The pervasive presence of microplastics (MPs) and nanoplastics (NPs) in the environment has emerged as a growing concern for human health. Derived from the breakdown of larger plastics and introduced through various industrial applications, these microscopic particles infiltrate the air we breathe, the water we drink, and the food we consume. While their environmental impact has been widely studied, their potential effects on human health remain inadequately understood. The article, “The Potential Impacts of Micro- and Nanoplastics on Various Organ Systems in Humans,” published in eBioMedicine (2024), provides a comprehensive review of the ways in which MPs and NPs may affect human organ systems.

The authors, Nurshad Ali et al., delve into the exposure pathways, organ-specific effects, and toxicity mechanisms of MPs and NPs, highlighting the potential risks posed to respiratory, gastrointestinal, cardiovascular, nervous, immune, and endocrine systems, among others. By synthesizing findings from cellular and animal studies, the article sheds light on the biological disruptions caused by these particles and the gaps in current research. This review critically evaluates the article’s findings, its contributions to the field, and its limitations, emphasizing the importance of further research to address this emerging public health concern.

Overview of the Article

The authors explore three key areas: pathways of exposure, organ system-specific health effects, and mechanisms of toxicity. Their findings are based on a combination of in vitro and in vivo studies, offering insights into how MPs and NPs interact with human physiology.

1. Exposure Pathways: The article details how humans encounter MPs and NPs through:
   • Ingestion: Found in food, water, and packaging materials, MPs are confirmed in human stool, highlighting their dietary presence.
   • Inhalation: Airborne MPs from sources such as synthetic textiles and construction materials are inhaled, potentially causing respiratory issues.
   • Dermal Contact: Although less significant, MPs can penetrate the skin via products like cosmetics.

• Health Impacts on Organ Systems: The review systematically examines the effects of MPs and NPs on various organ systems:
  • Respiratory System: MPs cause inflammation, oxidative stress, and tissue damage in the lungs.
  • Gastrointestinal System: They disrupt gut microbiota and intestinal barriers, leading to inflammation.
  • Cardiovascular System: MPs promote oxidative stress, impair blood clotting, and may damage heart tissues.
  • Liver and Kidneys: MPs accumulate in these organs, leading to oxidative stress, inflammation, and potential fibrosis.
  • Reproductive and Developmental Systems: Hormonal disruptions and tissue damage compromise fertility and embryonic development.
  • Nervous System: MPs induce neurotoxicity and disrupt neurotransmitter activity, with potential long-term effects on brain health.
  • Immune System: MPs activate inflammatory responses, though their impact on adaptive immunity remains unclear.
  • Endocrine and Muscular Systems: Endocrine-disrupting chemicals in MPs disturb hormonal balance, while MPs impair muscle regeneration.
• Mechanisms of Toxicity: The article highlights how MPs and NPs cause cellular damage through oxidative stress, mitochondrial dysfunction, DNA damage, and lysosomal destabilization. The formation of protein coronas on MPs is identified as a factor influencing their interactions with human cells and tissues.
• Knowledge Gaps and Recommendations: The authors emphasize the need for:
  • Standardized methods to detect and study MPs and NPs.
  • Research on diverse plastic types and environmentally relevant exposures.
  • Long-term studies on dose-dependent effects and individual susceptibilities.

The article excels in synthesizing data from diverse studies to provide a holistic understanding of MNP exposure and its health implications. Its detailed exploration of toxicity mechanisms and systemic effects offers a robust framework for further investigation. However, the article focuses predominantly on pristine polystyrene MPs, which do not represent the diversity of real-world plastics. Additionally, the reliance on animal and cellular studies limits the applicability of findings to humans. It is a critical contribution to the understanding of micro- and nanoplastics’ effects on human health. By addressing exposure pathways, organ-specific impacts, and toxicity mechanisms, it provides valuable insights and underscores the urgent need for standardized research methodologies. The authors’ recommendations pave the way for addressing the knowledge gaps and mitigating the health risks posed by MPs and NPs. For researchers, healthcare professionals, and policymakers, this article serves as a call to action

find the original article on https://doi.org/10.1016/j.ebiom.2023.104901

Disclosure: parts of this review was written with the help of AI software(s)