WASHINGTON — A Labor Department study released Monday concludes that use of child labor in developing countries to make consumer goods, including apparel, for sale in the U.S. is prevalent and provides fodder for passage of a Senate bill targeted at blocking such trade.

The study, “By the Sweat and Toil of Children: The Use of Child Labor in American Imports,” says employment of children under the age of 15 is common in the garment industries of South and Southeast Asia, Africa and Latin America, although it notes only 5 percent of total foreign employment in export industries involves children.

“Conditions in these industries range from crowded garment factories, where the doors are locked and the children work for 14 hours, to small dusty earthen huts, which can seat four children to a loom, knotting carpets in a pit for hours on end,” according to the study, concluding that child workers are typically found at subcontractors, not large manufacturers.

The 185-page review of worldwide child labor practices was commissioned by Sen. Tom Harkin (D., Ill.), who has seen his Child Labor Deterrence Act stalled in Congress due to lack of supporting evidence. The act would ban importation of goods made by children under the age of 15. Retailers and vendors that violate the act would be subject to large fines and criminal penalties.

On the heels of the study’s release, the Senate Labor Subcommittee Wednesday is scheduled to hold a hearing to scrutinize imports of consumer goods made by children. The subcommittee’s chairman, Howard Metzenbaum (D., Ohio), has been an advocate of requiring retailers and vendors to certify their merchandise has not been made by children.

Scheduled as witnesses at the hearing are a 14-year-old Honduran girl employed at an apparel factory and a 19-year-old woman from Bangladesh who began work in the garment industry at age 11. A spokesman for the senator could not identify where the two women work.

Harkin said the Labor Department study is a “first step” in identifying industries employing children and highlights the need for passage of his bill, which is strongly supported by organized labor. Labor has long complained of U.S. workers having to compete with imported goods made in violation of international labor standards.

“I do not believe that U.S. consumers would willingly buy products made by child labor. But consumers can’t always know when a product was made by child labor,” Harkin said.