, YRD, PRD, SC, as well as the Wuhan and Changzhou–Zhuzhou–

321

Xiangtan metropolitan zones, had higher SOAP than other regions of China. There regions are

322

more likely to suffer from severe particulate pollution due to their high propensity to form SOA,

323

which is consistent with the high PM2.5 concentrations in these areas, as shown in Figure 4(b).

324

3.3.2 At the regional level

325

To better understand the spatial distributions of SOAP in the four typical regions, we conducted

326

in-depth analyses, described in this section.

19 ACS Paragon Plus Environment

Environmental Science & Technology

327

(1) The BTHS region. As shown in Figure 4(A), the gridded SOAP values of cities in the

328

BTHS region were greater than 50 Mg, except for Chengde, Zhangjiakou, Baoding, Sanmenxia,

329

Zhumadian, Xinyang, Luoyang, and Nanyang. In south Beijing, south Tianjin, central Hebei,

330

north Henan, and most parts of Shandong Province, the gridded SOAPs were greater than 100

331

Mg, particularly in urban areas, such as Beijing, Tianjin, Shijiazhuang, Jinan, and Zibo. The

332

gridded SOAP values in these cities exceeded 200 Mg, which was largely attributed to high local

333

VOC emissions intensities. The grid with the largest SOAP was found in Qingdao City, which

334

reached 5.33 Gg.

335

(2) The YRD region. The gridded SOAP values of most cities in this region were greater

336

than 50 Mg, as shown in Figure 4(B). The central area had higher SOAP than other parts of the

337

YRD, particularly in Shanghai, Nanjing, Yangzhou, Zhenjiang, Changzhou, Suzhou, Wuxi,

338

Jiaxing, Huzhou, Hangzhou, Ningbo, Shaoxing, Taizhou and Wenzhou, where the gridded

339

SOAP exceeded 200 Mg. The most developed district, Pudong New Area, contributed more than

340

50% of Shanghai’s anthropogenic VOC emissions, with the highest gridded SOAP (7.92 Gg) in

341

the YRD region.

342

(3) The PRD region. As shown in Figure 4(C), the gridded SOAP values in most cities in

343

this region were less than 100 Mg except in the central region, including mainly Guangzhou,

344

Foshan, Dongguan, Shenzhen and Zhongshan. These cities had the highest propensity to form

345

SOA in the PRD. Their gridded SOAP exceeded 200 Mg. Jieyang, Shantou and south Maoming

346

also had high SOAP, with gridded values in the range of 100-200 Mg. In addition, some high

347

points were observed in the urban areas of Huizhou, Maoming, Zhaoqing, and Shaoguan City.

348

Within this region, the largest gridded SOAP value was found in urban Guangzhou, reaching

349

3.65 Gg.

20 ACS Paragon Plus Environment

Page 20 of 34

Page 21 of 34

Environmental Science & Technology

350

(4) The SC region. It is evident that the SOAP of SC district was about half to one order of

351

magnitude smaller than those of the other three regions, which can be attributed to the less

352

developed economy of this region (thus less VOC emissions). As shown in Figure 4(D), the

353

gridded SOAPs of the western Sichuan Basin, including Ngawa, Garze, Liangshan and

354

Panzhihua, were less than 5 Mg. By contrast, SOAP increased to 20 Mg grid-1 or more in the

355

eastern part of the basin. This is because the western SC region is a mountainous and relatively

356

undeveloped area, while the eastern part, including two metropolises of Chengdu and

357

Chongqing, is the political and economic center of this region, with a dense population and high

358

rate of vehicle ownership. Consequently, Chengdu and Chongqing had the largest SOAP in this

359

region, particularly among urban areas (with gridded SOAP exceeding 100 Mg). In addition,

360

high points were found in Deyang, Mianyang, Zigong, Changshou County and Fuling.

361

According to our estimates, the largest gridded SOAP value was found in urban Chengdu, at 712

362

Mg.

363

In conclusion, urban areas had greater SOAP than other parts, and thus a higher risk for

364

particulate pollution. Therefore, it is more critical to implement pollution control measures in the

365

urban areas.

