Acute radiation syndrome
Acute radiation syndrome results from high-dose ionizing radiation exposure.
Acute radiation syndrome (ARS), also known as radiation sickness or radiation poisoning, is a collection of health effects caused by exposure to high amounts of ionizing radiation in a short period of time. Symptoms can start within an hour and last for months, with early signs including nausea, vomiting, and loss of appetite. ARS involves a total dose greater than 0.7 Gy, generally from an external source delivered within minutes, and can result from nuclear reactors, cyclotrons, cancer therapy devices, nuclear weapons, or radiological weapons.
- field
- Radiology, Nuclear Medicine, Radiation Biology
- known_for
- Health effects of acute high-dose ionizing radiation exposure
- types
- Hematopoietic, gastrointestinal, neurovascular syndromes
- threshold_dose
- Greater than 0.7 Gy (70 rad)
- fatal_range
- Above 4 Gy (400 rad) without exotic treatment
Lore & Background
Acute radiation syndrome is classically divided into three main presentations: hematopoietic, gastrointestinal, and neurovascular. Hematopoietic syndrome involves a drop in blood cells, leading to infections, bleeding, and anemia, detectable at doses as low as 0.25 Gy. Gastrointestinal syndrome follows doses of 6–30 Gy, with nausea, vomiting, and abdominal pain; vomiting within 1–2 hours post-exposure is a marker for fatal doses above 4 Gy. Neurovascular syndrome occurs at doses greater than 30 Gy, presenting with dizziness, headache, or decreased consciousness within minutes to hours, and is almost always fatal.
Reader's Guide
Acute radiation syndrome is generally rare, but a single event can affect large numbers of people. The vast majority of cases, alongside blast effects, were inflicted by the atomic bombings of Hiroshima and Nagasaki, with post-attack deaths in the tens of thousands. The Chernobyl nuclear power plant disaster caused 134 cases and 28 deaths. Treatment is generally supportive care, including blood transfusions, antibiotics, colony-stimulating factors, or stem cell transplant. Short-term outcomes depend on dose exposure. ARS differs from chronic radiation syndrome, which occurs after prolonged low-dose exposure, and from radiation-induced cancer.
Did You Know?
- ARS involves a total dose greater than 0.7 Gy (70 rad), generally from an external source delivered within minutes.
- The neurovascular syndrome occurs at doses exceeding 50 Gy and is almost always fatal even with aggressive intensive care.
- A person less than 1 mile from the Hiroshima atomic bomb's hypocenter absorbed about 9.46 Gy of ionizing radiation.
- The Chernobyl disaster caused 134 cases of ARS and 28 deaths.
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