The document discusses the potential health effects of radiation exposure from the Fukushima Daiichi nuclear power plant crisis. It explains that ionizing radiation can break chemical bonds and cause cancer if exposure levels are high enough. Initial symptoms of radiation sickness include nausea, fatigue and vomiting, while very high exposure leads to organ damage, loss of consciousness and death. Certain radioactive isotopes like Cesium-137 and Iodine-131 are especially dangerous if ingested due to accumulation in soft tissues and the thyroid gland. The document provides exposure levels in microsieverts that correspond to different health effects ranging from mild sickness to death.