A bill headed for President Barack Obama this week includes a provision that would ban U.S. imports of fish caught by slaves in Southeast Asia, gold mined by children in Africa and garments sewn by abused women in Bangladesh, closing a loophole in an 85-year-old tariff law that has failed to keep products of forced and child labor out of America.

An expose by The Associated Press last year found Thai companies ship seafood to the U.S. that was caught and processed by trapped and enslaved workers. AP tracked fish and shrimp from people locked in cages and factories to supply chains of top retailers and restaurants, from supermarket chains like Wal-Mart and Whole Foods to restaurants including Red Lobster. The companies all said they strongly condemn labor abuse and are taking steps to prevent it.

As a result of the reports, more than 2,000 trapped fishermen have been freed, more than a dozen alleged traffickers arrested and millions of dollars worth of seafood and vessels seized. Thai Union, one of the world’s biggest seafood exporters, says it has hired 1,200 workers from outsourced shrimp processing sheds into safer, more closely regulated in-house jobs with decent pay.

On Capitol Hill, the AP investigation, along with other press reports and political advocacy, helped pressure lawmakers “to finally strike this obscene provision of U.S. law,” said Sen. Ron Wyden, an Oregon democrat.

“It’s an outrage this loophole persisted for so long. No product made by people held against their will, or by children, should ever be imported to the United States,” he said.

The change is part of a wide-ranging bill which revamps trade laws and bars Internet taxes passed on a vote of 75-20 by the Senate Thursday. President Barack Obama is expected to sign it.

The U.S. Tariff Act of 1930 gave Customs and Border Protection the authority to seize shipments where forced labor is suspected and block further imports. However, it has been used only 39 times in 85 years in large part because of an exemption that said goods made by children, prisoners or slaves can be allowed into the U.S. if consumer demand cannot be met without them. Drafted during the Depression, lawmakers at the time placed economic need over foreign labor rights, according to legal historians.

If signed by President Obama, imports of a Labor Department list of more than 350 goods produced by child or forced labor — cotton from Kazakhstan, wheat from Pakistan, lobsters from Honduras — may now face federal law enforcement.

David Olave, a Washington D.C.-based trade consultant, said he’s concerned about unfair and overreaching seizures by Customs and Border Protection investigators who would be hard pressed to prove a product in a particular shipping container was picked or processed by a forced laborer. And he said U.S. firms have already been proactive in trying to keep labor abuse out of their supply chains, well ahead of government regulations.

“From my perspective, this is more of an image issue,” he said, “It looks bad, to have a law that says we want to stop child labor, unless we really need it. It might have sounded ok in 1930 but it doesn’t sound good today.”

While Customs would be responsible for stopping items at ports of entry, Homeland Security Investigations agents in 46 countries would be responsible for the investigation of illicit trade.

David Abramowitz, who advocated for the change as vice president of Humanity United, said the federal government will need to dedicate the resources to make sure the law is now properly enforced.

“We in civil society will have to be vigilant so that these reforms really lead to ensuring that US markets are not open to goods made with modern slavery,” he said.

Associated Press writer Margie Mason contributed to this report from Samut Sakhon, Thailand.