The Sustainable Bag Dilemma | Article by Professor Mercy Mpinganjira

As we evolve to a sustainable future, it becomes more and more important to integrate our daily life practices into an integrated version of them. Shopping bags depict a new and vital aspect there: From plastics to papers, sometimes cotton; we acquire a high variety of them. In culture and the media, it is often suggested that plastic bags are always the least sustainable and harmful to the environment. However, it is again important in this issue to investigate the options in a detailed fashion and get conscious.

We asked Professor Mercy Mpinganjira to share her expertise on this issue. As the Director of the School of Consumer Intelligence and Information Systems of the University of Johannesburg, Professor Mpinganjira previously researched this issue. “Factors Influencing the Use of Non-Plastic Reusable Shopping Bags: A Cognitive-Normative-Habitual Approach”, the research conducted by her, Asphat Muphoshi and Marius Wait tells a lot about this universe of options when it comes to shaping sustainable choices on shopping bags. Here, there is a seminal article prepared by Professor Mpinganjira for Luxiders Magazine to stream consciousness on this issue.

SUSTAINABLE CONSUMPTION AND THE BAG DILEMMA

Which type of bag do you use for your shopping? In a world characterized by rampant consumerism and environmental degradation, the decision to use plastic, paper and/or cotton shopping bags carries with it significant ecological weight. This is mainly because the production, use and disposal of shopping bags, irrespective of whether they are made of plastic, paper, cotton or other materials, has far reaching environmental impact. Debates however abound over the most sustainable bagging options. In delving into the realms of sustainable consumption and the shopping bag dilemma, this article sheds light on the environmental merits and drawbacks associated with the different options. We start off by highlighting one of the most common misconceptions associated with shopping bags and sustainable consumption.

MISCONCEPTION # 1 – PAPER AND COTTON SHOPPING BAGS ARE THE BEST IN SOLVING SUSTAINABILITY PROBLEMS

While paper and cotton bags are often seen as the greener alternatives, all types of bags have potentially very large negative impact on the environment. This is more so because the sustainability score of different options depends on many factors including resources used to extract the raw materials used in making the bags, the process undertaken to manufacture the bags, as well as the durability, reusability, recycling and biodegradability. Focusing only on one or a few factor such as reusability or biodegradability has led many to make choice decisions that are based on an incomplete picture and have a false sense of being active contributors to sustainability. For example, while based on biodegradability, paper bags are often preferred over plastic bags, their limited durability can lead to high demand for new bags. Considering that compared to plastic bags, paper bags are associated with higher carbon emissions, it is important for shoppers to focus not only on the type of bag being used but also the quantity used if they are to meaningfully contribute to sustainable consumption.

In order to effectively address the shopping bag and sustainability dilemma shoppers need to understand and consider the life cycle approach to choosing shopping bags. The life cycle approach entails considering the full life cycle of a bag from material sourcing and production, distribution, use and end-of-life (post-use) stages.

MATERIAL SOURCING AND PRODUCTION

This is the stage associated with the extraction of raw materials and the actual process of manufacturing shopping bags. Issues that every shopper concerned with sustainability needs to consider at this stage include use of renewable vs non-renewable resources, levels of water and energy consumption, emissions and waste generation during the sourcing and production stage.

Plastic bags are typically made from petroleum-derived polymers. The processes involved in the extraction and refining of fossil fuels used in plastic production thus lead to the depletion of non-renewable resources and are known to contribute substantially to carbon emissions.

Manufacturing of paper bags on the other hand requires logging of trees and processing of wood into pulp. The process entails heavy use of water and chemicals apart from energy. In countries struggling with good forestry management practices, the production of paper bags may not be the best option.

Cotton bags are made from natural fibre, obtained from cotton plants. Commercial production of cotton is widely associated with the use of large amounts of fertilizers, pesticides and water. As a result, if sustainable farming practices such as organic farming or regenerative cultivation practices are not promoted, shoppers should be wary of using cotton bags due to their likely contribution to pollution and soil degradation.

When choosing any shopping bag, wise shoppers will go beyond the simple question of whether it is made of plastic, paper, or cotton and look for evidence of sustainability practices in the production process.

DISTRIBUTION

Once the shopping bags have been manufactured they need to be transported and delivered to distribution centers, wholesalers, and retailers before they can get to the final shopper. Key considerations that shoppers need to keep note dealing with the sustainability dilemma include distance traveled and packaging efficiency. If shopping bags are being imported from other countries or transported within a country over a long distance to the final destination, the impact of high energy consumption and associated emissions will have a negative impact on the sustainability score in general. When comparing plastic, paper, and cotton shopping bags based on sustainability during the distribution stage customers it needs to be borne in mind that plastic shopping bags are in general lightweight and compact making them more efficient to transport as they require less space. Paper and cotton shopping bags on the other hand tend to be bulkier and heavier thereby requiring more space to transport the same number of bags.

THE USAGE STAGE (2)

The usage stage of the shopping bag life cycle refers to the period when the bag is in active use by shoppers. In assessing different bags based on sustainability, key shopper considerations are to include durability and reusability. Durability is about ability to withstand wear and tear and function effectively over a longer period of time. Plastic and paper bags unlike cotton bags are prone to tearing and are thus less durable than cotton bags. Use of cotton shopping bags reduces the need for frequent replacement and is thus helpful in reducing waste generation.

Reusability is more about ability to use a bag multiple times for varied purposes. Just as with durability, the ability to re-use bags is helpful for conversing resources and reducing waste production.

DISPOSAL STAGE

Shoppers, in managing the shopping bag dilemma, consider the sustainability score of different bags after their useful period. When a shopping bag has reached disposal stage, there are three main possible destinations including recycle, incineration and landfill in order of priority. Recycle entails the conversion of in this case the old bag into new products. The ability of the shopping bag material to be recycled and converted into other useful products is  key consideration under this factor. Plastic, paper and cotton differ in terms of recyclability. Paper bags are generally more easily recycled than plastic bags. While cotton bags can be recycled, they are not commonly disposed of in this way. Their durability and high levels of potential re-use make them a sustainable choice that reduces the need for recycling.

Incineration entails burning bags at high temperatures. This method of disposable is generally not considered to be among the best ways of disposing shopping bags due to the fact that it exacerbates environmental degration through emission of greenhouse and air pollutants into the air.

Due to lack of and inefficiencies in recycling programs, many shopping bags end up in landfills. Accordingly, the biodegradability of shopping bags needs to be of interest when managing the shopping bag dilemma. Biodegradability is one of the widely used measures of the environmental friendliness of shopping bags. Plastic bags are generally not biodegradable. This leads to major concerns regarding their disposal. It is known that plastic bags can exist for hundreds of years. They can fragment into smaller particles and pose significant risks to ecosystems and marine as well as wildlife.  Paper bag and generally biodegradable with cotton bags being more highly biodegradable due to the fact that they are made of natural fibre.

As the debate over the sustainability of shopping bags intensifies, it is important for shoppers to familiarise themselves with factors that add or subtracts to the environmental sustainability scores of available option. There is no single option that has no negative effect on sustainability. The choice is all about minimizing the negative impact. Reducing the need to use shopping bags needs to be the first point of consideration.

Highlight Image:
© Archer Fu via Unsplash

 Words:
Professor Mercy Mpinganjira
University of Johannesburg

Interview:
Tolga Rahmalaroglu
Luxiders Magazine