The phase-out of leaded petrol began in developed countries such as the United States in the 1980s, but in developing nations the additive, one of the world’s most serious pollutants blamed for increased blood pressure, cardiovascular disease, delayed mental and physical development, reduced attention span and increased criminality, was still being used until recently.

The California State University study cites the massive benefits the phase-out has brought, including more than 1.2 million fewer premature deaths annually, 125,000 of them of children, with tests showing lead in blood levels dropping dramatically by 90 per cent or more, particularly in cities.

Some 58 million crimes have been averted and IQs (intelligence quotient) have risen, with research indicating that children with lots of lead in their blood are much more likely to be aggressive, violent and delinquent. It is estimated that $2.4 trillion in costs have been saved each year, equivalent to 4 per cent of global gross domestic product (GDP).

The UN Environment Programme (UNEP), as an outcome of the 2002 World Summit on Sustainable Development, was entrusted with leading the final elimination of leaded petrol through a public-private partnership that helped most developing and transitional countries go unleaded.

The Partnership for Clean Fuels and Vehicles (PCFV), involving 120 civil society organizations, Governments and major oil and vehicles companies, has supported over 80 States to phase-out lead in transport fuel. The small handful of countries still using small amounts of leaded petrol – Afghanistan, Algeria, the Democratic People’s Republic of Korea (DPRK), Iraq, Myanmar and Yemen – are expected to make the switch over the next year or two.

The UN World Health Organization (WHO) estimates that between 15 and 18 million children in developing countries currently suffer from permanent brain damage due to lead poisoning and, according to the results of the research, leaded petrol was responsible for some 90 per cent of human lead exposure.

“Yet again, here is a clear body of analysis that demonstrates that far from being a burden on economies, acting on environmental challenges generates multiple Green Economy benefits right across countries and economies,” UNEP Executive Director Achim Steiner said of the study.

“Although this global effort has often flown below the radar of media and global leaders, it is clear that the elimination of leaded petrol is an immense achievement on par with the global elimination of major deadly diseases. This will go down in history as one of the major environmental achievements of the past few decades. It is a triumph of diplomacy and public-private collaboration.”

But although the lead phase-out has almost been completed, much more still needs to be done.

“Action is now underway to tackle other health hazardous vehicle emissions, such as the unacceptably high levels of sulphur still found in fuels on continents like Africa,” Mr. Steiner said.