Wilhelm Roentgen stumbled upon the potential of X-rays while tinkering with cathode instruments in 1895. The German physicist placed different objects in front of them to measure their reactions in front of a photographic plate that can record images.
Roentgen wanted to know what his wife's hand would look like when exposed to the mysterious rays. Lo and behold, the plate produced an image of her bones and flesh, much like what we see today in medical X-rays. The ability to create images within the human body was revolutionary, Nobel Prize-worthy work.
Today, X-rays are used in a variety of places, ranging from dentist and doctors' offices to safety checkpoints at airports. Although the medical scans help doctors and patients around the world monitor injuries and conditions, they also have a downside: radiation.
As we'll discuss, X-rays emit a type of radiation that can be harmful to humans if the intensity is too high or the exposure is too frequent. In this article, we'll explore the risks and benefits of using this tool to reveal valuable information about ourselves and the universe.
But first, we'll look at the dual personality of X-rays and why they can be both helpful and harmful. Read on to find out more.
X-rays: Helpful and Harmful
It's best to think of X-rays for what they are: a type of electromagnetic energy. These rays have short wavelengths, allowing them to carry a lot of energy. Yet when one considers what happens when they intercept the human body, the term ionizing radiation enters the equation.
Ionizing radiation can knock off electrons that orbit the nuclei of atoms -- sort of like if something knocked Earth from its orbit around the sun. When electrons become displaced, they create charged molecules, or atoms called ions, which can scatter and disrupt other atoms in our cells.
Cell damage from radiation can alter our DNA as well, increasing the chances of our cells mutating during replication or even turning cancerous with time. This is why doctors use only the effective dose of X-rays, or the lowest amount to get the job done during medical imaging. What's more, the radiation adds up over time, so frequency matters, too.
X-rays aren't all doom and gloom, though. Thankfully, our cells heal themselves after brief encounters. In medical contexts, X-rays provide a glimpse of bones, teeth and internal organs not visible from outside the body. They help assess breaks, fractures and abnormal growth in bones and allow doctors to track the effectiveness of surgeries. Ultimately, the benefits of receiving proper medical treatment often outweigh the risks of radiation.
It's also true that X-rays clue us in to the strange things our children and pets accidentally swallow. Next, learn which group has the largest vulnerability to X-ray radiation.
Children are More Vulnerable
Brief exposure to ionizing radiation isn't as worrisome in adults because mature cells can quickly repair themselves (for the most part), but babies' and children's bones and tissues are more at risk. Kids' cells divide more rapidly as they grow, creating more opportunities for mutations and DNA damage to be replicated. Pregnant women should tell their doctors they're with child before having any X-rays. And even though most medical scans avoid exposing fetuses to radiation, it's important to talk things over with a doctor to be sure.
Also, because the effects of radiation on the body accumulate with time, doctors reserve the use of X-rays on young patients for times when an immediate health concern outweighs the long-term risk -- much like what's done for adults [source: U.S. Food and Drug Administration]. This vulnerability leaves children at a greater risk of developing cancer and other health problems later in life.
Next time you're due for medical tests, it might be a good idea to ask a few questions. Find out what's appropriate to ask on the following page.
Exposure is Preventable
Sure, X-ray radiation has its dark side, but there's plenty you can do to reduce your exposure.
First, you should understand that scientists have created ways to minimize exposure to X-ray radiation. This mostly includes offering recommendations, measuring the entrance skin doses -- the amount of rays absorbed through the skin -- of certain procedures, ensuring equipment is working properly and providing the best training to people operating the machines. In general, the FDA regulates the production of X-ray equipment, while states make laws to oversee the technology's use [source: U.S. Environmental Protection Agency].
To ensure you're not being unnecessarily exposed, check the instruction and certification level of the technicians and doctors performing medical X-rays. Since training varies, you'll want to seek professionals with more education and experience. For instance, you might want to find clinics with board-certified radiologists for more serious scans. Don't be afraid to ask your doctor why an X-ray is or isn't necessary.
Can you be exposed to X-ray radiation outside the doctor's office? Find out on the next page.
X-Ray Radiation in Airports
We've learned that medical X-rays give doctors a unique glimpse into the flesh and bone beneath your skin, but how else are they used?
In recent years, the U.S. Transportation Security Administration has used X-ray body scanners to detect weapons and other potentially dangerous objects that can't be picked up by metal detectors. This certainly beefs up security for passengers before boarding an airplane, but it also exposes them to X-ray radiation. The use of these backscatter scanners has caused controversy, but is still common in many U.S. airports. Generally speaking, though, the amount of radiation is small compared to typical medical scans. For perspective, the average amount of radiation people are exposed to from these scanners equates to two minutes of being airborne on a plane while at its normal altitude -- a place that lacks the atmosphere's protection from incoming radiation [source: TSA].
Still, frequent flyers as well as airplane personnel should be more cautious about using scanners too often.
Did you know X-ray radiation isn't just limited to our world? Keep reading to learn about its use in science.
It Tells Us Cool Stuff
X-ray radiation's use in astronomy gives us plenty of cool information about the universe.
Many events in space, ranging from black holes to comets and stars, give off unique radiation signatures. Although we generally clump all X-rays together, the ones coming from space are a bit different. They're created from natural phenomena in the universe that give off immense amounts of energy (and heat).
To measure X-ray radiation, or the energy from particles in space, scientists collect information using satellites outside Earth's atmosphere. Such X-rays give us clues to the origins of the universe and contribute to our perceptions of auroras that routinely line the night sky.
Back on Earth, scientists create X-rays with particle accelerators, which move electrons near the speed of light around a track until they emit beams of the radiation. This allows researchers to examine the atomic structure of materials -- both synthetic and environmental.
Want to learn more about X-ray radiation? Peruse the next page for more interesting sources.
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