image credit: Shane Anderson, U.S. National Oceanic and Atmospheric Administration

About a month after the nuclear disaster at Fukushima Daiichi nuclear power plant, radioactive particles were detected in giant kelp samples off the California coast.

The level 7 nuclear incident resulted from the earthquake and tsunami that devastated the region around Fukushima, Japan in March of 2011.

In a recent study California State University marine biologists tested giant kelp up and down the coastline of the state, from Laguna Beach to Santa Cruz, and found radioactive iodine, suggesting that radiation that leaked from the damaged Fukushima reactors had reached California.

Levels 250 times higher than previous measurements were found in one sample.

From the San Francisco Chronicle:

Basically, we saw it in all the California kelp blades we sampled. [Iodine 131] has an eight-day half-life, so it’s pretty much all gone, but this shows what happens half a world away does effect what happens here. I don’t think these levels are harmful, but it’s better if we don’t have it at all.

–Steven Manley, CSU Long Beach biology professor

Kelp is among the fastest growing organisms on Earth and is the largest species of algae. Because it absorbs iodine, fish that feed on kelp could have experienced risk, though there is no published relevant research on how iodine 131 at these levels might affect fish.

From the Los Angeles Times:

The levels, while most likely not harmful to humans, were significantly higher than measurements prior to the explosion and comparable to those found in British Columbia, Canada, and northern Washington state following the Chernobyl disaster in 1986, according to the study published in March in the journal Environmental Science & Technology.

The radioactive iodine likely entered the ocean due to heavy rains that followed the meltdown at Fukushima.