The levamisole test kit for cocaine

Typically, it's difficult for drug users to reliably test their drugs for impurities -- it requires expensive, unstable, and sometimes dangerous chemicals used in laboratory conditions. But when Nathan Messer, head of the local drug-harm-reduction group DanceSafe, got in touch with a doctor in Seattle named Mike Clark (a psychiatrist and molecular biologist at Harborview) about levamisole, Dr. Clark had a moment of inspiration. He was already familiar with levamisole. He'd been using it in his lab for years, as a way to block an enzyme that interferes with certain color-change reactions in tissue samples. (Technically speaking, levamisole inhibits most types of mammalian alkaline phosphatase -- it slows the enzyme to a crawl, preventing it from working.) Dr. Clark's idea was to inhibit the enzyme and then test for the inhibition.

The result: DanceSafe and Dr. Clark created an easy-to-use kit out of inexpensive materials that tests for levamisole. The Stranger is paying for some of the materials, helping to distribute the kits, and collecting anonymous data about what we learn.