Polycyclic aromatic hydrocarbons in teas using QuEChERS and HPLC-FLD

ABSTRACT

Polycyclic aromatic hydrocarbons (PAHs) are food-processing contaminants considered to be carcinogenic and genotoxic. Due to its drying process stage, teas may be contaminated with PAHs. The aim of the study was to validate an analytical method involving QuEChERS and HPLC-FLD for the determination of PAH4 in teas and evaluate the contamination levels in 10 different types of teas from Brazil. Recoveries varied from 54% to 99% and relative standard deviations from 1% to 21%. Limits of detection and quantification were from 0.03 to 0.3 µg/kg and 0.1 to 0.5 µg/kg, respectively. Mate tea presented the highest PAH levels, with PAH4 varying from 194 to 1795 µg/kg; followed by black (1.8–186 µg/kg), white (24–119 µg/kg), and green teas (3.1–92 µg/kg). Teas with lowest PAH4 were strawberry, lemongrass, peppermint, and boldo. Only trace levels of PAHs were detected in tea infusions, so apparently it would not affect PAH intake by Brazilian population.

KEYWORDS:

• Polycyclic aromatic hydrocarbons
• QuEChERS
• tea
• mate
• Camellia sinensis

Acknowledgements

This work was supported by the Fundação de Amparo à Pesquisa do Estado de São Paulo (Fapesp) under Grant 2012/19142-7. R.M.R. (Instituto de Química, UNICAMP, Campinas, SP, Brazil) thank CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico), Brazil for PIBIC/CNPq undergraduate student fellowship program.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by Fundação de Amparo à Pesquisa do Estado de São Paulo [2012/19142-7].