California wine has received glowing reviews for the past decade, but a group of French researchers are now saying that the juice from Napa also contains another glowing element— Cesium-137. According to scientists Université de Bordeaux, radioactive fallout from Daiichi nuclear power plant in Fukushima, Japan seven years ago found its way into the wine. The good news is that the trace amounts of the isotopes are small and not harmful. So, drink on!
“In January 2017, we came across a series of Californian wines from vintage 2009 to 2012,” Michael S. Pravikoff and Philippe Hubert wrote in a new paper. “The Fukushima incident resulted in a radioactive cloud that has crossed the Pacific Ocean to reach the west coast of the United States. And in Northern California, there is the Napa Valley. The idea was then to see if, as is the case in Europe following the Chernobyl accident, we could detect a variation in the cesium-137 level in these wines.”
On March 11, 2011, the magnitude 9.0 Tohoku earthquake sparked a massive tsunami off the coast of Japan. Subsequently, the Fukushima reactors shut down, but the generators required to power the cooling system were inoperable. In the following days, three of the reactor units melted down and released large amounts of radioactive material into the atmosphere.
Pravikoff and Hubert previously studied different methods of dating wine. In 2001, they began exploring for Cesium-137 particles. The basic idea was that nuclear testing is a modern phenomena and above ground detonations are relatively uncommon. As a result, the particle allowed them to identify modern wines that were being passed off as older, rare vintages.
After discovering some California bottles in a local French market, the pair decided to experiment with them as well. The researchers tested 18 bottles of California Cabernet Sauvignon and Grenache rosé from each vintage between 2009 and 2015. (The Grenache was produced in Livermore Valley and Central Valley, while the Cabs all hailed from Napa.)
The results showed that the radioactive element began appearing in the vintages after the 2011 disaster. Each subsequent vintage yielded an increasingly higher level of Cesium. In the paper, the academics posited that the trend will continue for dozens of years more.
But, don’t panic! The scientists were quick to note that the levels present are far too low to cause any health risks. In fact, many French wines also tested positive for radioactive particles following the Chernobyl meltdown.