Radioactivity measurements of green tea leaves from Japan after the Fukushima incident

TL;DR

This study analyzes green tea leaves from Japan and other Asian countries for radioactivity levels, focusing on fallout from the 2011 Fukushima incident, revealing radionuclide distribution patterns across regions.

Contribution

It provides the first detailed comparison of radionuclide contamination in green tea leaves from various Asian producers post-Fukushima.

Findings

Japanese samples contain 137Cs and 134Cs isotopes.

All samples have about 500 Bq/kg of 40K.

Most recent Japanese samples show fallout radionuclides.

Abstract

A series of 32 green tea leaves samples from different Asian producers were analyzed by direct {\gamma}-ray spectrometry at the PRISNA facility in Bordeaux. All the samples contain about 500 Bq/kg of 40K and 10 Bq/kg of 210Pb. As expected, most of the recent Japanese samples contain also the 137Cs and 134Cs radio-isotopes, whose activity distributions are studied as a function of the geographical origin in order to get an insight on the outspread and fallout of radionuclides stemming from the 2011 Fukushima Dai-ichi Nuclear Power Plant incident.