All Coked Up: The Global Environmental Impacts Of Cocaine

"Sol Prendido" for Borderland Beat

* Cocaine is one of the most widely used illicit drugs in the world, consumed by an estimated 20 million people in 2019, mostly in North America and Europe.

* Production, transit and consumption of the drug are exacting a heavy environmental toll, impacting tropical forests, freshwater and estuary ecosystems. Some of these effects, such as pollution impacts on eels and other aquatic species, have been documented, but most are still poorly understood, with many unresearched.

* Indigenous peoples are often at the front lines of criminal gangs’ activities in producer and trafficking countries. Often, when new narco-trafficking transport routes are established, like those in Central America, those same routes are used for other criminal activities such as wildlife and weapons trafficking.

* Researchers argue that detaching the environmental harm caused by the cocaine trade from the long-lasting war on drugs is not possible. Solutions implemented to deal with the drug problem, such as the aerial spraying of illegal coca crops, while locally effective in curbing illegal cultivation, also cause deforestation and biodiversity damage.

The environmental impacts of cocaine have long been known. Studies raised alarm bells in the 1990s over narco-driven deforestation, soil degradation and pollution in Latin America. Today, the impacts all along the illegal drug supply chain are even better understood and documented, but remain underrecognized and underreported.

Meanwhile, the titanic struggle continues between those determined to curb illegal drug use and the shadowy forces intent on producing, trafficking and consuming the quintessential party drug snorted by millions, as they propel biodiversity loss, adverse land-use change, waterway contamination with toxic chemicals, and adjacent criminal industries such as wildlife trafficking and gold mining — even contributing to climate change.

From source nations to consumer countries, the infamous white powder known as coke, or blow, is leaving a trail of environmental destruction that is contributing to the destabilization of Earth’s “safe operating space,” vital to keeping our planet habitable.

An estimated 20 million people used cocaine in 2019. Image by Jernej Furman via Flickr (CC BY 2.0).

Chasing coca: By the numbers

In 2019, an estimated 234,200 hectares (578,720 acres) of coca were grown in Bolivia, Peru and Colombia. That was down 5% from the year before, but still resulted in major environmental impacts. Back in 1985, Peru was the global hub of coca production, growing around 65% of the global total, with Bolivia at 25% and Colombia just 10%. Years of aggressive anti-trafficking efforts in Peru and Bolivia forced the cultivation shift to Colombia — one of the world’s most “megadiverse” nations, hosting close to 10% of Earth’s biodiversity.

The latest figures released by the U.N. Office on Drugs and Crime (UNODC) and the Colombian government’s monitoring program show 143,000 hectares (353,400 acres) of coca in Colombia in 2020, a decline for the third year in a row. But despite less coca being grown there, 8% more cocaine was produced, totaling approximately 1,228 metric tons. More efficient crop management, along with mega labs that churn out vast quantities of coca paste and cocaine, are thought to be behind this increase.

Statistics from the U.S. Office of National Drug Control Policy paint a different, more concerning picture, estimating 245,000 hectares (605,400 acres) of coca grown in the same year.

But coca and cocaine production are just one part of a complex web of problems placing Colombia’s biological riches at risk. Among the most severe is deforestation: In 2020, nearly 13,000 hectares (31,100 acres) of Colombia’s forests were felled to support coca cultivation. That’s 7.54% of the country’s total 171,685 hectares (424,243 acres) of tree loss from all activities, including cattle ranching and agricultural expansion.

The same study found that a further 22.4% of deforestation (38,449 hectares or 95,010 acres) occurred within 1 kilometer (0.6 miles) of coca plantations and was due to linked activities including the construction of clandestine airstrips, and to tangentially related activities, such as coca production’s contribution to the agricultural frontier’s advancement.

Two women harvesting coca in South America. 

Colombian manual eradicators destroy coca fields in 2018. Image by the U.S. Government Accountability Office via Wikimedia Commons (Public domain).

