Microplastics and Skin Absorption: What Can Actually Cross the Skin?

Last updated: May 25, 2026

Why intact skin blocks most particles

The stratum corneum, the outermost layer of dead skin cells held together by lipids, is an effective barrier against particles larger than about 1 micrometre. Most microplastic particles in the environment are 5–500 µm, well outside the skin's permeability range. Laboratory studies on isolated skin samples consistently show negligible particle penetration at typical environmental exposures.

But the chemicals absorb readily

Plastic-associated chemicals are small enough to cross the skin barrier, many are deliberately formulated to penetrate (in pharmaceutical and cosmetic contexts). Several human-relevant examples:

Three skin-routes worth knowing

1. Thermal receipts. Hormann et al. (2014, PLOS One) showed handling a thermal receipt for 5 seconds and then handling food (e.g. at a checkout) increased BPA exposure measurably. People handling receipts daily as part of their job (cashiers, gas station attendants) have substantially higher urinary BPA than average.
2. Cosmetics and lotions with synthetic polymers.Anything you apply to skin and leave on (moisturisers, sunscreens, lip products, deodorants) that lists PEG, polyethylene, acrylates copolymer, carbomer, or polyquaternium-(any number) is depositing polymer onto your skin. Particles may not cross, but the chemistry does.
3. Synthetic textiles. Polyester, nylon, and acrylic clothing release brominated flame retardants and plasticisers that absorb through skin during contact, especially during sweat-generating activities.

Practical skin-protective changes

1. Decline thermal receipts at gas stations and retail checkouts when possible. Ask for email receipts.
2. Wash hands after handling receipts before eating. Especially important for daily cashier-like exposure.
3. Read leave-on cosmetic labels for PEG, polyethylene, acrylates copolymer, carbomer. Brands certified by EWG VERIFIED, MADE SAFE, or COSMOS Organic typically avoid synthetic polymers.
4. Switch to natural-fibre clothing, cotton, linen, wool, silk, hemp, Tencel. Especially underwear and sleepwear (8+ hours of contact daily).
5. Avoid “fragrance” in unspecified products.Often a phthalate-carrying mixture.
6. Choose mineral sunscreens (zinc oxide, titanium dioxide) over chemical sunscreens that may contain synthetic polymers and absorb-able UV filters.
7. Limit hot-tub and pool exposure with synthetic swimsuits, heat + chlorine + sweat increases textile chemical migration into skin.

See related: microplastics in cosmetics, microplastics in toothpaste and personal care, and best polymer-free toothpaste.