Geneva - Forced labour produces illegal profits of $150bn a year, the United Nations' labour agency said on Tuesday as it appealed for global eradication of the abuse.
The report by the International Labour Organisation offered the agency's fullest picture yet of an underground economy built on the involuntary toil of an estimated 21 million workers. It found that nearly two-thirds of the estimated profits, $99bn, come from sexual exploitation, including prostitution and pornography.
Women were most commonly the victims of forced employment in sex-related trades and domestic chores, while men and boys were more commonly exploited in agricultural, mining and construction work, it found.
The director-general, Guy Ryder, said the report highlights the need "to eradicate this fundamentally evil but hugely profitable practice as soon as possible". He said many governments, employers and labour unions all needed to do more to stamp out abusive employment practices, including outright slavery.
The report said the world's most developed countries, including the entire European Union, accounted for nearly a third of the illegal profits, $46.9bn, while the rest of the Asia Pacific region generated $51.8bn. Other regions had much lower totals.
It found that exploited workers generated much more money per head for their employers in the richest countries. Estimated profits in developed countries reached $34 800 per worker, while Africa registered the lowest per-capita profit rate of $3 900.
Worldwide, it found sexually exploited workers produced by far the highest profits for their employers: $21 800 per worker, versus just $2 500 on average for each farm labourer, and $2 200 for each domestic worker.
Ryder said governments needed to improve welfare support "to prevent households from sliding into the poverty that pushes people into forced labour", he said. "We need to improve levels of education and literacy so that household decision-makers can understand their own vulnerability to forced labour and know their rights as workers."
The agency's previous report on the topic of forced labour, in 2005, estimated worldwide profits at $44bn. But that report focused chiefly on sex-related work and agriculture, whereas Tuesday's report expanded its analysis greatly to include miners, construction workers, maids and au pairs, and other jobs involving employer coercion and little pay.