70% of ALL Beef and Chicken has been treated with Carbon Monoxide Gas. It makes bad meat look good even though it may have spoiled. The practice of treating meat with carbon monoxide could hide thegrowth of pathogens such as Clostridium Botulinum, Salmonella and E. coli O157:H7.
That's just one of maaaany facts.
Here's a good article from McDougall: http://www.drmcdougall.com/misc/2007nl/may/meat.htm