Assessment of microplastics in human stool: A pilot study investigating the potential impact of diet-associated scenarios on oral microplastics exposure

• Published in: The Science of the total environment 2024-11, Vol.951, p.175825, Article 175825
• Main Authors: Hartmann, Christina, Lomako, Ievgeniia, Schachner, Carla, El Said, Evelin, Abert, Julia, Satrapa, Vito, Kaiser, Andreas-Marius, Walch, Helene, Köppel, Sebastian
• Format: Article
• Language: English
• Subjects: Diet; FTIR; Human feces; Intervention study; Plastic
• ISSN: 0048-9697; 1879-1026; 1879-1026
• DOI: 10.1016/j.scitotenv.2024.175825

As emerging contaminants microplastic particles have become of particular relevance as they are widely present in the environment and of potential concern to human health. Humans are exposed through different routes, with oral intake and inhalation being the most significant. Dietary intake substantially contributes to oral exposure, although data is still lacking. This first-of-its-kind pilot study investigates the influence of different plastic use and food consumption scenarios (normal, low, high) on microplastic content in stool reflecting oral intake by performing an intervention study with fifteen volunteers. Stool samples were analyzed for ten different plastic types in three size fractions including 5–50 μm (qualitative), 50–500 μm and 500–5000 μm (quantitative). In all samples, microplastic particles were detected with median concentrations up to 3.5 particles/g stool in the size fraction 50–500 μm. Polyethylene was the most frequently detected polymer type. The different scenarios did not result in a consistent pattern of microplastics, however, the use of plastics for food packaging and preparation, and the consumption of highly processed food were statistically significantly associated with microplastics content in stool. These results provide initial findings that contribute to filling current knowledge gaps and pave the way for further research. [Display omitted] •Diet influences human microplastics exposure.•Degree of food processing contributes to microplastic intake.•Up to nine different plastic types were detected in stool samples.