Your morning takeaway coffee may contain millions of nanoparticles

The study, published in ACS Food Science & Technology, examined cups lined with fossil-based polyethylene (PE) and biodegradable polylactic acid (PLA). Researchers found that PLA-lined cups released approximately 4.3 million nanoparticles per millilitre—a 12-fold increase compared to the 2.7 million particles detected in PE-lined versions. These nanoparticles measure roughly a thousand times thinner than a human hair, making them easily ingestible.

Dr. Elvis Okoffo, who led the research, noted that while these findings highlight a significant source of human exposure, they do not necessarily mean current materials are inherently unsafe. Instead, the data points to a gap in how food-storage products are evaluated. Okoffo is calling for regulators to incorporate particle-release testing into safety assessments for hot-beverage containers and is urging manufacturers to improve cup lining designs to minimize shedding. Until such standards are established, the team suggests that better product labeling could help consumers make more informed choices about their daily coffee habits.