Microbial Aerosols: Sources, Properties, Health Effects, Exposure Assessment—A Review

Abstract

Microorganisms are ubiquitous in the environment. Wherever their sources are present, the particles can be released into the air forming microbiological aerosols. Although most of their particles cause no harm to the exposed individuals, some of their propagules may have infectious or allergenic potential and may carry toxic or irritant substances and components. Their inhalation usually poses a significant health risk and is responsible for numerous adverse outcomes, from allergic reactions, infections and toxic responses to various nonspecific symptoms. This review article provides fundamental background information on the role of microorganisms in the environment, defines and characterizes environmental sources of microbial aerosols, describes microbial abilities for airborne transport and comments on their role in atmospheric processes, discusses their physical and biological characteristics which result in adverse health outcomes observed in exposed individuals. The paper characterizes comprehensively numerous sampling and analysis techniques involved in the quantitative and qualitative evaluation of microbial aerosols together with their practical applications, presents strategies applied in the assessment of harmful microbial agents formed by bioaerosols, explains the ways of creating hygienic standards (understood here as reference/threshold limits) for microbiological aerosols conditioned by both medical and environmental determinants, and comments on their usefulness in the control and protection of environment and health.

Size distribution and concentration of fungal aerosol in animal premises of a zoological garden

“…In order to do this, the levels of concentration of biological factors, usually occurring in public utility premises, are determined based on repeated measurements. Those are used to determine The recommendations do not apply to specific animals or people, but to two groups of premises-work rooms polluted with organic dust and to residential and public utility facilities Górny 2019). Only in two cases, i.e., in the enclosures for ostriches and in exotarium, the values observed in autumn (1.71 9 10 4 CFU/m 3 and 2.84 9 10 4 CFU/m 3 , respectively) exceeded the proposed limit value for fungal aerosol.…”

Size distribution of microbial aerosols in overground and subterranean treatment chambers at health resorts

“…Regardless of the season, the level of indoor bacterial contaminants was always significantly higher than this observed in atmospheric (outdoor background) air insufficient to quantitatively and qualitatively characterize them. If threshold limit or reference values are established, they are usually connected with the clinical picture of specific disease caused by the agent, taking into consideration its presence in a certain element of the environment only [28,29]. Nevertheless, despite these limitations, the reference values expressed in numbers are available and usually applied to facilitate interpretation of the measurement data.…”

Air pollution and its impact on the concentration of airborne fungi in the megacity of São Paulo, Brazil

“…Megacities around the world might present severe air quality issues, as a result of the rapid urban development ( Romieu et al., 2012 ; Slovic and Ribeiro, 2018 ). The current air pollution levels may compromise the health of the population in a large scale due to the exposure to hazardous compounds ( César et al., 2016 ; Oliveira et al., 2018 ; Rojas et al., 2019 ; Górny, 2020 ).…”