In Iowa, 20 U.S. Food and Drug Administration inspectors are focusing on the two big egg farms involved in a massive recall, looking for commonalities among the windowless hen houses where the eggs were laid.
"They may have to look many places -- the chicken, and the eggs, at the chicken litter, the feed, the dirt, workers boots, processing equipment, fan blades many things could be a source of contamination," said William Hubbard, a former FDA associate commissioner.
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Source: ABC News