Dispersants are all cataloged with the EPA. My last company made them, and toxicity is way lower than the oil it is treating. Most dispersants are amines and stick to the CHONS (Carbon Hydrogen Oxygen Nitrogen Sulfur) regulations. The regulations on marine use dispersant, or even fuel dispersants, are very strict.
Does that mean Gulf shrimp and other seafood from there is safe to eat? I feel like dispersing the BP oil created an out of sight, out of mind situation, rather then actually spending the time and money to clean it up properly.