Scientists claim ordinary folks can’t be trusted to weigh the pros and cons of transgenics – swapping genes from one species to another. They know nothing about genetics (too overwhelmed by the “yuck factor”) and even less about risk assessment (numbers are hard). The problem, Denise Caruso argues in Intervention, is that scientists don’t know much about them, either.

Caruso isn’t some wild-eyed anti-science protestor. A former columnist forThe New York Times, she specializes in how new technology reaches the market. In Intervention, she examines how haphazardly transgenic organisms are being developed and have already been unleashed into the environment. A freely admitted generalist, her surprisingly approachable book is not a stats lesson on risk analysis, or a genetics primer. Instead, she asks what criteria scientists, regulators, and businesses use to make their decisions. What she finds is that the benefits of transgenics are almost an article of faith, with surprisingly little scientific or economic research to back it up. As she quotes Craig Venter, former president of Celera Genomics and a member of the human genome project, “My view of biology is, we don’t know shit.”

Using peer-reviewed studies, Caruso devastates two core myths of the transgenic industry: that deliberately inserting genetic material from one species into another is the same as crossbreeding two strains of the same species and that all scientific testing is equal. Science draws its conclusions from the evidence it has at hand, leaving no room for ambiguity. Often, Caruso finds, successes are talked up, while negative results are written off as experimental error. This means the criteria for judging a product as safe are worryingly selective, and the ecological context is ignored.

For example, genetically engineered, herbicide-resistant Roundup Ready plants are “successful” because they produce 30% more crop, but this ignores that they cost 35% more to raise. Or that they encourage farmers to dump more toxins on their fields. Or that they may introduce herbicide-resistant genes into weeds, making the whole project pointless. And, for good or ill, once those lab-manipulated life-forms are out in the world, they’re almost impossible to stop. As Caruso chillingly explains, there’s no factory recall on genetics.