Long-standing drug policies backed by the United Nations and financed by the United States have not only failed to slow global drug trafficking, they may also be driving widespread environmental degradation and accelerating climate change.

In a report published by the Open Society Foundation, researcher Kendra McSweeney calls for a broad reconsideration of conventional "cat and mouse" policies that have driven growers, producers, and traffickers into new frontiers, causing deforestation and inviting chemical contamination into some of the most sensitive ecosystems on the planet, including national parks and indigenous reserves.

"Among the many forms of collateral damage from drug policy that we already know about, we want the global community to know about the widespread harms to the environment," said McSweeney, a geographer at Ohio State University.

The findings come ahead of the United Nations General Assembly Special Session (UNGASS) on drugs, slated to take place in April of next year. Drug policy experts hope that the session, which aims to move "towards an integrated and balanced strategy to counter the world drug problem," will review the collateral damage caused by failed policies that have largely focused on eradication and interdiction campaigns.

Over the past 40 years, the United States has spent more than $1 trillion combatting illicit drug trafficking across the globe, focusing on tactics of eradication and interdiction. Despite the high economic and human cost of these policies, drug use has remained relatively stable and drug revenues continue unabated. Estimates vary widely, but the Organization of American states says $320 billion is generated annually by the illegal drug trade.

While the environmental impacts of drug crop cultivation have been discussed in policy circles — the United Nations Office of Drug Control (UNODC) recognized that the herbicides and fertilizers used to grow and process coca are damaging to the environment, and more than 700,000 acres of forest were lost to coca crop cultivation between 2001 and 2013 — there has been little discussion about how drug policy itself is driving environmental degradation.

This is important, the report highlights, because UNODC policies work "in direct opposition to concurrent UN efforts to protect biodiversity, secure ecosystem services, ensure the rights of indigenous peoples, mitigate climate change, and promote sustainable development." It is a glaring institutional contradiction, McSweeney says, that should be confronted at the UNGASS session on current drug policy.

"The amount of land required to supply cocaine, marijuana, and heroin demands is quite tiny," McSweeney added. "It becomes an environmental problem because the fields keep getting destroyed, so in order to meet that demand, they have to keep moving around — drug policy keeps that cultivation mobile."

Fumigation campaigns, for example, are commonly used as a means of drug crop eradication. They have been a cornerstone of the 15-year, multi-billion dollar Plan Colombia, an aid package created by the United States to fight drug trafficking in the South American country. For years, government planes sprayed glyphosate — the active ingredient in Monsanto's Round Up — onto illicit coca crops, with notable impacts on wildlife, food crops, livestock, and the health of nearby residents.

The Colombian government vied for control of remote stretches of the country controlled by paramilitary and guerrilla groups, notably the Revolutionary Armed Forces of Colombia, who were accused of engaging in drug trafficking and terrorism. In 55 years, the civil war took the lives of an estimated 220,000 people, 80 percent of which were civilians.

"At the end of the 1990s, when the internal armed conflict was intensifying, those who denounced the environmental damage caused by the so-called 'war on drugs and terrorism' were called out by members of the government as being aids to the guerrillas," said Guillermo Ospina, a researcher at the University of Cauca, Colombia, who has studied the impacts of drug policy.

He said that this attitude has since shifted, but when the country announced a ban on the use of glyphosate earlier this year, much of the damage had already been done: between 2001 and 2014, an estimated 1,124 square miles of primary forest were lost to coca cultivation in Colombia. By 2014, coca was growing in 16 of the country's 59 national parks.

"In Colombia, they went into national parks because these were off limits for spraying," said Vanda Felbab Brown, a senior analyst at the Brooking Institute. "But in Peru, the cocaleros have been given free reign to cultivate in national parks – not merely because they faced eradication efforts, but because there was less government control."

Bolivia has successfully reduced coca cultivation despite President Evo Morales kicking the US Drug Enforcement Administration out of the country in 2008.

Beyond drug producing zones, as interdiction tightens security on known routes, traffickers push deeper into remote areas. These transit areas, according to the report, are sites of ongoing environmental damage. And given the current drug prohibitions, the illegal profits traffickers accrue are often laundered into ranching, logging, and agribusiness ventures, at an additional cost to the environment.

In other parts of the world, as in Latin America, current drug policies have often touted the promise of alternative economies. But often, according to Felbab Brown, the replacement economies that arise when the drug industry is restricted are often far more detrimental to the environment than the original trade.

In Burma, for example, when the poppy cultivation was successfully suppressed in the 1990s and 2000s, illegal logging and wildlife poaching took their place. "The two replacement economies for poppy cultivation, in this case, were vastly more detrimental than the consequences of poppy cultivation," Felbab Brown said.

The report offers concrete suggestions on how to improve current drug policy, such as including the costs of environmental degradation in drug policy decision making. It also calls for multinational agencies to explore regional solutions to the problem, citing legal drug cultivation in Bolivia. UN member states must double down on their commitments to biodiversity, offering financial support to indigenous and peasant communities, while reallocating interdiction resources to efforts to prevent money laundering in environmentally degrading rural sectors.

And, McSweeney adds, policy makers must recognize that these impacts are disproportionately displayed in the global South, where environmental damage has meant a loss of economic opportunities for local communities.

In the past, these arguments have not held weight with policy makers, but Ospina, who has worked among local communities in Colombia, is hopeful that a growing focus on the environment could help push what he sees as a slowly shifting tide in drug policy.

"Arguments related to environmental harm have not had sufficient strength to achieve significant changes in anti-drug policies in the past," he said. "But discussions of the environment have been gaining importance within the local communities, in the sense that this allows them to gain visibility and make demands in the face of abandonment by the state."

Four months ahead of the 2016 UNGASS meeting, and just days after a historic climate agreement was brokered in Paris, McSweeney is hopeful that the report will offer a new, perhaps more appealing frame for discussion.

"It adds to the mounting arsenal of evidence of how awful conventional drug policy has been at failing to address the problem, while creating terrible side effects," McSweeney said. "We have been pushing this argument for drug policy reform because the human rights consequences of drug policy haven't seemed to generate the interest that talking about the rainforest does – and if that's what will get their attention, I am happy to lay out the problem."

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