21 ACS Paragon Plus Environment

Environmental Science & Technology

366

22 ACS Paragon Plus Environment

Page 22 of 34

Page 23 of 34

Environmental Science & Technology

367

Figure 4. Spatial distributions of (a) SOAP and (b) satellite–derived PM2.5 mass concentrations

368

(dust and sea-salt removed) in China, 2013. The satellite–derived PM2.5 data were provided by

369

van Donkelaar et al. on the website at http://fizz.phys.dal.ca/~atmos/martin/?page_id=140. The

370

graphics in each section were created using ArcGIS software by Esri. ArcGIS® and ArcMap™

371

are the intellectual property of Esri and are used herein under license.

372

3.4 Implications for SOAP-based VOC control strategies in China

373

Table S5 lists the top 20 VOC species in terms of emissions and SOAP. The order of species in

374

terms of SOAP differed significantly from that of emissions, which is attributable to differences

375

in SOA yield among species. Therefore, VOC control strategies based on SOAP differ

376

significantly from those based on emissions. From the perspective of emissions, styrene, toluene,

377

m/p-xylene, benzene, ethylene and the other 15 high–emissions species should be targeted. If

378

emissions of these compounds were reduced to zero without any offset, it would lead to a VOC

379

emissions reduction of 60.4% and a SOAP reduction of 65.7%. The efficiency of an emissions-

380

based strategy for SOAP reduction is 0.053 g SOAP/g. From the perspective of SOAP, toluene,

381

n-dodecane, m/p-xylene, styrene, n-decane and other 15 major SOAP contributors should be

382

controlled preferentially. If releases of these compounds were reduced to zero without any offset,

383

it would reduce total SOAP by 96.3% with a VOC emissions reduction of 39.7%. Thus, when

384

implementing SOAP-based control measurements, a 1g VOC reduction would lead to a 0.12g

385

SOAP reduction. Note that this comparison was made under the assumption that emissions

386

would be reduced completely. Accounting for many other factors, such as technological

387

feasibility and economic costs, reducing emissions of any VOC compounds will not necessarily

388

lead to a proportional reduction of SOAP. It is nonetheless obvious that SOAP-based control

389

strategies are more efficient than emissions-based policies in terms of reducing SOA formation. 23 ACS Paragon Plus Environment

Environmental Science & Technology

Page 24 of 34

390

Considering its efficiency in mitigating secondary particulate pollution, we suggest that

391

SOAP-based VOC control strategies should be implemented instead of the current emissions-

392

based regulatory policies. Due to the different industrial and energy structures among regions in

393

China, control targets also differ, as noted above. Table 2 summarizes the VOC species and

394

sources that should be controlled preferentially at the national and regional levels based on our

395

results. Some control measures that play a role in mitigating particulate pollution may be

396

ineffective at reducing O3 pollution.48,49 Therefore, we conducted a comparison of control

397

suggestions for O3 and SOA formation, and propose O3/PM2.5 synergistic control strategies based

398

on our results (see Text S3, Table S6, and Figure S2). In addition, SOAP varies seasonally due to

399

temporal variation in anthropogenic VOC emissions, as shown in Figure S3 and Figure S4.

400

However, the discrepancies among seasons were very small because of little monthly variation in

401

emissions from industrial processes, transportation and solvent use, which were the major

402

contributors to SOAP (see Text S4 for details).

403

Table 2. Suggested VOC emission control targets in different regions of China No.