Coca as a cause of deforestation

Parsing out the precise causes of all this additional deforestation is complicated, says Liliana Davalos at Stony Brook University, who has studied the links between coca and deforestation for 20 years. “I wanted to discover whether it was happening in places where deforestation wouldn’t happen otherwise,” she says. “The answer is, it depends.”

The degree to which coca production directly causes deforestation is very locally specific, she explains. “In the Andean region of Colombia, for instance, which we’ve studied closely, in places like San Lucas, we see that coca plays a disproportionate role where no other crops are grown, or [there are] no pastures, or a much lower level of pastures … There are huge effects in the Andean upland region and great, great potential for damages to biodiversity based on the spatial database we have.”

But at lower elevations in the Amazonian region, the picture is less clear. “We find that once we take into account social factors of [human] migration, growth, [and] construction … we really don’t find an impact from cocoa cultivation … in the Amazon, coca is more of a passenger than a driver of the process — which is a process of frontier deforestation, incorporating vast tracts of land into the financial system.”

Cocaine production does other harm. It releases toxic chemicals into the environment via processing labs. Chemicals commonly used by the mega labs include toluene, sulfuric acid, acetone and gasoline. It takes 284 liters of gasoline to make 1 kilogram of cocaine, or about 34 gallons a pound, and a significant portion of Colombia’s gasoline supply is likely diverted to produce coke. And it only takes one part of dumped petrol to contaminate 750,000 parts of groundwater.

In addition, estimates suggest up to 3.5 million metric tons of chemicals per hectare per year, or about 1.6 million tons per acre, are used in the processing of cocaine, resulting in soil degradation and more water pollution. A 2014 survey determined that 98.7% of coca farms also use insecticides or fungicides, 92.5% apply chemical fertilizers, and 95.5% use herbicides. Together with cocaine itself — found in Amazon Basin waterways — the potential toxic impact of production is likely vast, though poorly understood or monitored.

Police burn a coca lab in Tumaco, Colombia, 2008. Image by Colombian National Police via Flickr (CC BY-SA 2.0).

Aerial spraying raising questions still

Combatting cocaine growers has also been environmentally detrimental. Aerial spraying with the controversial herbicide glyphosate, popularly known as Roundup, is argued by critics to have left a legacy of ecosystem and human harm.

Long encouraged and funded by U.S. drug enforcement, the practice that began in Colombia in 1994 was banned there in 2015 due to concerns over its role as a carcinogen. But the current government under President Iván Duque is pushing to reintroduce spraying to tackle the drug problem. This March he even approved the use of low-flying drones for that purpose. While considered potentially effective in the short term at reducing coca crops in specific areas, such a reinstatement would not only pollute, but perpetuate other troubles.

“Aerial spraying [sings] the siren song that it eliminates coca cultivation rapidly,” explains Vanda Felbab-Brown, a senior fellow at the Brookings Institute. “But it does so in ways that are problematic from [an] environmental and human public health perspective.”

She compares the ballooning proliferation of coca cultivation in Colombia to the situation elsewhere. “We’ve got countries [like Peru and Bolivia] that haven’t applied that policy, and they have their wedges of coca that … just stay put,” she says. Then, “We have a country [Colombia] that, by using this aerial fumigation technique seems to be associated with this giant explosion [of impacts] in every ecosystem.”

Last year, the U.S. and Colombian governments announced a new counternarcotics strategy, which includes an environmental protection aim alongside drug supply reduction, rural security and development goals. “The United States will assist the Colombian government in its efforts to monitor and counter these environmental crimes that sustain and fuel narco-trafficking groups that have a profoundly negative impact on Colombia’s environment,” states a U.S. White House press release.

This focus on environmental crime has already manifested itself in Operation Artemis, a military operation in Colombia for reducing deforestation. In addition, a recently passed bill promises harsher drug production penalties, including jail time. However, concerns are that such actions will predominantly impact Colombia’s small-scale farmers.

