While the study took into account factors that can affect sperm quality, such as age, researchers were unable to control for socio-economic factors, smoking or weight, which have been shown to have a major impact.

BBC: French sperm count 'falls by a third'

In 1992 he became Russia's prime minister, and control of Gazprom was assumed by his deputy, Rem Vyakhirev, a chain-smoking Soviet-style bureaucrat, whose first name stood for Revolution, Engels, Marx.

FORBES: Energy Tsar

The countries that conferred in South Africa were all parties to the WHO's Framework Convention on Tobacco Control, the so-called global tobacco treaty, which commits signatories to stop the promotion of smoking through advertising, and also to protect health policies from interference by the tobacco industry.

ECONOMIST: Smoking, governments and health