Plastic waste pollution is one of the world’s biggest problems today. The amount of plastic in the environment continues to increase and human exposure to microplastic has become a reality. The term microplastic is mainly used to define synthetic material with high polymer content that can have a size range from 0.1 to 5000 μm. This contaminant is ubiquitous in the environment, the air we breathe and the food we eat.
Ingestion of contaminated food
It is believed that the most common route of exposure to microplastics is through the gastrointestinal tract. Its ingestion occurs involuntarily. It is estimated that people worldwide can consume 0.1–5 g of these particles per week. After oral exposure, hazardous substances (e.g., polycyclic aromatic hydrocarbon – PAH and polychlorinated biphenyl – PCB) may appear in the gastrointestinal tract. Some are excreted from the human body by feces. Ethylene teephthalate was the most frequently identified in these samples. Fecal examinations confirmed that the concentration of microplastics in infant feces was 10 times higher than in adult samples. Particularly worrisome is the information that microplastic was also detected in meconium samples. As discovered in human feces, it is believed to directly affect the microbiota, consequently affecting health.
Food with microplastics
Microplastics pose a potential threat to human health due to their widespread presence in the food we eat. The most common plastic particles found in food are blue and fiber-shaped. Sources of microplastics for humans can be drinks and foods such as water, tea, beer, wine, energy drinks, soft drinks, salt, sugar, honey, animal products including fish, seafood, milk, poultry meat and plants, including fruits and vegetables.
Microplastic can cause acute and chronic toxicity. Toxic effects include: reproductive and locomotor toxicity, neurotoxicity, immunotoxicity, genotoxicity and cytotoxicity. In addition, the increase in antioxidant defense after exposure indicates that there is induction to oxidative stress. However, the health effects depend on their location in the body: microplastics were found on the skin, hair, saliva and fecal samples.
Microplastic is an omnipresent contaminant found in air, water and soil. In this context, it is believed that the most common route of exposure is through the gastrointestinal tract. Therefore, andposes a significant threat to human health due to its widespread occurrence in food. This occurs as it can accumulate in the body, induce inflammation and have adverse effects on the immune, endocrine, reproductive and digestive systems. Thus, its exposure is associated with a risk of oxidative stress, changes in cell division and viability, DNA damage, immune responses, metabolic disorders, intestinal dysbiosis, increased risk of cancer, respiratory and neurodegenerative diseases. In addition, it is assumed that plastic particles may be one of the causes of autism spectrum disorder.
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– Kadac-Czapska K, Knez E, Grembecka M. Food and human safety: the impact of microplastics [published online ahead of print, 2022 Oct 17]. Crit Rev Nutr Sci Food
. 2022;1-20. Doi:10.1080/10408398.2022.2132212