Odor nuisance, environmental impact and health risk of priority-controlled VOCs generated from three decentralized aerobic biological modes in treating rural perishable waste.

Utilization of perishable waste has emerged as the pivotal factor in enhancing the quality and efficiency of garbage classification in rural regions of China. Nevertheless, the operation of small-scale decentralized aerobic biological treatment facilities in rural areas will inevitably result in the emission of malodorous volatile organic compounds (VOCs). In this study, VOCs emission characteristics of three typical decentralized facilities for the treatment of perishable waste in rural areas were investigated using cold trap enrichment combined with gas chromatography and mass spectrometry to elucidate the characteristics and potential effects on environment and human health. The concentration range of different points in the mechanical composting (MC) treatment mode is from 43.555 to 4154.281 (mean value, 947.292) µg/m3, in the solar-assisted composting (SAC) it is from 99.050 to 2064.308 (636.170) µg/m3, and in the bioconversion by black soldier fly larvae (BBSF) it is 93.712 to 718.644 (283.444) µg/m3. Odor nuisance analysis showed that oxygenated compounds and aromatic compounds were the main odoriferous VOCs. Among all detected VOCs, o-xylene, toluene, and acrolein have the highest ozone formation potential (OFP). Toluene, ethyl benzene, and xylene are the VOCs with secondary organic aerosol generation potential (SOAP). Health risk analysis revealed that six VOCs collectively represent a potential carcinogenic risk, while acrolein exhibits a non-carcinogenic risk. In light of the odor nuisance, environmental impact, and potential health risk, the priority-controlled VOCs identified in decentralized aerobic treatment modes of rural perishable waste were acrolein, benzyl chloride, ethyl acetate, etc. The findings of this research can serve as a valuable reference for the selection of proper strategies in the precise control of VOCs.