As China prepared to host the 2008 Olympics they passed a summer ban on pollution, reducing particulate and other airborne emissions in the environment. A group of researchers led by Jim Zhang, Ph.D. from the University of Southern California in Los Angeles used the pollution ban as an opportunity and studied the effects of the environmental changes on cardiovascular biomarkers. After analyzing samples from 125 healthy individuals before, during, and after the restrictions were in place the investigators found a significant dip in soluble P-selectin and von Willebrand Factor levels. Other (less significant) changes in related protein concentrations during the time of the ban were observed and most of the biomarker levels rebounded after the ban was lifted. The study, published in the May issue of the Journal of the American Medical Association, while limited does lay the groundwork for further research linking air pollution and cardiovascular risk.