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Micro and nanoplastics in the environment: Research priorities for the near future

  • May 2021
DOI: 10.5281/zenodo.4767185
Authors:
Marco Vighi at Università degli Studi di Milano-Bicocca
Marco Vighi
Javier Bayo at Universidad Politécnica de Cartagena
Javier Bayo
Francisca Fernandez-Piñas at Universidad Autónoma de Madrid
Francisca Fernandez-Piñas
J. Gago at Instituto Español de Oceanografia
J. Gago
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... For the case of the biodegradable plastic PLA, the fluorescent signal in the protein-like region slightly decreased in both irradiated (-6.13 ± 1.07 RU⋅nm 2 ) and dark treatments (-8.55 ± 1.91 RU⋅nm 2 ) with no significant differences between them. This indicates that PLA could be adsorbing some of the FDOM present in seawater since it is known that plastic can adsorb organic substances such as persistent organic pollutants (Vighi et al., 2021). ...
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... The ubiquitous presence of microplastics (MPs) in all the environments (water, soil and air), as well as in biota, is becoming more and more evident as a result of the intense research that is currently being developed by the scientific community (Ugbede et al., 2021;Vighi et al., 2021). In the particular case of the marine environment, in which highest number of published works have been based, the presence of MPs has been assessed in a good number of living organisms, being invertebrates the ones mostly studied (Ribeiro et al., 2019;Trestrail et al., 2020). ...
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Aquatic environments are generally contaminated with nanoplastic material. As a result, molecular mechanisms for sensitive species like Daphnia are needed, given that mechanistic nanoplastic toxicity is largely unknown. Here, global transcriptome sequencing (RNA-Seq) was performed on D. pulex neonates to quantitatively measure the expression level of transcripts. A total of 208 differentially expressed genes (DEGs) were detected in response to nanoplastic exposure for 96 h, with 107 being up-regulated and 101 down-regulated. The gene functions and pathways for oxidative stress, immune defense, and glycometabolism were identified. In this study, D. pulex neonates provide some molecular insights into nanoplastic toxicity. However, more studies on DEGs are needed to better understand the underlying mechanisms that result as a response to nanoplastic toxicity in aquatic organisms.
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