Most scientific work on the movement of micro- and nanoplastics focuses on the size and shape of the particles. However, other properties, such as physico-chemical properties, can strongly influence the particles' effects. Many studies work with industrially manufactured particles, mainly polystyrene spheres. But the particles occurring in the environment have a huge variety of properties. There is a broad consensus in research that the smaller the particles, the more often they interact with human tissue and individual cells. Biological barriers play a decisive role here: they prevent larger particles from penetrating tissues.
However, the authors of the new study point out an inconsistency. In some human tissue samples, the described particle exceeds the particle sizes for potential tissue translocation. One plausible explanation would be the contamination of the samples during sample processing. In addition, the research literature reviewed contains numerous indications that measures for quality assurance and quality control of samples have been insufficiently implemented and described.
In its study, however, the "PlasticsFatE" team also summarizes several fundamental findings about which there is no longer any doubt today: In most regions of the world, people's everyday lives contain increasing amounts of micro- and nanoplastics. The particles can enter the body through drinking water, food, inhaled air and cosmetics. Micro- and nanoplastic particles are taken up by humans mainly through the respiratory and gastrointestinal tract.
"Both at the European level and in the recently extended SFB 1357 'Microplastics' at the University of Bayreuth, we will intensively investigate the interactions between microplastics and organisms in the upcoming years. We aim to obtain reliable hazard assessments from which effective risk reduction measures can be derived. In doing so, however, we have to reckon with the fact that there may be long-term consequences of environmental contamination by plastics which are only rudimentarily recognisable today," says Laforsch.
Publication:
Anja F.R.M. Ramsperger et al.: Nano- and microplastics: a comprehensive review on their exposure routes, translocation, and fate in humans. NanoImpact 29 (2023) 100441. DOI: https://doi.org/10.1016/j.impact.2022.100441