We received word Wednesday that seven medical marijuana dispensaries permitted by the City of San Francisco are being investigated by the Drug Enforcement Administration. In Sept. 2012, D.E.A. agent David White requested from San Francisco the public records of: Ketama Collective; Igzactly 420; 1944 Ocean Collective; The Hemp Center; Mr. Purple Skunk; The Apothecarium; and Bernal Heights Collective.