The ban on plastics that are used once and discarded is generally thought of as a good thing, but there is another side to it, points out a scientific paper published in Environmental Science & Policy.
Authored by three researchers of the Norwegian Institute of Water Research, Oslo, and two from Mu Gamma Consultants based in Gurugram, the paper notes that a corollary of the single-use plastic ban is the use of biodegradable alternatives, not all of which are fully biodegradable in all environments.
At the outset, the authors say they took up India’s ban for study, owing to the country’s size and complexity.
They note that, internationally, compostable plastics typically refer to any plastic that can degrade under composting conditions, often through hydrolysis, thermal degradation, and photodegradation. “However, this does not mean that compostable plastic products will break down completely (with no residues <2mm), degrade in all composting environments (like home compost), or that this process will be without undesirable impacts (microplastic particles and toxic additive releases),” the paper notes.
Moreover, it must be recognised that biodegradable plastic waste may be transported from an environment certified for biodegradability (for example, soil) to another environment where it is not (such as waterbodies). Thus, the potential rate of compostability and biodegradation in Indian soil contexts should be considered when looking at alternatives.
In the Indian context, studies have pointed out that kulhad (earthen) cups and virgin cotton bags having a higher environmental footprint than the single-use plastic they are replacing.
In June 2018, India announced its commitment to eliminate all single-use plastic by 2022 and called for a global phase-out by 2025. The government notified two amendments to the Plastic Waste Management Rules. Single-use plastic made from compostable plastics are exempt from the ban, but manufacturers must first register with the pollution control boards.
It is also proposed that any post-amendment notification prohibiting manufacture, sale and use of single-use plastic will face a 10-year delay to come into force. The authors warn of “severe long-term implications” from this.