Nationwide

BTHS

YRD

PRD

SC

Species 1

toluene

toluene

toluene

toluene

toluene

2

n-dodecane

n-dodecane

n-dodecane

n-dodecane

n-dodecane

3

m/p-xylene

m/p-xylene

m/p-xylene

m/p-xylene

m/p-xylene

4

styrene

styrene

styrene

Styrene

n-undecane

5

n-decane

n-undecane

ethylbenzene

n-decane

o-xylene

Source sectors 1

passenger cars

passenger cars

chemical fiber manufacturing

building coating

passenger cars

2

chemical fiber manufacturing

coke production

passenger cars

household LPG combustion

building coating

24 ACS Paragon Plus Environment

Page 25 of 34

Environmental Science & Technology

3

coke production

rubber product manufacturing

asphalt paving

motorcycles

cement production

4

asphalt paving

asphalt paving

building coating

asphalt paving

coke production

5

building coating

building coating

household LPG combustion

passenger cars

vehicle manufacturing

404

Lastly, we note that SOAP is used in this work to quantify the importance of different VOC

405

species and sources to SOA formation. It cannot be used as a metric for measuring actual SOA

406

production under real atmospheric conditions. We used SOAP here to identify the major VOC

407

contributors to SOA formation in China, which might provide useful insights for particulate

408

pollution control in China.

25 ACS Paragon Plus Environment

Environmental Science & Technology

409

Supporting Information

410

The Supporting Information is available free of charge on the ACS Publications website.

411

Additional information on VBS approach and its comparison with two-product model,

412

uncertainty analysis, comparison of SOAP– and OFP–based control strategies, and temporal

413

characteristics of SOAP; Tables showing speciated VOC emissions at the national and province

414

level, comparison of SOA yields calculated by two-product and VBS models, source

415

distributions of SOAP in four typical regions, top 20 species in terms of emissions and SOAP,

416

and top 20 species in terms of SOAP and OFP; Figures showing SOAP and the corresponding

417

source distribution in different provinces of China, source distributions in terms of SOAP and

418

OFP, monthly variation profiles and Monthly SOAP in China.

419

Author Information

420

Corresponding Authors: Shaodong Xie

421

Phone: 86-010-62755852; fax: 86-010-62755852; e-mail: [email protected]

422

Present Address: Room 402, Environmental Building, College of Environmental Sciences and

423

Engineering, State Key Joint Laboratory of Environmental Simulation and Pollution Control,

424

Peking University, No.5 Yiheyuan Road, Haidian District, Beijing, 100871, China

425

Notes: The authors declare no competing financial interest.

426

Acknowledgements

427

This work received funding from the National Natural Science Foundation as part of the key

428

project entitled “The development and validation of emission inventories of anthropogenic

429

volatile organic compounds in the Beijing–Tianjin–Hebei region, China” (No. 91544106), and

430

from the National Air Pollution Prevention Joint Research Center as part of the Premier Fund 26 ACS Paragon Plus Environment

Page 26 of 34

Page 27 of 34

Environmental Science & Technology

431

Project named “The research of characteristics, emission reduction and regulatory system of

432

volatile organic compounds (VOCs) in key sectors” (No. DQGG0204).

27 ACS Paragon Plus Environment

Environmental Science & Technology

433

References

434

(1) Guo, S.; Hu, M.; Zamora, M. L.; Peng, J.; Shang, D.; Zheng, J.; Du, Z.; Wu, Z.; Shao, M.;

435

Zeng, L., Elucidating severe urban haze formation in China. Proc. Natl. Acad. Sci. 2014, 111,

436

(49), 17373-17378.

437

(2) Huang, R. J.; Zhang, Y.; Bozzetti, C.; Ho, K. F.; Cao, J. J.; Han, Y.; Daellenbach, K. R.;

438

Slowik, J. G.; Platt, S. M.; Canonaco, F.; Zotter, P.; Wolf, R.; Pieber, S. M.; Bruns, E. A.; Crippa,

439

M.; Ciarelli, G.; Piazzalunga, A.; Schwikowski, M.; Abbaszade, G.; Schnelle-Kreis, J.;

440

Zimmermann, R.; An, Z.; Szidat, S.; Baltensperger, U.; El Haddad, I.; Prevot, A. S., High

441

secondary aerosol contribution to particulate pollution during haze events in China. Nature 2014,

442

514, (7521), 218-22.

443

(3) Wang, Y.; Liu, Z.; Zhang, J.; Hu, B.; Ji, D.; Yu, Y.; Wang, Y., Aerosol physicochemical

444

properties and implications for visibility during an intense haze episode during winter in Beijing.

