Effects on uptake by and metabolism of aldrin and phorate in a protozoan, Tetrahymena pyriformis

Growth of Tetrahymena pyriformis was retarded by aldrin (10, 20 and 50 ppm) and phorate (1, 10 and 20 ppm) but the organism showed a tendency to recover from the toxic effects of these insecticides with time. At 100 ppm of aldrin and 50 ppm of phorate, the organisms lysed within 6 h of treatment. The organism picked up 32.1 to 924.3 ppm of aldrin and 21.1 to 948.1 ppm of phorate from culture media containing 0.1, 0.5 and 1.0 ppm of aldrin and 2.5, 5 and 10 ppm of phorate respectively. Uptake and bioconcentration by the organism of aldrin and phorate has been inversely dependent on their water solubility. Tetrahymena pyriformis metabolized aldrin to dieldrin while phorate was unchanged by the organism.