By: Pablo Corso
The level of pesticides in fish, such as herbicides, is a global problem. The muscle tissue of edible tarpon (Prochilodus lineatus) from the Argentine province of Santa Fe is contaminated with “polar herbicide levels [solubles en agua] tallest in the world“says an article that will soon appear in the journal Science of the Total Environment.
Fish from the Salado River, a tributary of the Paraná (the longest South American river after the Amazon), showed traces of nine insecticides, herbicides and fungicides applied to transgenic soybean, corn and cotton crops that abound in this river basin.
Although the effects on fish and humans are not yet fully determined, the authors warn of the need for extreme precautionary measures in one of the most important waterways in the country, which provides food both locally and for export. “There is an urgent need to increase the distance between pesticide-dependent GMO crops and aquatic ecosystems, as well as to improve the approach to environmental risks.”. Rafael Lajmanovich, research team leader, told SciDev.Net that this distance should be at least 1,000 meters.
The researchers analyzed the river sediments, muscles and viscera of 16 tarpon purchased from fishermen along 100 kilometers of high agricultural productivity.
In muscle tissue have been foundvery high concentrations» the insecticide cypermethrin (up to 204 micrograms per kilogram); the fungicide pyraclostrobin (50 μg/kg); herbicides glyphosate (187 μg/kg), as well as its degradative acid AMPA (3116 μg/kg), and glufosinate ammonium (677 μg/kg).
Prior to this work, the highest levels of glyphosate recorded in fish were “below 10 ug/k” and “there was notinformation about the presence of glufosinate, Lajmanovich said in an email.
Urgent distance between spraying and aquatic ecosystems
“There is an urgent need to increase the distance between genetically modified crops dependent on pesticides and aquatic ecosystems, as well as to improve the approach to environmental risks”.
Posted in: “Cocktails of pesticide residues in Prochilodus lineatus fish from the Salado River (South America): first record of high concentrations of polar herbicides”.
A study on the effects of polar herbicides published in 2021 detected peak levels of AMPA of 300 ug/k in muscle tissue and 650 ug/k in the liver of fish Hoplosternum littorale (better known as cascarudos) of the same province, he said. another e-mail Andrea Rossi, one of the authors. Although there was no evidence of cellular damage or neurotoxic effects, alterations were found in the hematological parameters of the samples taken.
Acute exposure to the quantities found on this occasion, however, could generate “multiple” effects, both in fish and in humans, which would include genotoxicity (ability to cause genetic damage) and hormonal disruption, associated with appearance of tumors, malformations, dysfunctions of the reproductive system, neurotoxicity or immunological problems, explains Lajmanovich.
Between 2019 and 2022, the same researcher ―full professor in the Department of Ecotoxicology at the Universidad Nacional del Litoral― issued similar warnings about the combined effects of glyphosate with arsenic and microplastics.
The authors acknowledge that the high solubility of pesticides makes determining contaminant levels “problematic”, although this same solubility leads to an increase in their toxicity in aquatic environments, where fish membranes facilitate uptake.
High levels of hydrocarbons in tarpon
In this sense, the doctor of natural sciences Eric Speranza – who 14 years ago found high levels of hydrocarbons in tarpon blubber near the city of Buenos Aires – rejoices by telephone that it has been possible to measure glyphosate and glufosinate in fish. muscle tissue.
“This highlights the impact of soybean agricultural activitywarns the researcher from the Laboratory of Environmental Chemistry and Biogeochemistry of the Argentinian Universities of La Plata and Arturo Jauretche.
Yes OK “the presence of the herbicide does not necessarily mean that the fish are affected”, also suggests the advisability of avoiding its consumption until new studies determine with more precision the effects of pesticides on fish, although he specifies that it is, for the moment, a question of a decision of each consumer.
Regarding a possible provincial ban on fishing, Speranza is cautious, because it is a measure that “requires taking into account economic and social factors, such as the people themselves who live from this activity”.
Sources from the National Agrifood Health and Quality Service – responsible for controlling the safety of foods of animal and plant origin in Argentina – told SciDev.Net that the report “relative importance was givenbecause they have objections to their methodology, for example, in relation to the number of specimens analyzed.
Herbicide residues in tarpon and other fish
The agency does not currently measure pesticide levels in fish; maximum residue limits (MRLs) are established only for vegetables. Even so, they suggest that the values found do not pose a risk to human health. In the case of consumer soybeans, for example, the MRL for glyphosate is 5000 μg/kg.
However, the authors of the article insist that “Pesticide contamination of the Río Salado poses a detrimental threat to the viability of fish populations and other aquatic organisms, and a great risk to consumers.
Clear regulations on agrochemicals should establish tolerable maximums for these substances, they suggest, as this would allow a better approach to the situation.
Various attempts by SciDev.Net to obtain an official statement on the Santa Fe government’s future actions have failed until this reporting is closed.
> Link to the abstract of the article in Science of the Total Environment
This article was produced by the Latin America and Caribbean edition of SciDev.Net BioSource: https://www.scidev.net/america-latina/news/pez-argentino-con-niveles-de-herbicidas-mas-altos -del -mundo/?utm_source=SciDev.Net&utm_medium=email&utm_campaign=13825406_2023-03-13%20Weekly%20Email%20Digest%20-%20America%20Latina%20y%20el%20Caribe%20Template.%20For%20no%20topic%20_preferences8, ,B0L58T,XS7QJ,1