445

Atmos. Chem. Phys. 2015, 15, (6), 3205-3215.

446

(4) Yang, Y.; Liu, X.; Qu, Y.; An, J.; Jiang, R.; Zhang, Y.; Sun, Y.; Wu, Z.; Zhang, F.; Xu, W.,

447

Characteristics and formation mechanism of continuous hazes in China: a case study during the

448

autumn of 2014 in the North China Plain. Atmos. Chem. Phys. 2015, 15, (14), 8165.

449

(5) Zhang, X.; Wang, Y.; Niu, T.; Zhang, X.; Gong, S.; Zhang, Y.; Sun, J., Atmospheric aerosol

450

compositions in China: spatial/temporal variability, chemical signature, regional haze

451

distribution and comparisons with global aerosols. Atmos. Chem. Phys. 2012, 12, (2), 779-799.

452

(6) Chen, C.; Liu, C.; Chen, R.; Wang, W.; Li, W.; Kan, H.; Fu, C., Ambient air pollution and

453

daily hospital admissions for mental disorders in Shanghai, China. Sci. Total Environ. 2018, 613,

454

324-330.

455

(7) Guo, P.; Feng, W.; Zheng, M.; Lv, J.; Wang, L.; Liu, J.; Zhang, Y.; Luo, G.; Zhang, Y.; Deng,

28 ACS Paragon Plus Environment

Page 28 of 34

Page 29 of 34

Environmental Science & Technology

456

C., Short-term associations of ambient air pollution and cause-specific emergency department

457

visits in Guangzhou, China. Sci. Total Environ. 2018, 613, 306-313.

458

(8) Liu, H.; Tian, Y.; Cao, Y.; Song, J.; Huang, C.; Xiang, X.; Li, M.; Hu, Y., Fine particulate air

459

pollution and hospital admissions and readmissions for acute myocardial infarction in 26 Chinese

460

cities. Chemosphere 2018, 192, 282-288.

461

(9) Wang, Y.; Zhang, R.; Saravanan, R., Asian pollution climatically modulates mid-latitude

462

cyclones following hierarchical modelling and observational analysis. Nat. Commun. 2014, 5,

463

3098.

464

(10) Air Pollution Prevention And Control Action Plan; China’s State Council (translated by

465

Clean Air Alliance of Chian): Beijing, 2013; http://www.cleanairchina.org/product/6349.html

466

(accessed on 26 June 2016).

467

(11) Monthly/Quarterly Report of Air Quality of 74 Cites; China National Environmental

468

Monitoring Centre: Beijing, 2017. http://www.cnemc.cn/kqzlzkbgyb2092938.jhtml (accessed on

469

26 December 2017).

470

(12) Feng, L.; Ye, B.; Feng, H.; Ren, F.; Huang, S.; Zhang, X.; Zhang, Y.; Du, Q.; Ma, L.,

471

Spatiotemporal Changes in Fine Particulate Matter Pollution and the Associated Mortality

472

Burden in China between 2015 and 2016. Int. J. Environ. Res. Public Health 2017, 14, (11),

473

1321.

474

(13) Zheng, Y.; Xue, T.; Zhang, Q.; Geng, G.; Tong, D.; Li, X.; He, K., Air quality improvements

475

and health benefits from China’s clean air action since 2013. Environ. Res. Lett. 2017, 12, (11),

476

114020.

477

(14) WHO Air quality guidelines for particulate matter, ozone, nitrogen dioxide and sulfur

478

dioxide (Global update 2005)-Summary of risk assessment; World Health Organization:

29 ACS Paragon Plus Environment

Environmental Science & Technology

Page 30 of 34

479

Switzerland,

2006;

480

http://apps.who.int/iris/bitstream/10665/69477/1/WHO_SDE_PHE_OEH_06.02_eng.pdf

481

(accessed on 01 November 2017).

