Experiments on the accumulation of lindane (gamma-BHC) by the primary producers Chlorella spec. and Chlorella...

Experiments were performed on the accumulation of the pesticide lindane (gamma-isomer of BHC) by two algae with different surfaces. An analytical procedure was developed for the gas chromatographic determinnation of lindane. At room temperature, lindane had a water solubility of 7.8 mg/L in distilled water and 6.7 mg/L in tap water. Under the experimental conditions of 10 to 100 microgram/L, 2.3% of the dissolved lindane was lost through adsorption on the glass walls of the equipment and 0.2% through evaporation. The recovery rate of lindane was 98% for the water samples and more than 90% for Chlorella spec. The tolerance in the gas chromatographic measurements amounted to 1.2%. Investigations on the effect of lindane on the growth of Chlorella spec. revealed irreparable damage to the algae cells through loss of chlorophyll, coagulation, and complete sedimentation at concentrations greater than 300 microgram/L. The experiments on sublethal accumulation showed the development of a state of equilibrium between the amount of lindane per cell and in the surrounding water with lindane concentrations of 10 to 100 microgram/L. The lindane was adsorptively attached to the algal cells within a few hr, and after three days lindane stabilized in the cells. The gelatinous surface of the algae increases the accumulation of lindane.