The validation of atrazine nominal concentrations is shown in
Table1. Measured concentrations were close to the nominal ones.
Therefore, the latter will referred hereafter. Table2 shows the
results of survival and molting. No significant differences
(p>0.05) were noted in survival between control and any atrazine
concentration, therefore indicating that all concentrations assayed
were sublethal. Overall grand mean of survival was near 83%.
Because juvenile crayfish often eat their molts(Jones, 1997), those
eventually observed throughout the experiments were not quan-
tified for statistical analysis.