BECAUSE STOPPING DDT USE DIDN'T KILL ENOUGH PEOPLE FOR THE LEFT:

In August, environmentalists in the Philippines vandalized a field of Golden Rice, an experimental grain whose genes had been modified to carry beta-carotene, a chemical precursor of vitamin A.

Golden Rice is not produced by a corporate behemoth but by the public sector. Its seeds will be handed out free to farmers. The aim is to improve the health of children in poor countries by reducing vitamin A deficiency, which contributes to hundreds of thousands of premature deaths and cases of blindness each year.

Environmentalists claim that these sorts of actions are justified because genetically modified (GM) crops pose health risks. Now the main ground for those claims has crumbled.

Last year a paper was published in a respected journal, Food and Chemical Toxicology. It found unusual rates of tumors and deaths in rats that had been fed upon a variety of maize resistant to a herbicide called Roundup, as a result of genetic modification by Monsanto, an American plant-science firm. Other studies found no such effects, but this one enabled campaigners to make a health-and-safety argument against GM crops--one persuasive enough to influence governments. After the study appeared, Russia suspended imports of the grain in question. Kenya banned all GM crops. And the French prime minister said that if the results were confirmed he would press for a Europe-wide ban on the GM maize.

But the methodology of the study, by Gilles-Eric Séralini of the University of Caen and colleagues, was widely criticized and, on November 28th, the journal retracted the paper (see "GM maize, health and the Séralini affair: Smelling a rat"). There is now no serious scientific evidence that GM crops do any harm to the health of human beings.

There is plenty of evidence, though, that they benefit the health of the planet. 

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