Using a Vegetative Environmental Buffer to Reduce the

Jun 29, 2018 - Sampling campaigns were conducted at two farms, one with and one without a VEB. Of the nine compounds measured, methanol, ethanol, and ...
0 downloads 0 Views 765KB Size
Subscriber access provided by UNIVERSITY OF TOLEDO LIBRARIES

Agricultural and Environmental Chemistry

Using a Vegetative Environmental Buffer to Reduce the Concentrations of Volatile Organic Compounds in Poultry House Atmospheric Emissions Qi Yao, Alba Torrents, Hong Li, Michael Buser, Laura L. Mcconnell, Peter M Downey, and Cathleen Joan Hapeman J. Agric. Food Chem., Just Accepted Manuscript • DOI: 10.1021/acs.jafc.8b00088 • Publication Date (Web): 29 Jun 2018 Downloaded from http://pubs.acs.org on June 29, 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 28

Journal of Agricultural and Food Chemistry

1

Using a Vegetative Environmental Buffer to Reduce the Concentrations of Volatile Organic

2

Compounds in Poultry House Atmospheric Emissions

3 4

Qi Yao1, Alba Torrents1, Hong Li2, Michael D. Buser3, Laura L. McConnell1, Peter M. Downey4,

5

Cathleen J. Hapeman4,*

6 7

1

8

Martin Hall, College Park, Maryland, 20742, USA

9

2

Department of Civil and Environmental Engineering, University of Maryland,1173 Glenn L.

Department of Animal and Food Sciences, University of Delaware, 046 Townsend Hall,

10

Newark, DE 19716, USA

11

3

12

Hall, Stillwater, OK 74078, USA

13

4

14

Avenue, Beltsville, MD 20705, USA

Biosystems and Agricultural Engineering Department, Oklahoma State University, 223 Ag

US Department of Agriculture, Agricultural Research Service (USDA-ARS), 10300 Baltimore

15 16

*

Corresponding author: Tel: 301-504-6451, e-mail address: [email protected]

17 18

DISCLAIMER

19

Mention of trade names or commercial products in this publication is solely for the purpose of

20

providing specific information and does not imply recommendation or endorsement by

21

University of Maryland, Oklahoma State University, University of Delaware, or United States

22

Department of Agriculture (USDA). University of Maryland, Oklahoma State University,

23

University of Delaware, and USDA are equal opportunity providers and employers.

1 ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

Page 2 of 28

24

KEYWORDS

25

volatile organic compound (VOC), VOC emission, poultry production, vegetative environmental

26

buffer (VEB), ozone formation potential (OFP)

27 28 29

ABSTRACT Ground-level ozone is formed when volatile organic compounds (VOCs) react with

30

hydroxyl radicals and nitrogen oxides in the presence of ultraviolet light. Research has typically

31

focused on the release and control of VOCs from hydrocarbon processing, however, agricultural

32

activities, such as poultry production, can also be VOC sources and potentially contribute to

33

ozone pollution. Therefore, this study examines the emission of C2 - C6 VOCs emitted from

34

poultry houses and the use of a vegetative environmental buffer (VEB) as a potential mitigation

35

strategy. Sampling campaigns were conducted at two farms, one with and one without a VEB. Of

36

the nine compounds measured, methanol, ethanol, and acetone were the primary VOCs emitted

37

and had the largest ozone formation potential (OFP). A significantly larger decrease in the OFP

38

for methanol was observed as a function of distance from the poultry house at the farm with the

39

VEB as compared to the farm without the VEB. These results suggest that besides a visual

40

barrier and particulate screen, VEBs can provide some control of VOCs emitted from poul try

41

production.

2 ACS Paragon Plus Environment

Page 3 of 28

42

Journal of Agricultural and Food Chemistry

INTRODUCTION

43 44

Ozone is one of the six criteria air pollutants identified in the Clean Air Act by the United

45

States Environmental Protection Agency (US EPA) and is a major component in photochemical

46

smog. Ground-level ozone is a concern because it can cause severe respiratory problems among

47

older adults and young children and can negatively affect vegetation including agricultural crops

48

and seed production1-5. Ozone concentrations can reach unhealthful levels when the temperature

49

is high and few or no clouds are present with little or no wind. Typically in the US, average

50

ozone concentration levels are the highest during April to October. In 2015, the US EPA

51

strengthened the National Ambient Air Quality Standards (NAAQS) for ground-level ozone. The

52

current NAAQS for ground-level ozone is an eight-hour average concentration of 70 ppb (0.14

53

µg/m3 at 25 °C)6.

54

Ground-level ozone is formed in the atmosphere when volatile organic compounds

55

(VOCs) react with hydroxyl radicals and nitrogen oxides in the presence of ultraviolet light.

56

However, some VOCs react quickly with hydroxyl radicals (e.g., xylenes) and are referred to as

57

reactive organic gases, while other VOCs (e.g., methane) are virtually non-reactive with

58

hydroxyl radicals. Short chain alcohols are moderately reactive7,8. Therefore, decreasing the

59

amount of VOCs released to the atmosphere can lead to reducing ozone formation.

