CARE International said on Wednesday a household assessment of more than 2,200 Syrian refugees showed 90 percent of them were living in debt to relatives, landlords, shopkeepers and neighbors.

The cost of rent for the refugees from the devastating three-year war in Syria had increased by almost a third in the past year, according to the CARE study.

"The insecurity to provide for their families causes increasing levels of stress and sets women at risk of sexual exploitation. In many cases, young sons become the family's breadwinner to make ends meet," the organization said.

The study showed that only 52 percent of Syrian refugee boys were attending school, compared with 62 percent of girls.

"Three years after the Syria crisis started, refugee families are becoming more and more destitute," said Salam Kanaan, CARE's director for Jordan.

"The longer they live in neighboring countries, the more financially vulnerable they become. Families have fled months or years ago, they do not have any savings anymore."

Jordan is home to more than 500,000 Syrian refugees.

More than 80 percent of them live in poor urban areas or on the outskirts of cities, often in inadequate dwellings, informal tented settlements and makeshift shelters, CARE said.

The refugee families have to spend an average of $260 (188 euros) per month for rent.

CARE said 36 percent of the families registered with the organization were headed by women.

"They have fled without their husbands who are either still in Syria, injured or have been killed. They have to take care of their young children and older relatives, but have difficulties to generate income," it said.

CARE said the social and psychological impact of the war on families is increasingly worrying.

"Especially refugees who have been displaced for years and have no more assets, worry about how they can cover their monthly expenses and deal with medical emergencies," said Kanaan.

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