A quantitative assessment of plastic residues in Australian biosolids

Plastic debris is accumulating in the natural environment due to its limited recovery and durability. The breadth and scope of how plastics may be introduced into soil systems is not yet fully researched or understood, however it has been recognised worldwide that they can be introduced into soils through the common practice of applying biosolids (treated sewage sludge) to agricultural land. Agricultural soils in Australia annually receive about 176,000 tonnes of biosolids as soil amendments. The widespread use of biosolids for agricultural purposes could therefore be a potential opportunity for the release of plastics into receiving Australian agricultural soils, which could pose a greater risk to the soil ecosystem and humans. Nevertheless, we currently do not know how much plastics are in biosolids intended to be applied to agricultural soils across Australia. Accordingly, this study aims to determine the per capita mass and composition of plastics within biosolids samples intended for agricultural land applications in Australia using new techniques, to have a more comprehensive understanding of their fate.

Elvis Okoffo holds a Bachelor’s degree in Environmental Science from the University for Development Studies, Ghana and a Master of Philosophy degree in Environmental Science from the University of Ghana. His PhD study focuses on assessing the risks associated with the land application of biosolids. Elvis is particularly interested in investigating the occurrence/incidence of contaminants of emerging concerns (CECs) and microplastics (MPs) in biosolids intended for land applications, their environmental fate, potential effects/risks on soil ecosystems and their associated human health implications/risks/toxicology.