60

Ground-level ozone concentrations in the Chesapeake Bay region have become a

61

concern. Over 30 counties in this area did not meet the new US EPA ground-level ozone

62

requirement during 2012 to 2014, and those areas are likely to be designated as nonattainment

63

areas9. In addition, high levels of NOx primarily due to massive electric power plants and large

64

traffic volumes are released to the atmosphere in this region1. With the increasing encroachment

3 ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

65

of urbanization into agricultural lands, the ozone formation potential of the VOCs released from

66

agriculture needs to be considered. Previous experiments have shown that the ozone formation

67

potential (OFP) of VOCs emitted from poultry waste was more than twice the OFP associated

68

with VOC emissions from swine, beef cattle, or dairy cattle farms10.

69

Page 4 of 28

The Chesapeake Bay region and Delmarva Peninsula have become one of the major

70

poultry-producing areas because of the large markets from New York to Washington, DC11, 12.

71

Nearly 600 million broilers were produced on the Delmarva Peninsula in 201711. This rapid

72

expansion and consolidation of industrialized poultry operations has raised concerns about the air

73

pollutants emitted from these facilities and the negative impacts that these pollutants can have on

74

the public health and the surrounding environment. Generally, odorous compounds emitted by

75

concentrated animal feeding operations (CAFOs) can be a social problem and can negatively

76

affect rural and state economies13. Inside the poultry house, the most abundant VOCs observed

77

were acetic acid, 2,3-butanedione, methanol, acetone, and ethanol, and the largest concentrations

78

were around ventilation areas14. Furthermore, the primary VOC sources in poultry production

79

were identified as manure, waste bedding, fertilizer and crop residues, and feathers15. Although

80

studies have been conducted measuring and identifying the VOCs inside poultry houses, little

81

VOC emission data are available for outside the poultry houses.

82

Vegetative environmental buffers (VEB) have been introduced to poultry producers as a

83

cost-efficient practice for air pollutant remediation. VEBs are rows of grasses, shrubs, and trees

84

purposefully planted surrounding the CAFOs, which also can provide a more appealing visual

85

for the facilities. Although previous studies have reported that VEBs can reduce VOCs in swine

86

farms16,17, no specific research has been carried related to poultry houses. Vegetation is also a

4 ACS Paragon Plus Environment

Page 5 of 28

Journal of Agricultural and Food Chemistry

87

known VOC source. For example, Miscanthus x giganteus is known to release isoprene18,19,

88

however this compound was not observed inside poultry houses in previous work14.

89

The objectives of this study are to develop VOC specific concentration profiles which

90

began near the sidewall ventilation fans and extended perpendicularly outward from the poultry

91

houses, to examine the ability of VEBs to decrease the concentration of the emitted VOCs, and

92

to evaluate the ozone formation potential (OFP) from the poultry-emitted VOCs. Time-integrated

93

air samples were collected at multiple locations and heights outside of two poultry facilities, one

94

with a VEB and one without, in two air sampling campaigns between very late spring to summer.

95

This time period has higher temperatures relative to fall and winter, which leads to increased

96

poultry house ventilation and presumably to higher levels of VOC emissions. Air samples were

97

analyzed and quantified for nine non-methane VOCs (C2 - C6 molecular weight range): propene,

98

methanol, ethanol, acetone, acetonitrile, propanol, hexane, butanol, and butanal. These VOCs

99

were previously reported with relatively large concentrations inside the poultry houses,

100

especially during warmer and active feeding periods14, and readily react with hydroxyl radicals7.

101 102

MATERIALS AND METHODS

103 104

Site descriptions. Two commercial poultry farms were chosen for the field air sampling

105

campaigns (Fig. 1, Fig. S1). Farm 1 was located in southeastern Pennsylvania and consisted of

106

two poultry houses (152 m length * 15 m width) with approximately 25,000 boilers per house.

107

This facility is a certified organic commercial poultry farm that uses organic-approved feed and

108

litter amendments. The farm produces free-range chickens by providing them with fenced-in

109

outdoor access. Each flock was raised for 50 days with a 10-day down time in between flocks

5 ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

Page 6 of 28

110

when the litter was removed and new bedding was placed in the house. The house included five

111

1.2-m tunnel fans on both sides of the houses at one end of each house. Four 0.9-m sidewall fans

112

(35 m apart) were located on the south sidewall, but were not used during any experiments. A

113

vegetative environmental buffer (VEB) was located parallel to the first house. This VEB

114

consisted of a row of switch-grass (Panicum virgatum) and miscanthus (Giant Miscanthus

115

Miscanthus x giganteus and Miscanthus x giganteus), which were planted in 2012, and a row of

116

Austree hybrid willow trees (Salix matsudana x alba), which was planted in 2007. The species

117

chosen were consistant with recommendations for this area20 The height of the grasses and the

118

willow trees were approximatedly 3 m and 10 m, respectively. The distance between the grass

119

portion of the VEB and the tunnel fans was approximately 5 m.

