Uptake and elimination of lindane by Lymnaea palustris (Mollusca: Gastropoda): a pharmacokinetic approach.

The uptake and elimination of lindane by adult Lymnaea palustris (Müller) were studied using a static contamination system. First-order one- and two-compartment models were used to quantitatively describe these phenomena. The accumulation of residues was triphasic and the observed steady-state bioconcentration factor lay between 36.8 and 56.4 but did not significantly depend on the initial lindane concentration (6, 60, and 600 micrograms liter-1). Accumulation was inferior to that observed for other aquatic organisms and this was attributed to the relatively low lipid content of L. palustris tissues (mean of 0.81 +/- 0.17% of fresh weight). The transfer of snails to lindane-free water after 72 hr of exposure was followed by a biphasic elimination of residues with a half-life of 0.7 hr in the central compartment and of 130.2 hr in the peripheral compartment. Additional experiments showed that the residues enter the snails through the foot and are afterward stocked within the visceral mass which contains approximately three times more lipids than the foot (1.03 +/- 0.13% of fresh weight vs 0.37 +/- 0.03%).