The story of a nuclear disaster and what can do you as a citizen scientist to help assess the residual aftermath.
[In the news – KQED Science recently spoke to project organizer Ken Buessler about the radiation in our ocean.]
Three years ago on March 11, 2011, a magnitude 9.0 earthquake and tsunami shook Japan. The loss of power that ensued eventually led to the Fukushima Daiichi nuclear power plant overheating. Four out of six reactors suffered meltdowns, spitting radioactive fallout into the atmosphere and directly into the ocean. 19,000 people died or went missing.
Almost immediately, the news ignited fears of how this would impact marine ecosystem and human health over time. Today, three years later, there is still no U.S. government agency monitoring the spread of radiation from Fukushima along the west coast or Hawaiian Islands.
In reaction to this, the Woods Hole Oceanographic Institution (WHOI) and the Center of Marine and Environmental radiation (CMER) are providing the equipment and the facilities to track the spread of radionuclides across the Pacific Ocean. Even further—they’re opening this process up to the public, to you. How Radioactive is Our Ocean? is a citizen ” science project that allows the public to propose sampling locations, raise the cost for testing and shipping of the supplies ($500-600), take samples and analyze 20 liters (about 5 gallons) of seawater for signs of radiation (cesium-137 isotopes) from Fukushima. Everything is provided by WHOI and CMER. There are three main ways that you can participate:
- Help the project reach their goal by donating to sample an existing site. Click “HELP FUND A LOCATION” on the main page and choose to support one of the many sites that are underway;
- Propose a new sampling site. Click “PROPOSE A LOCATION” and see what is involved. If accepted(we are trying to get spread of locations up/down coast), we ask for a donation of $100 and we’ll set up a fundraising webpage, add that page to our website, and send you a sampling kit once your goal of $550 to $600 has been reached.
- Donate to general capacity building and public education activities at CMER.
Here’s a video showing how you would take samples from locations near you:
How is radioactivity measured in the ocean?
“We live in a sea of radioactivity,” says Ken Buesseler, marine chemist at the WHOI. “The danger is in the dose.” Buesseler spent the bulk of his career studying oceanography and the spread of radionuclides from Chernobyl in the Black Sea. He goes on to explain:
The unit to describe the level of radiation in seawater samples is the Becquerel (Bq), which equals the number of radioactive decay events per second. This number is reported per cubic meter (i.e. 1,000 liters or 264 gallons) of water.
A typical water sample will likely contain less than 10 Becquerels per cubic meter (Bq/m3) from cesium-137. The amount of cesium-137 that leaked into the water as a result of Fukushima was in the penta-Becquerels (that’s 1,000,000,000,000,000 Becquerels). By comparing the amount of cesium-137, which has a relatively long 30-year half life, and cesium-134, which has a much shorter, 2-year half life, scientists can “fingerprint” the contamination from Fukushima and estimate how much was released into the Pacific. Is that much radiation significant? The world’s oceans contain many naturally occurring radioactive isotopes like potassium-40, which comes from the erosion and breakdown of rocks. Bananas, known for their potassium content, release about 15 Bq on average. That means that the radiation leakage was about the same as that of 76 million bananas, to put things in perspective. This is actually around and about (perhaps a little over) the amount of radiation Fukushima was allowed to dump into the environment before the disaster. However, WHOI and CMER still make the case that it would be important to monitor and track cesium-137 and cesium-134 levels in the ocean, given future projection.
How are marine species affected?
Because the cesium-137 isotope is soluble, it mixes well with ocean currents. “The spread of cesium once it enters the ocean can be understood by the analogy of mixing cream into coffee,” writes Buesseler. “At first, they are separate and distinguishable, but just as we start to stir the cream forms long, narrow filaments or streaks in the water.” After they form streaks, they blend in and are diluted (think about how coffee turns into a lighter color after you add cream). Fish and other forms of marine life can take it up and excrete it, depositing it in the sediment below. The marine life most contaminated with Fukushima radiation is found nearest to the reactor, but some species, like Bluefin tuna, are far-ranging and even migrate across the Pacific. When these animals leave the Northeast coast of Japan, some isotopes remain in their body, but others, like cesium-137 and cesium-134, naturally flush out of their system. If you’re interested in proposing a sampling location to help the WHOI and CMER study the distribution of radionuclides in the Pacific, get started with the project or help spread the word about it!
This post originally appeared on the SciStarter blog.
Image: EPA, ourradioactiveocean.org
Goodman, Amy. “Fukushima is an ongoing warning to the world on nuclear energy.” The Guardian. 16 January 2014. http://www.theguardian.com/commentisfree/2014/jan/16/fukushima-is-a-warning
Fukushima’s Radioactive Water Leak: What You Should Know http://news.nationalgeographic.com/news/energy/2013/08/130807-fukushima-radioactive-water-leak/
CMER public education links, such as ABCs of radioactivity http://www.whoi.edu/page.do?pid=119836