Thousands of children working in Malawi‘s tobacco fields are exposed to dangerous levels of nicotine and tobacco dust, the equivalent of smoking 50 cigarettes a day, a children’s rights organization said Monday.

More than 78,000 child laborers, some as young as five, suffer from severe health problems caused by daily skin absorption of up to 54 milligrams of dissolved nicotine, Plan International said in a report on its website. They work for up to 12 hours a day without protective clothing on tobacco estates across the southern African country, and are paid as little as 2 cents an hour, it said.

The youngsters described how they have trouble breathing, suffer headaches and abdominal pains, and even cough blood as a result of hard labor. One child told researchers: “You reach a point where you cannot breathe because of the pain in your chest; then the blood comes when you vomit.”

The report also claims widespread abuse by plantation managers, including beatings and sexual abuse. Some were not given enough food to eat.

Malawi is the fifth largest producer of tobacco in the world and relies on sales of the leaf for 60 percent of its export earnings.