The controversial Consumer Product Safety Improvement Act (CPSIA), which strengthens regulations on children's products containing lead and the plastic component phthalate, took effect Tuesday, amid a flurry of protest from retailers and manufacturers.

Manufacturers must certify lead amounts do not exceed 600 parts per million and that all items created after Feb. 10 contain less than 0.1 percent phthalate. While thrift stores are not required to test old products they resell, any retailer selling a children's item violating the act is liable for civil or criminal prosecution.

“You can do things surgically or you can do things with a sledgehammer, and what we have is sledgehammer legislation when a surgical instrument would have been fine,” said Sandra Ezell, a managing partner at Bowman and Brooke. She said she believes the broad “toxic toy ban” goes too far and will put an undue burden on companies with a history of reasonable and responsible attention to safety.

Walter Olson published reports on his blog, Overlawyered.com, of thrift stores throwing out hundreds of children's books printed before 1985, which the CPSIA said have potentially unsafe levels of lead in the ink.

Other resale shops have discarded scores of pieces of children's clothing with snaps, zippers and buttons that fall under the act's jurisdiction.

Though the burden of proof typically falls on the plaintiff to scientifically prove a questionable item harmed a child, Ezell said the act encourages juries to unfairly place the burden on the defense. Manufacturers could anticipate an increase in class actions over the potential harm of toys bought prior to the ban, she said.

“There are a lot of excellent products and excellent companies who are going to be victims of legislation where they basically had no dog in the fight, and they are not going to survive it,” she said.