Ocean pollution has been a serious concern since it affects the flora and fauna of the water bodies extensively. It has been calculated that about 4 to 12 million tonnes of plastic waste enter the oceans each year, mostly through rivers.
The visible plastic waste is covered extensively by media and movements have been conducted across the globe against irresponsible discard of plastic waste in water bodies. However, this visible plastic waste form only 1% of the total marine plastic budget. The other 99% of plastic constitute micro-plastics that often avoid detection, but are harmful nonetheless.
According to a study conducted by the University of Manchester, up to 1.9 million plastic pieces per square meter was found on the ocean floor in the form of microplastics. This is the highest level ever recorded on the seafloor. These plastic pieces included fibres from clothing and other synthetic textiles and tiny fragments from larger plastic objects that had broken down over time.
What are microplastics?
Microplastics are tiny plastic particles that result from both commercial product development and the breakdown of larger plastics. Officially, they are defined as plastics less than five millimetres in diameter
There are two categories of microplastics – Primary and Secondary
Primary microplastics are tiny particles designed for commercial use. For example, microplastics are found in cosmetics including scrubs, mascara, shampoos, etc. Additionally, they are in the form of microfibers shed from clothing and other textiles, such as fishing nets. Secondary microplastics are particles that result from the breakdown of larger plastic items, such as water bottles. This breakdown is caused by exposure to environmental factors, mainly the sun’s radiation and ocean waves.
How are microplastics harmful to Marine life?
Marine animals at the base of food-chain such as phytoplanktons are known to consume microplastics, thus entering into marine food-chain and subsequently, human food. These plastics may contain toxic chemicals like phthalates, Bisphenol A (BPA) and others used in the manufacturing process. These chemicals are injurious to marine life and damaging to ocean ecology.
Microplastics in the human ecosystem
According to industry estimates, an average Indian consumes approximately 11 kg of plastic products in various forms every year
Scientists say that plastic particles can reach our stomach, and depending on their size, these plastics are either 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.
The Guardian reports that a study carried out by Austrian scientists had shown that stool from individuals in eight surveyed countries contained microplastics. Similarly, high levels of BPA (Bisphenol A), a chemical used for making several plastics have been found in the urine of teenagers, in another study done by scientists from the University of Exeter based at the United Kingdom.
How do microplastics affect humans?
A number of studies have shown negative effects of plastics on the nervous system, hormones, immune system and the cancer-inducing property of plastics are already well-known. Scientists are now trying to understand how the basic machinery of the body interacts with plastic particles.
In a new study, Chandrasekaran, Professor at Vellore Institute of Technology in Tamil Nadu—who is engaged in studying the impact of microplastics in humans—and his colleagues have looked at the interaction of nanoplastics with blood proteins and cells. Nanoplastics aggregate in the blood, obstructing its flow in the body and render blood proteins non-functional.
It was found that blood proteins such as albumins, globulins, fibrinogens, which play an important role in osmotic pressure, molecular transport, blood coagulation, immune response etc., are absorbed on the surface of nanoplastics forming a plastic-protein complex with size ranging from 13 to 600 nanometers. Once plastic particles are fully surrounded by proteins, the plastic-protein complexes are attracted towards each other resulting in aggregation of these complexes.
Scientists say that these aggregates in the bloodstream can block the flow of body fluids. The aggregated plastic-protein complex is more toxic and potent in causing the death of white and red blood cells than the nano-plastic alone.
Dealing with Microplastics
Dealing with these evil polluters is imperative for human health as well as for thriving ocean ecology. There is no sure shot way to destroy the existing microplastics from the oceans. Which is why it makes sense to avoid products that release them in the first place.
Many countries have legislation in place that would ban the products that release microplastics in the near future. This would compel the companies located within their borders to find alternatives for manufacturing products without microplastics. However, this will only solve a fragment of the problem. It is only when these products will go out of use globally, which would be possible if the demand for these products drops. Citizens of the world need to shoulder the responsibility for ensuring this.