The images are disturbing.

Sitting on bare floors, their faces coated with metal particles thrown off by grinding wheels, Pakistani boys as young as 8 squat in cramped, noisy workshops where they grind, file, polish and assemble surgical instruments. The children, who often earn less than 75 cents for a nine-hour day, work without any sort of gear to protect them from the toxic metal dust or the sharp scalpels and scissors that they are manufacturing for export to foreign countries, possibly including the United States.

The child workers of Sialkot, Pakistan, captured on video footage commissioned by the International Confederation of Free Trade Unions, are the focus of a new campaign by international labor groups against the exploitation of minors in dangerous occupations.

Theirs is also the kind of work that President Clinton will seek to outlaw when he addresses the International Labour Organization in Geneva today and endorses a new convention that calls for the "immediate elimination of the worst forms of child labor." The ILO may vote on adopting the convention Thursday.

Worldwide, according to the ILO, an estimated 250 million children between the ages of 5 and 14 are "economically active." Nearly half work full time. The vast majority of working children live in developing countries -- 61 percent are in Asia -- but child labor also has become a growing problem in Eastern and Central Europe because of economic dislocations, the organization says.

According to one national survey cited by the organization, more than 20 percent of working children suffered job-related injuries or illnesses. The ILO did not identify the country.

"It's almost forced labor," said Sen. Tom Harkin (D-Iowa), a leading advocate of tougher U.S. laws against child labor. "The United States must take the lead, along with the ILO, in putting an end to it."

In advance of his speech at the ILO -- the first by a U.S. president in the organization's 80-year history -- Clinton last week issued an executive order barring federal agencies from buying products made with forced or abusive child labor.

But labor investigators say complex subcontracting arrangements and layers of outsourcing often make it difficult to trace the ultimate destinations of products such as the surgical instruments made in Sialkot, an industrial town in eastern Pakistan. In addition to local employers, they say, Western manufacturers, importers and consumers, including hospitals and other health care providers, also share responsibility for the cost-cutting that drives the use of cheap child labor.

In Sialkot, the surgical instruments industry has thus far attracted much less attention than the stitching of soccer balls, another enterprise known to employ child labor. That industry became the subject of a global campaign three years ago when embarrassed Western sporting goods manufacturers were identified as selling balls stitched in Sialkot.

According to the ILO and the Punjab Labor Welfare Department, about 7,500 children under age 14 help make surgical instruments in Sialkot, accounting for 15 percent of the town's 50,000 workers in that industry. Almost all the children toil in small workshops that perform specific tasks, such as filing and grinding, under subcontracts.

"Workers suffer frequent injuries from machinery, burns from hot metal and respiratory problems from inhaling poisonous metal dust," says a report issued this month by Public Services International, a labor group based in France. The average age of children in the industry is 12, the group says. They typically start when they are 10, although some are as young as 8, it says.

Sialkot accounts for about 20 percent of the world's production of "disposable floor instruments," such as standard forceps and scissors, and up to 15 percent of the higher-quality "theater instruments" used in surgeries, Public Services International says in a separate study. The United States is the leading market for Sialkot's floor instruments, it says.

The study lists dozens of U.S. companies that import surgical instruments from Pakistan and some of the Sialkot-based firms they deal with. However, it does not identify which companies in Sialkot employ children and cautions that the existence of a connection between a U.S. company and a Pakistani firm "does not necessarily mean that child labor is involved." But because of the prevalence of subcontracting to workshops that employ children, there is "probably a better than even chance" that any given Sialkot manufacturer has some link to child labor, the study says.

The study raised questions about contracts awarded on behalf of the Department of Veterans Affairs to two suppliers of surgical equipment that buy some of their products from firms in Sialkot. A procurement analyst for the department, Sandy Murbach, said Pakistan is not among the countries eligible to supply such products under federal contracts.

"Those companies could be getting products from Pakistan," she said, "but they may be selling them to non-federal customers."

Denied a Childhood

Complex subcontracting arrangements make it difficult to trace child labor practices in places such as Sialkot, Pakistan.

Sialkot surgical instrument industry workers

All 50,000

Subcontractors 25,000

Children 7,500*

*Children mostly work for subcontractors.

Percentage of children age 10-14 in the work force

Mali 54%

Burkina Faso 51

Niger 45

Uganda 45

Kenya 41

Senegal 31

Bangladesh 30

Nigeria 26

Haiti 25

Turkey 24

Ivory Coast 20

Pakistan 18

Brazil 16

India 14

China 12

Egypt 11

SOURCE: International Labour Organization

CAPTION: A child assembles surgical scissors in a workshop in Sialkot, Pakistan.

CAPTION: A child in Sialkot's surgical instruments industry works at a grinding wheel in a cramped shop.