The concern about plastic pollution has become widespread after it was realised that mismanaged plastics in the environment break down into smaller pieces known as microplastics and nanoplastics. It is likely that nanoplastics, due to their small size, can pass through physiological barriers and enter organisms.
Despite the growing body of evidence on the potential toxicity of nanoplastics to plants, invertebrates and vertebrates, our understanding of plastic transfer in food webs is limited. For instance, little is known about nanoplastics in soil ecosystems and their uptake by soil organisms, despite the fact that agricultural soil is potentially receiving nanoplastics from different sources such as atmospheric deposition, irrigation with wastewater, application of sewage sludge for agricultural purposes, and use of mulching film. Measurement of uptake of nanoplastics from the soil by plants, particularly vegetables and fruit in agricultural soils, is thus a critical step to reveal whether and to what extent nanoplastics can make their way into edible plants and, consequently, into food webs.
Researchers at the University of Eastern Finland have developed a novel, metallic fingerprint-based technique to detect and measure nanoplastics in organisms and, in this new study, they applied it to a model food chain consisting of three trophic levels, i.e., lettuce as a primary producer, black soldier fly larvae as a primary consumer, and the insectivorous fish (roach) as a secondary consumer. The researchers used commonly found plastic waste in the environment, including polystyrene (PS) and polyvinyl chloride (PVC) nanoplastics.
Read more at: University of Eastern Finland
Test site where extra carbon dioxide is emitted to the air and the biomass growth is measured in the plants. (Photo Credit: Louise C Andresen)