Analisis logam berat Pb, Cd, dan Zn pada materi organik dan anorganik spons spheciospongia vagabunda di Pulau Pramuka, Kepulauan Seribu, Jakarta = Analysis of heavy metal Pb, Cd, and Zn on organic and inorganic materials of sponge spheciospongia vagabunda in Pramuka Island, Seribu Islands, Jakarta.