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

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.

Detection of Microplastic in Human Placenta and Meconium in a Clinical Setting.

Environmental pollution with microplastics (MPs) is a major and worldwide concern. Involuntary exposure to MPs by ingestion or inhalation is unavoidable. The effects on human health are still under debate, while in animals, cellular MP translocation and subsequent deleterious effects were shown. First reports indicate a potential intrauterine exposure with MPs, yet readouts are prone to contamination. METHOD: To establish a thorough protocol for the detection of MPs in human placenta and fetal meconium in a real-life clinical setting, a pilot study was set up to screen for MPs > 50 µm in placental tissue and meconium sampled during two cesarean sections for breech deliveries. After chemical digestion of non-plastic material, Fourier-transform infrared (FTIR) microspectroscopy was used to analyze the presence of 10 common types of microplastic in placenta and stool samples. RESULTS: Human placenta and meconium samples were screened positive for polyethylene, polypropylene, polystyrene, and polyurethane, of which only the latter one was also detected as airborne fallout in the operating room-thus representing potential contamination. CONCLUSION: We found MPs > 50 µm in placenta and meconium acquired from cesarean delivery. Critical evaluation of potential contamination sources is pivotal and may guide future clinical studies to improve the correct detection of MPs in organ tissue. Studies investigating nano-sized plastics in human tissue are warranted.

The occurrence and dietary intake related to the presence of microplastics in drinking water in Saudi Arabia.

The implications and health effects of microplastics (MPs) ingestion are still unclear, yet researchers and organizations around the world are increasingly examining the levels of microplastics and nanoplastics in the environment. This study investigated the presence and the quantity of microplastics in bottled and tap water from five regions in Saudi Arabia and estimated the dietary intake of microplastics. Thirty samples of drinking water were collected from the retail markets in Saudi Arabia. The samples included plastic bottled drinking water, 2 glass bottles, and 2 samples of tap water to represent ground water and desalinated seawater. Sample preparation in the laboratory involved a vacuum-assisted filtration with an inorganic filter membrane (0.2-µm pore size). Identification and classification of microplastics particles using Fourier-transform infrared microspectroscopy (FTIR microspectroscopy). The particle size range screened for in this study was 25-500 µm. Microplastics were identified in 17 out of 30 samples. The average of the detected microplastic particles was 1.9 pcs/L (lower bound estimate, LB) and 4.7 pcs/L (upper bound estimate, UB), respectively. The most frequently identified plastic type was polyethylene (PE), followed by polystyrene (PS), and polyethylene terephthalate (PET). Given an average recommended water intake of 3.7 and 2.7 L per day for men and women, respectively, the corresponding daily exposure to microplastics would result in 0.1-0.2 pcs/kg bw. The estimate for high water consumers increases to a daily exposure of 1.7-1.9 pcs/kg bw based on the recommended intake for water in hot weather by the WHO. From these results, we conclude that the level of dietary intake of microplastics from drinking water in Saudi Arabia is low, and according to current state of knowledge, microplastics from drinking water do not pose any concern to the consumers in Saudi Arabia.