Correlation analysis between main chemical constituents of tobacco leaves and endogenous harmful components in mainstream cigarette smoke was conducted. Leaf stalk positions exhibited a high relation with endogenous harmful components and hazard index( H). Upper stalk position leaves had greater release of 1-butanone,4-( methylnitrosoamino)-1-( 3-pyridinyl)-( NNK),B[a]P,HCN,NH3 and phenol in mainstream cigarette smoke,and a higher hazard index than middle position leaves except for crotonaldehyde,which had ...