Ionizing Radiation

To understand the biological effects of radiation one must first understand the basics of radiation. Electromagnetic radiation consists of waves of electric and magnetic energy moving together – radiating - through space at the speed of light. In general, two things can happen when radiation is absorbed by matter: ionization or excitation.
• Ionization occurs when the radiation carries enough energy to remove an electron from an atom or molecule. This is ionizing radiation.
• Excitation occurs when the radiation carries only enough energy to excite the motion of the atoms or molecules. This is non-ionizing radiation. Non-ionizing radiation includes RF radiation and microwave radiation and covers concerns related to cell phone radiation. (This database features a section on non-ionizing radiation.)
Types of ionizing radiation include ultraviolet light, X-rays, gamma rays, and all particle radiation from radioactive decay. Ionizing radiation has many beneficial applications, including uses in medicine, industry, agriculture, and research. However, as the use of ionizing radiation increases, so does the potential for health hazards if it is not properly used or contained.

Background

People are exposed to natural radiation sources as well as human-made sources every day. Natural radiation comes from many sources including more than 60 naturally-occurring radioactive materials found in soil, water, and air. Radon, a naturally-occurring gas, emanates from rock and soil and is the main source of natural radiation. Radon gas from natural sources can accumulate in buildings, especially in confined areas such as attics or basements. Epidemiological evidence shows a clear link between high concentrations of radon and lung cancer.
People are also exposed to natural radiation from cosmic rays, particularly when an individual is at high altitude, such as when traveling in an airplane. On average, 80% of the annual dose of background radiation a person receives is due to naturally occurring terrestrial and cosmic radiation sources. Background radiation levels vary geographically due to geological differences. Exposure in certain areas can be more than 200 times higher than the global average. Areas with hot springs, for example, have much higher levels of natural background radiation.
Human exposure to radiation also comes from man-made sources ranging from nuclear power generation to medical uses of radiation for diagnosis or treatment. Today, the most common human-made sources of ionizing radiation are medical devices, including X-ray machines.

Injuries and Damages

In general, ionizing radiation is harmful and potentially lethal to living beings, though the true health effects from ionizing radiation depend greatly on the dose of radiation absorbed. Ionizing radiation weakens and breaks up DNA, either by damaging cells enough to kill them or causing them to mutate in ways that may eventually lead to cancer. Radiation impairs the functions of tissues and organs. Chronic exposure can cause tumors, cataracts, and potentially harmful genetic changes. Most of the health concerns surrounding ionizing radiation are related to cancer.
Exposure to ionizing radiation is known to increase the future incidence of cancer, particularly leukemia. The mechanism by which this occurs is understood and accepted, but quantitative models predicting the level of risk remain controversial. Most researchers accept that natural background radiation is the most hazardous source of radiation to general public health, followed closely by medical imaging.
Radiation can also produce acute effects such as skin redness, hair loss, skin burns, or Acute Radiation Syndrome (ARS). ARS, also called radiation toxicity or radiation sickness), is a rare illness caused by irradiation of the entire body by a high dose of penetrating radiation in a very short period of time, usually minutes. Examples of people who suffered from ARS are the survivors of the Hiroshima and Nagasaki atomic bombs or the firefighters that first responded after the Chernobyl Nuclear Power Plant event in 1986.

Ultraviolet Radiation Risks

Ultraviolet (UV) radiation is part of the electromagnetic spectrum emitted by the sun. UV rays induce the production of vitamin D in the skin. Vitamin D helps to regulate calcium metabolism, immunity, cell proliferation, insulin secretion, and blood pressure. People with higher levels of vitamin D tend to have lower rates of diabetes, heart disease, and stroke. However, prolonged human exposure to solar ultraviolet (UV) radiation may result in acute or chronic health effects on the skin, eyes, and immune system. Suntan, sun burn, and freckling are familiar effects of over-exposure to UV rays. Overexposure greatly increases the risk of skin cancer. Besides sunlight, tanning lamps and beds are known sources of UV rays.

