Detection and quantification of microplastics in various types of human tumor tissues.
Level 4 - case-series / case-control
Cross-sectional analysis / case series of human tumor tissue specimens
PubMed 39083862 · doi:10.1016/j.ecoenv.2024.116818
What was done
Researchers collected 61 human tumor samples across multiple cancer types (lung, gastric, colorectal, cervical, pancreatic, and esophageal) to assess the presence and quantity of microplastics. Samples were qualitatively and quantitatively analyzed using pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). In pancreatic tumor samples, researchers also examined characteristics of the tumor immune microenvironment.
What was found
Microplastics were detected in 26 of 61 tumor samples (42.6%). Three polymer types were identified: polystyrene, polyvinyl chloride, and polyethylene. Reported detection rates were 80% in lung tumors, 70% in pancreatic tumors (18.4–427.1 ng/g), 50% in colorectal tumors, 40% in gastric tumors, 17% in cervical tumors (concentrations across lung, gastric, colorectal, and cervical tumors ranged from 7.1 to 545.9 ng/g), and 0% in esophageal tumors. In pancreatic cancer, microplastic infiltration correlated with decreased CD8+ T cells, natural killer cells, and dendritic cells, alongside increased neutrophil infiltration.
Why it matters
This study provides observational evidence that environmental microplastics can deposit within various human tumor tissues. It also identifies a potential correlation between microplastic presence and an altered, immunosuppressive tumor microenvironment in pancreatic cancer.
Limits
The total sample size is small (61 tumor samples) and split across six different cancer types, limiting statistical power. The cross-sectional tissue design cannot establish causation between microplastics and immune alterations or tumorigenesis. The abstract does not mention matched adjacent normal tissue controls or patient exposure data.
Cited by
- supports Microplastic particles have been detected inside human lung cancer tumor tissue samples.