Thousands of chemicals are in use today, but few have been fully evaluated for potential health risks. One big gap are cases in which toxicity can develop from the way our bodies process chemicals in our livers and kidneys. On July 8th, the U.S. Environmental Protection Agency (EPA) and National Institutes of Health (NIH) will convene participants of their Transform Tox Testing Challenge in a public workshop in Research Triangle Park, NC to discuss how we can fill that gap.