482

(15) China Environmental State Bulletin 2016; Ministry of Environmental Protection of the

483

People’s

484

http://www.mep.gov.cn/hjzl/zghjzkgb/lnzghjzkgb/201706/P020170605833655914077.pdf

485

(accessed on 20 October 2017)

486

(16) Crounse, J. D.; Nielsen, L. B.; Jørgensen, S.; Kjaergaard, H. G.; Wennberg, P. O.,

487

Autoxidation of Organic Compounds in the Atmosphere. J. Phys. Chem. Lett. 2013, 4, (20),

488

3513-3520.

489

(17) De Gouw, J.; Jimenez, J. L., Organic aerosols in the Earth’s atmosphere. Environ. Sci.

490

Technol. 2009, 43 (20), 7614–7618.

491

(18) Zhang, Q.; Jimenez, J. L.; Canagaratna, M. R.; Allan, J. D.; Coe, H.; Ulbrich, I.; Alfarra, M.

492

R.; Takami, A.; Middlebrook, A. M.; Sun, Y. L.; Dzepina, K.; Dunlea, E.; Docherty, K.; DeCarlo,

493

P. F.; Salcedo, D.; Onasch, T.; Jayne, J. T.; Miyoshi, T.; Shimono, A.; Hatakeyama, S.; Takegawa,

494

N.; Kondo, Y.; Schneider, J.; Drewnick, F.; Borrmann, S.; Weimer, S.; Demerjian, K.; Williams,

495

P.; Bower, K.; Bahreini, R.; Cottrell, L.; Griffin, R. J.; Rautiainen, J.; Sun, J. Y.; Zhang, Y. M.;

496

Worsnop, D. R., Ubiquity and dominance of oxygenated species in organic aerosols in

497

anthropogenically-influenced Northern Hemisphere midlatitudes. Geophys. Res. Lett. 2007, 34,

498

(13), L13801.

499

(19) Ziemann, P. J.; Atkinson, R., Kinetics, products, and mechanisms of secondary organic

500

aerosol formation. Chem. Soc. Rev. 2012, 41, (19), 6582-605.

Republic

of

China:

30 ACS Paragon Plus Environment

Beijing,

2017;

Page 31 of 34

Environmental Science & Technology

501

(20) Zhao, Y.; Hennigan, C. J.; May, A. A.; Tkacik, D. S.; de Gouw, J. A.; Gilman, J. B.; Kuster,

502

W. C.; Borbon, A.; Robinson, A. L., Intermediate-volatility organic compounds: a large source

503

of secondary organic aerosol. Environ. Sci. Technol. 2014, 48, (23), 13743-13750.

504

(21) Zhao, Y.; Nguyen, N. T.; Presto, A. A.; Hennigan, C. J.; May, A. A.; Robinson, A. L.,

505

Intermediate volatility organic compound emissions from on-road gasoline vehicles and small

506

off-road gasoline engines. Environ. Sci. Technol. 2016, 50, (8), 4554-4563.

507

(22) Gentner, D. R.; Isaacman, G.; Worton, D. R.; Chan, A. W.; Dallmann, T. R.; Davis, L.; Liu,

508

S.; Day, D. A.; Russell, L. M.; Wilson, K. R., Elucidating secondary organic aerosol from diesel

509

and gasoline vehicles through detailed characterization of organic carbon emissions. Proc. Natl.

510

Acad. Sci. 2012, 109, (45), 18318-18323.

511

(23) Zhao, Y.; Saleh, R.; Saliba, G.; Presto, A. A.; Gordon, T. D.; Drozd, G. T.; Goldstein, A. H.;

512

Donahue, N. M.; Robinson, A. L., Reducing secondary organic aerosol formation from gasoline

513

vehicle exhaust. Proc. Natl. Acad. Sci. 2017, 114, (27), 6984-6989.

514

(24) Atkinson, R.; Arey, J., Atmospheric degradation of volatile organic compounds. Chem. Rev.

515

2003, 103, (12), 4605-4638.

516

(25) Wu, R.; Bo, Y.; Li, J.; Li, L.; Li, Y.; Xie, S., Method to establish the emission inventory of

517

anthropogenic volatile organic compounds in China and its application in the period 2008–2012.

