Le General Social Survey fournit des données sur une vaste étendue de sujets. Les répondants ont été interrogés sur leurs préoccupations environnementales. Comment mesurer l’intelligence des individus sondés ? Le GSS ne fournit évidemment pas de test de QI, mais un Wordsum test (score allant de 0 à 10). Bien que le Wordsum corrèle à 0.71 avec le test QI, il n’est malheureusement ni plus ni moins qu’une tranche d’un test QI : le Wordsum est “juste” un test de vocabulaire. Si le Wordsum n’est pas un excellent substitut pour le QI, il n’est pas médiocre non plus. L’échantillon porte sur les blancs (range : 1972-2010).
Les données ont été ajustées pour le niveau d’éducation.
1416. And for each of these statements, just check the box that comes closest to your opinion of how true it is. In your opinion, how true is this? e. All pesticides and chemicals used on food crops cause cancer in humans.
Leur opinion est proche de la vérité. Dan Gardner écrivait dans son livre “Risk: The Science and Politics of Fear” :
‘Exposure to pollutants in occupational, community, and other settings is thought to account for a relatively small percentage of cancer deaths,’ says the American Cancer Society in Cancer Facts and Figures, 2006. Of those, occupational exposures – workers in aluminum smelters, miners who dug asbestos under the unsafe conditions of the past – are by far the biggest category, responsible for perhaps four per cent of all cancer. The ACS estimates that only 2 per cent of all cancers are the result of exposure to ‘man-made and naturally occurring’ environmental pollutants – a massive category that includes everything from naturally occurring radon gas to industrial emissions to car exhaust. (page 269)
It’s critical to understand that not all carcinogenic chemicals in the environment are man-made. Far from it. To take just one example, countless plants produce carcinogenic chemicals as defences against insects and other predators and so our food is positively riddled with natural carcinogens. They are in coffee, carrots, celery, nuts, and a long, long list of other produce. Bruce Ames, a leading cancer scientist at the University of California at Berkeley, estimates that ‘of all dietary pesticides people eat, 99.99 per cent are natural’ and half of all chemicals tested – synthetic and natural – cause cancer in high-dose lab animal experiments. (page 270)
Major health organizations agree that traces of synthetic chemicals in the environment are not a large risk factor. What is hugely important is lifestyle. Smoking, drinking, diet, obesity, and exercise: These things make an enormous difference – by most estimates, accounting for 65 per cent of all cancers. (page 270)
‘You’re talking about studying humans and there are a million confounders. A study will say this and another will say the opposite’ … Ames cites the example of a controversy in California’s Contra Costa county. ‘There are a lot of refineries and there is more lung cancer. Ah, the refineries are causing the lung cancer. But who lives around refineries? Poor people. And who smokes more? Poor people. And when you correct for smoking, there’s no extra risk in the county.’ (page 275)
… cancer is primarily a disease of aging, a fact which has a profound effect on cancer statistics. The rate of cancer deaths in Florida, for example, is almost three times higher than in Alaska, which looks extremely important until you factor in Florida’s much older population. ‘When the cancer death rates for Florida and Alaska are age-adjusted,’ notes a report from the American Cancer Society, ‘they are almost identical.’ (page 281)