Organic micropollutants, heavy metals and pathogens in anaerobic digestate based on food waste
Golovko, Oksana; Ahrens, Lutz; Schelin, Jenny; Sörengård, Mattias; Bergstrand, Karl-Johan; Asp, Håkan; Hultberg, Malin; Wiberg, KarinAbstract
Anaerobic digestate based on food waste is increasingly used as fertilizer in food production. This study examined the characteristics of anaerobic digestate based on food waste from three biogas plants in Sweden. The characterization included measurements of heavy metals (n = 7), chemicals of emerging concern (CECs), such as currently used drugs and pesticides (n = 133), and an extended range of food-borne pathogens, including two notable sporeformers and some widespread antibiotic-resistant bacteria. The amounts of Escherichia coli, enterococci, and Salmonella and the concentrations of the target heavy metals were all below the maximum accepted levels at all three locations studied. However, the spore-forming Bacillus cereus was found to be present at high levels in samples from all three biogas plants. Among the 133 CECs investigated, 48 were detected at least once, and the highest concentrations were found for pyroxidine, nicotine, caffeine, theobromine, and nicotine. The biofertilizers from the different biogas plants had similar CEC profiles, which indicate similarities in household waste composition and thorough mixing in the biogas plants. If this profile is found to be spatially and temporally consistent, it can help regulators to establish priority lists of CECs of top concern. Assuming increasing use of biofertilizers for food production in the future, it would be beneficial to have concentration limits for CECs Risk estimation based on risk quotients (RQs) indicated generally low environmental risks associated with application of biofertilizer to soils for food crop production. However, the toxicity of CEC mixtures needs to be considered when estimating the risks from application of biofertilizers on agricultural land or in other production systems.
Keywords
Biofertilizer; Food waste; Risk assessment; Heavy metals; CECsPublished in
Journal of Environmental Management2022, volume: 313, article number: 114997
Authors' information
Associated SLU-program
Food Waste
Sustainable Development Goals
SDG2 Zero hunger
SDG12 Ensure sustainable consumption and production patterns
UKÄ Subject classification
Environmental Sciences related to Agriculture and Land-use
Publication Identifiers
DOI: https://doi.org/10.1016/j.jenvman.2022.114997
URI (permanent link to this page)
https://res.slu.se/id/publ/116903