No Proof That X-ray Radiation Causes Cancer

The widespread belief that radiation from X-rays can cause cancer is based on an invalid paradigm for estimating low-dose radiation exposure risk, according to a new study.

According to researchers at Loyola University Medical Center (Maywood, IL, USA), the linear no-threshold (LNT) model, which is constantly used today to provide risk estimates for cancer resulting from any exposure to low-dose ionizing radiation, is unsound. They claim the paradigm, which is used for X-Rays and computerized tomography (CT) imaging, among others, is only theoretical, and has never been conclusively demonstrated by any empirical evidence.

The also reappraised the original studies, which date back more than 70 years, which concluded that the well-established cancer-causing effects of high doses of radiation are extended downward in a straight line down to zero dose level. They concluded that these risk estimates, defined by of the LNT model, are erroneous, as the original studies in fruit flies, which concluded there is no safe level of radiation, had not been done at truly low doses.

In fact, a study that actually exposed fruit flies to low-dose radiation wasn't conducted until 2009, and that study did not support the LNT model. Studies of atomic bomb survivors and epidemiological studies of human populations have also never conclusively demonstrated that low-dose radiation exposure can cause cancer. The new study refuting the LNT model and calling for its decisive abandonment was published in February 2016 issue of the American Journal of Clinical Oncology.

“The LNT model dissuades many physicians from using appropriate imaging techniques and discourages many in the public from getting proper and needed imaging, all in the name of avoiding any radiation exposure,” concluded corresponding author Prof. James Welsh, MD, and colleagues. “Any claim that low-dose radiation from medical imaging procedures is known to cause cancer should be vigorously challenged, because it serves to alarm and perhaps harm, rather than educate.”

Low-dose radiation exposure due to natural background radiation bathes every single person on Earth, at levels that vary annually from a few mGy to 260 mGy, depending upon where one lives on the planet. Irrespective of the level of background exposure to a given population, no associated health effects have been documented to date anywhere in the world. In fact, people are living longer today than ever before, likely due to improving levels of medical care, which include radiation exposure from diagnostic medical radiation, which are well within the background dose range across the globe.

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Loyola University Medical Center