
Fig. 1. Median survival times (±95 % CI) for 7 days postfertilization
zebrafish exposed to various concentrations of MS222 in normoxic fresh water.
The dashed line indicates the regression equation based on median survival
times (ET50) between 50 and 200 mgl-1. The slope of this
line was not significantly different from zero (P>0.05). Values in
parentheses indicate the percentage of larvae ventilating their gills at the
various MS222 concentrations. 0 % gill ventilation continues as indicated by
the horizontal arrow. The vertical arrow indicates <50 % mortality.