How healthy is memory foam in a mattress or pillow?

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You may have noticed a strong smell being emitted from memory foam? This is the off-gassing of toxic chemicals and can be noticed for months in some cases.  These emissions have been associated with headaches and other severe health reactions in people who sleep on them.  You can learn more about the health effects of memory foam and conventional mattresses from http://www.chem-tox.com/guest/guestbook.html