It used to be that if you wanted to smoke pot, you smoked whatever you could get your hands on. Quality, safety, and potency was a matter of sight, smell, and, to a certain degree, taste. But that simply doesn't cut it in a regulated medical marijuana market. Consumers like to know exactly how strong a weed they're buying, and they want some assurances that it hasn't been doused in pesticides or colonized by insects or mold. Stepping into the white lab coat since 2008 is Oakland company Steep Hill Lab. Founded by two Northern California growers in an Emeryville apartment, the company has grown to become the premier cannabis tester in the West, with customers that include Harborside Health Center and San Francisco Patient and Resource Center. It helped form the Association of California Cannabis Laboratories to promote best practices in the nascent, quasi-legal field, and it launched a SafeCannabis program that moves testing up the supply chain from the stores to the farms themselves. For doggedly pursuing the vision of a cleaner, safer stash, Steep Hill Lab is clearly the best medical marijuana lab in the East Bay.