http://www.newsweek.com/are-fukushima-radioactive-particles-california-wine-harmful-1039678

Radiation produced by Japan's Fukushima nuclear disaster has been found in Californian wine almost seven years after the event, according to a study published on the preprint server arXiv.org—but the good news is that it won't harm you.

In March 2011, a 9.0 magnitude earthquake and powerful tsunami struck Japan, causing a meltdown of the reactors at the Fukushima Daiichi nuclear power plant, which released radioactive material into the surrounding areas.