Ionizing radiation acute

Acute biological effects of the Chernobyl accident on local natural resources were documented by Sokolov et al. (1990). They concluded that the most sensitive ecosystems affected at Chernobyl were the soil fauna and pine forest communities and that the bulk of the terrestrial vertebrate community was not adversely affected by released ionizing radiation. Pine forests seemed to be the most sensitive ecosystem. One stand of 400 ha of Pirns silvestris died and probably received a dose of 80 to 100 Gy other stands experienced heavy mortality of 10- to 12-year-old trees and up to 95% necrotization of young shoots. These pines received an estimated dose of 8 to 10 Gy. Abnormal top shoots developed in some Pirns, and these probably received 3 to 4 Gy. In contrast, leafed trees such as birch, oak, and aspen in the Chernobyl Atomic Power Station zone survived undamaged, probably because they are about 10 times more radioresistant than pines. There was no increase in the mutation rate of the spiderwort, (Arabidopsis thaliana) a radiosensitive plant, suggesting that the dose rate was less than 0.05 Gy/h in the Chernobyl locale. 

O Farrell, T.P. 1969. Effects of acute ionizing radiation in selected Pacific northwest rodents. Pages 157-165 in D.J. Nelson and F.C. Evans (eds.). Symposium on Radioecology. Proceedings of the Second National Symposium. Avadable as CONF-670503 from The Clearinghouse for Federal Scientific and Technical Information, Natl. Bur. Standards, Springfield, VA 22151. 

High acute doses of ionizing radiation produce adverse biological effects at every organizational level molecular, cellular, tissue-organ, whole animal, population, community, and ecosystem (ICRP 1977 Whicker and Schultz 1982b LWV 1985 Hobbs and McClellan 1986 UNSCEAR 1988 Kiefer 1990 Severn and Bar 1991). Typical adverse effects of ionizing radiation include ... 

Radiation illness An acute organic disorder that follows exposure to relatively severe doses of ionizing radiation. It is characterized by nausea, vomiting, diarrhea, blood cell changes, and in later stages, hemorrhage and loss of hair. 

Dose In the context of chemicals, the temi dose means the amount, quantity, or portion of the chemical exposed to or applied to the target (e.g., a human being). It may also refer to a consistent measure used in toxicological testing to determine acute and chronic toxicities. An alternate definition is die amount of ionizing radiation energy absorbed per unit mass of irradiated material at a specific location, such as a part of die human body, measured in REMS, or an inanimate body, measured in rads. 

Gastrointestinal Syndrome Illness resulting from acute exposure to a chemical or ionizing radiation, resulting in damage to the gastrointestinal tract. 

---