Memory-foam mattresses have the same problem apparently. I have one, and am looking into a dust mite bed casing (~$100) to prevent the chemicals from getting into the air...
http://lesstoxicstuff.com/2011/09/how-to-reduce-your-familys...
http://lesstoxicstuff.com/2011/09/how-to-reduce-your-familys...
We recently switched to a bed that strictly consists of natural materials like wood, latex, cotton and natural rubber. Absolutely no metal and no toxic additives. Costs as much as our car, but is worth every cent. Sleeping feels like holiday now. I also can smell the difference.