FALLOUT CONTAMINATION OF FOOD AND WATER Protection of the civilian population in wartime from external exposure to gamma radiation has received much more attention than protection against contamination in food and water. External exposure is far more dangerous not only in early effects -- lethality and acute radiation sickness -- but probably in the longer-term effects -- reduction of life expectancy, increased malignancies, and genetic consequences. During a nuclear war, early deaths due to the ingestion of contaminated food and water are highly improbable. The effects to be expected if fallout radionuclides gain entry to the body, are of the type that would be seen years afterward. Most of the external gamma radiation expo- sure would occur ina short period -- during hours to days after the attack, while the internal exposures could occur over a prolonged period ~- in the case of strontium-90, years to perhaps a few decades. iodine is the exception. Radio- Because of the short half-life of the important iodine isotopes (about 8 days for 3} the radioiodine exposure would occur in the first days to weeks, might not be seen for years. Results of the exposure, however,