Plastic Bags: A Science-Based Sustainable Choice for Singapore

Recent research by Nanyang Technological University (NTU) has revealed an unexpected but important insight: plastic bags can be more eco-friendly than paper and cotton bags in densely populated countries like Singapore.

The study, published in the Journal of Cleaner Production, evaluated five types of shopping bags based on their full life-cycle environmental impact, including production, transportation, distribution, waste collection, treatment, and end-of-life disposal.

According to Assistant Professor Grzegorz Lisak, Director of the Residues and Resource Reclamation Centre at the Nanyang Environment and Water Research Institute, sustainability must be evaluated case by case.

“In a well-structured, closed metropolitan waste management system with incineration treatment, using plastic bags may be the best option currently available, provided there is no significant leakage of waste into the environment.”

In Singapore, where most non-recyclable waste is incinerated, the biodegradation timeline of paper, cotton, and other biodegradable materials becomes largely irrelevant. What matters most is the overall environmental footprint created during production and disposal.

The research concludes that:

• Reusable plastic bags are the most environmentally friendly option

• Single-use HDPE plastic bags are the next best choice

• Switching to paper or cotton bags can increase environmental impacts such as global warming potential and eco-toxicity

These findings highlight the importance of making informed, science-based decisions, rather than relying on assumptions about sustainability.