Is a plastic bag ban a win or a disaster for our lovely environment?
Depending on your orientation, your answer will be different. If you are among those who are calling for a ban on plastic, you will think this is a big win; but if you are a plastic scientist, or you work with plastic, you will see this as a disaster.
Regardless of where you stand, I believe you should also prefer that this question be answered by facts and logic, not by emotion and irrational sentiments.
Since we have both agreed that we should look for the answer based on facts and logic, I will try to present verifiable facts here so that you can then decide what you wish to believe.
An important point to note: Most of the bans are targeted at single-use plastics. Most of the reusable bags are also plastic bags.
Why are plastic bags hated by some?
Due to unbelievable social media and press activity, there has been a massive campaign against plastic bags (especially single-use plastics); due to this, normal people have come to believe that plastic bags are evil and should be eradicated from society.
There are many reasons why a lot of people believe that plastic bags (especially single-use plastics) are evil; in this article, I will like to explain 4 of those:
They are not a green solution
They cause litter
They pollute the ocean
They cause microplastics
Okay, let’s treat these complaints one by one.
They are not a green solution:
When they say that they are not a green solution, they mean that they aren’t friendly to the environment. But, to decide what is friendly to the environment, many probably don’t know that we have to turn to something called Life Cycle Assessment (LCA).
According to Wikipedia, “Life Cycle Assessment (also called Life Cycle Analysis) is a methodology for accessing environmental impacts associated with all the stages of the life cycle of a commercial product, process, or service.”
The purpose of an LCA is to determine the “cumulative potential environmental impacts” of a product with the purpose of using that knowledge to “improve the overall environmental profile of the product.”
To determine the LCA of a product, we need to take all factors needed to make a product into consideration; these include raw materials processing, manufacture, repair and maintenance, energy, transportation, usage, distribution, recycling, waste, disposal, etc.
Now that you know what LCA is, you should be curious to know the LCA of single-use plastic bags and how it compares with popularly preached alternatives such as paper bags, reusable bags, cotton bags, biodegradable bags, etc.
Let us look at 3 LCAs to see what they say. You can also search for more by using Google; just search for “plastic bags LCA,” “plastic bags vs paper bags LCA,” or "single-use plastic bag LCA."
LCA 1:
This research was done at Clemson university in 2014. You can download the free pdf here.
These are excerpts from the study:
“Paper bags are given preference, often to the total exclusion of PRBs, by most plastic bag legislation, by “organic” food stores, and by many environmentally conscious organizations and individuals. This preference originates because paper bags are perceived as coming from a renewable resource (trees), as being recyclable and as being compostable in an appropriate composting environment.”
“However, the data in the present study, in which the entire Life Cycles of both Paper bags and PRBs have been examined, show that Paper bags are more detrimental to the environment in ten of the twelve environmental impact categories studied and, on average, are 4 to 7.5 times more detrimental to the environment vs. PRBs.”
“Our results are based on a study of twelve environmental impact categories. Our results show that reusable LDPE and NWPP bags will have lower average impacts on the environment compared to PRBs if the reusable bags are reused for a sufficient number of grocery shopping trips. However, according to a recent national survey, a majority of consumers do not reuse their reusable bags for this sufficient number of trips, especially for LDPE bags. Moreover, 40% of people forget to bring their reusable bags with them to the store, and half the people who prefer NWPP bags used PRBs at their most recent shopping trip. In addition, only 15% of people follow the recommended cleaning procedures to ensure safe use of reusable bags.”
Our results also show that Paper bags, even with 100% recycle content, have significantly
higher average impacts on the environment than either of the reusable bags
or PRBs.
Note: PRBs refer to HDPE single-use plastic retail bags; LDPE refers to low-density polyethylene; NWPP refers to non-woven polypropylene.
Citation: Kimmel, Sc.D., Robert M., "Life Cycle Assessment of Grocery Bags in Common Use in the United States" (2014). Environmental Studies. 6.
LCA 2:
This research was done by Franklin Associates for the Council for Solid Waste Solutions in 1990. You can download the free pdf here.
Note: On the first page of this PDF, you will see that it includes several other LCAs of plastic bags.
These are excerpts from the study:
“The energy requirements for the polyethylene grocery sacks are between 20 to 40 percent less than for paper sacks at zero percent recycling of both sacks. As recycling increases for both polyethylene and paper sacks at the 2 PE:1 paper sack ratio, the energy requirements become equivalent at approximately a 60 percent recycling rate. At the 1.5 PE:1 paper sack ratio, the polyethylene sack continues to require 23 percent less energy than paper even at 100 percent recycling.”
“Polyethylene sacks contribute between 74 and 80 percent less solid waste than paper sacks at zero percent recycling. Polyethylene sacks continue to contribute less solid waste than paper sacks at all recycling rates.”
