If you’re in the beef business, what do you do with all the extra cow parts and trimmings that have traditionally been sold off for use in pet food? You scrape them together into a pink mass, inject them with a chemical to kill the e.coli, and sell them to fast food restaurants to make into hamburgers.

That’s what’s been happening all across the USA with beef sold to McDonald’s, Burger King, school lunches and other fast food restaurants, according to a New York Times article. The beef is injected with ammonia, a chemical commonly used in glass cleaning and window cleaning products.

This is all fine with the USDA, which endorses the procedure as a way to make the hamburger beef “safe” enough to eat. Ammonia kills e.coli, you see, and the USDA doesn’t seem to be concerned with the fact that people are eating ammonia in their hamburgers.

This ammonia-injected beef comes from a company called Beef Products, Inc. As NYT reports, the federal school lunch program used a whopping 5.5 million pounds of ammonia-injected beef trimmings from this company in 2008. This company reportedly developed the idea of using ammonia to sterilize beef before selling it for human consumption.

Aside from the fact that there’s ammonia in the hamburger meat, there’s another problem with this company’s products: The ammonia doesn’t always kill the pathogens. Both e.coli and salmonella have been found contaminating the cow-derived products sold by this company.

This came as a shock to the USDA, which had actually exempted the company’s products from pathogen testing and product recalls. Why was it exempted? Because the ammonia injection process was deemed so effective that the meat products were thought to be safe beyond any question.