Keywords: 
• chrysanthemum tea /
• arsenic /
• infusing options /
• risk assessment /
• human health

Abstract: Chrysanthemum tea is a kind of popular tea around China. However, the improper dryness and producing processing of chrysanthemum might form the heavy-metals contamination, especially for arsenic combined with sulfur mines. Contents of As in samples of chrysanthemum tea from markets were investigated using HNO₃/H₂O₂ mixture in the high pressure sealed container and measured using atomic fluorescence spectrometry (AFS). Moreover, screening of the optimum ways of making tea was conducted using the samples with As contents above the safety standard (standard of agriculture of the People's Republic of China:green food herb-tea). Allowable daily intake (ADI) standard value from Food and Agriculture Organization/World Health Organization (FAO/WHO) was used for preliminary assessment of As risk to human health. Results showed that As contents in chrysanthemum tea ranged from 0.01 to 3.52 mg·kg^-1. As contents in 91.1% of samples was lower than the limited standard of green food herb-tea (0.5 mg·kg^-1). The highest As content in all samples was 3.52 mg·kg^-1 in Qi chrysanthemum for herbal medicine. Arsenic contents in 8 samples exceeded the standard of green food herb-tea, which are Qi white chrysanthemum (2 samples), Hangzhou chrysanthemum (2 samples), Huangshan chrysanthemum (1 sample), wild chrysanthemum (1 sample), Qi chrysanthemum for herbal medicine (1 sample) and chrysanthemum morifolium (1 sample). 75% of all samples with As contents above the safety standard are not packed. The samples of Hangzhou chrysanthemum and Qi chrysanthemum for herbal medicine with high As contents were used to study the brewing and drinking method. Specifically, boiling water at the mass ratio of water to tea of 25:1 was poured into cup for 5 min to wash the tea; then boiling water was added into cup and kept for 5 min to 20 min. Maximun daily intake of arsenic through chrysanthemum tea ranged from 43.7 to 169 μg·d^-1, and the percentage of the daily intake of arsenic in chrysanthemum tea to ADI established by FAO/WHO was in the range of 34.1% to 132%. The maximum daily intake of arsenic via Qi chrysanthemum for herbal medicine to ADI was higher than 100%, indicating that arsenic in some types of chrysanthemum tea from markets had an unnegligible potential risk to human health. The daily intake of arsenic from chrysanthemum tea after being washed was in the range of 13.1 and 36.3 μg·d^-1, and accordingly the percentage of the daily intake of arsenic in chrysanthemum tea to ADI wasfrom 10.3%~28.4%. After chrysanthemum was washed, the level of arsenic daily intake decreased significantly (P < 0.01). Therefore, it is better to wash chrysanthemum once before drinking chrysanthemum tea.