Microplastic pollutants in Cauvery river, Indian

Problems

• Microplastic pollutants in Cauvery river.

  The Kaveri is one of the major Indian rivers flowing through the states of Karnataka and Tamil Nadu. The Kaveri river rises at Talakaveri in the Brahmagiri range in the Western Ghats, Kodagu district of the state of Karnataka, at an elevation of 1,341 m above mean sea level and flows for about 800 km before its outfall into the Bay of Bengal. 
  
  The primary uses of the Kaveri is providing water for irrigation, water for household consumption and the generation of electricity. 
  
  The river is the source for an extensive irrigation system and for hydroelectric power.[9] The river has supported irrigated agriculture for centuries and served as the lifeblood of the ancient kingdoms and modern cities of southern India. 
  
  The Kaveri river delta is a thickly populated delta, one which is frequently affected by tropical cyclones formed in the Bay of Bengal. 
  
  The Kaveri basin has a variety of flora and fauna. 
  Microplastics, industrial and agricultural waste being dumped into the Cauvery are causing hypoxic conditions in the river’s waters, harming marine life. 
  Microplastics are small pieces of plastic, less than 5 mm (0.2 inches) in length, that occur in the environment as a consequence of plastic pollution.
  
  Microplastics are present in a variety of products, from cosmetics to synthetic clothing to plastic bags and bottles. Many of these products readily enter the environment in waste.
  They can be classified into two categories based on their origin-
  Primary microplastics: include microbeads found in personal care products, plastic pellets (or nurdles) used in industrial manufacturing, and plastic fibers used in synthetic textiles (e.g., nylon).
  Secondary microplastics: originate from the breakdown of larger plastics. Plastic bottles, bags, fishing nets, and food packaging are some examples of the larger pieces that break down into microplastics, eventually finding their way into the soil, water, and the air we breathe.
  
  Microplastics are found in several household and industrial products, and chemicals containing the cyclohexyl group, such as cyclohexyl isocyanate, are commonly used in agriculture and the pharmaceutical industry.
  
  Microplastics and other pollutants may be causing growth defects and skeletal deformities in fish inhabiting the Cauvery river, a study led by researchers from Indian Institute of Science (IISc), Bengaluru, has found.
  
  The researchers analysed water samples from the river for levels of pollutants, and studied their microplastic composition. They then studied embryos of zebrafish incubated in these samples in the lab and found them to have growth and skeletal deformities, reduced heart rate, reduced life span, and DNA damage.
  
  The damage was attributed to molecules called Reactive Oxygen Species (ROS), which are highly reactive chemicals derived from oxygen molecules, in the cells of the fish.
  In water, microplastics can enter fish and other organisms, and in turn, pass higher up the food chain, even ending up on human plates. In animals, they can cause a range of damage to cells and DNA, affecting ecosystems across the world. 

• Impacts of microplastic pollution

  ● On human health.
  Human exposure to microplastics is likely to come from airborne dust, drinking water (including treated tap water and bottled water)
  Microplastics can reach our stomach where they can either be excreted, get entrapped in the stomach and intestinal lining, or move freely in body fluids such as blood, thereby reaching various organs and tissues of the body.
  Negatively affects the nervous system, hormones, immune system and have cancer-inducing properties.
  
  ● On marine ecosystem.
  On marine organisms: when consumed, microplastics are stuck in their digestive tracts and also alter their feeding behavior.
  Accumulation of toxic plastics in the stomach leads to starvation and death, resulting in reduced growth and reproductive outputs.
  Magnify marine pollution: by acting as a binding and transporting agent for heavy metals and organic pollutants because of its water-repellent properties.