A new examination of common protein sources shows that microplastics appear in nearly every category tested. Researchers found the particles in 88 percent of samples across 16 different products bought from stores in the Portland, Oregon, area and from local fishing boats. The contamination levels varied sharply depending on how much processing the food had undergone.
Processed Items Show Highest Counts
Breaded shrimp recorded the greatest average load at 370 microplastic particles per serving. Plant-based nuggets followed with 73 particles, while conventional chicken nuggets averaged 62. These figures stood well above those for minimally processed options such as plain chicken breast, which contained just two particles per serving on average.
The pattern pointed to processing steps as a key factor. Highly processed items consistently carried more particles per gram than their less-treated counterparts. Fresh-caught seafood still contained some microplastics, however, showing that contamination can begin before products reach any store shelf.
Brand and Store Choices Offer Little Relief
Researchers tested products from multiple brands and both conventional supermarkets and natural-food stores. They found no meaningful difference in microplastic levels tied to either factor. The same held true when comparing land-based proteins with those from the ocean.
Lead author Madeleine Milne noted that it remains difficult to recommend specific swaps to reduce exposure. The team combined its measurements with national dietary data and estimated that the average U.S. adult takes in roughly 11,000 microplastic particles each year from the proteins studied. Upper-end estimates reached as high as 3.8 million particles annually for heavy consumers of the most contaminated items.
Broader Context and Remaining Questions
Microplastics have already been detected in human blood, organs, and tissues, though scientists continue to study possible health effects. The current work adds detail on dietary sources without claiming direct links to illness. Co-author Britta Baechler described the findings as a reminder of how widespread plastic pollution has become.
Further research is needed to trace exact entry points during production and to clarify long-term risks. In the meantime, the results underscore that microplastics are difficult to avoid entirely through protein choices alone.
| Protein Item | Average Particles per Serving |
|---|---|
| Breaded shrimp | 370 |
| Plant-based nuggets | 73 |
| Chicken nuggets | 62 |
The study, published in Environmental Pollution, examined 111 samples in total and confirmed microplastics in every one of the 16 protein types. ([1])
AI Disclaimer: This article was created with the assistance of AI tools and reviewed by a human editor.