Sazzadul Islam:

THE presence of plastics, from the Himalayas’ peak to Challenger Deep — the deepest known point of the seabed of Earth — highlights plastic pollution as one of the most severe environmental crises of our time. While challenges like greenhouse gas emissions remain uncontrollable, the escalating threat of plastic pollution demands immediate attention.

Plastics encompass a vast range of polymers, from natural to synthetic and semi-synthetic. The synthetic plastic industry, with a history spanning over a century, has grown exponentially due to plastic’s many advantageous properties, including its lightweight nature, durability, low cost, versatility, waterproof and insulating qualities, and ease of manufacturing. Statista reports that global plastic production reached 413.8 million tonnes in 2023, marking a sharp increase from only 1.5 million tonnes in 1950. This rapid growth is a reflection of plastic’s widespread use across almost all sectors, but it also contributes to the growing environmental disaster.

In Bangladesh, a World Bank report shows that per capita plastic consumption rose from 3 kg in 2005 to 9 kg in 2020. However, only 31 per cent of the 977,000 tonnes of plastic consumed in 2020 was recycled. The lion’s share of this plastic waste, therefore, likely ended up in the environment. In Dhaka, annual plastic consumption per capita is 22.25 kilograms — more than three times the national urban average.

Improperly managed plastic waste finds its way into the ecosystem, where it accumulates because our environment lacks microorganisms capable of breaking down these artificial polymers. It can persist for hundreds to thousands of years before it degrades, if at all. By that time, irreversible damage has often already been done. According to the Organisation for Economic Cooperation and Development, global plastic waste generation reached about 353 million tonnes in 2019. This figure is more than double the amount generated in 2000, and if trends continue, it could nearly triple by 2060.

Once plastics enter the environment, they undergo various physical, chemical, and, to some extent, biological processes that break them down into microplastics and nanoplastics. Microplastics typically range in size from 5 millimetres to 1 micrometre, while nanoplastics are smaller than 1 micrometre. These smaller particles, along with the toxic organic compounds released from plastics, alter the physico-chemical properties of soil. This impacts soil health, affecting porosity, capillarity, wetting-drying cycles, and evaporation, and harms plants, animals, and microorganisms that ingest or are affected by these toxic substances. This disruption leads to the malfunctioning of terrestrial ecosystems and a reduction in ecosystem services, vital processes that support life on earth.

In the marine environment, plastics break down into microplastics and nanoplastics primarily through the action of ultraviolet radiation and ocean currents. These particles have a devastating impact on marine life and disrupt the delicate balance of marine ecosystems. Studies suggest that plastic pollution in the oceans dates back to the mid-20th century, when the first traces of plastics were found in seabird stomachs. As small fish, a common food source for seabirds, ingest these particles, the extent of marine plastic pollution becomes clearer. Today, fragile coastal and marine ecosystems are under severe threat from plastic pollution, exacerbated by both native and foreign sources.

Now, nearly 11 million tonnes of plastic enter the world’s oceans annually. Once plastic enters the ocean, it is carried across vast distances by ocean currents and other natural mechanisms, spreading pollution widely. Countries that are least responsible for plastic production often bear the brunt of its consequences. These nations face environmental degradation, economic costs, and the loss of vital ecosystem services that they cannot easily mitigate.

Plastic pollution has now crossed the line into human health. For the first time in 2022, microplastics were detected in human blood, sparking widespread alarm. We are exposed to these particles primarily through food, water, and air. Toxicologists are raising concerns about the potential health impacts of plastic exposure, linking it to metabolic issues, hormonal imbalances, respiratory problems, cancer risk, digestive system damage, and more. Among these particles, nanoplastics are particularly dangerous due to their small size, which allows them to penetrate the bloodstream and their large surface area, which enables them to react more rapidly within the human biochemical system.

The issue of plastic pollution extends beyond environmental concerns. Plastic materials also leave a significant carbon footprint throughout their lifecycle—from raw material extraction to disposal. This contributes to another pressing environmental crisis: global warming. A scientific report by the Lawrence Berkeley National Laboratory, published in early 2024, reveals that the production of plastics in 2019 generated approximately 2.24 gigatonnes of carbon dioxide equivalent, accounting for 5.3 per cent of global greenhouse gas emissions, excluding agriculture, land use, and forestry.

Tackling the plastic problem is not an overnight task. The goal should be to replace plastics with affordable and sustainable alternatives while reducing, reusing, and recycling as interim measures. On a personal level, reducing plastic waste involves using fewer plastic products, reusing items when possible, and disposing of plastic waste in designated areas for proper management. These efforts can be implemented without large-scale workshops or initiatives, but instead through individual awareness and actions.

The government must create a structured, long-term framework that integrates scientific research and sustainability into policy and law. Bangladesh was the first country to legally ban polythene bags in 2002, but the law was poorly enforced, and there were no practical alternatives in the market. This led to its failure. Future measures must avoid these pitfalls by ensuring viable alternatives are available and implementing effective enforcement mechanisms. Additionally, voluntary organisations can play a crucial role in raising awareness about the harmful effects of plastics and encouraging individuals to adopt sustainable practices.

At the international level, there is an urgent need for coordinated action. The global community should implement a milestone agreement to immediately address plastic pollution and work towards neutralising its harmful effects. While bioplastics have been developed as alternatives, they are not yet a comprehensive solution due to concerns about their biodegradability, economic viability, and management. To make meaningful progress, further interdisciplinary research is necessary to identify truly sustainable alternatives to conventional plastics.

As Chief Seattle wisely said, ‘The Earth does not belong to us; we belong to the Earth.’ If we continue to damage our planet, every aspect of human life, from politics and economics to health and survival, will face unimaginable dangers. We must act now to protect the Earth and its ecosystems before plastic pollution renders our world uninhabitable for future generations.

Sazzadul Islam writes on the environment.