Characteristics of PM2.5 and Its Correlation with Feed, Manure and NH3 in a Pig-Fattening House

Shihua Pu; Siyi Peng; Jiaming Zhu; Zuohua Liu; Dingbiao Long; TengTeeh Lim

doi:10.3390/toxics10030145

Characteristics of PM_2.5 and Its Correlation with Feed, Manure and NH3 in a Pig-Fattening House

Toxics. 2022 Mar 19;10(3):145. doi: 10.3390/toxics10030145.

Authors

Shihua Pu^{1

2

3}, Siyi Peng^{1

4}, Jiaming Zhu^{1

2

3}, Zuohua Liu^{1

4}, Dingbiao Long^{1

2

3}, TengTeeh Lim⁵

Affiliations

¹ Chongqing Academy of Animal Sciences, Changlong Avenue, Rongchang District, Chongqing 402460, China.
² Scientific Observation and Experiment Station of Livestock Equipment Engineering in Southwest, Ministry of Agriculture and Rural Affairs, Chongqing 402460, China.
³ Innovation and Entrepreneurship Team for Livestock Environment Control and Equipment R&D, Chongqing 402460, China.
⁴ College of Animal Science and Technology, Southwest University, Chongqing 402460, China.
⁵ Division of Food Systems and Bioengineering, University of Missouri, Columbia, MO 65211, USA.

Abstract

Fine particulate matter (PM), including PM_2.5 in pig houses, has received increasing attention due to the potential health risks associated with PM. At present, most studies have analyzed PM_2.5 in Chinese pig houses utilizing natural ventilation. These results, however, are strongly affected by the internal structure and regional environment, thus limiting their applicability to non-mechanically ventilated pig houses. This experiment was carried out in an environmentally controlled pig house. The animal feeding operation and manure management in the house were typical for Southwest China. To reduce the influence of various environmental factors on PM_2.5, the temperature and humidity in the house were maintained in a relatively stable state by using an environmental control system. The concentration of PM_2.5 in the pig house was monitored, while the biological contents and chemical composition of PM_2.5 were analyzed, and feed, manure, and dust particles were scanned using an electron microscope. Moreover, bacterial and fungal contents and some water-soluble ions in PM_2.5 were identified. The results showed that the concentration of PM_2.5 in the pig house was strongly affected by pig activity, and a phenomenon of forming secondary particles in the pig house was found, although the transformation intensity was low. The concentration of PM_2.5 had negative correlations of 0.27 and 0.18 with ammonia and hydrogen sulfide, respectively. Interestingly, a stronger correlation was observed between ammonia and hydrogen sulfide and ammonia and carbon dioxide concentrations (the concentration of ammonia had stronger positive correlations with hydrogen sulfide and carbon dioxide concentrations at +0.44 and +0.59, respectively). The main potential sources of PM_2.5 production were feed and manure. We speculate that manure could contribute to the broken, rough, and angular particles that formed the pig house PM_2.5 that easily adhered to other components.

Keywords: air pollutants; particulate matter; potential sources; primary particles; secondary particles.

Abstract

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