title: Composition, distribution and risk of total fluorine, extractable organofluorine and perfluorinated compounds in Chinese teas.
abstract: To explore the residual characteristics of fluorine and perfluorinated compounds (PFCs) in tea, the total fluorine (TF), extractable organofluorine (EOF) and PFCs in 19 Chinese commercial teas of five categories were measured using cyclic neutron activation analysis combined with HPLC-MS/MS. The results showed that fluorine mainly existed as inorganic fluorine in teas, and identified fluorine (∑PFCs quantified as F) only accounted for 0.023-0.41% of EOF, indicating that most EOF in tea were still unknown. 50-99% of ∑PFCs in tea were short-chain (C⩽6), while perfluorooctanoic acid was the typical PFCs residual species. Less fermented teas contained significantly higher PFCs (mean, 20ng/g) than more fermented teas (3.0ng/g, p<0.01), suggesting that microbe may degrade PFCs during fermentation. The highest TF content was discovered in Hubei brick tea, which poses risk of fluorosis, whereas PFCs residues in teas caused no immediate harm.
authors.affiliation: College of Physics and Energy, Shenzhen University, Shenzhen 518060, China; Brandeis University, Waltham 02453, MA, USA. Electronic address: zhangrb91@aliyun.com.
authors.forename: Ruobing
authors.initials: R
authors.lastname: Zhang
authors.affiliation: College of Physics and Energy, Shenzhen University, Shenzhen 518060, China. Electronic address: zhangh@szu.edu.cn.
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
authors.affiliation: College of Physics and Energy, Shenzhen University, Shenzhen 518060, China. Electronic address: chenqingwusiyi@163.com.
authors.forename: Qingwu
authors.initials: Q
authors.lastname: Chen
authors.affiliation: College of Physics and Technology, Dalian University, Dalian 116622, China. Electronic address: logicjiluo@sina.com.cn.
authors.forename: Ji
authors.initials: J
authors.lastname: Luo
authors.affiliation: Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China. Electronic address: chaizf@ihep.ac.cn.
authors.forename: Zhifang
authors.initials: Z
authors.lastname: Chai
authors.affiliation: Food Inspection Center of Shenzhen Entry-exit Inspection and Quarantine Bureau, Shenzhen 518045, China. Electronic address: jincansh@263.net.
authors.forename: Jincan
authors.initials: J
authors.lastname: Shen
mesh_terms: D028241:Camellia sinensis; D002210:Caprylates / Q000032:analysis*; D005459:Fluorides / Q000032:analysis*; D005461:Fluorine / Q000032:analysis*; D005466:Fluorocarbons / Q000032:analysis*; D053719:Tandem Mass Spectrometry; D013662:Tea / Q000737:chemistry*
chemical_list: D002210:Caprylates; D005466:Fluorocarbons; D013662:Tea; D005461:Fluorine; C023036:perfluorooctanoic acid; D005459:Fluorides
keywords: Beverage safety; China; Cyclic neutron activation analysis; Extractable organofluorine; HPLC-MS/MS; Perfluorinated compounds; Tea; Total fluorine