The teenage years are the last golden opportunity to build a healthy brain, researchers say. So smoking pot might not be so smart. Tomas Rodriguez/Corbis hide caption

itoggle caption Tomas Rodriguez/Corbis

Research in mice offers new clues as to why Harold and Kumar were so motivated to get to White Castle. Todd Plitt/Getty Images hide caption

itoggle caption Todd Plitt/Getty Images

Truffles are among the many foods infused with THC – the chemical in marijuana that gives you a high — already for sale in Colorado. Luke Runyon/KUNC/Harvest Public Media hide caption

itoggle caption Luke Runyon/KUNC/Harvest Public Media

The legalization of marijuana could dry up a revenue stream for police, according to reports. Here, two men share a water pipe underneath the Space Needle shortly after a law legalizing the recreational use of marijuana took effect in Seattle in 2012. Stephen Brashear/Getty Images hide caption

itoggle caption Stephen Brashear/Getty Images

This dead juvenile coho salmon was found in a tributary of California's South Fork Eel River. About 20 large-scale marijuana farms are located upstream from the watershed pictured. All of them divert water from the stream. Courtesy Scott Bauer hide caption

itoggle caption Courtesy Scott Bauer

New York Gov. Andrew Cuomo is reportedly considering allowing the use of marijuana for medicinal purposes. Tim Roske/AP hide caption

itoggle caption Tim Roske/AP

A man uses the Nasal Ranger to detect smells in the southern U.S., in this photo provided by St. Croix Sensory. In Denver, the device is being used to monitor complaints of strong marijuana smells. Courtesy of Nasal Ranger hide caption

itoggle caption Courtesy of Nasal Ranger

An aerial image shows the Gold Star cargo ship ablaze. Officials say the ship's crew set fire to 30 tons of hashish after authorities approached the vessel for inspection. Guardia di Finanza hide caption

itoggle caption Guardia di Finanza