“At zero percent recycling rate, the polyethylene sack contributes over 90 percent less waterborne wastes than the paper sack. This percent difference actually increases as the recycling rate for both grocery sacks increases.”
“The landfill volume occupied by the polyethylene sacks is 70 to 80 percent less than the volume occupied by paper sacks based on 10,000 uses. These landfill volumes were derived from general material's landfill densities determined by Franklin Associates, Ltd. in conjunction with The Garbage Project, University of Arizona, Tucson. Further details of the volume estimates are contained in the section entitled Landfill Volume in Chapter 3.”
“Six components dominate the category of atmospheric emissions for paper and polyethylene sacks; particulates, nitrogen oxides, hydrocarbons, sulfur oxides, carbon monoxide, and odorous sulfur. For five of these six components, the polyethylene sacks produce less of each emission than the paper sacks. Hydrocarbons are generated in greater quantities by the polyethylene sacks.”
Citation: Resource and Environmental Profile Analysis of Polyethylene and Unbleached Paper
Grocery Sacks, Franklin Associates Ltd for the Council for Solid Waste Solutions 1990
LCA 3:
This study was conducted by the United Nations Environment Programme in conjunction with the Life Cycle Initiative (Economy Division) and the Government of Norway in 2020.
You can download the free pdf here.
Note: Paper bags are heavier than single-use plastic bags which is denoted by SUPBs.
These are excerpts from the study:
“Considering the impacts from all life cycle stages, the environmental ranking of bags varies between different environmental categories. The SUPB is a poor option in terms of litter on land, marine litter, and microplastics, but it scores well in other environmental impact categories, such as climate change, acidification, eutrophication, water use, and land use. The overall environmental ranking will depend on what environmental aspects are given the highest priority. In this context, it might be important to note that bags are responsible for a significant share of the litter, but a very small share of the total climate change when compared with other products and commodities.”
“Reusable bags can be environmentally superior to SUPBs if they are reused many times. For example, a cotton bag needs to be used 50-150 times to have less impact on the climate compared to one SUPB. A thick and durable polypropylene (PP) bag must be used an estimated 10-20 times, and a slimmer but still reusable polyethylene (PE) bag 5-10 times, to have the same climate impacts as an SUPB. This requires not only durability of the bags, but also consumers to reuse each bag many times.”
“Paper bags contribute less to the impacts of littering but in most cases have a larger impact on the climate, eutrophication, and acidification, compared to SUPBs. However, they can be better for the climate if the SUPB is heavy, the paper mills use renewable fuel, the paper bags are reused multiple times, and/or the waste bags are incinerated rather than deposited at landfills.”
“Biodegradable bags decompose and contribute less to the impacts of littering, compared to conventional SUPBs; however, the LCA results indicate they might be the worst option when it comes to climate impacts, acidification, eutrophication, and toxic emissions.”
Citation: United Nations Environment Programme (2020). Single-use plastic bags and their alternatives - Recommendations from Life Cycle Assessments.
I don’t want to bore you with too many details, but if you are willing to learn even more so that you can be enlightened about the truth, here are some more LCAs that you can read:
Life Cycle Assessment of grocery carrier bags, Environmental Project no. 1985, The Danish Environmental Protection Agency 2018
C. Edwards & J. M. Fry, Life cycle assessment of supermarket carrier bags: a review of the bags available in 2006, Report: SC030148, Environment Agency 2011
J. Sevitz, A. C. Brent and A.B. Fourie, An environmental comparison of plastic and paper consumer bags in South Africa: Implications for the Local Manufacturing Industry, SA Journal of Industrial Engineering,14(1): 67-82 2003
J. Morris & B. Seasholes, How Green Is that Grocery Bag Ban? An Assessment of the Environmental and Economic Effects of Grocery Bag Bans and Taxes, Reason Foundation 2014
LCA of shopping bag alternatives - Final Report, Hyder Consulting Pty Ltd for Zero Waste South Australia 2009
They cause litter:
Yes, there is no doubt that there is a plastic bag litter problem, but is that really a plastic bag problem or a human problem?
In his book titled Plastic Paradox, Dr. Chris DeArmitt has this to say about the litter problem:
“Let us imagine you are driving your car. It has 300,000 miles on it, and it finally stops working in the middle of the road. You get out and leave the car there to rust away. It is now a huge piece of worthless litter creating an unsightly mess in the environment. Who created that situation? Is the litter (i.e., the car) to blame? Most people would readily admit that the car cannot take the blame. I contend that it is exactly the same situation with every piece of litter, whether it’s a car, a cigarette butt or a candy wrapper. Every piece was left there by a human being. Blaming plastics for litter is equivalent to driving your car into a tree and blaming the car. It’s human nature to shift the blame, but that doesn’t make it right. Until we face that harsh reality, there will be no progress with our litter problem. This leads me to a related topic. I always see people blaming Coca-Cola or Unilever for litter. How unjust! In the example above, would you blame Ford or Volvo for abandoning your car? Would you demand that they pick it up and recycle it? No! Why then do people demand that Nestlé come to pick up candy wrappers?”
