Deepwater spill still killing fish

The oil released during the BP Deepwater Horizon disaster may damage fish populations in the Gulf of Mexico for years to come. New research from the National Oceanic and Atmospheric Administration found that exposure to crude oil can cause heart defects in fish embryos—abnormalities that will likely kill many developing fish and shorten the lives of others. The study looked at bluefin and yellowfin tuna and amberjacks, key commercial and ecological species. “You mess up the heart, you mess up the ability of species like this to do simple functions like swim and catch prey,” environmental toxicologist Fernando Galvez tells CNN.com.

The April 2010 accident, which unleashed some 4.1 million barrels of oil into the Gulf, coincided with spawning season, when fragile embryos would have been floating on the surface. The study mimicked real-life events, exposing developing fish to oil collected from the Deepwater source pipe and surface-skimming operations. Defects included physical distortions in the hearts, body shapes, and eyes of embryos. BP disputed the findings, saying researchers exposed the fish to higher concentrations of oil than were seen in the wild. But scientists maintain that even minimal exposure to petrochemicals resulted in critical malformations.