Oil spills and sunlight not a good mix for fish

Exposure to sunlight in the event of an oil spill lowers the survival rates of fish that live near the surface during their larval stage.

This was the conclusion reached by researchers after studying species native to the Gulf of Mexico.

They concluded that the contaminants called polycyclic aromatic hydrocarbons (PAHs) found in oil spills, especially in the presence of the sun's ultraviolet radiation, generates conditions that are toxic to the wildlife.

"Many marine and estuarine fish eggs and early larva develop at or near the water surface, which is where oil floats and the sun shines. When all three co-occur, the potential for toxicity greatly increases," said Dr Matthew Alloy, a postdoctor research fellow at McGill University, and lead author of the study, which was published in the current issue of Environmental Toxicology and Chemistry.

Although the research is not the first to study photo-induced PAH toxicity, it is the first to focus specifically on such toxicity in the Deepwater Horizon oil spill and involved species native to the Gulf of Mexico.