Bacterial community in household municipal solid waste and bioaerosols released: Implications to health risks

Household municipal solid waste (HMSW) is a heterogeneous stream rich in moisture and organic matter, creating favorable conditions for microbial proliferation, including potentially pathogenic bacteria posing risks to human health. This study characterized microbial communities in solid waste and aerosols emitted from household waste bins of residential areas, indicating that the bacterial community in aerosols exhibits higher diversity and richness (177 % higher) compared to that in HMSW. The environmental response analysis shows that natural factors shape the waste community in a complex and indirect route, while bacteria in the solid waste significantly influenced the surrounding background structure of the aerosol community. Furthermore, 36 risk-associated bacterial species were identified, with 14 exhibiting a high aerosolization potential (Aerosolization Index >1). Quantitative microbial risk assessment was made for two typical risk species, Acinetobacter baumannii and Klebsiella pneumoniae. The annual human health guard rate shows that Acinetobacter baumannii pose a notable health risk to residents (71.02 %), and both the two is potentially harmful to professionals (0 % and 1.17 %), highlighting the need for vigilance regarding microbial exposure from HMSW. The study provides fundamental data on risk bacteria and their environmental behavior, offering valuable insights for improving waste management strategies and mitigating public health risks.