What Kills Anthrax?
WebMD News Archive
Oct. 30, 2001 -- Scared of anthrax in your mail? Use your head -- and not your iron or your microwave, experts advise.
First, use common sense. If you receive mail you suspect may contain anthrax, leave it alone. Follow the CDC's advice on what to do. (We've reprinted it below). Leave the decontamination to hazardous-materials experts.
"You are not supposed to be doing this on your own," warns anthrax expert Philip C. Hanna, PhD, professor of microbiology the University of Michigan, Ann Arbor.
What makes anthrax such a scary germ is that it travels in the form of spores. These nearly lifeless seeds hide inside a hard shell and can't be hurt by freezing cold or boiling heat. They wait for the right conditions to bloom into deadly bacteria.
The recent anthrax attacks have everybody's nerves on edge -- and have the rumor mills running full-speed. One rumor would have you iron all of your mail. Another would have you put it in the microwave. Would any of this work?
"Microwaving your mail won't do it," Hanna tells WebMD. "First of all, microwaves work by heating water, and spores have no water in them. It is like putting your empty coffee cup into the microwave -- it won't get hot. And even if you had water, spores can survive boiling."
So what about that hot iron? You could do more harm with it than good.
"The temperatures an iron gets to can kill spores. But you have to do it for a length of time that is more likely to burn your mail than kill the spores," Hanna says. "And if steam builds up inside the envelope, it can spray out and get the spores into the air."
If your mail isn't particularly suspicious, but you just don't want to deal with it, there is something you can do. "You can incinerate spores -- so if you want to burn your mail, it's OK," Hanna says.
Such a drastic step seems unnecessary. The U.S. Postal Service already is sending some mail to be sterilized by electron-beam machines. It's bought eight of the machines -- at $5 million each -- for delivery next month. There are plans to buy several hundred more. The machines were designed to sterilize medical devices and to get rid of germs in food products. Manufacturer Titan Corp. says the high-energy electrical beams can safely kill anthrax spores. Current plans call for the machines to be used on person-to-person and consumer-to-business mail -- which account for some 40 billion pieces of mail each year.
Other companies are getting into the act. The public/private Sandia National Laboratories -- operated by Lockheed Martin Co. for the U.S. Department of Energy -- has created an environment-friendly decontamination foam that kills anthrax spores.