Many new orleanians breathed a sigh of relief recently when scientists at the Louisiana Water Resources Research Institute announced that tests of the city´s floodwaters showed them to be no more toxic than your average stormwater. Sure, they said, lead and arsenic levels exceed drinking-water standards, but the levels are typical of rainwater on city streets after a hard storm. Phew, right? Well, maybe not. Several environmental groups-foremost among them the Natural Resources Defense Council-just announced the results of a few tests of their own. New Orleans, they report, is covered with such high levels of toxins, including arsenic and DDT, that families with children shouldn´t return to the city until it´s cleaned. The Environmental Protection Agency even recommends the use of protective gloves when handling floodwater sediment. But toxicologist Tom Harris of the Louisiana Department of Environmental Quality has said that the standards showing potential risks are based on children being exposed to the dirt "for 350 days a year for 30 years." Stay tuned.