Aerial spraying of pesticides. Spraying with the controversial herbicide glyphosate, popularly known as Roundup, is argued by critics to have left a legacy of ecosystem and human harm. Image by amissphotos via Pixabay.

A plague on parks, wildlife and Indigenous people

Colombia’s national parks are impacted by coca growing, with an estimated 7,214 hectares (17,826 acres) in 12 federal preserves seeing illegal production in 2020, an increase of 6% over 2019. Catatumbo-Barí is the worst affected, suffering deforestation, lawlessness and a host of issues related to cocaine trafficking. Other parks and protected areas affected include Sierra de la Macarena, the Nukak Reserve and Paramillo Massif.

“With coca in national parks, the production is not that big,” explains Ana Maria Rueda, a senior investigator at Fundación Ideas para la Paz, a Colombian think tank. But “what they’re [seeing is] territorial control [by criminals], for example, related to traffic routes to take cocaine out of Colombia.”

This expansion of coca growing and cocaine processing on protected lands presents a risk to biodiversity. An update to Colombia’s Red List Index in 2020 implicated coca cultivation and its contribution to forest loss and habitat fragmentation as increasing the extinction risk to bird species, including the yellow-knobbed curassow (Crax daubentoni), plumbeous forest falcon (Micrastur plumbeus), scarlet-breasted dacnis (Dacnis berlepschi), and plate-billed mountain toucan (Andigena laminirostris). Of the 13 species that saw their conservation status deteriorate, eight were affected by illicit cocoa expansion, the report notes.

Drying coca leaves in Cruz Loma village near Coroico, Bolivia. 

Paramillo National Park in Colombia. While coca grown in 12 protected areas in 2019 represents only a fraction of the nation’s total crop, penetration into national parks poses a biodiversity threat and opens up conserved areas to further exploitation. Image courtesy of Agencia Prensa Rural via Flickr (CC BY-NC-ND 2.0).

Indigenous lands and peoples are also being gravely affected. Nearly 50% of Colombia’s coca is grown in special management zones, including Indigenous lands, traditional Afro-Caribbean communities, national parks, and other areas of environmental significance.

That criminal activity has made Colombia one of the most dangerous places on Earth to be an environmental rights defender, with 17 lethal attacks directed against activists supporting coca crop substitution programs in 2020. In the Peruvian Amazon, cocaine production and trafficking threatens the lives and livelihoods of Indigenous peoples, including the beleaguered Shipibo-Conibo along the Ucayali River.

“We’ve really seen an expansion in recent years of threats and killings of community leaders in the Peruvian Amazon. I won’t say that all of them are directly related to drug mafias,” says Andrew Miller, of Amazon Watch, an NGO. “But I think a number seem pretty obviously connected to this broader struggle for control over the territory.”

According to the Peruvian government, the region of Valle de los Ríos Apurímac, Ene y Mantaro (VRAEM) accounted for 43% of coca grown in the country in 2020, out of a total illegal crop of 61,777 hectares (152,654 acres). Other Peruvian regions have seen increases too. “[W]e’re working with communities, in … Ucayali and Huanaco. 

The Indigenous groups there say ‘we’re the new VRAEM … where the coca production is exploding,’” says Miller.” Mongabay Latam last year identified 16 Indigenous communities threatened by deforestation due to drug trafficking in Ucayali alone.

The plate-billed mountain-toucan is native to Ecuador and a portion of Colombia’s Nariño department. Coca cultivation in the region is considered one of the threats to the species’ survival in Colombia. Image by Ben Tavener via Flickr (CC BY 2.0).

Narco-trafficking causing deforestation and degradation

In the 1980s and early ’90s, cocaine flowed from South America to the U.S. through the Caribbean. As interdiction efforts shut down trafficking routes there, the drug was routed through Central American countries in transit to Mexico. By 2011, an estimated 60% of cocaine moved via Central America by land, sea and air, taking an environmental toll its forests and protected areas.

