Safety evaluation of heavy metal elements in Yunnan edible yam
Using atomic absorption spectrometry and atomic fluorescence spectrophotometer, the total contents of Cu, Zn, Pb, As in Yunnan different kinds and producing areas of edible yam were determined, and the safety of these heavy metal elements was evaluated. The results were as follows:(1)The total contents of Cu, Zn, As didn't exceeded the limits of standards, but the contents of Pb in seven samples exceed the limits.(2)The single factor pollution index of heavy metals in the order of PbCuZnAs. The single factor pollution index of Pb was more larger.(3)Excluding the three samples, the comprehensive pollution index of other samples were higher than the warning line.