Investigation And Analysis Of Potential Safety Factors Influencing Tea-drinking In Shangluo

It is well known that drinking tea is beneficial for human health and fitness. Nowadaysmore than2billion people in the world have habit of drinking tea. In recent years, theincreasing incidence of pollutant emissions, followed by the rapid development of economy,results in the damage of ecological environment in the tea production areas of China. Moreand more people are concerning about the potential hazards of pesticide residues, heavymetals and biotoxins. The pollution of soil heavy metals and the improper use of pesticidesare the two main causes leading to the out of maximum limits of heavy metals and pesticideresidue in tea garden. The presence of these problems not only affects the tea quality andendangers the human health and life, but also is the biggest barrier to hinder the developmentof tea industry. Therefore, it is meaningful to investigate the contents and distributions ofheavy metals and pesticide residues in tea and analyze the origin of local tea.This research mainly determined the contents of heavy metals such as Pb、As、Cr、Cu andFe in the soil and tea leaves and evaluated the environments of tea garden based on theenvironmentalrequirements of pollution-free. The contents of heavy metals were alsocompared and analysed in soil and tea leaves. The source and pathway of heavy metalpollution were detected by means of absorbance features of heavy metals in tea tree. The typeof pesticide pollution and geographicaldistribution were studied based on the detection ofpesticide residues in tea leaves. The main purpose of this study is aimed at providing ascientific basis to prevent and control the pollution of heavy metal and pesticide and thuspromoting the development of tea production.The main conclusions are shown as below:(1)The overall soil environment of tea garden in Shangluo is good and not polluted byheavy metals. The Pb content in tea leaves is far lower than the limit required by the nation(1.0mg/kg), which is suitable for the development of green and pollution-free tea. (2)Although big differences of heavy metal contents are found in tea leaves fromdifferent region, the contents of As, Pb, Cu and Cr are all within the maximum limit ofgovernment standard, which meets the basic requirement for developing pollution-free tea.(3)Five aspects could be used to account for the heavy metal pollution:1.The soil parentheavy metals was absorbed by transfer tea tree and then transferred into tea leaves;2.Theheavy metals in the fertilizer first were transferred into soil and then tea leaves;3.Theenvironmental pollution such as the automobile exhaust, flue gas produced in life and thenadsorbed by soil or tea tree;4.The heavy metals in the tea-making machine were transferredinto tea leaves in the tea processing;5.Long-term fertilization and soil acidification result inthe change of existence state of metals from unavailable to available, which give anabsorption and then the transfer to tea leaves. The above five potential reasons are interactiveand performs differently in different tea garden.(4)Ecological tea garden has a good ability of self-purification and sustainabledevelopment, which can resist all kinds of pollutions from all aspects and fundamentallyimprove the tea quality. Therefore, it is necessary for developing ecological tea garden inShangluo area because of its good natural environment originated from Qinling Mountain andpromoting the ecological tea garden to enhance the tea quality.