| The problem of pollutant residue in tea is increasing because of the pollution of environment, the unbalance of zoology, and the extension of tea industry. In recent years, many countries stipulated more strict limits for heavy metal and pesticide residue in tea. To serve as a country where tea industry is a big Export-oriented industry,Our tea industry is still suffering from many safety and health problems such as pesticide residue and heavy metal.In this paper we screened out main pollutants in tea which came from every city and town belonging to Lishui, according to results of recognition analysis of pesticide residue and heavy metal and foreign advanced standards of limits. Furthermore, we constructed a tea safety and risk evaluation model by means of fuzzy mathematics. On the one hand, we made full use of the results above and principle of fuzzy matrix operation, giving the overall conclusion including:all the risk factors of tea were ranged in sequence according to degree of risk;eight places of origin were ranged in sequence according to pollution level.On the other hand,we compared this method with the actual and standard one used in foreign countries, with a view to confirming the validity of this method and the accuracy of final results. Besides,we also discussed such a doubt in this article that manufacturing and packaging procedure could or not affect quality of the products.The results showed that tea was seriously polluted by heavy metal in the manufacturing and packaging procedure. The major pesticides in spring tea were some pyrethroids and organophosphorus, BHC and DDT especially BHC still can be detected in most of samples,though they were minim. Acephate has the more relevance ratio and higher concentration than other organophosphorus, dichlorovos, methamidophos,dimethoate also can be detected.The results showed that the concentration of pesticides may be changed in the manufacturing procedure, but there was no obvious change in the packaging procedure.
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