Workers from more than 40 charity organizations exploited refugee children and women in West Africa by trading food for sex, according to a leaked report — that the United Nations has known about for 16 years.

The disturbing scandal is laid out in an 84-page report produced in 2001 by researchers for the United Nations High Commissioner for Refugees and Save the Children working at refugee camps in Guinea, Sierra Leone and Liberia.

The report was handed over to the UNHCR in 2002 but only a summary of the allegations was published.

Identified in it are 40 organizations “whose workers are alleged to be in sexually exploitative relationships with refugee children,” according to The Times in the UK, which obtained a copy of the full report.

Aid workers were “among the prime sexual exploiters of refugee children, often using the very humanitarian assistance and services intended to benefit refugees as a tool of exploitation.”

They allegedly traded basic needs — like food, oil, access to education and plastic sheeting for shelters — for sex.

Women at a camp in Guinea told the researchers, “In this community, no one can get corn soya blend without having sex first. They say, ‘A kilo for sex,’” the Sun reported.

“These NGO workers are clever, they use the ration as bait to get you to have sex with them,” a teenage girl in Liberia added.

Some families felt compelled to offer their young daughters as a way to “make ends meet,” the report found.

Many of the organizations implicated were small and local but 15 were international, including UNHCR, the World Food Programme, Save the Children and Merlin.

Also named were Médecins Sans Frontières, Care International, the International Rescue Committee, the International Federation of Red Cross Societies and the Norwegian Refugee Council.

The researchers said some of the allegations in the report couldn’t be fully verified and needed further investigation.

But they noted, “The number of allegations documented, however, is a critical indicator of the scale of the problem.”

Allegations leveled against 67 people were provided to senior UNHCR officials in “confidential lists” but fewer than 10 were dismissed and none were prosecuted, The Times said.

The UNHCR notified all of the charities about the allegations and sent UN investigators who identified 43 separate cases in west Africa.

The UN said it had implemented “specific preventative and remedial actions.”

In a 2005 interview, UN High Commissioner for Refugees Ruud Lubbers downplayed the report.

“We have to find concrete evidence,” he said at the time. “It’s very scarce. So the idea of widespread sexual exploitation by humanitarian workers, I think it’s simply not a reality.”

Christine Lipohar, a Save the Children official who co-authored the report, was “frustrated and annoyed” at Lubbers’ response.

“Good systems for preventing and responding were developed on paper, but have not been effectively and consistently rolled out in all locations; so implementation . . . is often reliant on individuals committed to the issue,” she said.

The UNHCR said it had a “a zero-tolerance policy, which means that every possible report or allegation of sexual exploitation, abuse or harassment by UNHCR or partner personnel is thoroughly assessed and if substantiated leads to sanctions, including summary dismissal.”