Gastrointestinal Syndrome occurs at what dose threshold?

Gastrointestinal Syndrome is primarily associated with high doses of ionizing radiation, particularly when the absorbed dose exceeds the threshold of 10 Gray (Gy). At this level, significant damage occurs to the rapidly dividing cells of the gastrointestinal tract, notably in the intestinal lining where the crypt cells are particularly sensitive to radiation.

When the dose reaches around 10 Gy, the ability for the gastrointestinal tract to regenerate is severely compromised, leading to symptoms such as nausea, vomiting, diarrhea, and, in severe cases, can lead to death. This syndrome highlights the critical role of radiation dose in the effectiveness and biological effects on human tissues, demonstrating the damaging impact radiation can have at elevated levels.