Both the current illegal production of drug-crops and the efforts of the War on Drugs to eradicate illegal substances at their source has led to significant harms to the environment.
US anti-drug efforts have often focused on those at the bottom of the drug chain, namely producers and farmers of such crops as the coca leaf. Plan Colombia, which began in 2000 and was a US-financed anti-narcotics effort based upon a military and eradication solution, advocated the aerial-spraying of pesticides on coca growing farms. Whilst numerous sources have shown the unsuccessful effects that this programme has had on coca supply, fumigation has killed the crops and animals of poor peasants and even resulted in human poising incidents.
After aerial-spraying began in certain parts of Colombia, many residents began to complain of various illnesses. One study examined the case of the Putumayo region of Colombia and complaints about the effects of fumigation included: respiratory problems, gastrointestinal complaints, skin problems (including rashes, burns, welts and boils), fever, dizzy spells, eye problems and other ailments including hair loss and vaginal haemorrhaging . Even those farmers that have switched to alternative crops have had their fields sprayed due to such factors as wind changes and spray planes flying extremely high – to avoid being shot by guerrillas defending the fields – which renders accuracy levels very low.
However for all the problems that it causes, fumigation does not achieve its aim. Despite spraying glyphosate (a potent herbicide) in Colombia since 1986, coca cultivation has increased by over 500 per cent . Traffickers often move coca fields to avoid fumigation, causing vast damage to the environment through deforestation.
The high value of the crop and the poverty of the growers mean that starting-up the cultivation and supply in other areas is inevitable. Farmers in Bolivia, Mexico or Afghanistan cannot be persuaded to stop growing illegal crops because their demand is too high and alternatives are nowhere near as profitable.
The ‘Balloon Effect’:
Another significant consideration within this category is the ‘balloon effect’. This is when fields are sprayed and growers just move to another area and replant there. Law enforcement efforts in Colombia have pushed traffickers and growers into Ecuador and Peru, according to the 2011 United Nations Office of Drugs and Crime (UNODC) Report . In the language of the United Nations Development Programme:
The need for a new approach to Drug Control is urgent.
 Departamento administrativo de Salud, Putumayo subdirección de Salud Pública, ‘Impacto de las fumigaciones aéreas con glifosato en el Putumayo’, Putumayo, Colombia, 2005
 Grace Livingstone, ‘America’s Backyard: The United States & Latin America From the Monroe Doctrine to the War on Terror’, Zed Books, 2009, p.178
 UNODC, World Drug Report 2011
 United Nations Development Programme Colombia. ‘Taking Narcotics Out of the Conflict: The War on Drugs’ in National Human Development Report, 2003, p.8