Plastics are basically synthetic organic polymers of high molecular mass mainly derived from hydrocarbons obtained from crude oil and natural gas. Plastics are commonly produced from fossil fuels but nowadays biomass is increasingly used. Rapid urbanization and industrialization and overpopulation are making the conditions worse. Plastic waste is considered as one of the most persistent major waste in environment. Plastics have deleterious effect on the environment by destroying habitat, entangling marine animals, facilitating the transport of invasive species across habitats and depositing in sediments, leading to potential impacts on animals that live and forage in benthos.[1] According to the report from central pollution control board (CPCB) in 2017-18, India generated 9.4 million tons plastic waste annually. The 50% of plastic waste generated consists of single use plastic like straws, plates, food packaging etc. The recycle rate is only 10% for single use plastic and majority ends up in ocean affecting aquatic life and creating pollution. Management of plastic waste has become huge task for government resulting in banning of single use plastics in many states of India. Plastics cannot be decomposed and slowly breaks down into microplastics and remain in environment for thousands of years. A single plastic bottle cans stay in environment for thousands of year. The plastic waste management rules, 2016 specifies minimum thickness of 50 micron for plastic use in order to easily reuse and recycle the product.
Solutions
The basic techniques to stop this kind of pollution is landfill dumping, incineration, 3 R’s and resource recovery. However, the new and better techniques for this problem are:-
NON-USAGE AND REDUCTION IN USAGE OF PLASTIC: There are worldwide efforts to either stop or prevent the usage of plastic. The toy company, LEGO has announced its plans to begin making its famous plastic bricks from sustainable polyethylene, rather than from petroleum based sources. In India, The Ministry of Drinking Water and Sanitation has encouraged government offices to make alternative arrangements for providing drinking water that do not generate plastic waste. In addition to this, the states of Sikkim and Bihar have restricted the use of plastic bottles and Styrofoam drinking cups at government meetings.
PLASTIC RECYCLING: Recycling saves other resources and is good for our environment. A ton of recycled paper can save 25-30, 25000 liters of water and 4000 kWh of energy. The rate of plastic recycling is increasing every year but it is still estimated that roughly each year half of the global production of solid plastic is thrown away. Chemical methods of recycling includes processes such as catalytic pyrolysis which uses the plastic as a feedstock for the production of gases, waxes or fuels but it is not that successful due to the high energy consumption involved[2]. Another method which is currently used is depolymerisation. Efforts are also being made to find ways to process directly waste that contains mixtures of plastics, in order to avoid the laborious sorting of individual types of plastic from municipal waste. This is extremely challenging, due to the immiscibility of different kinds of plastic, and that only a small quantity of one type present in another can profoundly alter its properties, often making it unsuitable for a particular purpose.
DELIBERATE DEGRADATION OF PLASTIC: Some scientists have started research on to reduce the volume of the resulting plastic waste and to mitigate the resulting environment contamination. This method is similar to incineration but more advantageous than it as incineration produces a huge quantity of greenhouse gases upon combustion which contaminates the ecosystem. For example, a bacterium named Ideonella sakainesis 201-F6 was recently discovered which shows the remarkable property to use PETas a major carbon and energy source for it’s growth, as it secretes an enzyme (PETase) that can degrade PET. In a sense, this technique can be used to destroy plastic and keep it out of the ecosystem. There is another advantage too, as the decomposition products might be reused (recycled) back into new polymers or used for making other products, therefore conserving the fossil fuels too [3].
OXO-BIODEGRADABLE PLASTICS: Oxo-biodegradable plastics are neither a bioplastic nor a biodegradable plastic, but rather a conventional plastic mixed with an additive in order to imitate biodegradation. They are made from traditional plastics by incorporating oxidation catalysts into them, usually transition metals like Cobalt (Co) and Manganese (Mn) which cause the plastic to fragment as a result of oxidation of the polymer chains. The resulting fragments are intended to undergo subsequent biodegradation. Although, they are consider as substitute but they are equally dangerous as conventional plastics as these materials do not fully biodegrade, but rather disintegrate into microplastic fragments, and are therefore harmful to the environment similarly to petroleum-based [4].
BIOPLASTICS: Bioplastics are the plastic which are manufactured from renewable biomass source, for example vegetable fats and oils, corn starch, sawdust, recycled food waste, etc. they can also be prepared from agricultural by-products or from used plastics by using microorganisms. They are usually derived from sugar derivatives and lactic acid. Bioplastics are used for disposable items, such as packaging, crockery, cutlery, pots, bowls, and straws.[5] Since they are biodegradable they can be used as a substitute for the plastics which are generated from petrochemical substances.
Conclusion
Plastic is omnipotent and still we are consuming it at a rapid rate which is only worsening our condition. Plastic is not dangerous but it’s mishandling and overuse is the problem we are facing today. In the past few years, plastic waste has emerged as a powerful ally to global warming and acid rain which is making the climate degradation worse. Now it is time, we open our blinds and start fighting against these threats. We should create awareness amongst the masses and strictly follow the guidelines issued by the government to stop this threat.
References
[1]- Schmaltz E., Melvin, E.C., Diana, Z., Gunady, E.F., Rittschof, D., Somarelli J.A., Dunphy-Daly, M.M.(2020) Plastic pollution solutions: emerging technologies to prevent and collect marine plastic pollution.
[2]- Aguado, R., Olazar, M., San José, M.J. and Bilbao, J. (2002) Energy Fuels, 16, 1429
[3]- Yoshida, S., Hiraga, K., Takehana, T., et al. (2016) Science, 351, 1196–1199.
[4]-Plastic Pollution and Potential Solutions by Rhodes C.J.(2018).
[5]- Chen, G.; Patel, M. (2012). "Plastics derived from biological sources: Present and future: P technical and environmental review"
By Ujjwal Kumar Tripathi
ujjwaltripathi2012@gmail.com
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