nuclear-news

The News That Matters about the Nuclear Industry Fukushima Chernobyl Mayak Three Mile Island Atomic Testing Radiation Isotope

Even very low level “background” radiation is harmful

radiation-warningRecent evidence on the risks of very low-level radiation, Dr Ian Fairlie,  January 17, 2013“…….I’ve previously shown  that a great deal of evidence supports the LNT hypothesis and indicates radiation effects well below 100 mSv.

But in recent months, a flurry of epidemiological studies go further than merely refuting ill-informed articles. They indicate adverse effects to people exposed to very low doses from medical CT scans and other clinical procedures; to infants living near nuclear power stations; and to Chernobyl clean-up workers. They even reveal adverse effects from background radiation to which all of us are exposed.

Together they reveal a pattern of higher-than-expected risks from very low exposures to radiation.

1. Background Radiation

Perhaps the most eye-opening of the recent studies concern background radiation. Most people think that background radiation levels (typically 2 to 3 mSv per year) are very low and are of little concern. But recent authoritative studies clearly indicate that background radiation is not harmless.

For example, a team of British scientists based at the University of Manchester, Imperial College and the UK Health Protection Agency has been examining this matter. Using two leukaemia risk models and estimates of red-bone-marrow doses received by children from background radiation, the team initially estimated that 20% of the childhood leukaemia cases in Great Britain were attributable to background radiation (Wakeford et al, 2009) – see references at end.

This surprising result was first refined to 15% of GB childhood leukaemias (Little et al, 2009) (Kendall et al, 2011), then the team predicted the risk rate from background gamma radiation. After conducting a large record-based case–control study with 27,000 cases and 37,000 controls to test associations between childhood cancer and natural background radiation, the authors estimated that the excess risk of childhood leukaemia was 12% per millisievert of cumulative red bone marrow dose from background gamma radiation (Kendall et al, 2012). The most recent comprehensive review (Wakeford, 2013) confirms these estimates.

Just to make sure the point gets across, these studies mean that all children will receive about 1 mSv of gamma radiation from background radiation each year and this results in their leukemia risk being increased by 12%.

It’s well known that leukemia is closely associated with radiation exposures and that children are more sensitive to radiation than adults. But the new evidence is not just from childhood leukemias, it comes from radon studies as well.

 

In Canada, following a survey of 14,000 homes with a geometric mean radon concentration of 42 Bq/m³, Chen et al (2010) from the Radiation Protection Bureau of Health Canada estimated that 16% of lung cancer deaths in Canada were attributable to indoor radon. However this fits slightly awkwardly with another large (7,000 cases and 14,000 controls) risk assessment of radon exposures (Darby et al, 2006) which estimated an excess relative risk of lung cancer of 16% (95% CI 0.05-0.31) at an average radon concentration of 100 Bq/m³. Whichever of these scientific teams turn out to be correct, the cancer risks from background radon exposures are still higher than were expected even just a few years ago.

Another very large Canadian study by Turner et al (2012) of over 800,000 Americans found that indoor radon was significantly associated with deaths from chronic obstructive pulmonary disease, ie chronic bronchitis and/or emphysema. The hazard ratio was 1.13 per 100 Bq·m?3(95% CI = 1.05–1.21). There was a significant positive linear trend in deaths with increasing categories of radon concentrations (p<0.05). For comparison, the UK HPA’s recommended Action Level for radon is 200 Bq·m?3: indoor concentrations above this level require remediation.

And in areas with high levels of natural background radiation (usually from monazite sands), Møller and Mousseau (2012) studied radiation effects in local peoples and found increased risks in immunology, physiology, mutation and disease. They stated “.. if we see effects at these low levels, then we have to be thinking differently about how we develop regulations for … intentional exposures to populations, like the emissions from nuclear power plants, medical procedures, and even some x-ray machines at airports”.http://www.ianfairlie.org/news/recent-evidence-on-the-risks-of-very-low-level-radiation/

January 18, 2013 - Posted by | 2 WORLD, health, Reference

2 Comments »

  1. […] Even very low level “background” radiation is harmful (nuclear-news.net) […]

    Pingback by radiological imaging « deemagclinic | January 18, 2013 | Reply

  2. […] and the Risks of Nuclear Power with Dr. Gordon Edwards. 1 hour video presentation ☢ Even very low level “background” radiation is harmful ☢ It’s the uranium, stupid! France’s war in Mali ☢ World Nuclear Electricit​y […]

    Pingback by Eradicating Ecocide in Canada - No Nukes News Jan 21, 2013: Resilience | January 24, 2013 | Reply


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: