The Carbon Nanotube Registry is a roster of U.S. workers employed in various carbon nanotube industries. The registry can be used to study long-term health effects. Researchers will track workers in the registry to see whether higher rates of disease are observed compared to other workers or the general population. The more workers included in the registry, the more powerful and informative the study will be. If you are interested in participating, please contact nano@cdc.gov.