The COVID-19 pandemic has brought to light the urgent need for personal protective equipment (PPE) and has also exacerbated the ongoing issue of plastic pollution as a result. The increased use of plastic PPE, combined with the use of antibiotics and antiviral pharmaceuticals in hospitals to treat COVID-19 patients and the unregulated use of these substances in households, has resulted in the release of large amounts of contaminants into rivers and coastal waters [1-3].
The current understanding of the impact of nano/micro-sized plastics and pharmaceuticals, particularly those used for COVID-19 treatment and prevention, on aquatic organisms and the environment is limited. More research is needed to determine the physico-chemical changes of these new contaminants, their penetration abilities through the protective barriers of organisms, and the health status of these organisms. Our study aimed to investigate the bioaccumulation and acute toxicity of different size carboxylate-modified nano/microplastics in combination with the pharmaceutical hydroxychloroquine on Salmo trutta embryos and larvae. The results of spectroscopic measurements showed that the stability of the colloidal plastics exhibited a size-dependent pattern. By using confocal fluorescence microscopy, we demonstrated that nano/microplastics in combination with hydroxychloroquine could penetrate through the external protective tissues of embryos and larvae. Additionally, we found that changes in the biological parameters of the exposed organisms depend on the type of chemical material, the duration of treatment and the stage of development of the affected organisms. The findings of this study highlight the need for further research on the long-term impact of nano/microplastics on aquatic organisms, particularly on the potential interactions between these particles and other contaminants. This will help in the development of more effective management strategies to mitigate the negative effects of pollution arising during emergency situations.