We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Tea bags as hidden source of micro- and nanoplastics: a systematic review for food safety.
AI summary Read the abstract
Researchers systematically reviewed 19 studies on microplastic and nanoplastic release from tea bags during brewing, finding that plastic-containing bags—particularly polypropylene and nylon—release billions of particles per bag at typical brewing temperatures, with release rates shaped by material type, water temperature, brew time, and agitation, though standardized detection methods remain lacking.
BACKGROUND: The release of micro- and nanoplastics (MNPs) from tea bags during brewing is a significant, recently identified source of potential human exposure. This systematic review collected global research published up to the end of 2025, indexed in PubMed, ScienceDirect, Web of Science, and Scopus, adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Study objective was to systematically detect, quantify, and characterize MNPs released from various tea bag materials. The review focused exclusively on studies that directly measured MNPs release under brewing conditions. METHODOLOGY: A systematic literature search was conducted through specified databases. Inclusion criteria focused on studies quantifying MNPs release (by count or mass) from tea bags during brewing, irrespective of water temperature or time, but studies relying on in-vitro or in-vivo models, review/conference/retracted papers, or books/chapters were excluded. Data extraction included MNPs type, quantity, size range, tea bag material, brewing conditions, and detection methods. MAIN FINDINGS: Our systematic search identified 19 studies meeting the inclusion criteria. A significant finding is the substantial release of MNPs, often in billions of particles per bag, from plastic-containing tea bags (e.g., non-woven polypropylene, nylon) brewed in hot water (typically ≥95 °C). Released particles predominantly ranged from nano-to micrometer sizes. Release quantities were found to be influenced by tea bag material, water temperature, brewing duration, and mechanical agitation. While some materials like paper or woven nylon showed lower release rates, even composite or supposedly "eco-friendly" bags contributed measurable MNPs release. LIMITATIONS AND GAPS: Despite the direct evidence of MNPs release, some research gaps persist. Crucially, standardized methodologies for detection and quantification of MNPs, and human health risk assessment are lacking, obstructing comparability across studies. Furthermore, while our review focused on MNPs release, the in-vivo or in-vitro evidence regarding the biological implications remains largely outside the scope of this specific systematic review's direct findings, necessitating separate, targeted investigations. Current global exposure estimates are preliminary due to these methodological and data limitations. CONCLUSION: This systematic review confirms that tea bags, particularly those containing plastics, are a notable source of MNPs release into beverages and environment. While considerable quantities of MNPs are released, future systematic efforts should highlight developing and implementing standardized detection methodologies to improve the reliability of findings, alongside focused investigations into the biological and toxicological effects of MNPs and human health risk assessment. Furthermore, exploring and promoting innovative solutions, such as the use of biodegradable materials with minimal or without MNPs releasing and alternative brewing technologies, is crucial for mitigating MNPs contamination from tea consumption.
More Papers Like This
Determination of the microplastic particle release by tea bags during brewing
AI summary Read the abstract
Researchers measured the release of microplastic particles from tea bags during brewing, finding that plastic particles leach into the hot beverage. This study highlights an often-overlooked source of microplastic ingestion through everyday food and drink preparation.
Microplastics and nanoplastics in tea: Sources, characteristics and potential impacts
AI summary Read the abstract
This review looks at how microplastics and nanoplastics end up in tea, with plastic teabags being the biggest culprit, releasing over a billion tiny particles per bag when steeped in hot water. Even biodegradable and composite tea bags release significant amounts of plastic particles, raising health concerns given that tea is one of the most widely consumed beverages in the world.
Investigating the release of microplastics from tea bags into tea drinks and human exposure assessment
AI summary Read the abstract
Researchers tested tea bags from five brands in Iran and found that every brand released microplastics into the tea, with an average of over 500,000 particles per bag. The most common plastics were cellulose acetate and nylon fibers, mostly in the 10-50 micrometer size range. Based on typical tea consumption, children and adults could be ingesting thousands of microplastic particles per kilogram of body weight daily just from drinking tea.
Determination of the Microplastic Particle Release by Tea Bags During Brewing
AI summary Read the abstract
This study developed a method for detecting and quantifying microscopic plastic particles released from commercial tea bags during brewing. The research found that steeping tea bags releases substantial numbers of microplastic particles into the beverage, raising concerns about microplastic exposure through a widely consumed drink.
Health risks posed by microplastics in tea bags: microplastic pollution – a truly global problem
AI summary Read the abstract
This study examines the health risks associated with microplastics released from tea bags during the brewing process. Researchers highlight that commonly used tea bag materials like polypropylene and nylon can release significant numbers of microplastic particles and potentially harmful chemicals when exposed to high temperatures. The study suggests that microplastic contamination in tea bags, along with associated compounds like heavy metals and fluorine, warrants further investigation to protect consumer health.
Research digests by email
When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.