Report: There are 40 million slaves worldwide, most are women and girls

A United Nations agency warns 40.3 million people across the globe were subject to some form of modern slavery in 2016. Among them, about 28.7 million — or 71% — were women or girls forced into sex, marriage or labor.

The 2017 Global Estimates of Modern Slavery report released Tuesday found modern slavery in every region of the world. The report didn't specify how many of those victims were in the United States during 2016, but a Walk Free Foundation index estimated that number to be about 57,700.

The report was compiled by the UN's International Labour Organization (ILO), the Walk Free Foundation and the International Organization for Migration. Modern slavery has no legal definition but includes human trafficking, forced labor, debt bondage and forced marriage. Put simply, the report said modern slavery is "exploitation that a person cannot refuse or leave because of threats, violence, coercion, deception, and/or abuse of power."

The majority of the world's modern slavery in 2016 took the form of forced labor, which accounts for about 24.9 million of modern slavery victims. These are people being forced to work in factories, farms and elsewhere under threat or coercion. It also includes the sex industry. The rest, about 15.4 million people, were living in an unconsented forced marriage, which often included labor.

Andrew Forrest, chairman of the Walk Free Foundation, said the number "shames us all."

"This speaks to the deep-seated discrimination and inequities in our world today, coupled with a shocking tolerance of exploitation," he said.

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The regions most prone to modern slavery were Africa, Asia and the Pacific. And Europe and Central Asia.

About a quarter of modern slavery victims were children, including those forced to marry as children and those in sexual exploitation. About 1 million children were victims of commercial sexual exploitation in 2016 and 3.8 million adults were in forced sexual exploitation. Women and girls accounted for 99% of sexual exploitation victims and 88% of forced marriage victims.

The ILO also released its Global Estimates of Child Labour report, which estimates about 152 million children worldwide subject to labor.

The modern slavery report said ridding the world of slavery will require interventions on the economic, cultural, legal and social forces assisting slavery.

"This has to stop," Forrest said. "We all have a role to play in changing this reality — business, government, civil society, every one of us."

Follow Sean Rossman on Twitter: @SeanRossman