Source identification and quantification of particulate matter emitted from livestock houses

Abstract

It is necessary to accurately identify and quantify sources which contribute to particulate matter (PM) emissions from livestock houses to develop adequate reduction strategies. To identify and quantify the contribution of different sources to fine (PM2.5) and coarse (PM10-2.5) PM emissions from poultry and pig houses, we compared the chemical and morphological characteristics of fine and coarse PM from known sources collected from livestock houses with the characteristics of on-farm fine and coarse airborne PM. Two methods were used to estimate source contributions: classification rules based on decision trees and multiple linear regression. Results showed that in poultry houses, most on-farm airborne PM originates from feathers (ranging from 4 to 43% in fine and from 6 to 35% in coarse PM) and manure (ranging from 9 to 85% in fine and from 30 to 94% in coarse PM). In broilers and turkeys, wood shavings contribute less than 34% of particle numbers. In pigs, most on-farm airborne PM originates from manure (ranging from 70 to 98% in fine and from 41 to 94% in coarse PM). The contributions of wood shavings in poultry and skin in pigs were less than 34%, varying with livestock categories. The contribution of manure to on-farm airborne PM was higher in coarse PM in poultry, but higher in fine PM in pigs. Feed had a negligible contribution to on-farm airborne PM compared with the rest of the sources. Results presented in this study improve the understanding of where PM comes from in different livestock housing systems. This can be valuable to choose the optimal dust reduction methods.