The issues surrounding G.M.O.s - genetically modified organisms - became more complicated last week when the International Agency for Research on Cancer declared that glyphosate, the active ingredient in the widely used herbicide Roundup, probably causes cancer in humans. Two insecticides, malathion and diazinon, were also classified as probable" carcinogens by the agency, a respected arm of the World Health Organization. Roundup, made by Monsanto for both home and commercial use, is crucial in the production of genetically engineered corn and soybean crops, so it was notable that the verdict on its dangers came nearly simultaneously with an announcement by the Food and Drug Administration that new breeds of genetically engineered potato and apple are safe to eat. Few people are surprised that an herbicide in widespread use is probably toxic at high doses or with prolonged exposure, circumstances that may be common among farmers and farmworkers. Nor is it surprising that it took so long - Roundup has been used since the 1970s - to discover its likely carcinogenic properties. There is a sad history of us acting as guinea pigs for the novel chemicals that industry develops. To date, G.M.O.s and other forms of biotech have done nothing but enrich their manufacturers and promote a system of agriculture that's neither sustainable nor for the most part beneficial. We don't need better, smarter chemicals along with crops that can tolerate them; we need fewer chemicals. There's no reason to put the general population, and particularly the farming population, at risk for the sake of industry profits.