The true impact of plastic bags compared to paper and reusable bags

The true impact of plastic bags compared to paper and reusable bags

  • Published: 17/10/2019
  • Updated: 18/10/2019
  • PlanetWood
  • Plastic Waste

The most sustainable choice will ultimately be down to you

As you probably know, there are many types of bags that can be used instead of those plastic carrier bags that have become a single use nightmare. Stopping to use plastic carrier bags and switching to other types isn't necessarily, on its own, the answer to the problem, but why?

Your actions will ultimately make the greatest difference, not the bag itself. The most sustainable choice is one that's sustainable for you.

Did you know that those pesky plastic bags that we used to get for free at the supermarket were not meant to be single use? They were in fact originally invented to replace paper bags as a more environmentally friendly alternative reusable bag..

You read that right - Plastic carrier bags were invented to be more eco-friendly!

In this article we are going to go over the history of the plastic bag and what environmental impact other types of bag have, such as those made from cotton, hemp, jute (hessain) and the reusable plastic "bag for life" types compared to a simple carrier bag that was never intended to create so much long lasting or life threatening damage.

So how did the carrier bag come into existence and why?

We go back to Sweden, 1959, where Sten Gustef Thulin was credited as inventing what he thought was the solution to the paper bag.

By designing what was referred to as the "T-Shirt Bag" due to it's shape, Thulin believed his product would become a positive solution to the huge amount of trees being chopped down to manufacture all those paper bags that were being used all around the world.

The carrier bag was designed to help the planet, not harm it.

The idea was simple. Thulin thought that by creating a bag that was both strong & light which could be used for a long time (reusable), that we wouldn't need to chop down all those trees to make paper bags that had a short life span. Paper bags were not very strong and wouldn't fare well in the rain either. The polyethylene carrier bag could change all this.

He never would have thought his creation would become the most commonly discussed item when the world talks about the huge waste problem we are facing today.

Thulin's plastic bag was supposed to be a reusable bag that could be used time and time again. Unfortunately, due to the bag increasing in popularity and use over the following decades because of their convenience, we also became lazy. Carrier bags became single use and now have massive health implications due to contaminating the whole planet.

Plastic bag waste has been found everywhere you can think of, from the darkest depths of the oceans right up to the highest point of mount Everest.

So plastic bags were more eco-friendly than paper bags?

Yes! The sad fact about it is, on the whole, they still are.

Here at PlanetWood we are not saying that continuing to use a plastic carrier bag is a good thing. It is way too late for that now. They are not readily recycled enough and we would never use those bags as they were intended and we must prevent them from polluting our planet and killing our wildlife.

However, that isn't to say that plastic carrier bags are not eco-friendly. When you consider the associated life cycle of a plastic bag and the alternative options you may be surprised with what you find out.

Looking at the larger impact of a product from production, it's usage and the recycling for re-use or re-purpose can highlight potential flaws in what consumers are lead to believe is environmentally friendly.

So let's compare polyethylene plastic bags with other bags made from paper, cotton, hemp, jute and those other plastic bags which are marketed as "bags for life".

A pulp mill in Nova Scotia Canada

A pulp mill in Nova Scotia Canada

Assessing the life cycle

There are various studies that have been conducted to assess the impact that plastic bag substitutes have. Some looked at the climate change impact while others have delved deeper into the full cycle.

These other extensive studies are called life cycle assessments. These assessments look at a wider range of factors such as the raw materials, the manufacturing process, transportation, and the eventual disposal.

The results of both are dramatically different. Lets start with a study from here in the UK that compared the climate impact of plastic bag alternatives.

To be eco-friendly have to use a reusable bag as much as possible

The UK study, found that to have a lower global warming potential than plastic bags:

- Paper bags should be used 3 times.
- Low-density polyethylene bags (the thicker plastic bags used in supermarkets) should be used 4 times.
- Non-woven polypropylene bags should be used 11 times.
- Cotton bags should be used 131 times.

The above would seem to show that it is straight forward enough how plastic bag substitutes can be more eco-friendly when used, as long as they are reused enough times.

Or is it that simple?

A Danish Life Cycle Assessment taking into account the extra factors mentioned above would show a remarkable difference in the amount of times a substitute bag would need to be used, including as a bin liner before being disposed of, to be as environmentally friendly than a single use polyethylene carrier bag:

- Polypropylene bags (the majority of reusable bags at supermarkets) should be used 37 times.
- Paper bags should be used 43 times.
- Cotton bags should be used 7,100 times - organic cotton would need a much larger number of uses.

It should be kept in mind that if a plastic bag is used more than once (i.e. as a bin liner before being disposed of) the number of times an alternative needs to be used increases. The above figures are based on a carrier bag being used to transport your shopping home and then being immediately discarded.

