London: Exposure to nuclear radiation triggers an increase in male births, says a new study.
The research shows that radiation from atomic bomb testing before the Partial Test Ban Treaty in 1963, the Chernobyl accident in the then USSR, and from living near nuclear facilities, has had a long-term negative effect on the ratio of male-to-female human births.
Ionizing radiation from nuclear activity is known to have mutagenic properties and is therefore likely to cause men to father more sons than daughters, reports the journal Environmental Science and Pollution Research.
Hagen Scherb and Kristina Voigt from Helmholtz Zentrum, Munich, Germany, looked at the long-term effects of radiation exposure on sex odds (more male births) that may reveal differences in seemingly normal as well as adverse pregnancy outcomes between maternal and paternal exposure.
Scherb and Voigt conclude, "We find strong evidence of an enhanced impairment of humankind`s genetic pool by artificial ionizing radiation." Their analyses show a significant male-female gap in all three cases, according to a Helmholtz statement.
Increase in male births relative in Europe and the US between 1964-1975 are a likely consequence of the globally emitted and dispersed atmospheric atomic bomb test fallout, prior to the test ban, that affected large human population after a certain delay.
There was a significant jump of sex odds in Europe in 1987 following Chernobyl, whereas no such similar effect was seen in the US, which was less exposed to the consequences of the catastrophe.
Among populations living close to nuclear facilities (within 35 km), the sex odds also increased significantly in both Germany and Switzerland during the running period of those facilities.
The authors estimate that the deficit of births and the number of stillborn or impaired children after the global releases of ionizing radiation amount to several millions globally.