From Yahoo / AP:http://news.yahoo.com/head-fda-stepping-down-chief-scientist-over-143556691politics.html
WASHINGTON (AP) From food safety to tobacco and politically charged drug approvals, Margaret Hamburg reset the course of the embattled Food and Drug Administration, an agency that had often been seen as ineffective.
After nearly six years on the job, Hamburg announced her resignation Thursday in an email to staff. She said the agencys chief scientist, Stephen Ostroff, will serve as acting commissioner
She is among the longest-serving commissioners to head the agency and helped oversee the creation of a new food safety system, reforms in how drugs are reviewed and new tobacco regulations.