Recent research claims microplastics are causing growth abnormalities in fish in the Cauvery River, including skeletal malformations. The study was led by Upendra Nongthomba, a professor at the Indian Institute of Science‘s Molecular Reproduction, Development, and Genetics (MRDG) department. The study was published in the Ecotoxicology and Environmental Safety Journal.
Nongthomba, passionate about freshwater fish, became aware of their deformities and researched this aquatic species. According to a news release, the backwaters of the Krishna Raja Sagara [KRS] Dam, as well as eating fried fish on the Cauvery Riverbank, have become essential spots for him throughout the years. Nonetheless, he later observed physical flaws in some of them and began to wonder if the water’s quality had a role.
Many living things, like animals and plants, need water to stay alive. Cancer and other diseases can happen if it gets infected with it, says PhD student Abbass Toba Anifowoshe. He is also the Study’s first author and the person who started the project.
In the lab of Prof. Nongthomba, a very detailed study of pollution at the KRS dam and its possible effects on fish was done there, too. They took water samples from three different places with different water flow speeds because it is known that the rate of water flow affects the number of contaminants in water samples.
As part of the initial phase of their research, the team examined the physical and chemical characteristics of the water samples that they were considering—all of them, except one, comply with the guidelines. The only exception was dissolved oxygen, which was found in low concentrations in samples obtained from slow-moving and motionless areas of the river. These waters also included bacteria such as cyclops, daphnia, spirogyra, a spirochaete, and E. coli, well-known bioindicators of contaminated water, such as those found in sewage.
The researchers conducted more research. They identified microplastics, which are microscopic plastic particles that are typically invisible to the naked eye, as well as some hazardous substances, using a technique called Raman spectroscopy.
The second portion of the study, which was undertaken by the same team, examined the impact of pollutants in water on fish. It was demonstrated that when zebrafish embryos were exposed to slow-flowing and stagnant water samples from the three sites, they had skeletal abnormalities, DNA damage, early cell death, heart damage, and more significant mortality. These faults remained obvious after the microbes were removed from the sample, demonstrating that microplastics and hazardous chemicals were still exacerbating the problem independently.
The findings are significant in light of recent Dutch research demonstrating that microplastics may reach the circulation of people. The researchers observed that the levels of contaminants detected in the fish may not be worrying for humans just yet. Nonetheless, long-term consequences cannot be ruled out.
Scientists added, however, that they did not completely understand how microplastics enter and influence the host and hence could not answer the issue decisively. “This is an issue that we are attempting to solve today,” the scientists were quoted as stating in a news statement.
Furthermore
The researchers detected unstable molecules known as ROS (Reactive Oxygen Species) in the cells of the fish that were not growing normally. In addition to causing DNA damage, ROS buildup has been shown to influence animals in ways that are similar to those reported by Abass and Nongthomba in fish treated with water from slow-flowing and close locations.
According to other research findings, microplastics and chemicals containing the cyclohexyl group have been shown to lower DO, which leads to the accumulation of ROS in animals such as fish.
According to a recent study conducted in the Netherlands, microplastics can enter the human circulatory system.
So, what do the findings of Nongthomba’s laboratory mean for the millions of people who rely on Cauvery water for their daily needs?
According to him, “Although the numbers we documented are not worrying for individuals at the time, long-term consequences cannot be completely ruled out.” However, he acknowledges that before they can provide a definitive response to the issue, they must first understand how microplastics penetrate and cause harm to the host. “This is a problem that we are currently striving to resolve.”
Edited By: Vanshika Sahu
Published By: Akshaj Joshi
