Most of the drywall that has recently been linked to problems was from China.
- Use a drywall that is made in the U.S., preferably by a manufacturing plant close to you. You should research where the closest plant is.
- Also, select one that uses a high percentage of recycled content, such as U.S. Gypsum's Sheetrock.
In finishing your wall, make sure that the joint compound, sealer, and paint are nontoxic and low or no-VOC.
For more information:
Also, read Nick Cope's Q&A "Is there a drywall alternative that's safe for our new baby's nursery?"