Fig. 2

Embryo toxicity (a), heart beat (b) and cumulative hatching (c) of Danio rerio embryos after exposure to native sediments of Gulf of Bothnia. Experiment was performed in 3 independent replicates (20 embryos). ISO-Water was used as negative control and 3,4-dichloroaniline was used as positive control (3.4 mg/L). The symbol * indicates a statistical difference between treatments or between treatments and the control (p ≤ 0.01). The symbols a and b indicates a statistical difference between treatments (p ≤ 0.01). Error bars represent standard deviation