Australian scientists have found that paper cups with biodegradable coating release significantly more nanoplastics into hot drinks than traditional ones, reports infohub.kz.
Researchers at the University of Queensland compared disposable cups for hot beverages: those with a protective layer of polylactic acid (PLA), derived from corn or sugarcane, and those with a conventional polyethylene coating. The results showed that eco-friendly alternatives may be less safe for consumers.
In experiments, cups with PLA coating released about twelve times more plastic mass when in contact with hot water compared to polyethylene ones. The eco-friendly cups released approximately 4.3 million nanoparticles per milliliter of liquid, while traditional cups released 2.7 million particles. The size of the released particles is comparable to that of large viruses and small bacteria.
The researchers emphasize that these findings do not indicate an immediate health risk from polylactic acid. However, its effects on the body remain poorly understood, and chemicals from plastic are not intended for consumption. The authors call on manufacturers to improve technologies and on regulators to mandate testing of materials for microplastic release.