London - A picture campaign highlighting the devastation caused in Colombia by the production of cocaine for markets in Europe and America came to London on Wednesday before heading across Europe.

Shared Responsibility, a collection of photographs with captions showing the wholesale destruction of the rainforest for plantations of coca plants, aims to raise the guilt factor among cocaine users.

"Cocaine kills Colombians, it hurts Colombians and massively destroys the environment," Colombia's Vice President Francisco Santos said at the opening of the campaign in Trafalgar Square.

"Every gram of cocaine you inhale destroys four square metres of rainforest," he added.

Not only are three hectares of rainforest cleared for every one hectare of coca plants, but the chemicals used in the cultivation of the plants and the production of the drug also cause major water pollution.

"The real price of cocaine is not just among communities and on the streets here, but in communities and on the streets of Colombia," said British Home Office Minister Vernon Coaker.

The campaign says 2.2 million hectares of forest have been cleared for cocaine production, adding that the wholesale destruction not only puts at risk the lives of thousands of ordinary Colombians but also vast quantities of wildlife.

It says Colombia's forests are home to 13 percent of the world's amphibians, 10 percent of sweet water fish, nine percent of mammals and six percent of reptiles.

Not only that but the forests is a vital lung for the world and its destruction for drugs therefore has global consequences for climate change.

The US Department of Justice's National Drug Threat Assessment said 144,000 hectares of land was under coca cultivation in Colombia in 2005, producing 545 tonnes of pure cocaine -- 70 percent of the region's total.

Eradication campaigns in Colombia, with clearance teams on the ground facing the threat of landmines, had succeeded to a certain extent but had also resulted in farmers moving to non-traditional areas that were harder to find and reach.

There had been some successes with farmers switching to cocoa, coffee, fishing and beekeeping, but much more was needed to be done, said Coaker, praising the cooperation between Britain and Colombia.

"I hope this campaign will make an impact on the way people think and behave and the individual decisions they make and they recognise the problems that can accrue to the innocent people of Colombia," he said.

(Editing by Matthew Jones)