The recent decision by New York State to prohibit single-use plastic bags from retail stores makes it an ideal time to reexamine one of my favorite environmental quandaries. Plastic grocery bags were developed as a substitute for paper bags in the late 1970s. It was promoted as a way to save trees and prevent the cutting down of our forests.
The opinion that paper is superior to plastic for the environment is not really based on science or fact. It is based on misunderstandings about the way that plastic bags are made, how a landfill works and the assumption that non-biodegradable products are bad for the planet.
But what about cotton bags? According to Qz.com, they must be reused thousands of times before they equal the environmental performance of plastic bags. The Denmark researchers note that organic cotton is even worse than conventional cotton in relation to environmental impact. According to the article, organic cotton bags must be reused more times than conventional cotton bags based on the assumption that organic cotton has a 30% lower yield rate per acre than conventional cotton, and therefore was presumed to require up to 30% more resources like water, to grow the same amount. Everything we do, every bag, whether plastic, paper or cotton, has some kind of an impact on the environment.
But plastic bags are reusable. Some of the ways I reuse plastic grocery bags are as trash can liners, item storage and storing paint brushes for use the following day so they don’t dry out. With this ban, I will be forced to buy plastic bags for these purposes. So the ban on plastic bags will not reduce my use of plastic bags and will in fact create more waste and cost me money.
The discussion over the environmental impact of paper versus plastic has led to a number of life cycle assessment studies in Europe and North America. These evaluations show that regular plastic bags are much safer for the ecosystem than paper bags are.
In 2011, an Irish government research paper said that “it takes more than four times as much energy to manufacture a paper bag as it does to manufacture a plastic bag.” According to research, the manufacturing process also produces a greater amount of toxic chemicals when compared to making single-use plastic bags.
The Ontario Ministry of the Environment collected data that tracked the province’s plastic bag reduction program. It shows a 59.1% rate in the reduction in the use of plastic shopping bags. The United Kingdom’s Environmental Agency did a study of paper supermarket bags and found that they contribute three times as much to global warming than plastic shopping bags do.
A published Life Cycle Assessment, from EcoBilan, a division of Price Coopers Waterhouse, shows that in their manufacture, paper bags consumes over xxx times more energy than the manufacture of plastic bags. They also said that paper bag manufacture consumes over four times more water than the manufacture of plastic bags. Many studies agree that paper bags carry a substantial environmental impact in their manufacture that is not seen with plastic bags.
It is not easy to reuse paper bags because they have a tendency to tear and they get soggy when they get wet. Paper grocery bags are heavier than plastic bags. The typical plastic shopping bag weighs 0.28 ounces whereas a standard, 20 pound, Kraft paper, grocery bag weighs over 1¾ ounces. The largest and most significant result of changing from plastic to paper grocery bags will be the additional amount of volume and weight that paper bags will add to the solid waste stream. This additional amount will include a significant increase in the volume of greenhouse gas emissions that are generated to transport it to the landfills.
Plastic bags also play an unseen role in the conservation of the planet. In Canada, plastic bags are made from the ethane that is usually burned off during the natural gas refining process. Burning off this gas as opposed to using it to manufacture plastic bags also adds to the greenhouse gas in our atmosphere.
It takes only one truck to carry two million plastic bags but seven trucks to ship the same number of paper bags. The contrasts connected to plastic and paper strongly indicates why banning plastic bags won’t help. We are merely swapping one problem for another.
Case in point, in 2006, Taiwan rescinded a ban on plastic bags in their fast food sector. The ban led to an increase in the use of paper bags with a substantial increase in waste management costs and greenhouse gas emissions. Nothing is without a downside.
To be honest, a plastic bag doesn’t create very many problems just sitting in a landfill. The problem comes about when people don’t throw away their bags appropriately and the bags end up flying around in the wild, obstructing waterways and becoming a threat to wildlife. Rather than banning plastic bags, maybe we just should take personal responsibility and dispose of them properly. It is a shame that the government has to pass laws to get us to do what we should.