One of the most abundant substances in the cloud of radioactive steam released by a failing nuclear power plant is iodine-131 — a radioactive form of the element iodine that is found throughout nature. Iodine-131 poses a special health risk because of its cancer-causing effect on the thyroid gland.
The small, butterfly-shaped thyroid sits just below the voice box. From this perch, it controls how fast every cell in the body changes food into energy. The gland’s main product, thyroid hormone, governs the function of the digestive tract, brain, heart, nerves, muscles, bones, skin, and more.
Iodine is a key ingredient that goes into making thyroid hormone. We get this element from ocean-caught or ocean-farmed fish and shellfish, milk, cheese, yogurt, eggs, and fruits and vegetables grown in iodine-rich soil.
The human body is surprisingly good at absorbing iodine and storing it in the thyroid gland. That’s a problem when iodine-131 is released into the atmosphere. The thyroid stores it as readily as natural, non-radioactive iodine. As iodine-131 builds up in the thyroid gland, it emits bursts of radiation that can damage DNA and other genetic material. Such damage can remove the normal limits to cell growth and division. Unchecked growth of thyroid tissue is thyroid cancer.
Iodine-131 gets into the body several ways. A person can breathe in radioactive steam released by a nuclear power plant. Fallout — radioactive particles that fall out of the atmosphere and settle onto plants, soil, and water — further adds to the burden when a person eats iodine-131 enriched fruits and vegetables or drinks water containing the isotope. Milk is another vehicle — cows that eat grass sprinkled with iodine-131 make milk that contains it. Read more »
*This blog post was originally published at Harvard Health Blog*
Abdominal pain is the bane of many emergency physicians. Recently, I wrote how CT scans are on the rise in the ER. Much of those scans look for potential causes of abdominal pain.
In an essay from Time, Dr. Zachary Meisel discusses why abdominal pain, in his words, is the doctor’s “booby prize.” And when you consider that there are 7 million visits annually by people who report abdominal pain, that’s a lot of proverbial prizes.
One reason is the myriad of causes that lead bring a patient to the hospital clutching his abdomen. It can range from something as relatively benign as viral gastroenteritis where a patient be safely discharged home, to any number of “acute” abdominal problems necessitating surgery.
But more importantly, we need to consider how limited doctors actually are in the ER. Consider the ubiquitous CT scan, which is being ordered with increasing regularity:
The pros: CT scans are readily available, able to look at every organ in the abdomen and pelvis, and very good for ruling out many of the immediately life-threatening causes of belly pain. CT scans can also reduce the need for exploratory surgery. The cons: Often, CTs can’t diagnose the actual cause of ER patients’ abdominal pain. Worse, CTs deliver significant doses of radiation to a patient’s abdomen and pelvis (equivalent to between 100 and 250 chest X-rays). Over a lifetime, patients who receive two or three abdominal CT scans are exposed to more radiation than many Hiroshima survivors.
Add that to the fact that patients expect a definitive diagnosis when visiting the hospital — one that doctors can’t always give when it comes to abdominal pain. Read more »
*This blog post was originally published at KevinMD.com*
Emergency patients with acute abdominal pain feel more confident about medical diagnoses when a doctor has ordered a computed tomography (CT) scan, and nearly three-quarters of patients underestimate the radiation risk posed by this test, reports the Annals of Emergency Medicine.
“Patients with abdominal pain are four times more confident in an exam that includes imaging than in an exam that has no testing,” said the paper’s lead author. “Most of the patients in our study had little understanding of the amount of radiation delivered by one CT scan, never mind several over the course of a lifetime. Many of the patients did not recall earlier CT scans, even though they were listed in electronic medical records.”
Researchers surveyed 1,168 patients with non-traumatic abdominal pain. Confidence in medical evaluations with increasing levels of laboratory testing and imaging was rated on a 100-point scale. Then, to assess cancer risk knowledge, participants rated their agreement with these factual statements: “Approximately two to three abdominal CTs give the same radiation exposure as experienced by Hiroshima survivors,” and “Two to three abdominal CTs over a person’s lifetime can increase cancer risk.” Read more »
*This blog post was originally published at ACP Internist*