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The release of copper, mercury, silv^er, tin or zinc from comventional, dispersed phase aod .spherical high copper content aLmalgams immersed in artificial saliva solutions for periods up to 30 d has been measured using nuclear tracer techniques. DTaring initial corrosion, i.e. within a few hourSj substantial amounts of m.eFcury were found to be present in pardculate matter in the three types of amalgams. Tlie release of particulate matter was pronoimced for the dispersed phase type of amalgam. After about 30 d electrocheiBicai corrosion was found to be the predoniinaui: process for release of various corrosion products. Zin.c was demonstr.ated tO' be the major corrosion product released to tine artificial saliva solutions from conventional as well as dispersed! phase amalgams., Due to low radioactivity levels silver and tin could not be qu.anti.taidvely assayed. However, the upper limit&of release of silver and dn in the artificial saliva solutions referring to exposure periods up to 30 d were estimated to O.I \y.g and 25 [ig respectively. The chemical state of tlie various corrosion products has been evaluated. The deposition of CuCla • 3 Cu(OH)2 on the aorfaces of copper rich amalgams was observed according to X-ray diffraction analysis.

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