He also said this:
“The same argument can be applied to credit cards. They are small, easily misplaced pieces of plastic. According to the latest figures, each American adult carries more than two credit cards on average. That translates to over 300 million plastic cards all around the country. When was the last time you saw one on the sidewalk? When is the last time one washed up on the beach when you were on holiday? Do we see them clogging our rivers and sewers? We do not. These ubiquitous pieces of small plastic do not sprout legs or flippers and “make their way” into the environment. People act responsibly with these small pieces of plastic. The message could not be clearer: people cause litter.”
You can download the book here for free.
Apart from this, there is even statistical evidence to suggest that plastic bags don’t even have a large share of litter.
To prove this, I would like to quote from a plastic bag LCA study:
“A compilation of all of the statistically-based, scientific studies of litter in the U.S. and Canada over an 18-year period show consistently that “plastic bags” (which includes trash bags, grocery bags, retail bags, and dry cleaning bags) make up a very small portion of litter, usually less than 1%. Neither plastic bags nor Kraft bags are a significant component of roadway litter. Plastic bags are a very small component of litter found in storm drains and around retail areas.”
Source: Kimmel, Sc.D., Robert M., "Life Cycle Assessment of Grocery Bags in Common Use in the United States" (2014). Environmental Studies. 6.
They pollute the ocean
Without a doubt, every responsible member of society should be concerned about the welfare of the ocean - and by extension, the aquatic animals.
It is true that plastic pollution exists in the ocean, but there are 3 things I will like to point out.
Ocean pollution is a human problem.
Plastic bags aren’t as plentiful in the ocean as claimed.
Plastic bags don’t make up the largest share of ocean waste.
I already explained how litter is a human problem; this litter problem is also what results in ocean pollution.
As for the second point, the statistics pointing to gory pictures of plastic in the ocean have been said by many scientific reviewers to be false and inaccurate.
As for the third point, knowing the actual amount and percentage of ocean waste is practically impossible. Also, not only is it easier to discover plastic waste because of its lightweight characteristics which make it float, but it is also impossible to know just how much other materials (which don’t float) are lying deep at the bottom of the ocean.
Even if we are to use the plastics which are visible as a benchmark, plastic bags are still a low percentage of that.
To explain that, let me explain how plastic enters the ocean.
According to Ourworldindata.org:
“80% of the world’s ocean plastics enter the ocean via rivers and coastlines. The other 20% comes from marine sources such as fishing nets, ropes, and fleets. To tackle plastic pollution we need to know where these plastics are coming from. Previous studies suggested that a very small number of rivers were responsible for the vast majority of ocean plastics: 60% to 90% of plastics came from only ten rivers.”
“It is estimated that 81% of ocean plastics come from Asian rivers. The Philippines alone contribute around one-third of the global total.”
You can view the full report here.
Also, according to Earthwatch.org.uk, only 1% of all plastic waste in European freshwaters are plastic bags. You can read the report here.
In conclusion: We should do all we can to end ocean plastic pollution, but we should go about it in the right way and with the right knowledge so that we can see the intended results.
They cause microplastics
According to actual science, plastic bags can not possibly account for more than 1% of all microplastics in the oceans globally.
Microplastics that come from plastic bags are classified under secondary microplastics since they form as a result of the degradation of plastic bags. Earlier, I explained that plastic bags account for only 1% of freshwater waste; I also explained that waste from freshwaters account for about 80% of ocean waste. So if plastic bags account for 1% of freshwater waste, that will mean that plastic bags account for less than 1% of all ocean waste.
So let’s assume that all of those plastic bags degrade and form microplastics, it will still account for less than 1% of all microplastics in the ocean.
If you want to learn more about myths regarding microplastics, read the book "Plastic Paradox" by Dr. Chris DeArmitt. Download it for free here.
Conclusion
Irrespective of the material, we should all try to reduce pollution as much as possible. We should be more responsible citizens, and also try to learn more before making decisions so that we don’t end up worsening the situation that we want to rectify.
Our legislators and companies should take more time actually studying the effects of their laws and decisions before making them; they shouldn’t simply bow to popular opinion because of public pressure.
Littering should also be properly punished by the law so that we can reduce the massive pollution crisis that the world is facing.
Lastly, if our media companies truly love the environment as they claim to, they should properly scrutinize any information they receive before publishing them - they should remember that they are supposed to be a force for good, not for destruction.
Lastly, everyone should aim to be the change that they want to see. We should free ourselves from virtue-signaling and emotional decisions; this means that before we propagate anything or donate to a cause, we should always try to verify and be skeptical of the information that we receive lest we are deceived by the never-ending fake information that we consume daily.