Long a concern elsewhere, everyday chemicals such as caffeine, nicotine, medicines or UV filters have now been detected in the waters of parts of Antarctica where there is no human activity
Human activities such as research and tourism in Antarctica are leaving behind a chemical footprint in the continent’s coastal and inland waters, scientists have determined for the first time.
The Spanish team that conducted the research on Livingston and Deception islands identified antibiotics, antidepressants, stimulants, UV filters from cosmetics and an anticorrosive in the freshwater of the two islands as well as in the surrounding coastal waters.
The research team collected the samples at various locations on and off Island, including at research stations, research camps and popular tourist spots. Samples were also collected in areas where there is no human activity, but, here too, traces of chemicals were found, implying that pollution can be moved around by ice, the air or other forces of nature.
The substances of greatest concern identified in the study are citalopram (an antidepressant), clarithromycin (an antibiotic), nicotine, (a stimulant that is also a lethal neurotoxin), venlafaxine (another antidepressant) and hydrochlorothiazide (a diuretic), according to Cristina Postigo, an environmental chemist at the University of Granada and lead author of the research team’s paper, published in the Journal of Hazardous Materials.
All these substances are categorised as contaminants of emerging concern, or CECs. Unlike persistent organic pollutants, the presence of CECs dates back only to the 1990s. Some of these chemicals are extremely persistent in the environment and highly toxic to animals and plants
The preliminary assessment of the risk to organisms indicates that the amount of concentrations pose just a low or moderate risk. However, the authors only searched for twelve pollutants, while pollutants known to be present in aquatic habitats in Antarctica were not considered. Furthermore, the study points out that the risk-assessment model used only analysed the pollutants individually and neglected possible interactions when several chemicals occur simultaneously.
Dr Postigo recommends, therefore, that monitoring in Antarctic waters and in the continent’s plants and animals continue.
Tolyltriazole, a corrosion inhibitor, was the most frequently identified chemical, appearing in 84% of the 38 samples. Nicotine, the second most frequently identified chemical, and citalopram had not been studied before in Antarctica, but, according to Miren López de Alda, a co-author of the study who holds a PhD in pharmacy, the research found the two chemicals in 74% and 55% of the samples.
Venlafaxine, hydrochlorothiazide and clarithromycin and caffeine (a stimulant) were also found in high quantities, appearing in up to half of the samples.
The only painkiller the research team found was diclofenac, and in only 3% of the samples; ibuprofen, acetaminophen and other common painkillers were not detectable.
Benzophenone (a UV filter) was detected in about a quarter of the samples.
Concentrations of the various contaminants were higher in freshwater, with a maximum of 292 nanograms per litre (citalopram), than in coastal waters, where benzophenone, with a concentration of 92 nanograms per litre, was the most prominent. A previous study of seawater found comparable concentrations of similar pollutants.
Julia Hager, PolarJournal
Postigo, C., Moreno-Merino, L., López-García, E., López-Martínez, J., López de Alda, M.; “Human footprint on the water quality from the northern Antarctic Peninsula region.”; Journal of Hazardous Materials. Volume 453, 2023.
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