History of the medical profession’s role in illnesses and death caused by nuclear radiation.

From Hiroshima to Fukushima to You, Dale Dewar, 4 July 2024 “…………………………………………………………………………………………………………. Are we still questioning the safety of ionizing radiation? Nuclear industry leaders are delighted to remind me that physicians are the leading causes of the radioactive “burden” that most people carry.

Inadvertent research in medicine

What is less well known is that the medical profession has inadvertently conducted research on radioactivity and, after the fact of the exposures, discovered correlations of injury with radioactivity. Only a few are listed here:

1. Radiation-Induced Meningiomas:

In the early 1900’s until after the discovery of topical anti-fungals^[2] in the late 1950’s, the treatment of choice for fungal or yeast infections of the scalp was irradiation, especially for Jewish children planning to immigrate to Isreal. The technique exposed the scalp to 5 – 8 Gy to the scalp, and 1.4 – 1.5 Gy to the surface of the brain. Initially it seemed like a safe thing to do.

But then reports of somnolence (sleepiness) lasting from 4 – 14 days in 30 of 1100 children occurred. By the 1930’s side effects included atrophic changes to the scalp, epilepsy, hemiparesis, emotional changes and dilatation of the brain’s ventricles.

The absolute death knell to the practice occurred in 1966 when University Medical Center (New York) published a study showing a dramatic increase in cancers among those irradiated. An increase rate of psychiatric hospitalizations was also noted.

Studies continue to roll in – the latent phase for meningioma is approximately 30 years but metastatic tumours may take over 40 years to develop. No one irradiates scalps for ringworm now.^[xvii]

2. Treatment of tuberculosis using chest fluoroscopy:

Between 1925 and 1954, one of the therapies for tuberculosis was collapse of the lung followed by x-Ray fluoroscopy. More than 2500 of these patients were followed for 30 years. Increases in the rate of cancer of the breast was not seen until about 10 to 15 years after first exposure^[3]. There were 147 breast cancers in the treated cohort compared to 113.6 in tuberculosis patients that were not treated with fluoroscopy. The researchers concluded that younger women were more likely to develop cancer and that the risk of developing cancer remained high for their entire lives.

The fluoroscopic and x-ray doses were known. Another finding from this study was that fractionated doses had the same risk of developing cancer as the single total dose.^[xviii]

3. Irradiation of the thymus gland and subsequent breast cancer

Young children normally have large thymus glands. With the advent of chest x-rays in the 1920’s, this large thymus was viewed with suspicion. Pediatricians feared that a large thymus could lead to respiratory problems. Until 1953^[xix]irradiation of the thymus was done to decrease its size.

The rate of breast cancer among woman who were so treated as children was three times that of those that were not treated. The cancers occurred when women were in their early 30’s, more than 25 years after irradiation.

Since the amount of radiation given to the thymus was quite low, researchers have become concerned about the rising tendency for CT scans of the chest either for diagnosis or treatment. Their results “underscored the importance of limiting radiation exposure in the youngest children as much as possible.”

4. CT scans of children’s heads following injuries.

Like many physicians wishing to comfort parents whose child had a concussion, I was pleased to be able to refer the child to a CT scanner when one became available in 1996. We all slept better at night thinking that a normal CT meant that the kid’s brain was ok.

Maybe we should not have.

A Canadian study of children receiving CTs to the head indicated that as few as four CT scans before the age of six could result in doubling the risk of leukemias, lymphomas and intracranial tumours starting about ten years later.^[xx]

5, Secondary cancers resulting from radiation treatment for cancer

Until recently second primary cancers were neither given serious thought nor studied. Most patients receiving radiation did not live long enough, the 15 to 20 years after their treatment, to display the side effects of ionizing radiation.

One of the first studies on this population indicated that the number of second cancers caused by radiation was as high as one person in five.

There are many criticisms of this study not the least of which is that the size of their sample was small and, at ten years, the length of time for the development of solid cancers was short, but the researchers still concluded that “an effort toward a reduction in their incidence is mandatory. In parallel, radiation therapy philosophy must evolve, and the aim of treatment should be to deliver the minimal effective radiation therapy rather than the maximal tolerable dose.^[xxi]

Arising from their work were estimations of dose associated with harm. They concluded that the incidence increased with the dose even though thyroid and breast cancers were observed following doses as low as 100 mGy and adults developed cancers following treatment doses as little 500 mGy. The risk of developing sarcoma (bone cancer) was 30.6 times higher for doses of more than 44 Gray than for doses of less than 15 Gray.

6. Side effects of ionizing radiation tracers and heart disease.

Research has shown that the lifetime risk of developing fatal cancer from the use of a radioactive tracer as in a PET or MIBI scan is 1 in 2000, in other words, it is lower than the lifetime risk of dying in a motor vehicle accident (1 in 108).^[xxii]

However, when Canadian researchers focused on their 82,861 patients who had heart attacks, they found that 77% underwent at least one cardiac imaging or therapeutic procedure involving low-dose ionizing radiation. By comparing populations, they found that for every 10 mSv of radiation there was a 3% increase in the risk of age- and sex-adjusted cancer over a follow-up period of five years.

Because five year follow-up is very short for the development of cancers, this is an underestimate, probably by a large factor…………………………………………………………………….. https://ionizingradiationandyou.blogspot.com/