A 2022 study found that the Maya Biosphere Reserve lost as much as 234,612 hectares (579,739 acres) of forest between 2000 and 2018. It is one of Guatemala’s most important biodiversity hotspots. Forest loss was particularly severe on the reserve’s western side, says study author Jonathan Vidal Solórzano, which could have consequences for iconic endangered species such as the jaguar.

“The ideal scenario would be to have large areas where these jaguars can live and also … corridors so they can move from Guatemala to Mexico,” he explains. But nowadays “there’s practically no forest cover or normal, old-growth forests [on the Guatemalan side of the border]. 

There’s not so much connectivity as there used to be.”

“It is worth noting that in Guatemala, 27 of the 86 [protected areas] lost over 30% of forest cover during the period analyzed, and eight lost over 50%,” the study notes, with Laguna del Tigre National Park, for example, losing 93,858 hectares (231,928 acres). “Something has to change, particularly how protected areas with large deforestation rates are managed,” says Solórzano.

The Maya Biosphere Reserve in Guatemala. Large-scale deforestation in the region has been linked, in part, to narco-trafficking, say experts. Image courtesy of CIFOR via Flickr (CC BY-NC-ND 2.0).

While researchers stress that tying drug transport directly to land cover change is complex, and that tracing both direct and indirect impacts is not always possible, studies are connecting those dots. Research in 2017, for example determined that 15-30% of deforestation in Nicaragua, Honduras and Guatemala was linked to narco-trafficking. 

This figure rose to as much as 30-60% in protected areas. These included Guatemala’s Maya Biosphere Reserve and Honduras’s Rio Platano Biosphere Reserve. Those statistics, says Kendra McSweeney, professor of geography at Ohio State University and part of the study team, are likely underestimates.

McSweeney and other scientists see two links between cocaine trafficking and land-use change, what they describe as narco-deforestation and narco-degradation. In the first instance, forests are cut to make way for clandestine airstrips. That land is subsequently converted to cattle pasture to launder money and permanently claim territory. An influx of destabilizing cash may then follow, creating a synergy for the appearance of other industries, both licit and illicit. This ramps up further degradation and development.

A study released last year found that “large-scale sustained forest losses” of 713,244 hectares (1.76 million acres) in Guatemala and 417,329 hectares (1.03 million acres) in Honduras “correspond with areas undergoing shifts in control towards large landowners, often related to narco-trafficking.”

“I don’t think that it’s an overstatement to say that drug trafficking is one of the environmental concerns for Central America,” says Jennifer Devine, at Texas State University, who researches the environmental impacts of narco-trafficking in Central America. “Not just because of narco-cattle ranching, but because drug trafficking undermines systems of governance throughout the region.”

The weakening of local governance generates myriad criminal problems, including “land grabbing in protected areas, infill of wetland areas, forest fires [set by land grabbers], illegal logging, mangrove degradation, timber poaching, flora and fauna trafficking, gold mining, and roadbuilding,” Devine and others wrote in a published paper in 2020 examining the widespread impacts of drug trafficking going beyond deforestation.

Drug-trafficking organizations are implicated in the trafficking of other illicit goods, such as illegal timber. Image by quapan via Flickr (CC BY 2.0).

“What’s really concerning is that drug trafficking environmental impacts are affecting protected areas,” says Devine, with laundered narco-capital and illicit ranching “infiltrating forests which should be protected as being ecologically and culturally vital.”

But researchers Devine and McSweeney stress that decoupling the environmental and human impacts of the “war on drugs” is simply not possible. “What’s driving land-use change, what’s driving deforestation, is the cat-and-mouse game of interdiction,” says Devine. “It’s really important to remember that the approach to military interdiction is in large part responsible for a lot of the environmental impacts we see, including glyphosate being used in Colombia, [with] impacts on waterways, all the way to narco-cattle ranching in Central America.”

