Redrawing the dose-response curve

For more than 450 years, toxicologists have believed that Paracelsus got it right when he determined that the dose makes the poison. Accordingly, the generally accepted thinking about health effects from environmental contamination holds that a chemical found to be toxic at high doses will simply have no observable adverse effect at low doses. But environmental toxicologists have known for years that dioxin does not follow this pattern, and a growing group of scientists are beginning to question whether dioxin is an anomaly. Rebecca Renner examines the emerging science surrounding the concept of hormesis, which characterizes substances like red wine that stimulate effects at low doses but inhibit them at higher doses. In other words, could the, dose make the cure?