As a society, we’re becoming increasingly protective of our health. We’ve dramatically cut back on smoking compared to a generation ago. We drink purified water and eat organic foods. But there’s one thing many of us fail to consider the health implications of: our mattress.

You spend eight hours a day with your nose pressed up against this giant, synthetic rectangle. Do you even know what it’s made of? If not, you should.

Memory foam mattresses have become increasingly popular in recent years. As an alternative to the prohibitively expensive prices of some mattresses on the market, a new wave of mail-order memory foam mattress companies has emerged. Such companies boast all of the benefits of a memory foam mattress from a brick and mortar store at only a fraction of the price.

However, not all memory foam mattresses are created equal. In fact, some of them can even be hazardous to your health.

Such mattresses are frequently treated with toxic chemical sprays and produce other toxic byproducts. On a short-term basis, exposure to such toxins can result in headaches, nausea, skin irritation and burning of the eyes, nose and throat. With sustained exposure, the impacts can be as extreme as respiratory problems and organ or nervous system damage.

When shopping for a memory foam mattress, here are the top chemicals to avoid:

  • Acetone
  • Dimethylformamide
  • Formaldehyde
  • Methyl benzene
  • Methylene chloride
  • Methylene dianiline (MDA)
  • Vinylidene chloride

Unfortunately, finding a safe memory foam mattress isn’t as easy as checking an ingredients list. Memory foam is considered a trade secret–and the law does not require manufacturers to disclose their products’ ingredients. However, mattress suppliers that do not use such harmful toxins will clearly advertise this fact.

To avoid winding up with a hazardous product in your home, it pays to do some extra research on mattress quality before you buy.