Radiation, retardation and the developing brain: time is the crucial variable

Background: Widespread radiation is a threat unique to the modern world. A recent report reveals that sub‐clinical damage to human foetuses between 8 and 25 weeks of gestation can result in cognitive deficits still manifest 16–18 years after birth. These previously unrecognised, long‐term effects are apparently produced by a relatively short pulse of exposure to radioactive fallout at levels that were previously thought not to be deleterious. This idea is plausible given the nature of the developmental events occurring in the brain during this period of gestation. Conclusion: This exposed population should be examined for other neurological and psychiatric syndromes. If these findings are corroborated, in the event of future radiation exposures, steps should be taken to shield pregnant women who are within this window of vulnerability.