[The fate of dioxins during green tea manufacture]

Dioxin concentrations and homologue profiles were examined in plucked new shoots, crude tea and its hot water extracts, soils and atmosphere in tea orchards. The rate of dry provisions in crude tea has increased 4 times as that of the plucked new shoots. However, dioxin concentrations except O8CDD in crude tea have increased only 2 to 3 times as those of the plucked new shoots. O8CDD concentration increased remarkably during processing. Little dioxins were detected in hot water extracts of crude tea leaves.