Figure 3.

Brine shrimp mortality and particle accumulation after 24 h. Error bars indicate standard deviation. Solid and dashed lines represent linear regression and 95% confidence bands, respectively. *p < 0.05, **p < 0.01 compared to untreated, #p < 0.05, ##p < 0.01 compared to 200 mg/L benzene. A) Mortality after exposure to CB dispersants and activated carbon. B) Mortality after coexposure to 200 mg/L benzene and particle dispersants. C) Mortality after benzene exposure. D) Calculated values for particle: effective concentration for adsorption of 50% of 200 mg/L benzene onto the carbon surface; reduction of brine shrimp mortality following coexposure to benzene at 200 mg/L by 50%; and LC₅₀ for particles alone. E) The untreated brine shrimp image to the left of the panel demonstrates anatomical features at time of exposure. 1: mouth (underneath and not visible), 2: sensory antennule, 3: locomotory antenna, 4: nonfunctional limb buds, 5: gut lumen. The panel of images at right shows uptake and accumulation of particles on the exoskeleton of whole brine shrimp after 24 h at 100 mg/L (i-iv) and 500 mg/L (v-viii) for all three CB forms and PAC. Red arrow indicates rod-like bundles of excreted particles; blue arrow indicates gut uptake of particles. Scale bar indicates 500 μm.