Overview
Radiation is energy that travels in waves or particles. People are exposed to small amounts every day from natural background sources, and some exposures also happen during medical care, work, travel, or accidents. Ionizing radiation, such as X-rays and gamma rays, can remove electrons from atoms and may injure tissues at high enough levels.
Key Symptoms
Symptoms depend on the dose and the body area exposed. Mild or moderate exposure may cause no immediate symptoms. Higher exposures can lead to nausea, vomiting, skin redness or burns, weakness, dizziness, hair loss, or changes in blood cell counts, while long-term effects can include cataracts, infertility, and increased cancer risk.
Causes and Risk Factors
Radiation exposure may come from sunlight, radon gas in buildings, medical imaging or radiation therapy, certain workplaces, industrial accidents, or nuclear events. Risk rises with higher dose, longer exposure time, repeated exposure, and being closer to the source. Risk also depends on age, pregnancy, and whether exposure involves the whole body or a small area.
Who Is Affected
Anyone can be exposed to radiation, but the level and type vary. Healthcare workers, industrial workers, airline crew, miners, emergency responders, and people living near contamination sites may have higher chances of significant exposure. Children and developing babies during pregnancy can be more sensitive to ionizing radiation.
Prevention
Prevention depends on the source. For ionizing radiation, common safety principles are limiting time near the source, increasing distance, and using shielding or protective controls. Follow workplace safety rules, ask healthcare professionals why an imaging test is needed, avoid unnecessary scans, test homes for radon where recommended, and follow public health instructions during radiation emergencies.
Diagnosis and Tests
Evaluation starts with learning what the source was, when the exposure happened, how long it lasted, and what symptoms are present. Healthcare professionals may use a physical exam, blood tests, skin assessment, and information from radiation monitors or contamination checks. In some situations, specialists in radiation medicine, toxicology, or public health may be involved.
Treatment Categories
Treatment depends on the type and amount of exposure. Care may include removing contaminated clothing, washing exposed skin, treating burns or injuries, monitoring blood counts, and supportive hospital care for serious exposure. Some emergencies require specialized public health or hospital treatment directed by radiation experts.
When to Seek Medical Care
Seek medical care if you think you were exposed to a significant radiation source at work, during an accident, or after a public emergency. Also get medical advice for skin burns after a known exposure, unexplained nausea or vomiting after a radiation incident, or concerns during pregnancy. If exposure happened during medical imaging, speak with the ordering clinician if you have questions about risks and alternatives.
When It May Be an Emergency
Get urgent help right away after a known or suspected large exposure, especially after an industrial accident, damaged radiation equipment, or a nuclear or radiological event. Emergency warning signs include vomiting soon after exposure, burns, trouble breathing, severe weakness, confusion, loss of consciousness, or exposure together with other serious injuries. Follow local emergency instructions about sheltering, evacuation, decontamination, and where to go for evaluation.