Microplastics Detected in Human Tissues, Yet Health Risks Remain Unclear

Over recent years, scientists have increasingly identified microplastic particles—smaller than five millimetres—in human biological samples, including blood, various organs and even the olfactory region of the brain. These particles enter the body mainly via contaminated food, drinking water and airborne dust, and may also reach the central nervous system through the nasal passage. Studies from 2024 reported synthetic polymers in the brains of eight of fifteen deceased individuals and in cerebrospinal fluid of 28 subjects, though no significant link to inflammatory markers was observed.

A 2026 systematic review of 25 human investigations noted correlations with inflammatory markers, cardiovascular outcomes, reduced sperm quality, gut disturbances and respiratory inflammation, but methodological differences prevent firm causal conclusions. Researchers caution that microplastics could trigger oxidative stress, hormonal disruption and cellular damage, especially if they breach the blood-brain barrier, yet definitive clinical evidence is lacking. Meanwhile, experts advise reducing exposure by limiting single-use plastics, improving ventilation and choosing less plastic-intensive products.