Microplastic Contamination in Tea

Microplastic (MP) contamination in tea has emerged as a significant concern for China’s tea industry, the world’s largest producer and consumer of tea. This chapter examines the pervasive infiltration of MPs throughout the tea production chain—from cultivation to consumption—highlighting key sources of contamination, associated health risks, and potential mitigation strategies. MPs enter tea ecosystems through agricultural plastic films, atmospheric deposition, and the use of organic fertilizers, with tea garden soils containing up to 3472 particles/kg. Mechanical processing stages, particularly rolling and kneading, exacerbate contamination, releasing 2266 ± 1206 particles/kg. Plastic tea bags, often marketed as “premium,” release 11.6 billion MPs and 3.1 billion nanoplastics (NPs)/bag when brewed at 95°C, posing ingestion risks linked to inflammation, liver damage, and endocrine disruption. China’s tea consumption habits—high-temperature brewing and prolonged steeping—amplify exposure, though bulk tea presents lower risks than plastic tea bags. Mitigation strategies include agricultural reforms (such as biodegradable mulch, buffer zones near roads, and optimized fertilizers); industrial adjustments (stainless steel equipment, reduced processing temperatures, and non-plastic packaging); and consumer practices (pre-rinsing tea bags, opting for loose-leaf tea, and shorter brewing times). Despite current exposure levels being classified as “extremely low,” long-term bioaccumulation risks and synergistic effects with adsorbed pollutants (e.g., heavy metals) warrant urgent policy updates and interdisciplinary research. The chapter advocates for standardized regulations, green packaging innovations, and consumer awareness to safeguard China’s tea industry and public health.