High levels of microparticles release from biodegradable polylactic acid paper cups compared with polyethylene-lined cups
Level 5 - mechanism / opinion, no new human data
Bench experimental study measuring material particle release; level 5 by design analogy.
OpenAlex W4377115462 · doi:10.1016/j.cej.2023.143620
What was done
Researchers measured the release of microparticles from eight types of single-use paper cups lined with either biodegradable polylactic acid (PLA) or conventional polyethylene (PE) films under typical hot-beverage preparation conditions, capturing particles larger than 0.8 μm.
What was found
PLA-lined cups released 4.2 times more total particles than PE-lined cups (180,000 ± 31,000 vs 43,000 ± 10,000 particles/L). Microplastic release specifically was 3.6 times higher from PLA cups than PE cups (22,000 ± 6,000 vs an implied ~6,100 particles/L). PLA cups also released 38,000 ± 31,000 cellulose microfibres/L, while PE-lined cups released no detectable cellulose fibres.
Why it matters
Biodegradable plastics like PLA are widely used as eco-friendly alternatives to conventional plastics, but they may shed substantially more microparticles and microplastics into hot drinks during standard consumer use.
Limits
The study tested only eight cup varieties under simulated conditions. Total particle shedding was likely underestimated because particles smaller than 0.8 μm and certain obscured or aggregated particles were excluded. In vivo human exposure and biological toxicity were not assessed.
Cited by
- supports Disposable paper cups are lined with plastic that releases microplastics when heated.