Experts pore over contaminants in Japan's radioactive spill
Published: 22/03/2011 01:00
Authorities across Asia stepped up checks this week on Japanese imports after radioactive contaminants showed up in food and water in quake-stricken Japan following blasts at a nuclear plant last week.
Experts are most worried about three radioactive substances — iodine-131, caesium-134 and caesium-137 — all of which can cause various types of cancer years later.
Caesium-137 is of particular concern as it can stay in the environment and potentially cause havoc for hundreds of years. It takes 30 years for this contaminant to lose its power by half — what experts refer to as a "half life".
At this rate, it would take at least 240 years for the contaminant to exhaust all its radioactivity.
"Caesium-137 can last for hundreds of years. If exposed, one can get spasms, involuntary muscular contractions and may lose the ability to walk. It also causes infertility. High doses will also damage a person’s DNA and cause cancer later," said Lee Tin-lap, an associate professor at the Chinese University’s School of Biomedical Sciences in Hong Kong.
But a few experts stressed there was no need for panic yet.
Levels of caesium-137 detected in spinach in Japan over the weekend stood at an average of 350 becquerels per kilogram, well below the European Union’s limit of 1,000 becquerels for dairy produce and 1,250 for all other food items.
"Becquerels are like atoms," said Pradip Deb, senior lecturer in Medical Radiations at the School of Medical Sciences, Royal Melbourne Institute of Technology University.
"A liter of milk has billions and billions of atoms … and this is just 350."
Caesium-134 has a half-life of 2 years, which will take about 20 years for it to become harmless.
The radioactive spill has prompted food checks in the Philippines, South Korea, China, Singapore and Malaysia. In addition to iodine and caesium, Thailand is also looking out for Strontium 90.
Higher levels of radioactive iodine
Milk samples in Japan, however, have been found to contain an average of 1,210 becquerels of iodine-131 per kilogram, well over the limit of 500 becquerels imposed in the EU.
Japanese spinach has also been found with an average of 10,450 becquerels of iodine-131 per kilogram, more than 5 times the EU limit.
One mitigating factor though is that iodine-131 has a half life of 8 days, which means it will take 80 days to lose all its radioactivity — assuming there is no fresh radioactive spillage.
"You can’t control radiation. It’s already there, but you can take preventive action (by not consuming any radioactive food that is tainted with iodine-131 for 80 days)," Deb said.
Radioactive material is carried by tiny moisture droplets in the air. It can then be directly inhaled into the lungs, get washed down by rain into the sea and into soil and eventually contaminate crops, marine life and drinking water.
Radioactive substances are dangerous because they can cause changes or mutations in DNA, which may then go on to cause cancer. While the human body can repair DNA changes or damage, a person is only safe if the repair process happens faster than the time it takes for the damaged or mutated DNA material to replicate.
Experts agree that children and fetuses are most at risk because their cells divide at a faster rate than adults. They also consume more milk, which puts them at greater risk.
Provide by Vietnam Travel
Experts pore over contaminants in Japan's radioactive spill - International - News | Vietnam travel | Vietnam in photo | vietnam travel company
You can see more
- Events welcome Italian friendship
- 70,000 sea tourists travel to Vietnam
- PM wants stronger oil and gas cooperation with Russia
- China sentences four to death for murders on the Mekong
- Viet Nam to boost trade, investment ties with Laos
- Russian Prime Minister to visit Vietnam
- Travel Picks: Top 10 spookiest destinations for Halloween
- Mobile revolution, economy trip up tech giants
enews & updates
Sign up to receive breaking news as well as receive other site updates!
- 6 percent GDP growth rate may be unattainable
- Fuel price, excursion fee hikes counteract tourism promotion programs
- Overseas Vietnamese wins TV's Master Chef
- Striker Cong Vinh plays for a J-League club
- Vietnamese prawn and noodle salad with lime, lemon grass and ginger dressing
- Tour operators launch lucrative promotions
- Vietnam's US trade surplus hits new heights
- The vestige - Gia Long waterfall
- Great landscape in Moc Chau
- An excursion on still water in Van Long
http://www.vietnamtourism.org.vn " Vietnam Tourism: Vietnam Travel Guide, Culture, Travel, Entertainment, Guide, News, and...
http://www.minmaxtravel.com/ " Customize & Book Vietnam tours, Cambodia tours and Laos tours with Travel Experts. Read...
http://travel.org.vn " Vietnam culture
http://www.visithalongvietnam.com/ " Halong Bay Vietnam, visit halong vietnam, all cruise in Halong bay,
http://www.nccorp.vn " Vietnam travel, vietnam travel news, vietnam in photos
http://www.vietnamtourism.org.vn " The official online information on culture, travel, entertainment, and including facts, maps,...