In my opinion, after cigarettes, the second leading avoidable cause of cancer is nitrites added to processed meats. This substance has been much associated with brain cancer, especially in children and various other digestive cancers in the population at large. I am astounded that  this substance is even permitted. When nitrites are heated during cooking, substances found in meats called amines react with the nitrite to produce nitrosamines, especially powerful carcinogens. Nitrosamines for example, are found in chewing tobacco as well as other tobacco products, and I don’t have to tell you about the death toll from tobacco products.Even very low risk chemicals have been banned by the FDA. DDT for example, is actually very harmless to humans, it only affects insects trying to make their exoskeletons. It does seem to have bad effects on certain predatory birds, by interfering with calcium metabolism and the production of eggshells. The answer to this is to limit the use of DDT to either indoors or small amounts around human habitations, especially using it on mosquito netting in tropical countries. In the past, millions of tons of DDT were carelessly used from cropdusting planes. Now we go to the other extreme. It is actually one of the safest and most effective of all insecticides. The banning of DDT has now caused not only a horrible epidemic of bed bugs (it is extremely effective against these noxious pests, there is actually no good substitute) but has led to the deaths of millions of children in third world countries from malaria and other mosquito borne diseases. Cyclamate, an artificial sweetener, was banned many years ago because mice were given the equivalent of a human being drinking six bathtubs filled with diet soda per day, during what I consider to be an insane experiment. The mice showed a slight increase in bladder cancer. I’m amazed that anything given in such stupendous amounts would be anything but immediately fatal. Obviously cyclamates are extremely safe compared to many other things. A couple of tablespoons of salt in fact,will kill you if you do not manage to throw up this potentially toxic chemical when taken to excess.