Spatial tracking of microplastics in biological systems and tissues

• Grant number: 23/18229-6
• Support Opportunities: Regular Research Grants
• Start date: September 01, 2024
• End date: August 31, 2026
• Field of knowledge: Physical Sciences and Mathematics - Chemistry
• Principal Investigator: Walter Ruggeri Waldman
• Grantee: Walter Ruggeri Waldman
• Host Institution: Centro de Ciências e Tecnologias para a Sustentabilidade (CCTS). Universidade Federal de São Carlos (UFSCAR). Sorocaba , SP, Brazil
• Associated researchers: Abbas Sadeghzadeh Milani ; Adriana de Oliveira Delgado Silva

Abstract

Microplastics are emerging contaminants found in the air, soil, and water near or far from anthropogenic sources. Due to the lack of chemical contrast with the environment in which they are, microplastics are separated from the matrix to be analyzed, so information about their spatial distribution within tissues, organs, or biological systems is lost. In this proposal, we plan to use the additives in plastic products and packaging formulations as markers to contrast the microplastics and the media. Heavier elements, such as metals, present in inorganic pigments, and oxo-degradable additives allow the use of X-ray fluorescence spectroscopy to detect the presence of microplastics within biological tissues and X-ray computed microtomography to determine their spatial distribution within tissues or organs. This approach is suitable for laboratory studies with microplastics obtained from products containing these additives or in environmental contexts containing these microplastics. Examples are hotspots of these microplastics, such as those found near the intensive use of spray paint, like construction sites, car workshops, and shipyards, or agricultural areas with the usage of biodegradable mulching films. The main advantages of this proposal are 1) the replacement of a multi-step protocol consisting of digestion of organic matter ’ separation by density ’ decantation or centrifugation ’ vacuum filtration ’ optical microscopy by a single-step technique of X-ray fluorescence spectroscopy; 2) determining the spatial distribution of microplastics in contaminated tissues and organs using the X-ray computed microtomography technique; 3) transposing the technique developed in the laboratory for the usage monitoring ecosystems contaminated with the type of microplastic studied in this project. (AU)