In another example of dubious “health” information as marketing, some manufacturers of high-tech memory foam sleep materials have begun using a scare tactic to sell their products. These companies are seriously stretching the truth by instilling fear in the public about a common chemical, methylenediphenyl diisocyanate, or TDI. By trumpeting the somewhat exaggerated dangers of TDI, these companies position themselves to provide a “safer” alternative.

TDI has been in use for decades in the production of memory foam sleep products and virtually every other kind of polyurethane foam. The chemical is used in the production of shoe soles, car seats, furniture cushions and literally thousands of other items we use on a daily basis. TDI is used as a catalyst, initiating the chemical reaction that turns liquid foam into solid foam.

For the purposes of this article, an important distinction must be made between TDI in the manufacturing process and TDI in end-use consumer products. In its raw form, TDI does indeed pose significant health risks including cancer, and there are strict guidelines for the safe handling of TDI in the workplace. However, as dangerous it may be in the production process, consumers never encounter TDI in their finished products. According to the Polyurethane Foam Association, by the time foam products leave the factory, the TDI has been consumed and metabolized through chemical reactions. That means that by the time you lace up your shoes or settle into your sofa, TDI is no longer present in the polyurethane products you use.

Because of the risks associated with TDI in the workplace, some marketers have seen an opportunity to scare consumers with half truths, and sell more of their products. By massaging data on workplace risk, they can create the illusion that TDI is dangerous to consumers as well, but claims like these are simply an old fashioned scare tactic. Indeed, many of the products we use have dangerous chemicals involved in their production. Highly toxic mercury is often used in the production of gold to separate metal particles from surrounding impurities, but that doesn't mean that your wedding ring will harm you.

If TDI was truly a health risk to consumers, or even a cancer risk as some have suggested, we would be feeling its effects every day. Approximately 1.5 billion lbs of TDI were produced in the U.S. in 2000, much of which was consumed by U.S. manufacturers. The chemical is in widespread use, and is produced and consumed in huge quantities in the U.S, where we have some of the most rigorous health guidelines in the world. If TDI was truly dangerous to consumers, many of the products you use every day would pose a serious risk to your health.

The companies using these scare tactics put forward diphenylmethane diisocyanate, or MDI, as a “safer” alternative to TDI. While MDI could be considered somewhat safer for use in the workplace, that has nothing to do with the risks associated with a finished product.

The EPA's recommended exposure levels for MDI are virtually identical to those for TDI, and the warnings for both compounds are directed at workplace risk, not consumer risk. In fact, the two compounds are so closely related, and the health risks so similar, that most articles on the subject discuss isocyanate compounds, which include both MDI and TDI, as a group rather than individually.

Besides the marketing opportunity, there are also very practical reasons for these companies to eliminate TDI from their production processes, and most have to do with the bottom line. Because MDI is slightly less volatile and less toxic in the work environment, it requires fewer costly safety measures like increased ventilation, etc. However, one drawback to MDI, and one reason why all companies haven't made the switch, is because the use of MDI makes it more difficult to make truly durable foam. Ultimately, manufacturers using MDI are more concerned about workplace lawsuits and their bottom line than they are about their customer's safety.