Human Exposure to Microplastics and Its Associated Health Risks

Area of Science:

• Environmental Science
• Toxicology
• Human Health Risk Assessment

Background:

• Microplastics (MPs) are ubiquitous environmental pollutants with largely unknown human health implications.
• Exposure routes include ingestion, inhalation, and dermal penetration, with evidence of MPs in human excrement, biofluids, and tissues.
• Current toxicological data primarily relies on animal models and cell studies.

Purpose of the Study:

• To review the current understanding of microplastic risks to human health.
• To highlight key findings on MP presence in human samples and cellular toxicity.
• To identify knowledge gaps in assessing MP risks under environmentally realistic conditions.

Main Methods:

• Literature review of toxicological studies on microplastics.
• Analysis of evidence for microplastic presence in human biological samples.
• Evaluation of cellular-level impacts and potential for contaminant co-transport.

Main Results:

• Microplastics detected in human excrement, biofluids, and tissues.
• Identified potential impacts on energy homeostasis, gut microbiota, and nervous, immune, and reproductive systems.
• Observed cellular toxicity affecting lysosomes, mitochondria, endoplasmic reticulum, and the nucleus.
• Recognized MPs as vectors magnifying the toxicity of co-contaminants.

Conclusions:

• Microplastics pose potential risks to human health, affecting multiple physiological systems and cellular structures.
• Further research under environmentally realistic conditions is crucial for accurate risk prediction.
• Dermal penetration requires further investigation as a significant exposure route.