Q&A: Japans Nuclear Crisis
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Jonathan M. Links, PhD is Professor and Deputy Chair, Environmental Health Sciences; Director, Public Health Preparedness Programs, Johns Hopkins Bloomberg School of Public Health; Deputy Director, Johns Hopkins Office of Critical Event Preparedness and Response (CEPAR)
HOW NUCLEAR RADIATION TRAVELS AND ITS EFFECT OF THE BODY
Q: How does the radiation from the nuclear plant spread? Does it freely travel through all material including air, water, earth? What is the least and most resistance material to nuclear radiation? What is the affect of radiation over the human body? What is the most affected part of the body?
A: Radioactive releases would start in air (and certainly air is the primary vector for transport over large geographic distances). Some radioactivity would settle out (“fallout”) onto the ground, getting into soil, plants, and animals. “Resistant” materials are those that are unaffected by radiation. In our bodies, the skin is relatively radiation-resistant. “Shielding” materials are those that absorb radiation (e.g., lead for x-rays and gamma-rays). The distribution of radioactivity and the irradiation pattern (i.e., internal vs. external) depend on the sources of exposure. This also then determines the most at-risk organ or part of the body.
DETECTING RADIATION LEVELS
Q:Who is responsible for telling us if radiation levels in our city are high? If high levels are present, how long does the danger last?
A: EPA at the Federal level, and each state’s health department, environment and/or natural resources department, and each large city’s agencies, monitor air and water on a multi-times-per-day basis routinely. This monitoring should pick up any increases ... which is in fact how we know about the elevated levels that occurred in some states after the releases of radioactivity from the Japanese reactor. Of importance, those levels are FAR below what would constitute a public health risk, indicating the monitoring is very sensitive (which would give us plenty of warning).
RADIATION IN THE UNITED STATES
Q: Iodine-131 has been detected in Florida and has been attributed to the Japanese reactor releases. It was detected at an extremely low level comparable to the levels of this isotope generated by solar radiation. If further significant releases in Japan occur, are there steps that U.S. citizens should take to reduce risk of exposure, if so, what are they?
A: Again, the detection of I-131 in multiple states is a case of very sensitive detection capability. On the one hand, such sensitivity means we won’t be caught unawares. On the other hand, there’s a danger of causing unnecessary alarm. Were the levels to rise to a point of public health risk, which is not expected to actually happen, then potassium iodide may become recommended, especially for children.
Q:Why were Nagasaki and Hiroshima inhabitable after 1945 but Chernobyl not after its meltdown? What’s the difference?
A: The public health difference is the difference in radionuclides, amounts of radioactivity, and environmental conditions that influence the short- and longterm distribution of the radioactivity in the environment.
OVERCOMING THE FEAR OF RADIATION AND LEVERAGING ITS BENEFITS
Q: As a scientist, do you ever foresee a time when we can overcome our fear of radiation and our inability to leverage its potential?
A: Paul Slovic, a psychologist, is the guru of risk perception. He has lists of factors and characteristics that drive perception of risk; radiation is his favorite example, because it has all of the characteristics that increase risk perception: it can’t be sensed, exposure is involuntary, the risks are not fully understood, the risks are delayed (e.g., cancer), exposure is potentially fatal, etc. In such a situation, it’s hard to picture completely overcoming the fear.
OVERCOMING THE FEAR OF RADIATION AND LEVERAGING THE BENEFITS OF NUCLEAR
Q: As a scientist, do you ever foresee a time when we can overcome our fear of radiation and our inability to leverage its potential?
A: Paul Slovic, a psychologist, is the guru of risk perception. He has lists of factors and characteristics that drive perception.
FOOD SAFETY
Q: What can informed citizens do to reduce the quantity of food they consume that contains Fukushima radiation? Will ocean fish contain Fukushima radiation for years, even centuries to come (considering half lives of some elements)? Aren’t we already eating food containing Chernobyl, Pacific Nuclear test bombs, and 3 Mile Island radiation?
A: The challenge is that radioactivity (from all sorts of natural sources) is already all around us ... and in our bodies. I don’t find it helpful to think in terms of “zero” exposure, so I don’t find it helpful to think in binary (yes/no) terms of contaminated food or not. Having said that, aggressive monitoring of foodstuffs from Japan has been ongoing since the event.
Q: Can packaged food become contaminated?
A: Radioactivity cannot subsequently contaminate food that is packaged in an intact package. Tinned or plastic-wrapped food is protected from radioactivity as long as the food is sealed, WHO states.
JAPAN’S FUTURE GENERATION
Q: What type of public health impact, if any, might this recent event have on the future generation of survivors?
A: Although the extent of long-term contamination and doses to the public are not yet fully known, the most devastating effects of radiation are seen in children and pregnant women, as fetal development is characterized by a rapid reproduction and splitting of cells. Radiation exposure, therefore, can cause genetic mutations and severe deformities in developing fetuses.
