Similar to many of you, we at COA have been watching the news about the earthquakes and tsunami in
and the impacts on the nuclear facilities there. Our first and foremost concern goes out to the people in Japan and their families, as there has been such tremendous devastation and loss. Japan
We’ve been also concerned about the impacts of these
events on the ocean. Obviously, the tsunami and its flooding of coastal towns and cities have resulted in extensive marine debris and ocean pollution.
In addition, leaks from the nuclear power plants and discharges of contaminated cooling water have increased radiation levels in the ocean (and potentially groundwater) near the facilities. Radioactive iodine 131 was reported by the LA Times to be found at 7.5 million time the legal limit and radioactive cesium 137 was 1.1 million times the limit. Iodine has a half-life of 8 days, meaning that it breaks down by half in that time and results in shorter-term exposure risks, however cesium has a half-life of 30 years and will persist presenting a longer-term risk. Radiation can lead to cancer and defects in reproduction.
So what does this mean for marine life? Because of the salts and ions in seawater, fish and marine life are less likely to take up the radioactive elements than they would in a freshwater lake (See here for more info). Given the vast size of the Pacific, contaminated areas will probably be diluted minimizing the risks over larger areas. In fact, some experts say that the radiation will not pose a widespread danger to marine life. However, local impacts seem plausible. Testing of fish, shellfish and seaweed in for radioactivity is underway. Sand lances, small fish collected 50 miles from the nuclear facilities, were found to have high radioactive levels that were unsafe for human consumption. Another initial analysis of fish has shown that one in five had radioactive cesium but at low levels. We will have to continue to watch to see what happens…