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What's caused all the fuss? Well, the World Bank report argues that the drive for biofuels by American and European governments has pushed up food prices by 75%. That is in stark contrast with the White House's claims that using crops for fuel, rather than food, has only pushed prices up by 2-3%. All the other factors discussed - rising demand for food from China and India, back-to-back droughts in Australia - are, the report says, marginal:
Without the increase in biofuels, global wheat and maize stocks would not have declined appreciably and price increases due to other factors would have been moderate.
The implication of this report, then, is that crop-derived fuels have been the ultimate cause of food riots, starvation and high prices around the world. And it is not an anti-biofuels campaigner who arrived at that conclusion, but an internationally respected World Bank economist with three decades' experience in tracking commodity markets.
This is controversial stuff. It was certainly too controversial for the World Bank to publish when the report was completed back in April. One source told me the study had gone all the way up to Robert Zoellick, the head of the World Bank, but was not published because "it was too hot for the Bank to handle".
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http://blogs.guardian.co.uk/environment/2008/07/exclusive_the_biofuels_report.htmlEDIT
http://image.guardian.co.uk/sys-files/Environment/documents/2008/07/10/Biofuels.PDF