Today, Panama and Costa Rica are becoming important cocaine trafficking nodes, with the lucrative European market as the final destination. The two nations accounted for 80% of drug seizures in Central America in 2021.

This shift occurred over the past decade, says Nicholas Magliocca, assistant professor of geography at the University of Alabama. Traffickers are regularly using Costa Rica’s Osa Peninsula, on the country’s southwestern coast, as a transit point — a region known for its biodiverse Corcovado National Park. While most drugs are thought to be shipped via maritime routes, air transport is also being spotted. “We’re starting to see some more of these clandestine airstrips show up,” Magliocca says.

Costa Rica’s attraction to traffickers is partly based on its legal maritime network, which can be exploited to move product. Late last year, for example, 1.2 metric tons of cocaine shipped in a container of bananas was seized in the United Kingdom.

Illegal airstrips within the Rio Plátano Biosphere Reserve in eastern Honduras. Image courtesy of Planetscope/Google Earth.

A question of carbon and equity

Narco-driven deforestation and associated carbon emissions are “massive,” notes Magliocca. But for him, the issue is also one of equity, because it is Indigenous peoples and traditional communities that are predominantly impacted by the interdiction game played between traffickers and law enforcement.

A recent study led by Magliocca found that when interdiction efforts in Central America forced traffickers to shift from one route to another, Indigenous lands were often a first choice. “Protected areas and Indigenous territories offer that kind of contested land governance, marginalized populations, and remoteness that facilitate these operations. So they’re always going to be very attractive.

“Unless you address those equity issues, and empower these populations, then you’re not going to tackle the environmental sustainability issues,” argues Magliocca.

A similar scenario is seen in producer countries such as Peru, according to Miller, with seizure of Indigenous lands by narco-traffickers, ranchers and others often tied up in a wider fight for recognition of land rights and land titles. “The more immediate arguments that [these rural peoples] have been making is that the [ancestral land] rights of … local communities need to be respected,” he says.

That lack of respect is also apparent in Colombian national parks, where drug enforcement often involves the removal of long-established rural inhabitants from protected areas; a practice that isn’t working, Rueda says. She suggests that a window of opportunity now exists for the government to enter into agreements with communities located in, or around, parks, providing traditional people with alternative sustainable livelihoods linked to conservation.

“It’s all about moving towards the inclusion of the environmental approach within alternative development,” Rueda says. “This is a social issue and we’re [erroneously] dealing with it as a criminal issue.”

Coca plantation on a hillside near Caranavi, western Bolivia. Image by Neil Palmer/CIAT via Flickr (CC BY-SA 2.0).

Branching out

In Mexico, drug-trafficking organizations have been traced to environmental crimes such as illegal logging. Likewise, they’ve entered into legal businesses to invest and launder illicit profits — including the lucrative avocado market, for example — causing further forest loss and pressure on freshwater. Recent research by Felbab-Brown highlights growing connections between Mexican drug-trafficking organizations and wildlife trafficking to China.

“Oftentimes, the linkages between the cartels and wildlife trafficking are exaggerated,” she states. But based on field research, that’s not the case in Mexico. Drug traffickers there, she found, are now mixed up in a variety of trading schemes, ranging from the legal commercial fisheries industry to the illegal trafficking of endangered totoaba, sea cucumbers and terrestrial species such as jaguars.

Narco penetration into fisheries is a well-known phenomenon, with fishing vessels often used to transit drug shipments. A 2020 report noted 292 cases of seizures on such vessels between 2010 and 2017 globally, with combined volume of 522.1 metric tons worth $16.5 billion. While this figure includes multiple illicit drugs such as marijuana and methamphetamine, cocaine made up roughly half of the seizures.

In addition, “[B]ecause of the large volumes [of drugs] being traded … the cartels are using barter in wildlife as a transfer of value between illegal economies,” says Felbab-Brown. Wildlife products, she explains, are now traded by drug-trafficking organizations in exchange for the precursor chemicals used to make synthetic drugs such as methamphetamine. The problem of synthetic drugs continues to grow year-on-year in the region. The full findings will be released in a series of reports in the coming months.

