In Brazil, a group of researchers analyzed thirteen whitetip sharks (Rhizoprionodon lalandii) and all tested positive for cocaine and benzoylecgonine, the main molecule present in the drug. It looks like the beginning of a comedy film, but in reality there is very little to laugh about scientific study published in Science of The Total Environment, which also analyzed the fact that cocaine levels were three times higher in muscle than in liver, and that female sharks had higher concentrations of cocaine than males. The amounts of cocaine and benzoylecgonine found in the sharks “exceeded levels reported in the literature for fish and other aquatic organisms by up to two orders of magnitude,” the biologists said.
Harmful effect on sharks
The whitetip shark was chosen precisely because it lives along the coast of Brazil and is therefore more easily exposed to substances that people pour into the sea; a feature that makes him an “environmental guardian”. It is not yet known how cocaine may affect the health of the species, which the IUCN classifies as “vulnerable to the risk of extinction”, mainly due to overfishing. However, studies on the effects of coca on other fish are not reassuring, pointing to hormonal problems of various kinds. According to other research conducted on fish eyes, the drug can affect the animals’ vision and hunting ability. “It’s possible that sharks don’t metabolize cocaine as quickly as humans, and that the prolonged presence of the drug could disrupt their endocrine system and thus their hormonal regulation,” says Daniel D. Snow, professor and director of the Nebraska Water Center Laboratory, which researched the presence of steroids in rivers.
How did cocaine get to us at sea?
Scientists believe that cocaine enters the fish in two ways: through waste from the bodies of drug users entering the sewer system, and by clandestine cocaine-refining laboratories that dispose of pure cocaine down the drain. Sharks can ingest cocaine directly through their gills or eat smaller prey that contain the substance. According to the study authors, this bioaccumulation through the food chain may explain why sharks had higher levels of cocaine than other marine organisms analyzed in previous research.
The risk of damage to human health must also be considered. Unfortunately, the sharks studied are a relatively common food in Brazil, especially in the state of Rio de Janeiro: the cocaine they ingest could therefore also be indirectly ingested by those who consume shark meat.
Effects of human drugs on other animals
Researchers studies they also discovered traces of cocaine and other illegal drugs near major cities such as London and off the coast of Florida, with the risk that marine wildlife could have come into contact with them.
In contrast to what happens in mammals, where cocaine acts mainly in the brain, in fish the substance accumulates mainly in the eyes. He found this studies performed on zebrafish larvae (Danio rerio), small freshwater fish that are often used in toxicology tests. Schirmer and his team found other major differences between their tests and the results observed in mammals: while in mammals cocaine has a stimulant effect and causes hyperactivity, in zebrafish it suppresses the locomotor activity of these chemicals in the ecosystem,” concludes Schirmer, “we need a more detailed understanding of the processes of water absorption , because they are very different from the processes that occur by inhalation or injection”
One of the most sensational cases of cocaine ingestion by a wild animal is the case of the “cocaine-addicted bear”, as it was nicknamed. It’s about a black bear found dead of an overdose in a Georgia forest in 1985. The incident has inspired a horror comedy, but in reality it’s again an animal that died suffering the guilt of humans. The bear was found dead surrounded by what was left of a bag that investigators later believed belonged to Thornton, a notorious drug dealer. The medical examiner concluded that the 100 kg bear died of severe cocaine intoxication after ingesting approximately 3-4 grams of the substance. “An amount that would kill anyone,” the investigator stated.
In March 2023, an African servalunlawfully detained in the US, was admitted for medical treatment from an animal shelter, where a drug test was conducted that came back positive for cocaine. In 2022, the shelter again welcomed a capuchin monkey in the US, who was in possession of methamphetamine.
These stories are not comic stories, but rather emblematic examples of how human-produced toxic substances endanger animals “In many cases, the use of drugs by animals is caused by curiosity or simple hunger, but by the fact that they have themselves. access to these substances is often the result of human carelessness, if not cruelty,” according to National Geographic.
Drugs and the environment
Drugs harm not only people or animals who accidentally come into contact with them and take them, but also the environment World Drug Report 2022, a report by the United Nations Office on Drugs and Crime, published by the United Nations. (UNODC), with a section exclusively devoted to the link between drugs and the environment. The findings highlighted that illicit drug cultivation generally requires locations in remote, sparsely populated areas, far from any government presence. These areas can be home to very diverse and fragile ecosystems, such as those found in forest reserves and natural parks. According to the study Illegal coca cultivation could directly cause 30 to 60% of all deforestation in South America, which also results in a significant additional carbon footprint, the carbon dioxide released into the atmosphere by cutting down trees that no longer absorb carbon. The UNODC report also highlights the laundering of profits in agriculture, livestock and mining activities, which is usually accompanied by investment in irregular roads and clandestine airstrips, all of which threaten the integrity of forests and biodiversity. In fact, there are more than 25,000 private airstrips in the Brazilian Amazon alone, more than half of which are considered illegal and more than a quarter of which are located on protected or indigenous lands.
Similarly, the production of synthetic drugs requires the discharge of drug-related waste into forests and rivers or directly into sewers
In Europe, too, drugs have an impact on the environment: according to Belgian and Dutch authorities, drug-related toxic waste accounts for 10-20% of the total amount of waste found. In the Netherlands there have been many cases where manure has been dumped into pits, the fertilizer then used on the fields. However, higher acid concentrations can alter the health of soil and water bodies such as rivers and lakes, which can negatively affect aquatic ecosystems and cause damage to forests, crops and other vegetation.