X-Ray Radiation Risks

X-ray examinations provide valuable information about an individual’s health and assist doctors in making accurate diagnoses, but there has been concern about whether certain medical imaging scans, such as X-rays and CT scans, cause cancer. The scientific unit of measurement for radiation dose, commonly referred to as effective dose, is the millisievert (mSv). A single chest x-ray exposes a patient to about 0.1 mSv, which is about the radiation dose people are exposed to naturally over the course of about 10 days. A mammogram exposes a woman to 0.4 mSv, which is about the amount a person would expect to get naturally in about 7 weeks. Studies published by teams from Columbia University and the National Cancer Institute predicted that up to 2% of future cancers – about 29,000 cases and 15,000 deaths annually – might be caused by CT scans. The lifetime risk the general population has of dying of cancer, regardless of X-ray or CT scan usage, is 1 in 5.
While X-Rays and CT scans are essential diagnostic tools, the Food and Drug Administration reports that 30% to 50% of ordered imaging tests are medically unnecessary. While the effects of a single scan would be negligible, many Americans undergo multiple tests. A 2009 study by researchers at Brigham and Women’s Hospital in Boston found that among 31,000 patients who had a diagnostic CT scan in 2007, 33% had more than 5 during their lifetime, 5% received 22 or more and 1% underwent more than 38 scans.

Legislation and Regulation

Regulations concerning ionizing radiation are generally specific to a certain type of ionizing radiation risk. For example, the federal government has issued regulations to protect against ionizing radiation resulting from activities conducted under licenses issued by the Nuclear Regulatory Commission.
OSHA has provided exposure guidelines for ionizing radiation in the workplace at 29 CFR § 1910.97. The agency defines radiation as including: “alpha rays, beta rays, gamma rays, X-rays, neutrons, high-speed electrons, high-speed protons, and other atomic particles; but such term does not include sound or radio waves, or visible light, or infrared or ultraviolet light.” The OSHA standards apply to all forms of radiation, including intermittent or continuous, and whether affecting only parts of the human body or the entire person. Most possible sources of radiation are subject to the standards, including radiation found in communications, science and industry and radio-based navigation. Not included in the standard is the purposeful exposure of patients to radiation under the direction of physicians, such as the use of magnetic resonance imaging (MRI) for diagnostics.
Many states have developed their own OSHA standards. Generally, these standards may be more stringent -- but not less stringent -- than the federal OSHA standards. The siting of facilities for providing personal wireless services are dealt with differently, being primarily governed by FCC regulations.

Liability and Insurance

Governmental and media attention to possible damage from ionizing radiation continues to increase, meaning that providers and manufacturers of equipment that uses ionizing radiation should anticipate more litigation and pay close attention to insurance coverage for liability and bodily injury. Two areas that have caused significant concern are radiation exposures related to medical imaging and military service.

Medical Exposures

Some industry-watchers have suggested that the statistical long-term risk of cancer from medical imaging procedures is significant when one takes into account all the patients undergoing these procedures, and considers the life span of an individual patient. Liability lawsuits are likely to be negligence-based malpractice claims against providers and equipment manufacturers. Allegations may include operator error, equipment design defect or malfunction, medically unnecessary procedures, failure to warn, and more. The most compelling defense against legal claims would probably involve an analysis of the risk of the procedure versus the benefit. If the clinical need for a medical scan is questionable, such as an individual with no symptoms who self-refers for a whole-body scan, liability becomes a more difficult issue. The use of equipment that produce ionizing radiation, the techniques, rules, paperwork, the content of patient communications and more must be examined against the available insurance coverages.

Military Exposures

The United States Veteran’s Administration (VA) has established that veterans who were exposed to ionizing radiation during their service and developed certain diseases, such as cancer, are eligible for disability compensation and health care without having to prove a causal connection. The VA also recognized that certain other diseases are possibly caused by exposure to ionizing radiation during military service; that list includes cancers, thyroid diseases, cataracts, brain or central nervous system tumors and other conditions. The VA will decide these claims on a case by case basis.

