A short review of bioaerosol emissions from gas bioreactors: Health threats, influencing factors and control technologies

Abstract

h i g h l i g h t sThe biofiltration generally emit more than 10 4 CFU m À3 bioaerosol. The bioaerosol emitted from the biofiltration is a potential threat to human body. Shear force and dilution affect the concentration of bioaerosol emissions. PCD is promising to control bioaerosols because of few secondary pollutants. a b s t r a c tBioaerosols have widely been a concern due to their potential harm to human health caused by the carrying and spreading of harmful microorganisms. Biofiltration has been generally used as a green and effective technology for processing VOCs. However, bioaerosols can be emitted into the atmosphere as secondary pollutants from the biofiltration process. This review presents an overview of bioaerosol emissions from gas bioreactors. The mechanism of bioaerosols production and the effect of biofiltration on bioaerosol emissions were analyzed. The results showed that the bioaerosol emission concentrations were generally exceeded 10 4 CFU m À3 , which would damage to human health. Biomass, inlet gas velocity, moisture content, temperature, and some other factors have significant influences on bioaerosol emissions. Moreover, as a result of the analysis done herein, different inactivation technologies and microbial immobilization of bioaerosols were proposed and evaluated as a potential solution for reducing bioaerosols emissions. The purpose of this paper is to make more people realize the importance of controlling the emissions of bioaerosols in the biofiltration process and to make the treatment of VOCs by biotechnology more environmentally friendly. Additionally, the present work intends to increase people's awareness in regards to the control of bioaerosols, including microbial fragment present in bioaerosols.

Bioaerosols in the landfill environment: an overview of microbial diversity and potential health hazards

“…Most researchers from countries with temperate or continental climates reported higher fungal aerosols during the warm season compared to the cold season (Cyprowski et al 2019 ; Fernanda et al 2020 ; Fraczek et al 2017 ; Madhwal et al 2020 ). The humid environment supports maximum growth of bacteria, while fungi proliferate quickly in a dry environment (Hu et al 2020 ). High relative humidity facilitates the fungal species to breed and form more compact colonies, leading to the lower release of fungal propagules into the atmosphere (Breza-Boruta 2016 ; Vilavert et al 2012 ).…”

Pathogens inactivation in nutrient recovery from urine: A review

“…Several factors involved in the evaporation/distillation of urine can inactivate pathogens. High temperature is highly effective to inactivate pathogens as reported in the fields of waste composting or water disinfection (Chu et al, 2019;Hu et al, 2020). Moreover, Bethune et al (2014) suggested that the urine-derived solid product was sterile because high salinity in the concentrated product might respond for the inactivation of microorganisms.…”

Cyclohexane removal and UV post-control of bioaerosols in a combination of UV pretreatment and biotrickling filtration

“…According to China's "Indoor Air Quality Standards" (GB/T 18883-2002), the bioaerosol concentrations of the three sampling sites at each airspeed belonged to the "clean level" (the total bioaerosols <3,000 CFU m −3 , bacteria <1,000 CFU m −3 , fungi <500 CFU m −3 ). Hu et al (2020) showed that the concentration of bioaerosols emitted from bioreactors ranges from 10 3 to 10 6 CFU m −3 . Zhang et al (2017) detected that the average annual bacterial concentration of airborne bioaerosols in the Beijing-Tianjin-Hebei region was 1,380-3020 CFU m −3 and fungi were 89-2270 CFU m −3 .…”