A comparison of the effects of chlordane and PCB on the growth, photosynthesis, and cell size of estuarine phytoplankton☆
Abstract Daily additions of 10μg chlordane (a chlorinated insecticide, C10H6Cl8) or 5 or 10μg Aroclor 1254 (polychlorinated biphenyls, PCB) to 1 litre of dialysis culture consisting of mixed species of estuarine phytoplankton, reduced algal growth rate and 14C-uptake per unit of chlorophyll a. Inhibition by chlordane lasted 24 to 48 h, and the community cell-size distribution was not substantially altered. PCB, however, caused longer-term effects, inhibiting the growth of phytoplankton larger than 8 μm in equivalent spherical diameter (i.e. large centric diatoms) more strongly than that of smaller forms (pennate diatoms and microflagellates), so that the community composition shifted in favour of small-size algae.