Litigation

Radiation-related medical events that are likely to result in litigation can include incidents of inadequate staffing or training, software or hardware malfunctions, or failure to follow set procedures. Cancer patients receiving radiation therapy have been injured by faulty calculations of the number or dosage of radiation treatments, poor documentation of therapy sessions, application of radiation to the wrong part of the body, or unnoticed equipment malfunctions. As treatment methods involving ionizing radiation continue to evolve, so will the opportunity for lawsuits.

Future Outlook

While humans cannot control the levels of ionizing radiation that occurs naturally in our environments, we can control what man-made forms of ionizing radiation we expose ourselves to. X-ray and CT scans are crucial medical tools, but doctors should be wary of using them excessively. The use of alternative medical imaging, such as MRI, has grown significantly in the past decade and will continue to develop in the years to come. These scans may someday replace X-rays and CT scans that expose humans to heightened levels of radiation. Insurers benefit from staying informed about developments regarding the use of ionizing radiation in the medical field, as that is where ionizing radiation’s greatest threat lies.

In the News

2018

• Trump’s EPA moving to loosen radiation limits - ELLEN KNICKMEYER , AP (10/02/2018)
  The Trump administration is quietly moving to weaken U.S. radiation regulations, turning to scientific outliers who argue that a bit of radiation damage is actually good for you – like a little bit of sunlight. . . . The government’s current, decades-old guidance says that any exposure to harmful radiation is a cancer risk. And critics say the proposed change could lead to higher levels of exposure for workers at nuclear installations and oil and gas drilling sites, medical workers doing X-rays and CT scans, people living next to Superfund sites and any members of the public who one day might find themselves exposed to a radiation release. . . . The Trump administration already has targeted a range of other regulations on toxins and pollutants, including coal power plant emissions and car exhaust, that it sees as costly and burdensome for businesses. Supporters of the EPA’s new radiation guidance argue the government’s current no-tolerance rule for radiation damage forces unnecessary spending for handling exposure in accidents, at nuclear plants, in medical centers and at other sites.
• Workers' radiation exposure halts nuke plant demolition - Nicholas K. Geranios, AP (SFGate) (04/10/2018)
  Seven decades after making key portions of the atomic bomb dropped on Nagasaki, Japan, workers at the Hanford Nuclear Reservation are being exposed to radiation as they tear down buildings that helped create the nation's nuclear arsenal.
  Dozens of workers demolishing a plutonium processing plant from the 1940s have inhaled or ingested radioactive particles in the past year, and even carried some of that radiation into their vehicles, according to the U.S. Department of Energy.
  The incidents have prompted the federal government, along with state regulators, to halt the demolition of the sprawling Plutonium Finishing Plant until a safe plan can be developed.

2017

• GE sued for Fukushima disaster - Brian Dowling, Boston Herald (11/18/2017)
  Japanese property owners and businesses near the Fukushima nuclear plant that melted down after a devastating 2011 tsunami filed a $500 million class-action lawsuit against General Electric for negligently designing the doomed plant. . . . The lawsuit, filed yesterday in federal court in Boston, claims the explosions and release of radioactive material at the Fukushima reactors — likely the most costly industrial accident in history at $200 billion — were caused by GE’s unsafe design of the reactors and further efforts to cut costs that also undercut safety during the construction of the plant. . . . As a result, the area around Fukushima, according to the lawsuit, became a “ghost town.”
• Grasslands, Oakbridge residents want answers about radiation lawsuit - Suzie Schottelkotte, The Ledger (04/07/2017)
  
  Four weeks after a federal lawsuit was filed alleging elevated radiation levels in Lakeland's Oakbridge and Grasslands communities, a group of residents came together Friday seeking answers. The lawsuit, filed by a group of five law firms, accuses the Drummond Co. of building the two developments on reclaimed phosphate land that is contaminated with gamma radiation. The lawsuit states the gamma radiation levels are equal to getting a chest X-ray at least once a week.

2016

• Radiation and the cost of ignorance - T. Douglas Reilly, Santa Fe New Mexican (07/16/2016)
  A recent incident involved a radioactive americium source (Am-241) found in Santa Fe and transferred to Los Alamos National Laboratory. This cost $6 million (paid by the owner) and involved 40 people. The source was actually of no health or safety concern and could have been transported in a pickup by one or two people.

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