The full proceedings paper is at: http://www.extension.org/72731 The research community is making good progress in understanding the mechanical, biochemical, and atmospheric processes that are responsible for airborne emissions of particulate matter (PM, or dust) from open-lot livestock production, especially dairies and cattle feedyards. Recent studies in Texas, Kansas, Nebraska, Colorado, California, and Australia have expanded the available data on both emission rates and abatement measures. Although the uncertainties associated with our estimates of fugitive emissions are still unacceptably high, we have learned from our recent experience with ammonia that using a wide variety of credible measurement techniques, rather than focusing on one so-called “standard” technique, may be the better way to improve confidence in our estimates. Whereas the most promising control measures for gaseous emissions continue to be dietary strategies with management of corral-surface moisture a close second for particulate matter, corral-surface management and moisture management play comparable roles, depending on the mechanical strength of soils and the availability of water, respectively. The cost per unit reduction of emitted mass attributable to these abatement measures varies as widely as the emissions estimates themselves, so we need to intensify our emphasis on process-based emissions research to (a) reduce the variances in our emissions estimates and (b) mitigate the contingency of prior, empirically based estimates. As a general rule, although cattle feedyard emission factors may be thought a reasonable starting point for estimating emissions from open-lot dairies, such estimates should be viewed with suspicion.

1. Particulate Matter from
Open-Lot Dairies and
Cattle Feeding
Western Dairy Air Quality Symposium
2015 Waste to Worth Conference
Brent W. Auvermann

2. Agenda
• Recent feedyard work (2013-14)
• Survey most recent literature (2010-15)
 Measurement methods
 Aerosol concentrations
 Emission rates and fluxes
 Health-related studies

3. Historical U. S. Emission Factors (IDM)
0
10
20
30
40
50
60
70
80
AP-42 (vacated) S. Parnell et al.
(1994)
C. B. Parnell et al.
(1999)
CARB (2004) Lange et al.
(2007)
Wanjura et al.
(2004)*
PM10EmissionFactor(lb/1,000hd-d)

5. 75’ 75’50’ 50’30’ 30’
y

9. “El Nino” Has Not Been Helpful
• Rainiest June in many
years
• Consistent rains in
July
• Thunderstorm took
out one 50’ tower
• 7-acre pigweed-
control project

10. 0
20
40
60
80
100
WEST EAST AVG
PM10EmissionFactor(lb/1,000hd-d)
Day 1 Day 2

11. POLLUTAN
T
Beef Dairy Notes
PM10
(lb/1,000 hd-d)
9-70
(numerous
sources)
4.4 (TAMU);
6.7 (CARB);
11.5
(SJVAPCD,
FSB);
26.5
(SJVAPCD,
OL)
EPA vacated the AFO emission
factors in AP-42 in the most recent
revision; SJVAPCD recognizes
differences between FSBs and
open lots; no interspecies
difference in PM10/TSP ratio
NH3-N
45-55% of N
fed
(numerous
sources)
0.047 lb/hd-d
(Mukhtar et al.,
2008)
0.098 lb/hd-d
(Flesch et al.,
2009)
Dairy range 0.0074-0.258 across
multiple authors; most dairy results
not expressed in terms of % of N
fed; beef values appear to be less
variable (due to fewer
permutations of sources?)
H2S
(lb/1,000 hd-d)
8.9 (Casey,
2008)
0.07 to 60
Oregon DEQ chose 15.7 for dairy;
dairy estimates span 3 orders of
magnitude; open lot emission
fluxes are low, but aggregate rate
is >75% of total; per-head basis
not satisfactory for open lots

12. Dairy/Feedyard PM, 2011-
2015
A Survey of Recent Research

13. Search Criteria
• Multiple databases
 EBSCO
 JSTOR
 ScienceDirect
 Web of Science

14. Search Criteria
• Search string
 {dust or particulate or PM or
aerosol or fugitive} AND
 {drylot or open lot or dairy or
feedyard or feedlot}

15. Summary
• #1: BIOAEROSOLS (50%)
 Inflammatory agents and endotoxin
 Microbial speciation & persistence
 Endocrine activation

16. Ravva et al. (2011)
• PLoS ONE 6(2):1-9
• Bacterial RNA sequencing
 Sonoma dairy vs. Modesto dairy
 Manure bacteria vs. aerosol bacteria
• Predominant airborne bacteria are
NOT predominant bacteria in manure
• Location dependent (but n=2)

17. Dungan et al. (2011)
• Journal of Animal Sci. 89(10):3300-9
• 10,000-head open/free-stall dairy
• Endotoxin, bacteria, and fungi
• Upwind & downwind (50m, 200m)
 50m: elevated concentrations
 200m: near background concentrations
 Endotoxin and bacteria ONLY

18. Adapted from Dungan et al. (2011)

19. Summary
• #2: OCCUPATIONAL HEALTH (30%)
 Pulmonary function of workers
 Characterization of PM
 Occupational exposure
 Endotoxin
 SYSTEMATIC REVIEW – Reynolds et al., 2013

20. Reynolds et al. (2013)
• Journal of Agromedicine 18(3):219ff
• Lung disorders linked to endotoxin exp.
• Obstructive changes “generally mild”
• Emerging evidence beyond endotoxin
• Parlor washing has measurable effect
• Protective effect of early-life exposure

21. Summary
• #3: CONCENTRATION MEASURES (24%)
 Cow allergen and dust vs. distance (D)
 PM concentrations (FY)
 Elemental concentrations (D)
 Barn concentrations vs. animal activity (D)

22. Williams et al. (2011)

23. Joo et al. (2013)
• Free-stall dairy barn, Washington state
• Pronounced seasonality for PM10
• TSP (not PM2.5 or PM10) weakly
correlated with animal activity
• Emission rates: 26-33 lb/1,000 hd-d PM10

24. Guo et al. (2011)
• Cattle feedyards in Kansas
• Confirmed MC = 20% for dust control
• Overwhelming evidence of coarse PM
• FP ratios in feedyard dust < urban
 PM10/TSP = 0.41
 PM2.5/TSP = 0.10
 PM2.5/PM10 = 0.29*

25. Marchant et al. (2011)
• Dairy PM emission rates (open lot + FS)
• PM10 EF = 33-55 lb/1,000 hd-d
• Two techniques
 Lidar mass-balance technique
 Inverse dispersion modeling
• EF (lidar) = 0.6 EF (IDM) for PM10
• Will use lidar on TX feedyard in Spr ‘15

26. Conclusions
• Significant attention to bioaerosols,
public and occupational health
 Systematic reviews
 Public exposure monitoring
 In vitro bioactivity assays
 Microbial markers of livestock
• Alternatives to IDM for flux estimation