Abstract There is increasingly evidence that human exposure to levels of chemicals once thought to be safe -- or presenting insignificant risk -- are, in fact, harmful. So-called low-level exposures are now known to be associated with adverse biological effects including cancer, endocrine disruption, and chemical sensitivity. This requires that we change both (1) the way we design research linking chemicals and health, and (2) the solutions we devise to address chemically-caused injury. The new and emerging science of lowlevel exposure to chemicals requires appropriate social policy responses which include regulation of toxic substances, notification of those exposed, and compensation and reasonable accommodation to those affected. Research and social policy needs to be focused towards two distinct groups: (1) those individuals who could become chemically intolerant as a result of an initiating exposure and (2) those individuals who have already become chemically intolerant and are now sensitive to chemicals at low levels.