Acute and chronic exposure of Dunaliella salina and Chlamydomonas bullosa to copper and cadmium: effects of ultrastructure.

The ultrastructural changes of Dunaliella salina and Chlamydomonas bullosa taking place after short term exposure to established copper and/or cadmium EC(50) or exposure to low levels of these cations for 8 months were examined. Cadmium had a greater impact on the ultrastructure of these species than copper. Metal stress affected a variety of cellular parameters including total cell volume, pyrenoid, nucleus, starch granules, polyphosphate bodies, lipids, vacuoles, cell wall, and periplasmalemmal space. The measurements of these cellular parameters used the technique of electron microscopic stereoscopic morphometry. Differences resulting from acute vs. chronic exposure to the cations are documented.