120

Farm 2 was located in Delaware and consisted of two poultry houses (122 m length * 21

121

m width) with approximately 28,000 boilers per house. This facility is a typical CAFO poultry

122

farm, where each flock was raised on used litter for 60 days with a 10-day inactive time between

123

flocks. Mechanical ventilation of the poultry house was accomplished by five 1.2-m tunnel fans

124

on both sides of the houses at one end of each house. As with Farm 1, the sidewall fans were not

125

used in during any experiments.

126

Air sampling. Two air sampling campaigns were carried out, one at Farm 1 in August

127

2015 and one at Farm 2 in late May 2015. Five daytime and five nighttime field experiments

128

were conducted at each farm, and 13 and 12 2-hr-composite air samples were collected at Farm 1

129

and Farm 2, respectively. At Farm 1, three 10-m sampling towers with multiple sampling heights

130

were deployed perpendicularly to the tunnel fans of house one at distances of 2, 6, and 20 m. The

131

sampling heights above ground level for Tower 1 (T1) were 1, 2, 4.5, 7.25, and 10 m; Tower 2

132

(T2) were 1, 2, 4.5, and 7.25 m; and Tower 3 (T3) were 2, 4.5, 7.25, and 10 m (Fig. 1). There

6 ACS Paragon Plus Environment

Page 7 of 28

Journal of Agricultural and Food Chemistry

133

was a ground-level elevation drop of about 1 m between T1 and T2 and a drop of about 3 m

134

between T1 and T3. A background sampler was deployed at approximately 150 m away

135

northwest of the tunnel fans. At Farm 2, three 10-m sampling towers with multiple sampling

136

heights were deployed perpendicularly to the tunnel fans of house one at distances of 2, 23, and

137

47 m. The sampling heights above ground level for all towers (T1, T2, and T3) were 2, 4.5, 7.25,

138

and 10 m (Fig. 1). There was no elevation change between T1 and T3. A background sampler

139

was deployed at approximately 70 m away east of the tunnel fans.

140

US EPA Method TO-15 was modified to collect VOCs using 1-L amber glass canisters

141

(Bottle-Vac) coupled with a filtered restrictor to afford 2-hr integrated air samples (Entech

142

Instruments, Inc., Simi Valley, California)21. The filter of the restrictor ensured that particulates

143

were not collected. All canisters were cleaned and evacuated for 20 cycles and reached a final

144

evacuation of -1.04 atm using an Entech 3100A canister cleaner automatic system (Entech

145

Instruments, Inc., Simi Valley, California). During each experiment, one replicate air sample was

146

collected to evaluate the precision of the VOC measurement procedure.

147

Samples were transported to the laboratory and were analyzed within two weeks after

148

collection. Meteorological conditions (temperature, pressure, relative humidity, wind speed, and

149

wind direction) were recorded by HOBO U30 Station 3.0.0 (Onset Computer Corporation,

150

Bourne, Massachusetts) (Table SI 1 and S2).

151

Sample analyses. Air samples were analyzed for nine C2 – C6 VOCs (molar mass < 90 g

152

mol-1): propene, methanol, acetone, ethanol, acetonitrile, hexane, propanol, butanol, and butanal.

153

Carbon sulfide, methyl sulfide dimethyl disulfide, dimethyl sulfide, hexanal, toluene, and

154

nonanal were also observed, but the concentrations were not quantified. For these compounds,

7 ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

155

the spectra of each peak were identified using the NIST05 Mass Spectral Library, and the peak

156

areas were used to construct the emission profile figures.

Page 8 of 28

157

A 3400A auto sampler and 7200A pre-concentrator (Entech Instruments, Inc., Simi

158

Valley, California) were used to prepare the gas samples prior to injection into an Agilent 6980N

159

gas chromatograph equipped with a 5973 mass spectrometer (Agilent Technologies, Inc.). The

160

pre-concentrator used three gas concentrating stages to trap water and CO2 prior to the injection

161

onto a GC column (Rxi-1ms, 60m * 0.32mm * 0.1µm Restek Corporation, Bellefonte,

162

Pennsylvania). Instrument settings were as follows: 35 °C hold 5 min, ramp 5 °C /min to 140 °C,

163

ramp 25 °C /min to 220 °C, and hold 5 min; inlet temperature was 175°C, and flow (He) was 1.5

164

mL/min, splitless. The mass spectrometer was operated under both scan and sim modes with

165

electron ionization mode. Calibration gas standards (10 ppm) with a mixture of 8 standard gases

166

were custom made (Restek Corporation, Bellefonte, Pennsylvania). Dilution of calibration gases

167

was performed by a dynamic dilution system 4600A (Entech Instruments, Inc., Simi Valley,

168

California). The detection limit of each VOC was as follow: butanal (6 µg/m3), butanol (6

169

µg/m3), hexane (7 µg/m3), propanol (5 µg/m3), acetone (5 µg/m3), acetonitrile (3 µg/m3), ethanol

170

(4 µg/m3), methanol (3 µg/m3), and propene (3 µg/m3). The replicate precision values for the

171

most abundant VOCs (methanol, ethanol, and acetone) met or exceeded the US EPA TO-15

172

method21.

173

Gradient figures and statistical analyses. Plume figures were constructed using

174

pollutant concentrations and plotted as a function of distance and/or height from the tunnel fans.

