Published: Wednesday, October 28, 2009 |
Canadian Press Amanda Gardner, Healthday Reporter
(HealthDay News) - Americans' exposure to radiation from medical procedures has exploded over the past few decades, to six times the level of 1980, a new report shows.
In 2006, almost 380 million diagnostic and interventional radiological procedures were performed in the United States, on top of 18 million nuclear medicine examinations.
"Back in about 1980, 15 per cent of radiation that the U.S. population got was from medicine and the rest was predominantly from natural background radiation," noted Dr. Fred Mettler Jr., U.S.
Representative to the United Nations Scientific Committee on the Effects of Atomic Radiation and a professor of radiology at the University of New Mexico in Albuquerque. "In the last 20 years, medical exposure has gone up between 600 and 700 per cent from what it was, and it is now the biggest source of radiation to the U.S. population."
"The issue," Mettler continued, "is that this is a controllable source. We regulate the effluent from nuclear power plants so the public doesn't get exposure but medical exposure is essentially unregulated. The largest source in the U.S. is essentially unregulated, and it's up to your family doctor or any other doctor to hand it out."
Mettler is lead author of a paper appearing in the November issue of Radiology that summarizes the conclusions of two previous reports on radiation sources in the U.S. Those reports were issued by the U.S. National Council on Radiation Protection and Measurements and the United Nations Scientific Committee on Effects of Atomic Radiation.
The findings are in line with previous studies, one of which attributed up to two per cent of all cancers to CT scans alone and another which concluded that cumulative exposure to radiation from CT scans increases the risk for malignancy by as much as 12 per cent.
The last comprehensive assessment of radiation exposure was conducted in 1980-1982, a veritable eternity by medical and scientific standards.
"We needed to get a grip on how much radiation the U.S. was getting and where it was coming from," Mettler said.
In the intervening years, the number of procedures performed has risen "by leaps and bounds," he said. "The biggest chunk of that is CT scanning, which has been growing at better than 10 per cent a year while the U.S. population is growing at less than 1 per cent."
Widely used as a diagnostic tool, CT scans provide detailed images of organs, allowing more accurate diagnoses of conditions such as cancer. But CT involves a higher radiation dose than most other imaging tests. According to this paper, CT provides half of the country's total radiation dose, even though it represents only 17 per cent of total procedures.
Emergency room physicians may be at the epicenter of the surge in scan use, Mettler said. "Twenty-five to 40 per cent of CT scans are ordered out of the ER," he noted. "The emergency physicians are in a tough box because they're worried about getting sued. And they tend to get patients who they haven't seen before. This is a one-time walk-in and their mantra is, 'We can't afford to miss anything.'"
Of course, the trend is not limited to the U.S., although it may be more extreme here. Globally, the per-capita annual dose from medicine has doubled in the past decade or so.
Still the U.S. leads the pack, with 12 per cent of all radiologic procedures and half of nuclear medicine procedures performed here.
"We have a little under 5 per cent of the world's population and 25 per cent of X-ray studies in the world and double and triple that of other developed countries," Mettler said. "Nobody thought about how much radiation goes with this."
But not all of uptick in scans has been unnecessary, said Dr. Robert Zimmerman, executive vice chair of radiology at Weill Cornell Medical Center in New York City.
"We don't really know how much of it is overuse. We do know some of it is overutilization, but CT is a valuable imaging modality. CT is a great test. There's no question that in the appropriate cases it's going to save lives."
There are things radiologists can do to curb its use, including reducing the doses, while manufacturers are working on new and improved machines, Zimmerman said.
Physicians can also tailor their use, thinking twice about using this type of technology in children, who are more sensitive to radiation and have longer to develop side effects.
"When I get a call for a CT scan, my first question is, 'How old is the patient?' If it's 40 or under my antennas go up and if they're 70 my antennas don't get so excited. Mostly my idea is a CT might be a good thing but you would like to think about radiation beforehand," Mettler said. "There's a lot of stuff going on now that isn't justified. Nobody's ever shown that many of these things we do make a difference in outcome."
