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165432 
Journal Article 
Effect of liming and seasonal variationn lead concentration of tea plant (Camellia sinensis (L.) O. Kuntze) 
Han, WY; Shi, YZ; Ma, LF; Ruan, JY; Zhao, FJ 
2007 
Yes 
Chemosphere
ISSN: 0045-6535
EISSN: 1879-1298 
PERGAMON-ELSEVIER SCIENCE LTD 
OXFORD 
66 
1 
84-90 
English 
16844190 
WOS:000243743700011 
Teas a widely consumed beverage. However, recent studies revealed that there were anncreasing numberf casesf tea products exceeding the former maximum permissible concentration (MPC)n China for Pb (2 mg kg(-1)). Tea Pb contaminations anssue affecting trade and consumer confidence. Root uptakef Pb could contribute significantly to Pb accumulationn tea leavesue to the strong acidityf many tea garden soils. We conducted pot and field experiments to evaluate the effectf limingn Pb uptake by tea plantsn two highly acidic soils (pH3.6). Additionsf CaCO(3) significantlyncreased soil pH by up to 1 unit andecreased soil extractable Pb by up to 32%. Liming resultedn aecreasen the proportionf Pbn the exchangeable and carbonate-bound fractions, with a concurrentncreasen the fractions bound to Fe/Mnxides and residues. Liming significantlyecreased Pb concentrationsf fine roots, stems and new shootsf tea plantsn the pot experiment. In the field experiments, the effectf liming was not significanturing the first year following CaCO(3) application, but became significanturing the second and third years and Pb concentrationn the new shoots wasecreased by approximately 20-50%,ndicating that limingf acidic tea garden soilss an effective way to reduce Pb contaminationf tea. The study also reveals aistinct seasonal variation, with Pb concentrationn the new shoots following therderf spring>autumn>summer. 
Calcium Carbonate/pharmacology; Calcium Compounds/ pharmacology; Camellia sinensis/rug effects/metabolism; Lead/analysis/ metabolism; Oxides/ pharmacology; Plant Leaves/drug effects/metabolism; Seasons; Soil Pollutants/pharmacology