In March 2001, the FDA advised pregnant women and women who may become pregnant not to eat shark, swordfish, king mackerel, or tile fish, because they could contain levels of mercury that could lead to brain damage in a developing fetus. However, the Environmental Working Group, an activist organization, questioned why tuna, although it was included in the initial drafts, was not on the list in the final advisory. Questions were raised as to whether the tuna industry, which accounts for one third of all seafood sales in the United States, had exerted undue influence on the process. As the pressure built, the FDA announced in March 2002 that it would convene a panel of independent scientists to investigate. Their report is expected later this year.