Researchers are checking for radiation in what's being called "Kelp Watch 2014."
Scientist from Cal State Long Beach are testing the seaweed off the coast of California for contamination from radioactive ocean water from the damaged Fukushima power plant.
Back in March of 2011, the massive earthquake and tsunami off the Japanese coast devastated the plant and sent radioactive material into the ocean.
The researchers don't expect the contamination levels in the kelp to be high enough to harm humans, but can't say the same for the ecosystem the kelp supports.
Two more collections will be taken later this year.