175

Figures were created in MATLAB R2016a using the griddata function (The Math Works, Inc.,

176

Natick, MA) to interpolate concentration data linearly. All statistical analyses (student t-test,

8 ACS Paragon Plus Environment

Page 9 of 28

Journal of Agricultural and Food Chemistry

177

standard variance) were performed using GraphPad Prism, Version 5.01 (GraphPad Software,

178

Inc., La Jolla, CA) and Microsoft Excel 2016 (office.microsoft.com).

179

Relative VOC concentrations were used in the data analysis, because the range of

180

concentrations was very large between experiments. Relative concentrations (  .)

181

were obtained by normalizing all VOC concentrations to the concentrations observed at the 2-m

182

height of Tower 1 in the same experiment; these samples are referred to as the reference sample.

183

Normalization allowed for comparison of the two campaigns. For VOC concentrations below the

184

limit of detection, 0.5 of the value of the limit of detection was used for statistical analyses and

185

figure construction. VOC levels from background samples varied significantly and were likely

186

influenced by additional sources. These values were not used to correct the sample

187

concentrations observed at T1, T2, and T3.

.

188 189 190

RESULTS AND DISCUSSION Composite air samples were collected at multiple heights and distances on three sampling

191

towers during five daytime and five nighttime field experiments at both poultry farms (Fig. 1.).

192

Samples were analyzed for nine C2 – C6 VOCs (molar mass < 90 g mol-1): propene, methanol,

193

acetone, ethanol, acetonitrile, hexane, propanol, butanol, and butanal.

194

During the ten sampling time periods at Farm 1, the daytime and nighttime (mean ±

195

standard deviation) temperatures were 27.2 ± 1.5 °C and 22.0 ± 2.1 °C; atmospheric pressures

196

were 0.89 ± 0.01 atm and 0.94 ± 0.01 atm; relative humidity was 49% ± 4% and 67% ± 3%, calm

197

percentages (wind speed < 0.5 m s-1) were 52% ± 30% and 100% ± 0%, respectively. (SI, Table

198

S1). At Farm 2, daytime and nighttime (mean ± standard deviation) temperatures were 20.2 ± 4.4

199

°C and 22.2 ± 3.0 °C; atmospheric pressures were 0.97 ± 0.02 atm and 0.92 ± 0.03 atm; relative 9 ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

Page 10 of 28

200

humidity was 73% ± 17% and 76% ± 13%, calm percentages (wind speed < 0.5 m s-1) were 25%

201

± 30% and 46% ± 38% during sampling time, respectively (SI, Table S2). The higher

202

temperatures during the campaign at Farm 1 compared to temperatures during the campaign

203

conducted at Farm 2 presumably contributed to the larger VOC concentrations observed, even

204

though the total ventilation rates were significantly higher at Farm 2 (SI, Tables S3, S4, t-test, p

205

< 0.05).

206

Methanol concentrations and sources. Of the VOCs measured in this study, the most

207

abundant VOC observed at both farms was methanol, and all samples contained detectable levels

208

of methanol. The methanol concentrations at the same sampling points for each experiment at

209

both farms were significantly larger than all the other measured VOCs (t-test, p < 0.05). For

210

Farm 1 at the 2-m height, the average methanol concentrations (ranges) were 182 µg m-3 (128 -

211

226 µg m-3) at T1 and 47 µg m-3 (12 - 110 µg m-3) at T3 during the day, and 207 µg m-3 (174 -

212

254 µg m-3) and 76 µg m-3 (48 - 112 µg m-3) for nighttime. The distance between T1 and T3 at

213

Farm 1 was 18 m, and the correspondingly-similar distance at Farm 2 was between T1 and T2

214

(21 m). At Farm 2 (2-m height), the average methanol concentrations were 116 µg m-3 (96 - 138

215

µg m-3) and 56 µg m-3 (17 - 127 µg m-3) at T1 and T2 during the day, respectively, and were 106

216

µg m-3 (69 - 137 µg m-3) and 83 µg m-3 (37 - 124 µg m-3) for nighttime. The difference in

217

average methanol concentrations between the two poultry houses may be due to the different

218

house managements and temperatures.

219

To compare the VOC emissions between experiments, relative concentration was used

220

due to the wide range of concentration levels. Relative concentrations were plotted as a function

221

of distance to the primary ventilation fan and the height for each experiment at both farms (Fig.

222

2; SI Figs. S3, S4). A representative relative methanol concentration gradient during daytime at

10 ACS Paragon Plus Environment

Page 11 of 28

Journal of Agricultural and Food Chemistry

223

Farm 1 shows the emission plume originating from the ventilation fan (Fig. 2a). In some

224

experiments, the plume lofted upwards in the relative short distance from T1 to T2 (< 5 m), most

225

likely due to the presence of the VEB (Fig. 2a; SI, Fig. S3). This is consistent with previous

226

studies22,23. Fig. 2c shows an extended plume of more than 40 m observed at Farm 2. Thus, the

227

VEB prevented the VOC plume from moving far beyond the poultry house.

228

A typical methanol emission pattern during the nighttime at Farm 1 is shown in Fig. 2b.

