Silicone is a synthetic polymer, but it is chemically different from conventional thermoplastics such as polypropylene and polyethylene. Silicone rubber can release microscopic polymer-containing particles under severe conditions, but normal-use evidence for spatulas, spoons, bags, lids, and seals is still too limited to quantify how much they release or how they compare with representative plastic products.
The bottom line
Silicone should not automatically be described as microplastic-free. Researchers have identified silicone-derived particles after repeated steam disinfection of silicone-rubber baby-bottle teats.
That study does not show that an ordinary silicone spatula or refrigerated storage bag releases the same amount. No robust study was located that tested representative silicone and conventional-plastic utensils or storage products side by side under the same normal-use conditions.
Silicone can still be a reasonable lower-microplastic choice when flexibility is needed. That is a qualified material judgment, not a measured percentage reduction or a promise of zero shedding.
Is silicone a type of plastic?
Silicone is a family of manufactured materials built mainly around repeating silicon-oxygen bonds. Flexible kitchen silicone is usually a cross-linked elastomer, meaning its polymer chains are connected into a rubber-like network.
Many familiar conventional plastics are thermoplastics. Polypropylene and polyethylene, for example, can be melted and reshaped because their chains are not joined in the same way.
Silicone's chemistry and behavior are different, but both groups are manufactured polymer materials. That is why the statements “silicone is plastic” and “silicone is not plastic” can each leave out useful context.
For a kitchen decision, it is more useful to ask what can leave the finished product, under which conditions, and how closely those conditions match real use.
Do silicone particles count as microplastics?
Definitions are not completely uniform. Some scientific and regulatory descriptions focus on solid, synthetic polymer-containing particles and may include silicone fragments when they meet the relevant criteria. Other discussions use “microplastics” mainly for particles from familiar carbon-based plastics.
The silicone study cited below called the material micro(nano)plastics. PFK will not use a terminology dispute to imply that silicone is particle-free. We will name the measured material, product, size range, and treatment instead.
A microscopic piece of silicone rubber is also different from an individual siloxane molecule migrating into a liquid. Particle release and chemical migration require different methods and should be evaluated separately.
What has been measured?
Researchers studied silicone-rubber baby-bottle teats exposed to repeated steam disinfection. Using optical photothermal infrared microspectroscopy, they identified flake-like and oil-film-shaped particles ranging from approximately 0.6 to 332 micrometers. Their analysis linked the material to degradation of the PDMS silicone elastomer and another polymer used in the product.
This shows that cross-linked silicone rubber can release microscopic polymer-containing material under repeated severe moist heat. It does not establish release from ordinary spatulas, spoons, bags, lids, or gaskets. It also does not establish a category-wide household exposure level or a demonstrated health outcome.
Baby-bottle steam disinfection is a demanding and specific use case. Its particle counts and modeled infant-intake estimates should not be transferred to normal kitchen products.
How does that compare with conventional plastic?
A 2023 study tested selected polypropylene food containers and polyethylene-based reusable pouches using water and 3% acetic acid. Researchers detected microplastics and nanoplastics after microwave heating and after prolonged room-temperature and refrigerated storage. Microwave heating produced the highest release under that study's conditions.
This is direct evidence that some conventional-plastic food-storage products can release particles during relevant categories of use. It does not mean every plastic item releases the same amount, and its counts cannot be transferred to an untested container or pouch.
Does silicone release fewer particles?
We do not yet have the head-to-head evidence needed for a numerical answer. A fair comparison would test representative silicone and conventional-plastic products using the same foods or simulants, temperatures, washing cycles, wear routines, particle-size ranges, and contamination controls.
Without that evidence, it would be too strong to claim that silicone always sheds less or reduces microplastic consumption by a set percentage.
The practical case for silicone rests on its different cross-linked structure, its usefulness in flexible applications, and direct evidence that some conventional-plastic foodware releases particles. The uncertainty is that ordinary silicone utensils and storage products have not been measured well enough.
Where is more evidence needed?
The largest gaps involve spatulas, spoons, reusable bags, stretch lids, seals, gaskets, and products repeatedly washed and used over months or years.
Studies should test finished products intact when possible and identify which material produced each particle. That matters because a product sold as silicone may also contain a core, pigment, seam, adhesive, or another polymer.
PFK's conclusion
The evidence supports restraint in both directions. Silicone is not proven particle-free, but severe treatment of baby-bottle teats does not quantify release from ordinary kitchenware.
Well-documented silicone can be a reasonable lower-microplastic choice when a flexible product is needed. That conclusion should remain qualified until representative normal-use comparisons are available.
PFK may offer silicone products, but none of the studies cited here tested a current or future PFK item. A food-contact certificate or curing description is not proof of zero shedding.
For chemical migration rather than solid particles, read Does Silicone Leach BPA or Other Chemicals Into Food?. For practical maintenance, read How to Use, Clean, and Replace Silicone Kitchenware.
Research reviewed July 27, 2026. This article is educational and is not medical advice.
Sources
- Su Y, Hu X, Tang H, et al. “Steam disinfection releases micro(nano)plastics from silicone-rubber baby teats as examined by optical photothermal infrared microspectroscopy.” Nature Nanotechnology. 2022;17:76-85. doi:10.1038/s41565-021-00998-x
- Hussain KA, Romanova S, Okur I, et al. “Assessing the Release of Microplastics and Nanoplastics from Plastic Containers and Reusable Food Pouches: Implications for Human Health.” Environmental Science & Technology. 2023;57(26):9782-9792. doi:10.1021/acs.est.3c01942
- Liu YQ, Wang ZW, Hu CY. “Progress in research on the safety of silicone rubber products in food processing.” Comprehensive Reviews in Food Science and Food Safety. 2023;22(4):2887-2909. doi:10.1111/1541-4337.13165