EFFECTS OF TIN(IV) CHLORIDE AND OF ORGANOTIN COMPOUNDS ON AQUATIC MICROORGANISMS

The growth response of the alga Chlorella kessleri and the euglenoid E uglena gracilis has been studied as a model system to determine the ef fects of a tin salt (SnCl4 . 5H(2)O) and of some organotin (OT) deriva tives, namely tetrabutyltin (TeBT), tributyltin (TBT) and tributyltin oxide (TBTO), Abiotic degradation was studied as well, Cells were expo sed to a toxicity series (0-50 mu g/mL(-1)) for the four chemicals in seven-day bioassays, Both microorganisms are tolerant of the inorganic salt, but growth inhibition was significant for all OT compounds, and especially large for TBT and TBTO, Although C. kessleri and E. gracil is are known to be tolerant towards metals and organic chemicals, the present results show that both are sensitive to organotin compounds: t he inhibition of the growth was greater for C. kessleri. (C) 1998 John Wiley & Sons, Ltd.