Abstract
The human body is exposed to the ingestion of microplastics that are often contaminated with other substances, which can be released into our body. In this work, a dynamic in-vitro simulator of the gastrointestinal tract based on a membrane reactor has been used for the first time to study the release, bioaccessibility, and bioavailability of chromium (Cr) and lead (Pb) from polyethylene and polypropylene microplastics previously contaminated in the laboratory. The results showed that 23.11% of the initial Cr and 23.17% of the initial Pb present in microplastics were able to cross the tubular membrane, simulating the intestinal absorption phase. The pH evolution during the gastric phase and the duodenal phase, the interaction mechanisms with physiological fluids, and the properties of the polymers, such as specific surface, porosity, and/or surface degradation, affected the kinetics of release from the microplastics and the behavior of both heavy metals. Cr was released very early in the gastric phase, but also began simultaneously to precipitate quite fast, while Pb was released slower and in less quantity than Cr, and did not precipitate until the beginning of the duodenal phase. This study shows, for the first time, how useful the dynamic gastrointestinal simulator is to study the behavior of microplastics and some problematic heavy metals along the human gastrointestinal tract, and can serve as a reference for future studies focused on the effects of these substances in the human body.
Highlights
Concern for microplastics and their environmental impact has been growing in recent years
The microplastics used were analyzed after the in-vitro tests using a digital microscope in order to detect possible surface degradation or deformation, as well as color changes produced after its passage through the different simulated gastrointestinal conditions (Figure 2)
The objective of this research was to study the bioaccessibility of two heavy metals (Cr and Pb) contained in microplastics in the human body by using a dynamic gastrointestinal simulator
Summary
Concern for microplastics and their environmental impact has been growing in recent years. Microplastics are present in all aquatic environments, including oceans, seas, rivers, and lakes of the entire planet, in addition to being deposited and accumulated in the sand of beaches, estuaries, river basins, and all kinds of landfills [4,5]. Some of the most common pollutants in microplastics are metals and heavy metals, such as chromium, iron, lead, or titanium [11,12,13] These metals can be indirectly adsorbed onto the microplastics in aquatic environments or directly added to plastics as metal additives to enhance their properties during the manufacturing process. This author demonstrated, through the simulation of an avian gizzard, that some metals, such as Mn, Zn, Fe, or Pb, adhered to the surfaces of the pellets, could be released, and could become bioaccessible to the birds’ gastrointestinal tracts as well
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
