Where are the bodies? Ever since scientific concern over industrial chemicals in the environment escalated in the 1970s, alarms raised by public health advocates have been parried with a simple question by defenders of chemicals: If benzene, dioxins, vinyl chloride and the rest are so bad, why aren't bodies pilling in the streets? And relatedly: How can minuscule amounts of lead be neurotoxic when my kid breatehed lead his whole life and got into Princeton University? But understanding genes and genetic variatin just may answer these questins and more,through the emergingfield of environmental genomics. The better-known