Polycyclic aromatic hydrocarbons in teas using QuEChERS and HPLC-FLD

Area of Science:

• Food Chemistry
• Analytical Chemistry
• Environmental Health

Background:

• Polycyclic aromatic hydrocarbons (PAHs) are recognized as carcinogenic and genotoxic food contaminants.
• Tea processing, particularly drying, can lead to PAH contamination.
• Assessing PAH levels in various teas is crucial for public health.

Purpose of the Study:

• To validate a QuEChERS and HPLC-FLD method for determining PAH4 in teas.
• To quantify PAH contamination levels in 10 different Brazilian tea types.
• To evaluate the potential health risks associated with PAH intake from tea consumption.

Main Methods:

• Method validation using QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) extraction.
• High-Performance Liquid Chromatography with a Flame Ionization Detector (HPLC-FLD) for PAH4 analysis.
• Analysis of 10 distinct tea varieties sourced from Brazil.

Main Results:

• Method validation demonstrated good recoveries (54–99%) and precision (RSD 1–21%).
• Detection and quantification limits ranged from 0.03–0.3 µg/kg and 0.1–0.5 µg/kg, respectively.
• Mate tea exhibited the highest PAH4 levels (194–1795 µg/kg), followed by black, white, and green teas. Strawberry, lemongrass, peppermint, and boldo teas had the lowest levels.

Conclusions:

• The validated analytical method is suitable for determining PAH4 in teas.
• Significant PAH contamination was found in several popular tea types in Brazil, with mate tea being the most affected.
• PAH intake from tea infusions is likely minimal, suggesting low risk to the Brazilian population from this source.