“This generates a great threat to biodiversity in Mexico,” says Felbab-Brown, especially since it has done little to curb wildlife trafficking to China.

A fully operational submarine built for the primary purpose of transporting multi-ton shipments of cocaine found near a river tributary close to the Ecuador-Colombia border and seized by the Ecuadorian Anti-Narcotics Police Forces and the military with the assistance of the U.S. Drug Enforcement Administration. Image by the U.S. Drug Enforcement Administration via Wikimedia Commons (Public domain).

Back in producer countries, drug-trafficking organizations are also linked to illicit and licit trades, including wildlife trafficking, illegal logging, and gold mining. Drug traffickers may not engage in these activities directly, but the infrastructure, routes and transport methods they create are used to facilitate these other forms of crime, says Daan van Uhm, assistant professor in criminology at Utrecht University in the Netherlands.

On the Colombia-Panama border in the Darién region, groups involved in cocaine production, such as the Gulf Cartel, branched out into gold mining in recent years. Gold mining and smuggling has been dubbed one of the easiest and most lucrative money laundering tools in the history of drug trafficking in Colombia. It also puts pressure on forests and biodiversity, and contaminates water with chemicals such as mercury.

Last year, the Gulf Cartel’s leader was arrested and the Colombian government optimistically declared the end of the country’s largest illegal drug operation. But “the majority of the networks there are operating as substructures,” explains van Uhm, who carried out field research in the Darién region between 2017 and 2019. “They are connected to each other, but they can operate independently. I can’t imagine that [the arrest] has impacts on … the organization of cocaine trafficking or on environmental-related crimes.”

Recovery of bales of cocaine jettisoned off the coast of Colombia in 2018. That year, more than 130,000 hectares (321,200 acres) of coca bush were sprayed aerially and 96,000 hectares (237,200 acres) manually eradicated, according to the Colombia Coca survey. Image courtesy of Coast Guard News via Flickr (CC BY-NC-ND 2.0).

Demand-side dilemma: Coke in the water

Cocaine’s environmental damage is less visible in consumer countries where no forests are felled to produce and transport coca — but harm is still being done. Once coke is snorted, smoked, injected or otherwise ingested, the body metabolizes most of it. But some is excreted in urine, enters directly into waterways, or passes through wastewater treatment plants that don’t necessarily remove all of it,

The study of cocaine and other illicit drugs in wastewater isn’t new. For years, this esoteric branch of science, known as “wastewater epidemiology,” has been used to investigate drug trends in cities and countries around the world.

The European Monitoring Centre for Drugs and Drug Addiction has been running such tests across the EU since 2011, tracing cocaine’s main metabolite, benzoylecgonine. The latest findings from 2020 showed some of the highest consumption in urban areas including Antwerp, Belgium; Amsterdam in the Netherlands; and Zurich, Switzerland. Similar methods have tracked drug use at public events such as music festivals and even college basketball games in the U.S.

Though the detection of drug-use trends via wastewater data is well established, what this outflow of coke means for the environment is poorly understood. But a growing number of studies have begun to shed light on this question, with troubling findings.

The European eel (Anguilla anguilla) is critically endangered, according to the IUCN Red List. Anna Capaldo, a professor at the University of Naples Federico II, Italy, and her colleagues have been studying cocaine’s effect on the species. “The damages induced by cocaine suggest that this drug affects the physiology of the eels, and potentially of all the aquatic species exposed to it,” she states.

Exposure to cocaine has been found to have damaging effects on the critically endangered European eel, with potential consequences for its survival in the wild. Image by Bernard Dupont via Wikimedia Commons (CC BY-SA 2.0).

