Distribution patterns and influencing factors of pathogenic microbial communities in household municipal solid waste: A case in Beijing, China

Household municipal solid waste (MSW) provides a suitable environment for the propagation and emission of pathogens, and revealing their distribution patterns and influencing factors is important for source control of the potential risks. This study analyzed the microbial communities of pathogenic bacteria and fungi in MSW, by collecting both food waste and residual waste samples from a high-density residential area in Beijing for 11 months. Alpha diversity analysis indicated that the microbial diversity differed significantly between food waste and residual waste; however, Weissella and Candida were consistently detected at high proportions. In total, 43 pathogenic bacterial and fungal species each were detected. Candida albicans, Candida tropicalis, Enterococcus faecalis, Serratia liquefaciens, and Acinetobacter johnsonii were identified as core pathogens with high relative abundances and occurrence frequencies. While warmer seasons appeared to favor the accumulation of pathogens, no significant correlation between communities and seasons was found. Pathogenic microbial communities differed significantly among waste types, with relative abundances of bacterial pathogens being higher in residual waste than in food waste, and vice versa for fungal pathogens. Waste properties, including protein, carbon, and hydrogen contents and electrical conductivity are crucial in shaping the pathogenic microbial diversity, and environmental conditions including temperature, atmospheric pressure, and relative humidity also contribute. The findings in distribution patterns and influencing factors of pathogens in household MSW provide a scientific basis for the source control and further assessment of occupational health risks in waste management.