The Deepwater Horizon oil spill in the Gulf of Mexico happened over three years ago, but according to scientists, crude oil toxicity still continues to sicken a sentinel Gulf Coast fish species. Researchers from the University of California, Davis, teamed up with researchers from Louisiana and South Carolina to find that Gulf killifish embryos exposed to sediments from oiled locations in 2010 and 2011 show developmental abnormalities, including heart defects, delayed hatching and reduced hatching success.