Any material that has glue to hold it together in going to have some off gassing. As to what type of glues were used on those products I could not tell you without more detail.
It has been suggested that off gassing from glue solvents does have harmful effects on people.
For your own peace of mind I would suggest 1x4 or 1x6 planks for the mattress support.
For more information:
Read "I'm concerned about toxic offgassing from OSB subflooring and roofing. Are safer products available?" a Q&A answered by Ian MacLeod.