work. their studied shows the genes of killy fish had developmental abnormalities, heart defects, dna and other changes. the lab results corresponded with real world outcomes. we've invited bp to join us all week to discuss all of these issues surrounding the spill but they, of course, have declined. bp did direct us to their blog at state of the gulf.com. the blog refutes the uc davis study and points to an october 2014 study that found no minimal long-term impact on killifish. joining me today is dr. andrew whitehead, a professor at the environmental toxicology department at uc davis. also a physician from south louisiana who has treated over 100 patients who were exposed to the products of the spill. gentlemen, great to have you with us tonight.