The figures are quite incredible.

So why are these figures so staggering?

Lets take a closer look at why paper and cotton bags need to be used so many times in comparison to a plastic carrier bag in order to have less of an impact on the environment.

Paper Bags

Isn't it odd now knowing that the plastic bag was invented to replace the use of paper bags? Paper instantly appeals to the eco-friendly side of your thoughts when you compare it to its plastic counterparts, but creating paper bags damages the environment too.

Many paper bags are not made from recycled paper and require the felling of trees, even if from a sustainable source. The energy and water used to create a paper bag is also much greater than that of a plastic bag.

So when you take into account the production cost, energy use, transportation and disposal process of both plastic bags and paper bags you have to use a paper bag 43 times more than a plastic one for it to be more eco-friendly.

Without mentioning names, we are sure you are aware of that popular high street clothing store where you will go and get given a great big paper bag for all your shopping? Yes, that's the one.

What can happen a few hundred yards up the road? You've got it! The handle breaks and tears the bag. There is no way that bag was going to last 43 uses. Would many other paper bags last that long either?

Maybe paper bags are not an ideal substitute to plastic bags from an environmentally friendly perspective after all. We can see why the plastic bag was invented in the first place.

Cotton Bags

Barb™ Recycled Cotton Drawstring Bag
Now cotton is natural and very sustainable. But it does have some major drawbacks as a plastic bag substitute due to requiring a large amount of chemicals to grow (unless organic). The most of any crop.

It is by far an eco-friendly material for bags if they do not get a huge amount of reuse. Luckily, cotton bags will last a long time if you treat them with care. A good thing considering that you would need to use one over 7000 times to offset the impact of using just a plastic bag once. Even more than this if the cotton is organic.

Here are some pros and cons about cotton bags:

Pros:

- Cotton is a biodegradable natural plant fiber
- Cotton is a renewable resource
- Cotton bags are strong, durable, soft, smooth and has a pleasant feel
- Cotton bags are widely available

Cons:

- Cotton bags have no resistance to moisture unless chemically treated
- Cotton requires high water consumption to grow
- Cotton accounts for 16% of the world's pesticides (not organic)
- Cotton bags are heavy, bulky and expensive to ship
- Cotton can suffer shrinkage if not washed cold and air dried

Take a look at our Organic, Recycled Barba™ reusable cotton tote shopping bags and the Barba™ cotton drawstring bags.


Hemp Bags

Hemp grows very well without chemicals and is drought tolerant so does not need as much water like cotton does.

Each acre of hemp can yield between three to six tonnes of dry fiber. These fibers are one of the longest, strongest and most durable fibers which are also much stronger than cotton.

Pros:
- Hemp is very strong, durable, and is also rot resistant
- Hemp can grow in poor soils with little water
- Refined hemp is soft, smooth and pleasant to touch
- Hemp is less likely to suffer shrinkage when washed
- Hemp gets stronger over time and with increased use
- Hemp can be combined with other materials to make highly desirable fabrics with a texture similar to linen

Cons
- Hemp is not produced in the western world and will need to be imported
- Hemp can be an expensive material
- Hemp can be grainy if not refined.
- Refined hemp uses a lot of water to produce.

Jute Bags

Jute is a natural plant fiber also called hessian or burlap.

Pros:
- Jute is a natural renewable resource
- Jute is biodegradable and compostable
- Jute is durable
- Jute grows in areas with high levels of rain and requires little to no chemicals
- Jute can be combined with other fabrics

Cons:
- Jute is not very resistant to moisture unless chemically treated or laminated
- Jute has a grainy texture

Polypropylene Bags

These are your "bags for life".

This material is a form of plastic and is a flexible resin polymer. Non-woven polypropylene bags are regarded as the best reusable shopping bags due to their low cost and relative durability.

Pros:
- Polypropylene is recyclable
- It is very strong
- It can be made from recycled materials
- It is chemical resistant
- It can be woven, making it less porous and easier to wipe clean
- Can be made into a variety of color options

Cons:
- It is still a type of plastic
- It is not biodegradable or compostable
- It is a product of the petrochemical industry just like carrier bags
- It is not made from a renewable resource

Conclusion

As you can see and as we said at the beginning of this article, your actions will ultimately make the greatest difference, not the bag itself. The most sustainable choice is one that's sustainable for you.

If you choose the right bag for what is best for you to get as much reuse out of it as is possible, we feel that this is the most sustainable choice.

Every manufactured product will have its pros and cons with regard to its effect on the environment.

When it comes to choosing what type of bag to use the key thing to consider is how much

Paper as a substitute for plastic