A paper emitted this month by researchers at the University of Bordeaux Centre d'Études Nucléaires de Bordeaux-Gradignan (CNRS) in France revealed that levels of cesium-137 in the atmosphere rose as a result of the reactor accident, judging by Cali tipple tested before and after Japan's level-7 nuclear disaster.

It is believed a radioactive cloud released by the Fukushima Daiichi plant made its way across the Pacific and over to California's Napa Valley vineyards, where trace amounts of the highly soluble cesium isotope got into the grapes used to make the region's famed wines.

As a result, a typical bottle of Cali Cabernet Sauvignon doubled its cesium-137 activity from about 7.5 mBq per liter to around 15, which is – to use a technical term – sod all, but still quite interesting.

The cesium-137 levels vary by the type of wine, with bottles of rose showing lower concentrations than those of the darker Cabernet Sauvignon reds.

Radioactive cesium-137 has been detectable in wines for decades.

Thanks to the advent of nuclear weapons and their tests, every bottle of wine made since 1952 has at least some detectable level of cesium-137.

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