WASHINGTON, Oct. 24 -- Sen. Roger Marshall, R-Kansas, issued the following news release: * * * Senator Marshall Tours Clinical Reference Laboratory & Highlights Dangers of Synthetic Kratom Compound "7-OH" * Lenexa - On Friday, U.S. Senator Roger Marshall, M.D. (R-Kansas), joined leaders from the Clinical Reference Laboratory and the Midwest High Intensity Drug Trafficking Area (HIDTA) to raise awareness about the growing threat of 7-hydroxymitragynine (7-OH) - a powerful, unregulated opioid  more PR