Hardboard and Formaldehyde

May 26, 2009, by Debra Lynn Dadd

Question from Miemiemuis

I was wondering whether hardboard contains any formaldehyde. I’m fixing an old wood dresser and the bottom of the draws are hardboard/pressed wood that urgently need to be replaced and I want a replacement that will not off gas anything toxic. Should I seal it? 

Thanks! 

Debra’s Answer

That piece of wood at the bottom of dressers is usually pressboard, which is made by simply steaming small wood chips together under pressure. The natural lignins in the wood stick together of their own accord, without any additional resins. However, additional chemicals can be added to moisture control and strength.

Particleboard, on the other hand, is made by mixing wood chips with a resin that contains formaldehyde, and the formaldehyde outgasses from the particleboard over time until it is gone. Depending on conditions, this can take years.