Ever health-conscious, California has established the nation's first statewide program to monitor the levels of chemical contaminants in humans. Last fall, the state legislature passed a bill that creates a framework for public health officials to test volunteers for toxic substances like mercury, pesticides, PCBs, and flame retardants. The results will inform studies of vexing diseases with suspected environmental causes: autism, cancer, and heart disease to cite a few examples. The program will also allow Californians to compare their own chemical exposure with statewide averages. "People ask to be tested for various toxic chemicals, but I often have to turn them away because there are no standards against which I can compare their results," says Gina Solomon, a medical doctor and NRDC senior scientist who provided scientific guidance to the bill's sponsors.