Physical, chemical, and microbial contaminants in food waste management for soil application: A review

James O'Connor; Bede S Mickan; Kadambot H M Siddique; Jörg Rinklebe; M B Kirkham; Nanthi S Bolan

doi:10.1016/j.envpol.2022.118860

Physical, chemical, and microbial contaminants in food waste management for soil application: A review

Environ Pollut. 2022 May 1:300:118860. doi: 10.1016/j.envpol.2022.118860. Epub 2022 Feb 1.

Authors

James O'Connor¹, Bede S Mickan², Kadambot H M Siddique³, Jörg Rinklebe⁴, M B Kirkham⁵, Nanthi S Bolan⁶

Affiliations

¹ School of Agriculture and Environment, The University of Western Australia, Perth, WA, 6001, Australia; Cooperative Research Centre for High Performance Soil (Soil CRC), The University of Newcastle, Callaghan, NSW, 2308, Australia.
² School of Agriculture and Environment, The University of Western Australia, Perth, WA, 6001, Australia; The UWA Institute of Agriculture, The University of Western Australia, Perth, WA, 6001, Australia.
³ The UWA Institute of Agriculture, The University of Western Australia, Perth, WA, 6001, Australia.
⁴ University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water and Waste Management, Laboratory of Soil and Groundwater Management, Pauluskirchstraße 7, 42285, Wuppertal, Germany; Department of Environment, Energy and Geoinformatics, Sejong University, 98 Gunja-Dong, Guangjin-Gu, Seoul, Republic of Korea. Electronic address: rinklebe@uni-wuppertal.de.
⁵ Department of Agronomy, Kansas State University, Manhattan, KS, 66506, United States.
⁶ School of Agriculture and Environment, The University of Western Australia, Perth, WA, 6001, Australia; Cooperative Research Centre for High Performance Soil (Soil CRC), The University of Newcastle, Callaghan, NSW, 2308, Australia; The UWA Institute of Agriculture, The University of Western Australia, Perth, WA, 6001, Australia.

PMID: 35114306
DOI: 10.1016/j.envpol.2022.118860

Abstract

Currently, 1.3 billion tonnes of food are thrown away each year, most of which are incinerated or landfilled causing large environmental, social, and economic issues. Therefore, the utilisation of food waste as biofertilisers, such as composts and digestates, is a solution to reduce the problems created by incineration and landfilling whilst simultaneously amending soils. The improper disposal of food wastes and bulking materials can contribute to high levels of contaminants within the end-product. Moreover, the food waste and bulking materials, themselves, may contain trace amounts of contaminants. These contaminants tend to have long half-lives, are easily mobile within soil and plants, can accumulate within the food supply chain, and have moderate to high levels of toxicity. This review aims to examine the current and emerging contaminants of high concern that impact the quality of food-waste fertilisers. The paper presents the volume of current and emerging contaminants of plastics, other physical (particulate) contaminants, heavy metals, pesticides, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), per- and polyfluoroalkyl substances (PFAS), and pathogens within food-waste composts and digestates. Due to the large extent of organic chemical contaminants and the unknown level of toxicity and persistence, the risk assessment of organic chemical contaminants in the food-supply chain remains largely unknown. This study has presented available data from literature of various contaminants found in food waste, and composts and digestates derived from food waste, and evaluated the data with current regulations globally. Overall, to reduce contaminants in composts and digestates, more studies are required on the implementation of proper disposal separation, effective composting and digestion practices, increased screening of physical contaminants, development of compostable plastics, and increased regulatory policies on emerging, problematic contaminants. Moreover, examination of emerging contaminants in food-waste composts and digestates is needed to ensure food security and reduce future human-health risks.

Keywords: Anaerobic digestion; Chemical contaminants; Compost; Food waste; Microbial contaminants; Physical contaminants.

Publication types

Review

MeSH terms

Composting*
Food
Humans
Refuse Disposal*
Soil
Waste Management*

Substances

Soil