518

Atmos. Environ. 2016, 127, 244-254.

519

(26) Wu, R.; Xie, S., Spatial Distribution of Ozone Formation in China Derived from Emissions

520

of Speciated Volatile Organic Compounds. Environ. Sci. Technol. 2017, 51, (5), 2574-2583.

521

(27) Ceulemans, K.; Compernolle, S.; Müller, J. F., Parameterising secondary organic aerosol

522

from α-pinene using a detailed oxidation and aerosol formation model. Atmos. Chem. Phys.

523

2012, 12, (12), 5343-5366.

31 ACS Paragon Plus Environment

Environmental Science & Technology

524

(28) Chan, A. W. H.; Kautzman, K. E.; Chhabra, P. S.; Surratt, J. D.; Chan, M. N.; Crounse, J. D.;

525

Kürten, A.; Wennberg, P. O.; Flagan, R. C.; Seinfeld, J. H., Secondary organic aerosol formation

526

from photooxidation of naphthalene and alkylnaphthalenes: implications for oxidation of

527

intermediate volatility organic compounds (IVOCs). Atmos. Chem. Phys. 2009, 9, (9), 3049-

528

3060.

529

(29) Hallquist, M.; Wenger, J.; Baltensperger, U.; Rudich, Y.; Simpson, D.; Claeys, M.;

530

Dommen, J.; Donahue, N.; George, C.; Goldstein, A., The formation, properties and impact of

531

secondary organic aerosol: current and emerging issues. Atmos. Chem. Phys. 2009, 9, (14), 5155-

532

5236.

533

(30) Kanakidou, M.; Seinfeld, J.; Pandis, S.; Barnes, I.; Dentener, F.; Facchini, M.; Dingenen, R.

534

V.; Ervens, B.; Nenes, A.; Nielsen, C., Organic aerosol and global climate modelling: a review.

535

Atmos. Chem. Phys. 2005, 5, (4), 1053-1123.

536

(31) Seinfeld, J. H.; Pankow, J. F., Organic atmospheric particulate material. Annu. Rev. Phys.

537

Chem. 2003, 54, (1), 121-140.

538

(32) Wu, W.; Zhao, B.; Wang, S.; Hao, J., Ozone and secondary organic aerosol formation

539

potential from anthropogenic volatile organic compounds emissions in China. J. Environ. Sci.

540

2017, 53, 224-237.

541

(33) Grosjean, D.; Seinfeld, J. H., Parameterization of the formation potential of secondary

542

organic aerosols. Atmos. Environ. (1967) 1989, 23, (8), 1733-1747.

543

(34) National Air Quality Historical Data; China National Environmental Monitoring Center:

544

Beijing. http://beijingair.sinaapp.com/ (accessed on 26 July 2017).

545

(35) Zheng, J.; Hu, M.; Peng, J.; Wu, Z.; Kumar, P.; Li, M.; Wang, Y.; Guo, S., Spatial

546

distributions and chemical properties of PM2. 5 based on 21 field campaigns at 17 sites in China.

32 ACS Paragon Plus Environment

Page 32 of 34

Page 33 of 34

Environmental Science & Technology

547

Chemosphere 2016, 159, 480-487.

548

(36) Lane, T. E.; Donahue, N. M.; Pandis, S. N., Effect of NOx on secondary organic aerosol

549

concentrations. Environ. Sci. Technol. 2008, 42, (16), 6022-6027.

550

(37) Ng, N.; Chhabra, P.; Chan, A.; Surratt, J. D.; Kroll, J.; Kwan, A.; McCabe, D.; Wennberg, P.;

551

Sorooshian, A.; Murphy, S., Effect of NOx level on secondary organic aerosol (SOA) formation

552

from the photooxidation of terpenes. Atmos. Chem. Phys. 2007, 7, (19), 5159-5174.

553

(38) Sarrafzadeh, M.; Wildt, J.; Pullinen, I.; Springer, M.; Kleist, E.; Tillmann, R.; Schmitt, S.

