Researchers from the University of the Basque Country have detected and measured the presence of the antidepressant amitriptyline, the antibiotic ciprofloxacin and the sunscreen oxybenzone in fish. These pollutants produce secondary effects in the plasma, brain and liver of these animals.
There are more and more residues of drugs and personal care products in aquatic ecosystems, and concern is growing, both in the scientific community and in society, about the secondary effects that they can cause to aquatic living beings. Great efforts have been made to identify and control these types of pollutants and their by-products in sewage treatment plants and in environmental surface waters, but one of the great challenges remains to assess what effects they have on biota.
In this context, researchers from the Department of Analytical Chemistry of the University of the Basque Country (UPV / EHU) have developed analytical methods to measure the content of antidepressants, antibiotics and ultraviolet filters in water and fish. They have also analyzed the accumulation of these pollutants in fish tissues and fluids, their transformation and the effects they have at the molecular level.
Until now, through environmental biomonitoring, the risk of accumulation of these substances in fish and other aquatic organisms had been proven, but the way in which drugs are accumulated, distributed, metabolized and eliminated has not been thoroughly investigated. personal care products in the tissues and biological secretions of these organisms.
"The lack of knowledge about the transformation and biodegradation of drugs and personal care products can lead to underestimate the true effects of exposing fish to these pollutants - explains UPV / EHU researcher Haizea Ziarrusta Intxaurtza–. These by-products (the derivatives of the transformations and the metabolites) can be as or more dangerous than their precursors ”.
In this sense, Ziarrusta and other authors, who publish their study in the journalEnvironmental Toxicology and Chemistry, have detected that the antidepressant amitriptyline, the antibiotic ciprofloxacin and the ultraviolet filter oxybenzone can accumulate in fish and that these pollutants “produce side effects in the plasma, brain and liver of these, because they interfere with their metabolism, and can even affect them at the organism level ”.
Searching for an answer, dozens of questions arise
The team first optimized different analytical methods "to be able to determine drugs and personal care products in the water and in the tissues of the fish," explains the researcher. Using these methods, the existence of these pollutants has been found in various Biscayan estuaries and in fish, but "we wanted to see the effects they have on fish, analyzing the changes that occur in their metabolism."
They have carried out exposure experiments with seabream at the Plentzia Marine Station, in which they have evaluated the bioaccumulation of amitriptyline, ciprofloxacin and oxybenzone and their distribution in the tissues of these animals.
“Furthermore, we have investigated the biotransformation of these pollutants and characterized their degradation products; Finally, we have investigated the changes caused by these pollutants at the molecular level, analyzing the metabolism of the fish ”, adds Ziarrusta.
Although the analysis of the contaminants has been carried out separately, the scientist clarifies: “First we must understand things separately, in order to later be able to understand what happens in general terms. In reality, there is not just one pollutant in the water, and the fish are constantly exposed ”.
The researcher indicates that there is a lot of work to be done: “The concentration of these types of pollutants is worrying, because consumption is increasing and in treatment plants we are not able to eliminate them, they reach the fish and are changing their metabolism. We do not know to what extent that will influence at the individual level, and the problem could reach population levels. As we pollute the sea, that is, as pollutants increase, the situation worsens, and it is necessary to know if there is a risk that the pollutants accumulated by fish reach humans ”.
According to Ziarrusta, “the analytical approaches that we have developed can also be used to investigate other types of pollutants and species; in this way, decisive information can be gathered to evaluate environmental risks and establish new regulatory measures ”.
Haizea Ziarrusta, Anton Ribbenstedt, Leire Mijangos, Sergio Picart-Armada, Alex Perera-Lluna, Ailette Prieto, Urtzi Izagirre, Jonathan P. Benskin, Maitane Olivares, Olatz Zuloaga, Nestor Etxebarria. "Amitriptyline at an environmentally relevant concentration alters the profile of metabolites beyond monoamines in gilt-head bream."Environmental Toxicology and Chemistry,2019. DOI: 10.1002 / etc.4381.
This research is part of the doctoral thesis carried out by Haizea Ziarrusta Intxaurtza (Dima, 1990), in the Department of Analytical Chemistry of the Faculty of Science and Technology and in the Plentzia Marine Station of the UPV / EHU, under the direction of the Professors Maitane Olivares Zabalandikoetxea and Olatz Zuloaga Zubieta. He has completed a stay at the University of Stockholm (Sweden), to implement metabolomics extraction and analysis methods, and another at the Polytechnic University of Catalonia, in Barcelona, to learn data processing methods. In the research they have had the collaboration of experts in Organic Chemistry and Biology.