There's more on radiation exposure from CT scans at the
http://www.radiologyinfo.org/en/info.cfm?pgbodyct American College of Radiology.
SOURCES: Fred A. Mettler Jr., M.D., U.S. representative to the United Nations Scientific Committee on the Effects of Atomic Radiation, and professor, radiology, University of New Mexico, Albuquerque; Robert Zimmerman, M.D., executive vice chair, radiology, Weill Cornell Medical Center, New York City; November 2009 Radiology
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Cell Phone May Reduce Bone Density in Hips
Published: Tuesday, October 27, 2009 | 6:15 AM ET
Turkish researchers used dual X-ray absorptiometry to measure bone density at the upper rims of the pelvis (iliac wings) in 150 men who carried their cell phones on their belts. The men carried their phones for an average of 15 hours a day, and had used cell phones for an average of six years.
Bone density was slightly reduced on the side of the pelvis where the men carried their cell phones, the study found. The difference wasn't statistically significant and didn't approach bone level density reductions seen in people with osteoporosis. However, the men were relatively young (average age 32), and further bone weakening may occur, said Dr. Tolga Atay and colleagues at Suleyman Demirel University in Isparta.
The study, published in the September issue of the Journal of Craniofacial Surgery, suggests that electromagnetic fields emitted by cell phones may have a harmful effect on bone density.
However, the researchers emphasized that their findings are preliminary and noted that future generations of cell phones may reduce users' exposure to electromagnetic fields. In the meantime, it "would be better to keep mobile phones as far as possible from our body during our daily lives," Atay and colleagues concluded.
The iliac wings of the pelvis are widely used for bone grafting, which means any reduction in bone density there may affect reconstructive surgery. In procedures where bone density is important for good outcomes, surgeons may want to consider the possible effects of exposure to electromagnetic fields from cell phones, the researchers suggested.
The World Health Organization has more about
http://www.who.int/peh-emf/about/WhatisEMF/en/ electromagnetic fields.
SOURCE: Journal of Craniofacial Surgery, news release, Oct. 23, 2009
Copyright 2009 ScoutNews, LLC. All rights reserved.
Los Angeles Times
More safety studies on cellphones are forthcoming, and manufacturers are working on lowering the levels of radiation emitted by phones. ...
Letters to the Formby Times: 28/10/09
Wireless net connection is a worry
I would like to express my concern that Woodlands Primary School in Formby is installing the wireless internet.
My two grandchildren attend this school.
I am all for progress but after recently moving to Southport I installed the internet wireless. I was using it for approximately 20 minutes and I found my head throbbing violently. I do suffer with high blood pressure and thought perhaps it was that. I called my son into the lounge and asked him how he felt.
He said his head felt weird as though his hair was standing on end. So I told him how I felt.
I disconnected from the wireless internet and plugged the wire connection back into my laptop.
The feeling in my head went and my son could no longer feel anything. How strange!
Then my daughter tells me that Woodlands Primary are having this installed over this half term. I am horrified to find only a small number of parents have objected to this.
As we do not know the full affects of this on our childrens health. Where do we go from here ?
VERY CONCERNED GRANDPARENT
I FULLY support the campaign against WiFi in Woodlands Primary School.
The former UK Health Protection Agency Chairman, Sir William Stewart, voiced concerns about WiFi.
Mobile phones and phone masts and demonstrations against Wi-Fi in other countries worldwide have tagged: EM radiation as a health hazard.
In April, a European Parliament resolution on the health concerns associated with electro-magnetic fields was adopted by 559 MEP votes in favour, 22 against and 8 abstentions. The report recognises that mobile phones, Wi-Fi, WiMAX, Bluetooth and DECT cordless telephones emits EMFs that may have adverse effects on human health.
The MEPs said: "The limits on exposure to electromagnetic fields (EMFs) which have been set for the general public are obsolete."
I am currently helping to organise an International EMF Conference in Stavanger, Norway, 17th November, 2009. Scientists and an advisory group are also attending a meeting for a week to discuss new biologically-based safety standards for human exposure.
Please go to the Radiation Research Trust website for details about the conference and review the research, political information and legal cases: www.radiationresearch.org