229

It is somewhat similar to the emission plume that emanated from the ventilation fan during the

230

day, however, the plume height was much lower and reached further into the VEB. This is not

231

unexpected as much calmer wind conditions and lower temperatures during the nighttime can

232

create a nocturnal radiation inversion. The ground-level methanol plumes were trapped under the

233

warmer air giving rise to the suppressed and extended plume shape. Similar to Fig. 2b, the

234

nighttime plume of Farm 2 shown in Fig. 2d is suppressed and somewhat extended.

235

For each campaign at ground-level (2-m height), the day and nighttime relative methanol

236

concentration reductions were not significantly different (t-test, p > 0.1). The relative methanol

237

concentrations at Farm 1 decreased by 69% ± 13% over the span of 18 m (T1 to T3) for all ten

238

experiments, whereas, at Farm 2, the decrease in the relative methanol concentrations from T1 to

239

T2 (38% ± 36% over 21 m) for all ten experiments were significantly lower (t-test, p < 0.05).

240

The reduction of methanol concentrations at Farm 2 represents the effect of dispersion as a

241

function of distance only, whereas the methanol concentration decrease at Farm 1 is the result of

242

both dispersion due to distance and interaction the VEB. Furthermore, the relative concentrations

243

at the highest points were not significantly different between both farms (t-test, p > 0.1). Thus,

244

the VEB did not simply push the plume to higher levels above the ground. Although we have no

245

direct evidence, i.e., analyses of plant material, we can surmise that the VEB trapped the VOCs.

11 ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

246

Page 12 of 28

Ethanol and acetone concentrations and sources. The emission patterns of ethanol and

247

acetone were very similar at both farms. The relative ethanol concentrations were plotted as a

248

function of distance from the primary ventilation fan and height for each experiment (Fig. 3, SI

249

Figs. S5 - S8). Results showed that ethanol was emitted from the poultry house (Fig. 3a). The

250

relative concentration gradients for acetone and for ethanol were not significantly different (t-

251

test, p > 0.05). Again, the nocturnal ethanol emission plumes at both farms (Figs. 3b, 3d) was

252

suppressed which is consistent with the inversion pattern observed with methanol. However,

253

high background acetone and ethanol levels observed in some of experiments at both farms

254

suggested that additional sources were present. Dairy and swine facilities have also been reported

255

as significant contributors for both ethanol and acetone emissions24,25, and these types of

256

facilities are within visual distance at both farms.

257

Other VOCs. Acetonitrile, propanol, butanol, hexane, and propene were detected in 40%

258

of the samples collected at Farm 1 (4 experiments), but in less than 5% of the samples from Farm

259

2; thus, the following discussion is for Farm 1 only. For these five VOCs, the ground-level (2-m

260

height) VOC concentrations in front of the ventilation fan were significantly lower (t-test, p
0.1),

288

therefore, all the experiments were used for the following calculations.

289

The ozone formation potential (OFP) of a VOC is a function of its concentration and its

290

maximum incremental reactivity (MIR). MIR, which is used by California Air Resources Board

291

for regulation applications of VOCs associated with ground-level ozone formation, assumes a

13 ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

Page 14 of 28

292

modeled scenario in which the NOx level yields the highest incremental reactivity of the mixture

293

of reactive organic gases. The MIR coefficient is in units of grams O3 per gram VOC27-29 (Eqn.

294

2).

295 296

OFP (j) = Conc (j) × MIR coefficient (j)

(Equation 2)

Table 1 shows the VOC reactivity (Prop-Equiv) of methanol, ethanol, and acetone as

297

well as their respective ozone formation potential (OFP) values and MIR coefficients using the

298

daytime ground-level (2-m height) VOC concentrations from both farms. The largest potential

299

contributor to ozone formation is methanol followed by ethanol and acetone. Direct comparison

300

of the Prop-Equiv and OFP values between the two farms is not appropriate, since data were

301

collected under different environmental conditions, and Prop-Equiv and OFP values are

302

calculated using actual not relative concentrations. However, comparison of the changes in the

303

Prop-Equiv and the OFP values is valid. The changes in the Prop-Equiv and the OFP values for

304

methanol at each farm as a function of distance (2 m and 20 m) are significantly different (t-test,

305

p < 0.05). For methanol, the OFP values decreased 69% ± 13% at Farm 1 and 34% ± 39% at

306

Farm 2. These calculations suggest that using VEBs will reduce VOC concentrations, and

307

furthermore, if VOCs are the limiting factor in ozone formation in this region, VEBs will reduce

308

the potential for ozone formation. Finally, the increases in OFP for ethanol and acetone as a

309

function of increasing distance from the source at Farm 1 again indicate that additional sources

310

for these compounds exist.

