On May 17, 2021, Chemosphere published a review article in which Anabel Gonzáles-Acedo and co-authors from the University of Granada, Spain, give an overview on the potential human health impacts of microplastics and nanoplastics (FPF reported) based on evidence from in vitro and in vivo studies.
According to the scientists’ literature review, plastic particles induced inflammation, cytotoxic and genotoxic effects in different cell lines. In vivo studies with mussel, fish, and rat species demonstrated that micro- and nanoplastics can be absorbed and accumulated in different organs and systems in a size-dependent manner. Upon absorption through cell membranes, the plastic particles have been reported to alter normal cell functioning. As summarized in the article, this can result in “changes in microbiota and digestive enzyme production; inflammatory processes at respiratory level; circulatory and reproductive system disorders; and neurotoxicity, inducing behavioral changes.” The review makes clear that in vitro and in vivo uptake and effects of micro- and nanoplastics largely depend on particle size, surface charge, and concentration. The authors concluded that further research is needed to investigate potential human health implications at environmentally relevant particle concentrations and to determine how particle size and amounts influence these effects.
Another article published online on July 23, 2021, in Critical Reviews in Environmental Science and Technology by Qingying Shi and colleagues from Nankai University, Tianjin, China, also reviewed the in vitro toxicity of micro- and nanoplastics and came to similar conclusions. In addition to the concerns mentioned by Gonzáles-Acedo et al., this review also touched upon the toxicity of plastic chemicals and absorbed contaminants found to induce cytotoxicity (FPF reported), and emphasized the importance to distinguish between chemical- and particle-related toxicity. According to the authors, long-term exposure studies are needed, and future research should also reflect the diversity of particles present in the environment instead of focusing predominantly on spherical polystyrene micro- and nanoplastics.
Five recently launched Horizon 2020 research projects funded by the European Commission are working to better understand micro- and nanoplastic effects on human health (FPF reported).
Gonzáles-Acedo et al. (2021). “Evidence from in vitro and in vivo studies on the potential health repercussions of micro- and nanoplastics.” Chemosphere (available online May 17, 2021).
Shi et al. (2021). “Toxicity in vitro reveals potential impacts of microplastics and nanoplastics on human health: A review.” Critical Reviews in Environmental Science and Technology (available online July 23, 2021).