Marisa has been locked in a small, windowless room for the past three days. The 14-year-old girl is angry but says that she understands why her mother, Blanca, has refused to let her out. “If I walk out that door, I’ll smoke paco.”

The use of paco, a smokeable cocaine residue, has risen in the slums of Buenos Aires, is behind a drugs epidemic and drug-induced violence. Doctors have said that it is more addic-tive than crack and can cause brain damage within six months. It is so toxic and low-grade – it is made from the chemical leftovers from when coca leaves are turned into cocaine – that traffickers used to throw it away.

“You won’t find a young person who doesn’t smoke paco here,” Blanca said. “It is tearing our community apart.”

Marisa and Blanca live in Ciudad Oculta, a violent, overcrowded, sprawling slum on the outskirts of Buenos Aires. Here the sweet, thick smell of paco wafts out of almost every shack and from every street corner.

Marisa said that all her friends smoked paco. Until her mother locked her up she used to smoke up to 30 hits a day and robbed to fund her habit.

Outside her home some friends of Marisa were on their way to buy the drug. All the children had sunken eyes and wrinkled faces, their small bodies ravaged by the chemicals they inhale when they suck up the white clouds of smoke. Sulphuric acid, kerosene, rat poison and crushed glass are just some of the ingredients.

A few hits of paco, which is known as the poor man’s drug, cost about £2.

In an attempt to control its production the Argentine authorities made it more difficult to export the chemicals needed to make paco, but the traffickers simply moved their laboratories to Argentina.

Plan Colombia, a multimillion-pound initiative backed by the US, put pressure on traffickers, who are now turning to the South American market. Some experts believe that the “No to cocaine, yes to coca” policy of Evo Morales, the Bolivian President, which led to a lifting of restrictions on growing coca plants, is adding to the influx.

“The problem is that Evo Morales doesn’t have the capacity to control the huge territory of Bolivia where coca can be produced for illegal means, so the chances of failure are quite high,” Giovanni Quaglia, the regional representative of the UN Office on Drugs and Crime, said.

The United Nations says that the number of paco addicts in Argentina has tripled in the past two years. The Government say that there are about 85,000 paco addicts but many believe that is a conservative estimate.

There are now signs that the drug is making its way into the city.“If the Government doesn’t act soon we’re going to have a serious crisis on our hands,” Eduardo Kalina, one of the leading Argentine specialists on drug addiction, said.

For Blanca the situation is already out of control. “I can’t lock my daughter up for ever. What can I do? It’s too late for us here. Nobody cares if the poor die,” she said. “Maybe when the rich start dying the Government will do something.”

A report on paco by Ramita Navai can be seen on More4 News at 8pm tonight.

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