311 312

ABBREVIATIONS USED

313 314

ARS – Agricultural Research Service

14 ACS Paragon Plus Environment

Page 15 of 28

Journal of Agricultural and Food Chemistry

315

CAFO – concentrated animal feeding operations

316

Conc – concentration

317

GC – gas chromatography

318

MIR – maximum incremental reactivity

319

NAAQS – National Ambient Air Quality Standards

320

NRCS – Natural Resources Conservation Service

321

OFP – ozone formation potential

322

Prop-Equiv – propene equivalent

323

T1, T2, T3 – Tower 1, Tower 2, Tower 3, respectively

324

USDA – United States Department of Agriculture

325

US EPA – United States Environmental Protection Agency

326

VEB – vegetative environmental buffer

327

VOC – volatile organic compound

15 ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

Page 16 of 28

328

ACKNOWLEDGEMENTS

329

The authors wish to acknowledge the dedicated contributions from numerous field and technical

330

staff, students, growers, and volunteers. Funding for this project was provided by USDA-NRCS

331

Conservation Innovation Grant Program (Award 69-3A75-12-244), University of Delaware,

332

University of Maryland, Oklahoma State University, Pennsylvania State University, and USDA-

333

ARS. This work was also supported financially by USDA-ARS intramural projects in National

334

Program 212, Soil and Air.

335 336

SUPPORTING INFORMATION DESCRIPTION

337 338

Supporting information includes: aerial views of Farm 1 and Farm 2 noting deployment positions

339

of samplers, the meteorological conditions (temperature, relative humidity, pressure, wind speed,

340

and wind direction), tunnel fan data, and the relative concentration profiles of all VOCs

341

measured in all experiments.

342

16 ACS Paragon Plus Environment

Page 17 of 28

Journal of Agricultural and Food Chemistry

343

REFERENCES

344

1. US EPA. (2017). Air Pollution in the Chesapeake Bay Watershed. Retrieved January 2, 2018

345

from https://www.epa.gov/chesapeake-bay-tmdl/air-pollution-chesapeake-bay-watershed

346

2. Iriti, M.; Maro, A. D.; Bernasconi, S.; Burlini, N.; Simonetti, P.; Picchi, V.; Panigada, C.;

347

Gerosa, G.; Parente, A.; Franco Faoro F.; Nutritional Traits of Bean (Phaseolus vulgaris)

348

Seeds from Plants Chronically Exposed to Ozone Pollution. J. Agric. Food Chem. 2009, 57,

349

201–208.

350 351 352 353 354

3. Grunwald, C.; Endress, A. G. Fatty acids of soybean seeds harvested from plants exposed to air pollutants. J. Agric. Food Chem. 1984, 32, 50–53. 4. Meredith, F. I.; Thomas, C. A.; Heggestad, H. E. Effect of the pollutant ozone in ambient air on lima beans. J. Agric. Food Chem. 1986, 34, 179–185. 5. Keutgen, N.; Keutgen, A. J.; Janssens, M. J. J. Sweet Potato [Ipomoea batatas (L.) Lam.]

355

cultivated as tuber or leafy vegetable supplier as affected by elevated tropospheric ozone. J.

356

Agric. Food Chem. 2008, 56, 6686–6690.

357

6. US EPA. (2017). 2015 National Ambient Air Quality Standards (NAAQS) for Ozone.

358

Retrieved April 9, 2018 from https://www.epa.gov/ozone-pollution/2015-national-ambient-

359

air-quality-standards-naaqs-ozone#rule-summary

360

7. Atkinson, R. Kinetics and Mechanisms of the Gas-Phase Reactions of the Hydroxyl Radical

361

with Organic Compounds. American Chemical Society: Washington, DC. 1989. 246 pp.

362 363 364 365

8. Carter, W. Development of ozone reactivity scales for volatile organic compounds. J. Air Waste Manage. Assoc. 1994, 44, 881–899. 9. US EPA. (2015). 2015 Ozone Standards. Retrieved April 9, 2018 from https://ozoneairqualitystandards.epa.gov/OAR_OAQPS/OzoneSliderApp/index.html#

17 ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

366

10. Howard, C. J.; Kumar, A.; Mitloehner, F.; Stackhouse, K.; Green, P. G.; Flocchini, R. G.;

367

Kleeman, M. J. Direct measurements of the ozone formation potential from livestock and

368

poultry waste emissions. Environ. Sci. Technol. 2010, 44, 2292–2298.

369

11. USDA National Agricultural Statistics Service. (2017). United States Department of

370

Agriculture National Agricultural Statistics Service Poultry – Production and Value, 3.

371

Retrieved January 2, 2018 from

372

https://www.nass.usda.gov/Publications/Todays_Reports/reports/plva0418.pdf

373

Page 18 of 28

12. Pew Environment Group. (2011). Big Chicken: Pollution and Industrial Poultry Production

374

in America. January 2, 2018 from

375

http://www.pewtrusts.org/~/media/legacy/uploadedfiles/peg/publications/report/pegbigchicke

376

njuly2011pdf.pdf

377

13. National Research Council, (2003). National Research Council Air Emission from Animal

378

Feeding Operations Current Knowledge Future Needs. Retrieved April 8th, 2018 from

379

https://www3.epa.gov/ttnchie1/ap42/ch09/related/nrcanimalfeed_dec2002.pdf

380 381

14. Trabue, S.; Scoggin, K.; Li, H.; Burns, R.; Xin, H.; Hatfield, J. Speciation of volatile organic compounds from poultry production. Atmos. Environ. 2010, 44, 3538–3546.

