海南省市售苦丁茶和鹧鸪茶及茶汤中9种元素污染特征及健康风险评估

Pollution characteristics and health risk assessment of nine elements in commercially available Kuding and Partridge tea leaves and their infusions in Hainan Province

目的了解海南省市售苦丁茶和鹧鸪茶及茶汤中铝、铜、锰、铬、镉、铅、镍、砷、汞9种元素的含量,并估计饮用茶汤对人体健康风险。方法于2017—2018年在海南省采集市售苦丁茶和鹧鸪茶,采用微波消解-电感耦合等离子质谱仪检测茶叶及茶汤中9种元素的含量,采用美国环保署(the United States Environmental Protection Agency, USEPA)提出的THQ和HI评估茶叶和茶汤元素污染的人体健康风险。结果苦丁茶中镉含量均值为5.46 mg/kg,超标率为82.0%,鹧鸪茶9种元素含量均未超过国家标准限值。苦丁茶茶汤中存在Cd、Mn和Al含量超出国家生活用水限量标准,鹧鸪茶茶汤中存在Mn和Ni含量超过国家生活用水限量标准,并随着浸泡次数的增加其元素含量也随之降低。苦丁茶HI值为1.147,第一道茶汤至第三道茶汤HI值范围为0.341~0.117;鹧鸪茶HI值为0.346,第一道茶汤至第三道茶汤HI值范围为0.314~0.132。结论饮茶者应弃去第一浸茶汤,饮用海南省市售苦丁茶和鹧鸪茶茶汤无健康风险,但需要加强对苦丁茶中Cd、As和Mn,鹧鸪茶中Mn和As元素的监测。

Objective To understand the content of nine kinds of elements,including Al,Cu,Mn,Cr,Cd,Pb,Ni,As and Hg in commercially available Kuding and Partridge tea leaves and their infusions in Hainan Province,and to assess health risks associated with drinking their infusions.Methods Commercially available Kuding and Partridge tea leaves were collected in Hainan Province during 2017-2018,and the content of the nine elements in their infusions were determined by inductively coupled plasma mass spectrometry after microwave digestion.Health risks from pollution of the elements in the leaves and their infusions were assessed using the targeted hazard quotient(THQ)and hazard index(HI)recommended by the United States Environmental Protection Agency(USEPA).Results The mean of Cd content in Kuding tea leaves was 5.46 mg/kg,with the exceeding standard rate of 82.0%,but the content of the nine elements in Partridge tea leaves was within the national maximum permissible limits.The content of Cd,Mn and Al in Kuding tea infusions and the content of Mn and Ni in Partridge tea infusions were all higher than the national maximum permissible limits for drinking water,and the content of the above-mentioned elements in the tea infusions decreased with the increase of infusion times.The hazard index(HI)in Kuding tea leaves was 1.147,with a range of HI in the first infusion of tea to the third infusion of tea being 0.341-0.117.The HI in Partridge tea leaves was 0.346,with a range of HI in the first infusion of tea to the third infusion of tea being 0.314-0.132.Conclusion Tea drinkers should pour the first infusion of tea away.Sipping infusions of commercially available Kuding and Partridge tea in Hainan Province poses no significant health risks,but it is necessary to strengthen the monitoring on the content of Cd,As and Mn in Kuding tea leaves as well as Mn and As in Partridge tea leaves.