Effectiveness and Toxicity of Chemical Dispersant in Oil Spill Aquatic Environment

Pollution of the marine ecosystem by crude oil spill endangers marine species. The use of chemical dispersants in removing spilled oil from the marine environment by forming oil-in-water emulsions proves to be relatively effective, but the effectiveness is influenced by a number of factors. However, the successful use of these dispersants depends, to a great extent, on the toxicity of the oil-dispersant mixture that forms when dispersants are applied to combat oil spills. In this review, the type and quantity of dispersant used were reported to influence the toxicity of the oil-dispersant mixture on aquatic organisms relative to both the crude oil and the dispersant. The viscosity of oil, the salinity of water and the quantity of dispersants used were discussed as major factors influencing the effectiveness of dispersants. With contrasting results in assessing the overall toxicity of oil-dispersant mixtures on marine life, recommendations were suggested at the end of this review.