382

15. Lacey, R. E., Mukhtar, S., Carey, J. B., and Ullman, J. L. A review of literature concerning

383

odors, ammonia, and dust from broiler production facilities: 1. Odor concentrations and

384

emissions. J. Appl. Poult. Res. 2004, 13:500–508.

385 386

16. Tyndall, J.; Colletti, J. Mitigating swine odor with strategically designed shelterbelt systems: A review. Agrofor. Sys. 2007, 69 (1), 45–65.

18 ACS Paragon Plus Environment

Page 19 of 28

387

Journal of Agricultural and Food Chemistry

17. Parker, D. B.; Malone, G. W.; Walter, W. D. Vegetative environmental buffers and exhaust

388

fan deflectors for reducing downwind odor and VOCs from tunnel-ventilated swine barns.

389

Trans. ASABE 2012, 55, 227–240.

390

18. Copeland, N.; Cape, J. N.; Heal, M. R. Volatile organic compound emissions from

391

Miscanthus and short rotation coppice willow bioenergy crops. Atmos. Environ. 2012, 60,

392

327–335.

393

19. Lamb, B.; Grosjean, D.; Pun, B.; Seigneur, C. (1999). Review of the emissions, atmospheric

394

chemistry, and gas/particle partition of biogenic volatile organic compounds and reaction

395

products. Retrieved January 2, 2018 from https://crcao.org/reports/recentstudies00-02/A-

396

23%20AER%20final%20report.pdf

397

20. Belt. S. V.. Plants tolerant of poultry farm emissions in the Chesapeake Bay watershed. Final

398

study report. Retrieved April 9, 2018 from

399

https://www.nrcs.usda.gov/Internet/FSE_PLANTMATERIALS/publications/mdpmcsr12671.

400

pdf

401

21. US EPA. (2016). EPA Air Method, Toxic Organics - 15 (TO-15). Retrieved April 8, 2018

402

from https://www.epa.gov/homeland-security-research/epa-air-method-toxic-organics-15-15-

403

determination-volatile-organic

404

22. Willis, W. B.; Eichinger, W. E.; Prueger, J. H.; Hapeman, C. J.; Li, H.; Buser, M. D.;

405

Hatfield, J. L.; Wanjura, J. D.; Holt, G. A., Torrents, A.; Plenner, S. J.; Clarida, W, Brown, S.

406

D.; Downey, P. M.; Yao, Q. Lidar method to estimate emission rates from extended sources.

407

J. Atmos. Oceanic Tech. 2017, 34, 335–345.

408 409

23. Willis, W. B.; Eichinger, W. E.; Prueger, J. H.; Hapeman, C. J.; Li, H.; Buser, M. D.; Hatfield, J. L.; Wanjura, J. D.; Holt, G. A., Torrents, A.; Plenner, S. J.; Clarida, W, Brown, S.

19 ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

Page 20 of 28

410

D.; Downey, P. M.; Yao, Q. Particulate capture efficiency of a vegetative environmental

411

buffer surrounding an animal feeding operation. Agric. Ecosys. Environ. 2017, 240, 101–108.

412

24. Filipy, J.; Rumburg, B.; Mount, G.; Westberg, H.; Lamb, B. Identification and quantification

413

of volatile organic compounds from a dairy. Atmos. Environ. 2006, 40, 1480–1494.

414

25. Ni, J. Q.; Robarge, W. P.; Xiao, C.; Heber, A. J. Volatile organic compounds at swine

415 416

facilities: A critical review. Chemosphere 2012, 89, 769–788. 26. Chameides, W. L.; Fehsenfeld, F.; Rodgers, M. O.; Cardelino, C.; Martinez, J. Parrish, D.;

417

Lonneman, W.; Lawson, D. R.; Rasmussen, R. A.; Zimmerman, P.; Greenberg, J.;

418

Middleton, P.; Wang, T. Ozone precursor relationships in the ambient atmosphere. J.

419

Geophy. Res. 1992, 97 (D5), 6037 – 6055.

420

27. California Air Resources Board. (2010). Final statement of reasons for rulemaking: public

421

hearing to consider proposed amendments to the tables of maximum incremental reactivity

422

(MIR) values. Retrieved January 2, 2018 from

423

https://www.arb.ca.gov/regact/2009/mir2009/mir2009.htm

424

28. Carter, W. (1998). Development and application of an updated photochemical mechanism for

425

VOC reactivity assessment. Retrieved January 2, 2018 from

426

https://www.arb.ca.gov/research/apr/past/a932-094a.pdf

427

29. Carter, W. P. L. (2010). Updated maximum incremental reactivity scale and hydrocarbon bin

428

reactivities for regulatory application. Retrieved January 2, 2018 from

429

http://www.cert.ucr.edu/~carter/SAPRC/MIR10.pdf

20 ACS Paragon Plus Environment

Page 21 of 28

430

Journal of Agricultural and Food Chemistry

FIGURE CAPTIONS

431 432

Figure 1. Experimental set up for the two farms with sampling points (purple dots). Farm 1 was

433

equipped with three sampling towers (T1, T2, and T3) deployed at distances of 2, 6, and

434

20 m to the primary fan. The sampling heights on the towers were: T1 (1, 2, 4.5, 7.25,

435

and 10 m); T2 (1, 2, 4.5, and 7.25 m); and T3 (2, 4.5, 7.25, and 10 m). A 3-m change in

436

elevation existed between T1 and T3. Farm 2 was equipped with three sampling towers

437

(T1, T2, and T3) deployed at distances of 2, 23, 47 m to the primary fan. The sampling

438

heights on three towers were the same: 2 m, 4.5 m, 7.25 m, and 10 m.

