CPSIA is a well-intentioned act. Parents and product safety groups asked the government repeatedly to do something about the seemingly endless stream of unsafe products that were reaching our children. This act seeks to address the unsafe products by requiring testing for lead and phthalates on products intended for kids under age 12. Also included in CPSIA is a new law that makes selling recalled products illegal.
There have been some complaints about CPSIA because the language of the law makes it possible to apply it in a fairly broad way. For example, it could have required all thrift stores and resellers to test their entire inventories for lead, and could have even required you to test all of your baby gear for lead before selling it at a garage sale. Nearly everyone agrees that products for children could and should be safer. The disagreements come with how CPSIA should be interpreted and applied.
The goal of CPSIA is not to police every private citizen who wants to sell an old toy on eBay. In fact, the Consumer Product Safety Commission, the agency that enforces CPSIA, recently announced that thrift shops and resellers would not have to conduct lead tests on their inventories, though they are still expected to exercise caution in choosing products to sell. CPSC expects, though, that these stores will make reasonable efforts to avoid selling items that are more likely to contain lead, such as children's metal jewelry or painted wood or metal toys. The bulk of CPSIA's regulations are aimed at manufacturers and importers of new products, and that is likely where most of the enforcement efforts will be initially, too.
Just because the large companies are the bigger target does not mean that individual sellers of used baby gear are off the hook on CPSIA, though. It is now illegal for anyone to sell recalled products, whether it is an individual or a company doing so. Therefore, it is wise to check for recalls before selling your used baby gear. You can check current baby products recalls here, or you can search CPSC's recalls archive. You can also contact the product manufacturer if you have that information. Providing any model numbers or date codes you can find on the product is usually enough for the customer service department to be able to tell you if the product has been recalled.
Even more than it being illegal to sell recalled products, it is important to take the time to check for recalls because doing so helps remove dangerous products from circulation before any other children can be hurt. The government may never decide to knock on your door for selling something that was recalled, but selling recalled baby products could expose you to other types of liability, particularly if you knew about the recall before the sale. No garage sale dollar is worth a child being hurt, either.
CPSIA does not require you as an individual to test for lead or phthalates before selling your baby's used gear. However, just like thrift stores, it is probably a good idea to be careful in what you decide to sell. Some products are more likely than others to contain lead. As mentioned above, children's metal jewelry and painted wood or metal toys are some examples. Choosing not to sell questionable items should work to reduce the number of toys and baby products with lead that are circulating, and should help keep our children safer over time.

