Jeff Miner Consulting

(The report below was published Saturday, December 24, 2005 in The Sacramento Bee.

Limiting X-ray exposure

Medical X-ray toxicity is a hot topic among scientists. Assemblywoman Jenny Oropeza hopes her legislation can reduce unnecessary radiation for patients.

By Edie Lau -- Bee Science Writer

One in a series of reports on new laws that take effect in the new year.

Her bout with cancer last year caused Assemblywoman Jenny Oropeza to think about the many things that damage cells in the body. Her exploration led her to something that many people think of as strictly helpful, not harmful, to their health: medical X-rays.

"Virtually everybody gets X-rays," Oropeza said. "And you know, we don't really give it a thought."

As a California lawmaker, Oropeza is in a position to try to change that. The Long Beach Democrat has taken what she hopes is a first step with the passage this year of Assembly Bill 929, the California Radiation Exposure Information Act.

The law, which takes effect Jan. 1, requires the state Department of Health Services to develop mandatory quality-assurance standards for all radiological equipment in California to ensure the lowest possible dose of radiation without sacrificing image quality.

The issue of medical X-ray toxicity was a hot topic in science circles in 2005. Early in the year, the National Toxicology Program - a part of the National Institute on Environmental Health Sciences - announced it had added X-radiation and gamma radiation to the nation's official list of known human carcinogens.

In June, the National Research Council completed a five-year study of the biological effects of exposure to low levels of ionizing radiation.

The study found that even the smallest exposure is likely to cause a small increase in health risk to humans.

Oropeza and her staff in the Assembly looked into the subject. They discovered that while the state has quality-assurance guidelines for users of medical radiological equipment, abiding by the standards wasn't required.

The one exception is mammography. A 1992 federal law set mandatory standards for mammography involving credentialing of personnel and equipment maintenance.

So, while the tools of mammography must be inspected annually, other radiological equipment is examined by the state much less frequently.

According to Kevin Reilly, deputy director of prevention services at the state health department, equipment used in hospitals is considered by state law to be the highest priority. It must be inspected once every three years.

Equipment considered "medium priority" must be inspected every 4 1/4 years. Dental equipment is in its own category. Sources of radiation used in dentistry must be screened for defects by mail at least once every five years on average. Half of the dental equipment must be physically inspected at least once every six years on average.

While scientists and lawmakers are paying more attention to the potential dark side of medical radiology, no one questions that the tools can and do save lives.

Charles Meyers will speak to that. Meyers had a computed tomography (CT) scan of his left foot on Tuesday after he fell off a ladder and ended up at Mercy General Hospital's emergency room with what he suspected was a broken heel.

It was the second CT scan he's had recently, and he didn't worry for a moment about the radiation exposure.

"Two years ago, I had a CT scan on my lungs," said Meyers, a former Sacramento resident who was back in town visiting a friend. "Without it, I wouldn't have known I had clots in my lungs. It was definitely a life-saving procedure."

Oropeza said her concern is not the procedures that are medically necessary. Her target is the stuff that's unnecessary.

An example, she said, are full-body CT scans. "It's really popular with your younger (to) middle-aged, upwardly mobile people. They view it as a preventive thing where they go in, they pay 1,000 bucks or something ... and put a full-body scan on them that's totally unnecessary," she said.

The same trend prompted the National Toxicology Program to look into the health effects of radiation, an act that led it to add X-rays and gamma rays to the list - now 58 items long - of known human carcinogens.

"People were beginning to use more and more of these CT scans, which are equivalent to 100 to 400 X-rays at one shot," said Christopher Portier, associate director of the National Toxicology Program. "... That might not be a risk-free exercise, and people need to be reminded of that."

Lorenza Clausen, a radiology technologist at Mercy General, said the public should understand that even medically necessary procedures can result in significant exposure to radiation, too - exposure that she said can be reduced with training of medical personnel.

The use of fluoroscopy is an example. A form of real-time imaging that involves radiation, fluoroscopy is used increasingly in the treatment of heart problems, Clausen said. The imaging can enable a doctor to relieve blockage by inserting a stent into the clogged artery, thereby avoiding open-heart surgery.

Avoiding open-heart surgery is a good thing, of course, but the fluoroscopy is not benign, Clausen said. And a less-skilled physician might unwittingly expose a patient - along with everyone else in the room - to more radiation than is necessary.

"I've heard of (exposures) of 20 and 40 minutes at a time," she said. "That's a lot."

Reilly at the state health department said it's not clear whether rules that result from the new law will require that patient exposures are measured. The department is drafting regulations, which will be aired for public comment before going into effect by January 2008.

Oropeza said she is mindful of the need for individuals to keep better track of their medical radiation exposures. She considered legislation to require that radiation records be kept for patients, similar to vaccination records, but said the logistics were too complicated to work out during the legislative session. Oropeza may resurrect the idea.

"We're going to look at other ways of educating people to be more aware about especially unnecessary exposure," she said.

NEW LAW AT A GLANCE

Assembly Bill 929, the California Radiation Exposure Information Act, requires the state Department of Health Services to develop mandatory quality-assurance standards for all radiological equipment in California to ensure the lowest possible dose of radiation.

About the writer:

• The Bee's Edie Lau can be reached at (916) 321-1098 or elau@sacbee.com