Explainer

Eggsplainer!

A roundup of questions on the salmonella outbreak.

How many eggs is 550 million eggs?

Some 550 million eggs have been recalled in connection with a salmonella outbreak —“probably the largest egg recall that has happened in recent history,” according to FDA commissioner Margaret Hamburg. The Explainer, who has not yet checked the plant number and Julian date on her personal carton, has a few questions:

According to new FDA regulations, if an egg tests positive for salmonella, it must be treated to destroy the bacterium or diverted to “non-food” uses. What are “non-food” uses for eggs?
The albumin, or egg white, is used to finish certain types of leather (it provides a nice glaze) and as a clarifying agent in various chemical processes. Eggs are also used in certain plant fertilizers and in the production of vaccines, including for the flu. (That’s why people with severe egg allergies are told to consult a physician before getting the flu vaccine.)

Health officials are recommending that consumers either throw away potentially tainted eggs or return them to the store where they will be destroyed. Is there some FDA guideline on how to get rid of a bad egg?
No. It seems retailers are mostly throwing returned eggs in dumpsters. When the Hallmark/Westland Meat Packing Co. recalled 143 million pounds of beef in 2008, the USDA recommended taking the meat to landfills or incinerating it.

What would 550 million eggs look like if they were all in one place?
If you stacked 550 million eggs in a tetrahedron, the structure would come to a point about 1,500 levels off the ground, or a couple of hundred feet. Eggs range in size, but 2 ounces is a pretty typical weight. If you weighed your egg pyramid, it would come out to about 70 million pounds.

Isn’t there always a risk of salmonella poisoning with eggs? What makes the current outbreak so bad?
Because so many people have gotten sick. The most common strain of salmonella, and the one causing the outbreak, is called Enteritidis. In a given week, the Centers for Disease Control gets about 50 reports of Enteritidis food poisoning. But in May that number jumped to about 100, and it reached more than 200 in late June and early July. This four-fold weekly increase raised the prospect that the cases weren’t random and isolated but could be traced to a small number of sources—in this case, two big farms in Iowa.

In general, the risk of salmonella is low—about 1 in 20,000 eggs are infected, which means an average consumer who consumes 250 eggs per year will come in contact with a bad product just once in 80 years. While people are always encouraged to handle raw eggs with caution, the risk is so high with this particular batch that it’s best to get rid of them entirely.

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Explainer thanks J.D. Hanson of the Center for Food Safety and Michael P. Doyle of the University of Georgia.

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