Assessment of bioaerosol emissions from composting application in the urban green space of Kermanshah province in Iran

The vast majority of microorganisms in composting sites produce aerosols, which can cause respiratory difficulties. The objective of this study was to evaluate the emission of bioaerosols from compost applications in urban green space and assess their potential health hazards. The biological samples of bacteria and fungi in the air were collected in 20 points of the urban green space. Fungal medium and bacterial medium has been used as two plates containing the same medium to identify the bacteria and fungi in the air. The ambient temperature and humidity were measured at each of the 20 points of the sampling sites. The obtained results showed that the average concentration of bacteria and fungi in the background samples (before compost application) were 1108 and 122 CFU/m3, respectively. The bacterial and fungal concentration increased three times in the main samples (bacteria: 8393 CFU/m3 and fungi: 1659 CFU/m3) and increased relatively two times in the downwind samples at a distance of 10 m. Although the airborne fungal concentration in the main samples increased three times more than the background samples, a significant statistical difference was not verified between these values. As a result, the increasing of airborne fungi from compost application cannot be proven with certainty. Compost application in the urban green space is considered as the potential source for pathogenic bacteria emission.