News

Imposex: the evil that masculinizes female snails with the appearance of pseudo penises

Sample taken in Neguanje, Tayrona Park.
Sample taken in Neguanje, Tayrona Park.

All boats have bottoms, the part of the ship’s hull that remains in the water and also receives the maximum load. This area is commonly distinguished because it is red or yellow in color and because, in order to prevent marine life from adhering to it and consequently lead to fuel savings and less friction when sailing, it has a layer of antifouling paint with an active compound of tributyl tin (TBT), a substance that today is putting the lives of some at risk snails from sea.

The reason for this has to do with the degree of toxicity of the substance, which, in addition to being abundant in port areas, causes serious mutations in female snails. In the research carried out by Dr. René Rodríguez, between 2015 and 2017, five species of snails that in one way or another were affected (Plicopurpura patula, Vasula deltoidea, Stramonita haemastoma, S. floridana and Gemophos auritulus), since the effect of the substance in animals blocks the formation of female hormones.

“Then, the animal practically has two reproductive organs, the female one, which is in the case of females, the one with which it grew up and later, in the presence of this chemical compound of tin, masculinizing traits appear, such as the formation of a pseudopenis and vas deferens. This, in adult females, prevents the eggs that are formed by blockage of the oviduct from being released and finally, as a consequence, the animal dies”, explains to Infobae Colombia Néstor Hernando Campos, a marine biologist and one of the tutors of the research.

In the image it is possible to notice how the female snails present the appearance of male sexual organs.
In the image it is possible to notice how the female snails present the appearance of male sexual organs.

This, Dr. Rodríguez explains for this medium, is a phenomenon known as imposex, that “it has an impact of local extinction of sensitive species”, since it is in the places with more marine traffic, particularly in the ports, where the population of these mollusks can be more affected and decrease.

It may interest you: The increase in ocean temperature was once again a record in the last year and puts ecosystems at risk

In this order of ideas, an impact of this magnitude not only prevents the reproduction of animals but also poses a critical scenario for the species, with Danger of extinction for areas affected by chronic TBT contamination.

To better verify this, Rodríguez collected and analyzed samples from two areas: Bahía de Santa Marta, with the sites of Punta de Betín and the Marina Internacional de Santa Marta, and the area of ​​the Tayrona National Natural Park, in Bahía Concha and Neguanje. . Also, to the northeast of Cabo de la Vela and to the west in Tierra Bomba in Cartagena, samples were collected and the levels of contamination by said substance were reviewed to study this phenomenon in individuals living in rocky areas and ports.

According to Dr. Rodríguez’s research, the sites with the highest incidence of maritime traffic turned out to be the most affected by the phenomenon of imposex. In this sense, of the affected and studied areas, although it is difficult to establish the contributions of the specific sources of contamination, the Tayrona National Park, despite being a reserve area, also presented more concentrated TBT indices in holiday seasons, fact that affects conservation goals.

This means, in the words of Rodríguez, that contamination is a slow process that is reflected more in places where the ships are docked. “There are scientific articles that justify the presence of affectations near shipping routes and in the research we carried out we found affectations even in the Tayrona Park. This area is protected, but there are tourist yachts and some boats that fish in an artisanal way from the shore”, he explains and warns that on many occasions these boats are painted in an artisanal way with antifouling products that may contain TBT.

It may interest you: Climate change and artificial intelligence among Bill Gates’ predictions for 2023

Previously, in order to prevent algae and molluscs from adhering to the hull of the boats, many boats used copper as an active antifouling compound. The technological appearance of TBT in antifouling paints was of great help to the shipping industry and maritime transport, but it generated damage to the environment.

However, after discovering the effects of TBT, in 2008 the International Maritime Organization (IMO) banned its use. At the time, the first countries to adopt new measures were those that belong to the European Union. So, despite the fact that today there are alternatives that replace these paints with others with less residual effect and that have not been proven to put life in aquatic ecosystems at risk, for Rodríguez, it is the artisan uses of these paints that may be causing this type of contamination which becomes evident in the study.

For this reason, in dialogue with Infobae, the expert is emphatic about the need to work “together with the maritime authority for the control of medium and small vessels”, because although at present the General Maritime and Port Directorate (DIMAR) requires all vessels in ports a certificate that guarantees that they are free of the polluting agent, there are indications that smaller vessels for tourist use or artisanal fishing may be using paints with the inclusion of TBT.

The study warns that the most affected population of individuals on the Colombian Caribbean coast are snails that are predatory organisms within the trophic structure, feeding on other individuals.

This suggests a problem that scientists highlight as important, because counting on the fact that each species fulfills a role within the trophic chain, presenting a panorama without the presence of these snailswho perform a work of population control about other species that are their source of food, suggests that in the future nature would be facing an ecological imbalance.

It may interest you: Young people from the departments of Bolívar and Sucre could be at risk of mercury poisoning: what the environmental authorities say

But that is not all. Starting from the fact that these animals constitute part of the diet of some coastal communities, the question also arises about the effects of TBT in humans.

“Look, this is tricky. The investigations that publish the effects of tributyltin in vertebrates are very few. As far as I have done my review, I have found that the effects of TBT in aquatic vertebrates occur at the level of the nervous system. However, today, there are no studies on TBT in humans and if there are, they have not been published”, says Rodríguez.

In this sense, the research not only opens spaces to give continuity to new studies but also raises an important need: to continue monitoring this situation through the collection and analysis of evidence to define how it evolves and continue working on the prohibition of the substances that endanger marine life.

In areas far from the cities, the vessels responsible for this contamination are those that remain at sea.  The traditional use of TBT is one of the reasons that sets off alarm bells today.  Photo taken in Bahía Concha.
In areas far from the cities, the vessels responsible for this contamination are those that remain at sea. The traditional use of TBT is one of the reasons that sets off alarm bells today. Photo taken in Bahía Concha.

Keep reading

Leave a Reply

Your email address will not be published. Required fields are marked *

Back to top button