Chernobyl nuclear facility  (Source:
Researchers found that long-term nuclear radiation exposure led to either increased male births or decreased female births

Researchers from the Helmholtz Zentrum München have discovered that nuclear radiation exposure either causes a higher rate of male births or a decreased rate of female births.

There has been a lot of talk regarding nuclear radiation and its effects recently for obvious reasons. On March 11 of this year, a 9.0-magnitude earthquake struck Japan causing tsunamis and trouble for the Fukushima Daiichi nuclear plant, which recently suffered a nuclear meltdown.

This tragic event has caused world leaders to reevaluate the use of nuclear power. For instance, French President Nicolas Sarkozy called for a global nuclear review after visiting Japan, and U.S. senators demanded the Nuclear Regulatory Commission (NRC) to inspect the country's use of nuclear power.

On the other hand, nuclear power does have its benefits, such as clean, cheap and reliable power as an alternative energy source.

The advantages and disadvantages of nuclear power is a constant game of tug-o-war, but there's no argument that long-term nuclear radiation can have troubling effects on humans.

But in a new study led by Hagen Scherb and Kristina Voigt from the Helmholtz Zentrum München, exposure to nuclear radiation didn't necessarily have a harmful effect on humans, but rather an interesting impact on the gender of babies.

Scherb and Voigt studied those who live near nuclear facilities, as well as areas affected by radiation from the atomic bomb testing before the Partial Test Ban Treaty in 1963 and the Chernobyl nuclear disaster. What they found was that the ratio of male to female births was biased in favor of male births by a noticeable amount.

In fact, they found that there was an increase in male births over female births in the U.S. and Europe from 1964 to 1975, which occurred immediately after the globally dispersed atmospheric atomic bomb test fallout prior to the ban in 1963. They also found a heightened amount of male births over female births in Europe in 1987, one year after the Chernobyl disaster. The U.S., which was not affected by the nuclear disaster, did not experience the same shift in male-dominated births.

In addition, the study found that those living within 22 miles of nuclear facilities in Germany and Switzerland had an increased birth rate of male babies over female babies.

Researchers believe these results were caused by ionizing radiation from nuclear activity, which possesses mutagenic characteristics and can negatively affect reproduction. It is believed that nuclear radiation causes men to "father more sons while mothers give birth to more girls." The researchers looked at the amount of paternal and maternal exposure and concluded that it may have effects on sex odds, but they're not sure if it increased the number of male births or decreased the number of female births. They also looked at sex odds with respect to normal pregnancy and adverse pregnancy outcomes in regards to maternal exposure and paternal exposure.

"Our result contribute to disproving the established and prevailing belief that radiation-induced hereditary effects have yet to be detected in human populations," said the study's conclusion. "We find strong evidence of an enhanced impairment of humankind's genetic pool by artificial ionizing radiation."

This study was published in Environmental Science and Pollution Research.

