Periodic Reporting for period 2 - NaPuE (Impact of Nanoplastics Pollution on aquatic and atmospheric Environments)
Reporting period: 2023-03-01 to 2024-08-31
The global production of plastics is increasing annually and exceeded 400 Mt in 2022. The large production of plastic is associated with a diffusion of plastic pollution and environmental problems related to plastic contamination. A huge amount of plastic reaches the environment, and it starts a very slow process of degradation. This degradation process leads to fragmentation of plastics in small pieces which may be invisible to naked eye, the smallest plastic debris are called nanoplastics (size below 1 µm) and they may have a different behavior in the environment compared to the larger plastic debris. Indeed, it is expected to have higher nanoplastics concentrations (in number) than microplastics in the environment and to be more reactive due to their larger surface-to-volume ratio. NaPuE project is investigating the fate of nanoplastics in the environment and is developing methods to analyze nanoplastics in natural waters and in the atmosphere.
The outcome of NaPuE will provide information about the environmental fate of nanoplastics and it will significantly contribute to open new horizons to develop further research in this direction. In general, data on nanoplastic behavior are needed to evaluate the environmental impact of nanoplastics, this information is crucial to design solutions to decrease the effects of nanoplastic pollution and to contribute to policy decisions about plastic pollution.
NaPuE project has four main objectives to improve the knowledge of nanoplastic behavior in the environment:
1- To study the abiotic degradation of nanoplastics dispersed in water.
2- To understand the interactions between nanoplastics and compounds in the gas phase (such as trace gases, e.g. ozone).
3- To develop a new procedure to sample and analyze nanoplastics in the environment.
4- To develop models to simulate and predict nanoplastic reactivity in the environment.
The outcome of NaPuE will provide information about the environmental fate of nanoplastics and it will significantly contribute to open new horizons to develop further research in this direction. In general, data on nanoplastic behavior are needed to evaluate the environmental impact of nanoplastics, this information is crucial to design solutions to decrease the effects of nanoplastic pollution and to contribute to policy decisions about plastic pollution.
NaPuE project has four main objectives to improve the knowledge of nanoplastic behavior in the environment:
1- To study the abiotic degradation of nanoplastics dispersed in water.
2- To understand the interactions between nanoplastics and compounds in the gas phase (such as trace gases, e.g. ozone).
3- To develop a new procedure to sample and analyze nanoplastics in the environment.
4- To develop models to simulate and predict nanoplastic reactivity in the environment.
We have investigated the reactivity of several nanoplastics dispersed in water towards light and/or oxidants. In particular, we have studied the degradation of nanoplastics under simulated sunlight irradiation, in presence of oxidants (such as hydroxy radicals), metals, organic compounds and trace gases. We have developed a kinetic model to calculate the reaction rate (and the second order kinetic constant) of the studied processes, which give a quantitative information on the plastic transformation. These studies help to elucidate the fate of nanoplastics in the environment and they lay the basis to simulate and predict their degradation in the environment.
To evaluate the environmental impact of nanoplastics it is important to assess the type and amount of nanoplastic in environmental samples. Therefore, we have developed a new method to analyse nanoplastics following a procedure which consist of staining plastic particles with Nile-Red and detecting them by flow cytometry. This method allows for cheap and rapid (around 90 second for each analysis) detection and quantification of several polymers (nano and micro size).
To evaluate the environmental impact of nanoplastics it is important to assess the type and amount of nanoplastic in environmental samples. Therefore, we have developed a new method to analyse nanoplastics following a procedure which consist of staining plastic particles with Nile-Red and detecting them by flow cytometry. This method allows for cheap and rapid (around 90 second for each analysis) detection and quantification of several polymers (nano and micro size).
The development of a kinetic model to calculate second order kinetic constants between plastic particles and reactive species is an important achievement in the project. The development of this method was among the objectives of NaPuE project and allowed for the first time to measure and calculate the kinetic constants of nanoplastics degradation induced by oxidants.
The second achievement reached is the development of a method based on flow cytometry to analyze nanoplastics; it was among the high-risk high-gain objectives of the project. The method needs to be improved and further development of sample preparation is required to be able to apply this technique to several types of samples containing small plastic particles. However, the results we obtained are really promising for a fast and cheap analysis of nanoplastics.
The second achievement reached is the development of a method based on flow cytometry to analyze nanoplastics; it was among the high-risk high-gain objectives of the project. The method needs to be improved and further development of sample preparation is required to be able to apply this technique to several types of samples containing small plastic particles. However, the results we obtained are really promising for a fast and cheap analysis of nanoplastics.