554

H.; Wu, C.; Mentel, T. F.; Zhao, D., Impact of NO x and OH on secondary organic aerosol

555

formation from β-pinene photooxidation. Atmos. Chem. Phys. 2016, 16, (17), 11237-11248.

556

(39) Song, C.; Na, K.; Cocker, D. R., Impact of the hydrocarbon to NO x ratio on secondary

557

organic aerosol formation. Environ. Sci. Technol. 2005, 39, (9), 3143-3149.

558

(40) Zhao, D.; Schmitt, S. H.; Wang, M.; Acir, I.-H.; Tillmann, R.; Tan, Z.; Novelli, A.; Fuchs,

559

H.; Pullinen, I.; Wegener, R., Effects of NO x and SO 2 on the secondary organic aerosol

560

formation from photooxidation of α-pinene and limonene. Atmos. Chem. Phys. 2018, 18, (3),

561

1611-1628.

562

(41) Zhao, B.; Wang, S.; Liu, H.; Xu, J.; Fu, K.; Klimont, Z.; Hao, J.; He, K.; Cofala, J.; Amann,

563

M., NO x emissions in China: historical trends and future perspectives. Atmos. Chem. Phys.

564

2013, 13, (19), 9869-9897.

565

(42) Aumont, B.; Valorso, R.; Mouchel-Vallon, C.; Camredon, M.; Lee-Taylor, J.; Madronich, S.,

566

Modeling SOA formation from the oxidation of intermediate volatility n-alkanes. Atmos. Chem.

567

Phys. 2012, 12, (16), 7577-7589.

568

(43) Ng, N.; Kroll, J.; Chan, A.; Chhabra, P.; Flagan, R.; Seinfeld, J., Secondary organic aerosol

569

formation from m-xylene, toluene, and benzene. Atmos. Chem. Phys. 2007, 7, (14), 3909-3922.

33 ACS Paragon Plus Environment

Environmental Science & Technology

570

(44) Presto, A. A.; Miracolo, M. A.; Donahue, N. M.; Robinson, A. L., Secondary organic aerosol

571

formation from high-NOx photo-oxidation of low volatility precursors: n-alkanes. Environ. Sci.

572

Technol. 2010, 44, (6), 2029-2034.

573

(45) Tkacik, D. S.; Presto, A. A.; Donahue, N. M.; Robinson, A. L., Secondary organic aerosol

574

formation from intermediate-volatility organic compounds: cyclic, linear, and branched alkanes.

575

Environ. Sci. Technol.2012, 46, (16), 8773-81.

576

(46) Liu, Y.; Shao, M.; Lu, S.; Chang, C.-C.; Wang, J.-L.; Fu, L., Source apportionment of

577

ambient volatile organic compounds in the Pearl River Delta, China: Part II. Atmos. Environ.

578

2008, 42, (25), 6261-6274.

579

(47) Wang, J.-L.; Wang, C.-H.; Lai, C.-H.; Chang, C.-C.; Liu, Y.; Zhang, Y.; Liu, S.; Shao, M.,

580

Characterization of ozone precursors in the Pearl River Delta by time series observation of non-

581

methane hydrocarbons. Atmos. Environ. 2008, 42, (25), 6233-6246.

582

(48) Li, N.; He, Q.; Greenberg, J.; Guenther, A.; Li, J.; Cao, J.; Wang, J.; Liao, H.; Wang, Q.;

583

Zhang, Q., Impacts of biogenic and anthropogenic emissions on summertime ozone formation in

584

the Guanzhong Basin, China. Atmos. Chem. Phys. 2018, 18, (10), 7489-7507.

585

(49) Su, W.; Liu, C.; Hu, Q.; Fan, G.; Xie, Z.; Huang, X.; Zhang, T.; Chen, Z.; Dong, Y.; Ji, X.,

586

Characterization of ozone in the lower troposphere during the 2016 G20 conference in

587

Hangzhou. Sci. Rep. 2017, 7, (1), 17368.

34 ACS Paragon Plus Environment

Page 34 of 34