CHARLESTON,, W.Va. -- As state and federal agencies respond to the chemical spill on the Elk River in West Virginia, it is the health and welfare of area residents that is at the forefront of everyone's thoughts and concerns. The spill has contaminated the drinking water for hundreds of thousands of people, threatens long-term environmental damage and could have other unknown consequences.Aside from the human impacts of this catastrophe, one of the most troubling aspects of this accident for policymakers should be the fact that we were not prepared to appropriately deal with the spill, largely because we do not understand the toxicological nature of the substance itself. There seems to be little, if any, well formulated data to indicate just how toxic the chemical is, and what exposure levels pose real human health risks.This should be an educational moment for Congress, which is currently in the middle of a long debate over how to best reform our laws that address chemicals in commerce. The law that currently governs these matters -- and should make sure we have information about these types of hazards -- is the Toxic Substances Control Act (TSCA).TSCA is 38 years old and is in desperate need of updating. Various interests and the two political parties have been moving closer to a consensus on exactly what reform of this law should include. This chemical spill should show them one thing: We need better toxicological data on more chemicals, and we need it sooner rather than later.Stakeholders in the issue of chemical regulation have long agreed that advancing alternative testing methods would be in the best interest for all involved. Industry has embraced alternative testing, or in vitro testing, as a way to cut costs and review time over animal testing, which is expensive and slow to produce usable data. Environmental and public health advocates have argued that advanced alternative testing would provide an abundance of data in a timely fashion that regulators could use to determine potentially dangerous substances. Animal welfare advocates have also pushed for less reliance on animal tests as a way toward a more humane system. The U.S. National Academy of Sciences, in a 2007 report, agrees.Recent scientific advances offer to fundamentally change the way chemicals are tested for human health risks. These advances, which include in vitro testing, make it possible to rely less heavily on animal studies and instead focus on evaluating chemicals' effects on biological processes. Through this approach, scientists can generate improved data to evaluate risks while expanding the number of chemical assessments using less time and money and fewer animal subjects. Several federal agencies -- the Environmental Protection Agency, the Food and Drug Administration and the National Institutes of Health -- embraced this approach and are working hard to further develop the science to make this vision a reality.The people impacted by this spill are understandably concerned for their families' safety. Local, state and federal public health agencies are equally concerned as that is their charge. What is missing is real data that could easily be obtained by applying a little science and a lot of political goodwill.Locke is an associate professor at the Johns Hopkins Bloomberg School of Public Health, Department of Environmental Health Sciences, Division of Molecular and Translational Toxicology.