Fung K F, Carr H P, Poon B H T, Wong M H
Croucher Institute for Environmental Sciences, Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong, PR China.
Chemosphere. 2009 May;75(7):955-62. doi: 10.1016/j.chemosphere.2009.01.003. Epub 2009 Feb 23.
This study project aimed to investigate the concentrations of aluminum (Al) in tea products available in Hong Kong markets. Tea samples consisting of 47 different tea bags and 28 samples of tea leaves were analysed for concentrations of Al. All tea samples released Al (0.70-5.93 mg L(-1)) during a standard infusion period. In comparison to the Joint FAO/WHO Provisional Tolerable Weekly Intake guideline of 7 mg Al kg(-1) body weight, it was concluded that tea made with these tea leaves will not impose adverse human health impacts. The relative effects of age, soil available Al, and genetic differences on the levels of Al accumulated by tea bushes were investigated. It was found that there was no definite trend between the amount of Al accumulated and the age of tea bushes. The soil available Al influenced the levels of Al in Camellia sinensis to a certain extent, but it was evident that the ability of different varieties of C. sinensis to accumulate Al was variable. C. sinensis accumulated Al in all stages of growth. Young seedlings had lower contents of Al while the mobility of Al within the tea bushes was high. In a manner typical of hyperaccumulators, Al was not retained in the roots, but was consistently transported to the shoots. Aluminum in the tea bush was distributed between the different parts in the following order: mature leaves>roots>branches>young leaves.
本研究项目旨在调查香港市场上茶叶产品中的铝（Al）浓度。对47种不同茶包和28个茶叶样本进行了铝浓度分析。在标准冲泡期内，所有茶叶样本均释放出铝（0.70 - 5.93毫克/升）。与粮农组织/世界卫生组织联合临时每周耐受摄入量指南中规定的每千克体重7毫克铝相比，得出的结论是，用这些茶叶制成的茶不会对人体健康造成不利影响。研究了年龄、土壤有效铝和遗传差异对茶树积累铝水平的相对影响。结果发现，茶树积累铝的量与树龄之间没有明确的趋势。土壤有效铝在一定程度上影响了茶树中的铝含量，但很明显，不同品种的茶树积累铝的能力是可变的。茶树在生长的各个阶段都积累铝。幼苗中的铝含量较低，而铝在茶树中的移动性较高。以超积累植物的典型方式，铝不会保留在根部，而是持续运输到地上部分。茶树中的铝在不同部位的分布顺序如下：成熟叶>根>枝>幼叶。