439

Figure 2. Examples of the methanol relative concentration gradient a) daytime at Farm 1; b)

440

nighttime at Farm 1; c) daytime at Farm 2; d) nighttime at Farm 2. All concentrations

441

were normalized using the concentration of the 2-m height sampler on Tower 1 (T1-2 for

442

Farm 1 and T1-1 for Farm 2) from the same experiment.

443

Figure 3. Examples of the ethanol relative concentration gradient: a) daytime at Farm 1; b)

444

nighttime at Farm 1; c) daytime at Farm 2; d) nighttime Farm 2. All concentrations were

445

normalized using the concentration of the 2-m height sampler on Tower 1 (T1-2 for Farm

446

1 and T1-1 for Farm 2) from the same experiment.

447

Figure 4. Example of the butanol relative concentration gradient at Farm 1. Concentrations at

448

Farm 2 were only observed at less than 5% of the samplers and are not shown. All

449

concentrations were normalized using the concentration of the 2-m height sampler on

450

Tower 1 (T1-2) from the same experiment.

451

21 ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

452

Page 22 of 28

TABLE

453 454

Table 1. Photochemical properties of poultry emitted VOCs at a height of 2 m.

455 VOCs

Methanol

Ethanol

Acetone

Distance

Avg. Conc.

10-12 * kOH b

(m)

(µg/m3)

(cm3mol-1s-1)

Farm 1

Farm 2

2

194 ± 37

111 ± 23

~ 20 a

62 ± 34

47± 23

2

27 ± 10

47 ± 12

~ 20 a

24 ± 25

17 ± 11

2

24 ± 110

40 ± 12

~ 20 a

31 ± 41

MIR c

1.06

3.74

0.63

0.67

1.53

0.56

26 ± 18

Prop-Equiv

OFP

(µg/m3)

(µg/m3)

Farm 1

Farm 2

Farm 1

Farm 2

7.9 ± 1.5

4.5± 0.9

130 ± 25

75± 16

2.5 ± 1.4

3.0 ± 1.7

41 ± 23

49 ± 27

3.9 ± 1.5

6.7 ± 1.7

41 ± 16

71 ± 18

3.5 ± 3.6

3.8 ± 1.9

37 ± 38

40 ± 20

0.6 ± 0.2

1.0 ± 0.3

13 ± 6

22 ± 7

0.7 ± 1.0

0.7 ± 0.4

17 ± 23

17 ± 19

456

a

Farm 1: 20-m distance to the primary fan; Farm 2: 23-m distance to the primary fan

457

b

OH radical rate constant at 298 K [6]

458

c

Maximum incremental reactivity [(g O3 formed) (g VOC)-1] [7]

22 ACS Paragon Plus Environment

Page 23 of 28

Journal of Agricultural and Food Chemistry

459

23 ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

Figure 1. Experimental set up for the two farms with sampling points (purple dots). Farm 1 was equipped with three sampling towers (T1, T2, and T3) deployed at distances of 2, 6, and 20 m to the primary fan. The sampling heights on the towers were: T1 (1, 2, 4.5, 7.25, and 10 m); T2 (1, 2, 4.5, and 7.25 m); and T3 (2, 4.5, 7.25, and 10 m). A 3-m change in elevation existed between T1 and T3. Farm 2 was equipped with three sampling towers (T1, T2, and T3) deployed at distances of 2, 23, 47 m to the primary fan. The sampling heights on three towers were the same: 2 m, 4.5 m, 7.25 m, and 10 m.

ACS Paragon Plus Environment

Page 24 of 28

Page 25 of 28

Journal of Agricultural and Food Chemistry

Figure 2. Relative methanol concentration gradient a) daytime at Farm 1; b) nighttime at Farm 1; c) daytime at Farm 2; d) nighttime at Farm 2. All concentrations were normalized using the concentration of the 2-m height sampler on Tower 1 (T1-2 for Farm 1 and T1-1 for Farm 2) from the same experiment.

ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

Figure 3. Ethanol relative concentration gradient: a) daytime at Farm 1; b) nighttime at Farm 1; c) daytime at Farm 2; d) nighttime Farm 2. All concentrations were normalized using the concentration of the 2-m height sampler on Tower 1 (T1-2 for Farm 1 and T1-1 for Farm 2) from the same experiment.

ACS Paragon Plus Environment

Page 26 of 28

Page 27 of 28

Journal of Agricultural and Food Chemistry

Figure 4. Typical butanol relative concentration gradient at Farm 1. All concentrations were normalized using the concentration of the 2-m height sampler on Tower 1 (T1-2) from the same experiment.

ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

ACS Paragon Plus Environment

Page 28 of 28