Though this research was conducted in labs, it utilized levels of exposure that can be found in natural aquatic ecosystems, showing the potential harm. “For example, when the gills are damaged [by cocaine exposure], the eel’s ability to oxygenate blood worsens. In the same way, a damaged skeletal muscle could not support the swimming of eels during their reproductive migration to the [Atlantic Ocean’s] Sargasso Sea.”

Capaldo and her team are currently studying cocaine impacts on eel reproduction and brain function. Other studies have shown that mussels, sea urchins and zebrafish species are impacted.

An estimated 20 million people used cocaine in 2019 — about 0.4% of the world’s adult population. In North America, 6.9 million people and in Europe 5 million are thought to use coke annually. Though consumption is highest in these two regions, studies are finding traces of cocaine in wastewater globally from Barbados to Brazil. The latter treats about 43% of its wastewater, though this plummets to 5% in rural areas. Cocaine and benzoylecgonine are among the pollutants regularly emitted into the Amazon River.

“Cocaine is extremely damaging, but it does degrade relatively quickly in the environment,” explains Dan Aberg at the Wolfson Carbon Capture Lab at Bangor University in Wales. However, that quick degradation may be offset by the steady flow of cocaine residues into the environment via wastewater.

Last year, Aberg and his team investigated the presence of cocaine and other pollutants released into waterways at the Glastonbury Festival, one of the U.K.’s largest music events. Levels of cocaine released during the festival’s surge were high enough to be potentially damaging to the European eel, says Aberg. In this case, exposure was mostly due to open-field urination and a lack of wastewater treatment.

Tracing cocaine use trends in wastewater is a common practice. But how this flow impacts the environment is still being explored. Initial research, however, indicates it can be harmful to aquatic species. Image by Ivan Radic via Flickr (CC BY 2.0).

Changing the planet

Cocaine is far from the only pollutant entering waterways, estuaries and oceans. It’s part of a toxic cocktail of pharmaceuticals, heavy metals, pesticides, microplastics and much more, that makes up wastewater and sewage. Recently, the Stockholm Resilience Centre, an international consortium of scientists, declared that the planetary boundary for “novel entities” — chemical contaminants introduced by humanity — has been transgressed, putting Earth’s operating systems and human civilization at risk. Cocaine excreted via urine, along with the toxic precursors used in its production, are among the many tens of thousands of novel entities of emerging concern.

A 2020 study led by Pavel Horký at the Czech University of Life Sciences grabbed headlines. His research showed that exposure to methamphetamine — another illicit drug identified in wastewater samples — altered behavior patterns and elicited signs of addiction in brown trout (Salmo trutta). To date, no one knows how drug mixtures, such as meth and cocaine, might combine with other pollutants to impact aquatic species.

“I totally agree with the Stockholm Resilience Centre that chemical pollution is one of the greatest threats for life in general, [as we pass] the novel entities boundary,” says Horký. “There are a lot of contaminants of emerging concern, not only illicit drugs, but also standard prescription medicines like antidepressants and many others that are overused by human society. Their risks may vary along with their additive, synergistic or antagonistic effects.

“Cocaine toothache drops,” an 1885 advertisement of cocaine for dental pain in children. The U.S. love affair with coke began in the 1800s, when it was commonly used in many “medicines” of dubious quality and efficacy and sold without prescription or regulation. While today mostly illegal for cultivation, transport and sale around the globe, some countries do allow cocaine possession for prescribed medical use, or have decriminalized possession of small amounts for private use. Image by KiloByte via Wikimedia Commons (Public domain).

“Despite the fact that our knowledge is increasing, we are still at the beginning,” he warns.

There are ways of guarding against this form of environmental harm. Removing cocaine residues from wastewater is possible, though treatment facilities vary in effectiveness. Other nature-based solutions, such as constructed wetlands, offer cleanup alternatives.

In Horký’s mind, there is an easier and cheaper solution: “The best pollutant is the one that is not released in the environment,” he states. “Everybody should think about it and use medicines, drugs and other chemicals responsibly [and for] real need.”

Mongabay