They're roughly equal in pros and cons. While they are seen as convenient and readily available, they place an unneeded demand on natural resources and cause significant pollution on land and in water. Not to mention that both create toxic by-products during their life cycles and neither is effectively recycled.
Here are some hard facts surrounding the age-old question when it comes to grocery shopping, and why using reusable shopping bags seems like a no-brainer.
- It is estimated that somewhere between 500 billion and one trillion plastic bags are consumed throughout the world each year.
- It takes more than four times as much energy to manufacture a paper bag as it does to manufacture a plastic bag.
The truth about plastic
Most plastic bags are made from a type of plastic called polyethylene
. Eighty percent of polyethylene is produced from natural gas — an abundant, yet non-renewable resource. Polyethylene, as a raw material, can be manipulated into any shape, size, form or color. It’s watertight and can be made UV resistant. It can be printed on and reused many, many times. In most cases, it can be recycled but is not considered "cradle to cradle," meaning it cannot be recycled over and over nor returned to an organic state.
The biggest energy input for the plastic bag creation process is electricity, which, in this country, comes from coal-burning power plants at least half of the time; the process requires enough power to heat the oil up to 750 degrees Fahrenheit, where it can be separated into its various components and molded into polymers.
When plastic has been used, it can go to one of two places: The landfill or the recycling center. Plastic
can be recycled, but it isn't simple or easy. Recycling involves essentially re-melting the bags and re-casting the plastic; manufacturing new plastic from recycled plastic requires two-thirds of the energy used in virgin plastic manufacturing. Unfortunately, the quality isn't quite as good the second time around, seeing as the polymer chains often break leading to a lower-quality product.
Harm to wildlife
Plastic bags pose a threat to marine life, because, if ingested, the bags can block the stomach and cause starvation. Sea turtles, for example, mistake plastic bags for jellyfish.
About 100,000 animals such as dolphins, turtles, whales and penguins are killed every year due to plastic bags. Many animals ingest plastic bags, mistaking them for food. And worse, the ingested plastic bag remains intact even after the death and decomposition of the animal. Therefore, it lies around in the landscape where another victim may ingest it. Other animals or birds can become entangled in plastic bags and drown or are unable to fly. Greenpeace
reports that at least 267 marine species are known to have suffered from getting entangled in or ingesting marine debris. Nearly 90 percent of that debris is plastic. The use of reusable bags helps prevent plastic waste in the ocean because reusable bags are used over and over and are not littered often like plastic bags.
Pros and cons of recycling paper
Paper comes from trees, and the pulpwood tree industry is large. The production process creates a tremendous scar
in the forests for both plants and animals. It can take over a century for nature to recover from even a small logging operation.
Paper sacks generate 70 percent more air pollutants and 50 times more water pollutants than plastic bags.
It takes 91 percent less energy to recycle a pound of plastic than it takes to recycle a pound of paper. But recycling rates of either type of disposable bag are extremely low, with only 10 to 15 percent of paper bags and one to three percent of plastic bags being recycled.
To reuse paper bags, the paper must be returned to pulp — a very intensive process that involves numerous chemicals and the use of a lot of energy.
Another factor to consider is water pollution
. The making of paper, whether virgin or recycled, uses many thousands of gallons of clean water that can soon become polluted in the papermaking process. Virgin paper creates 35 percent more water pollution than recycled paper. Recycled paper also creates 74 percent less air pollution than virgin paper. However, both types of paper can contribute to contaminating area waters. Scientific evidence shows that fish can experience adverse effects through chemicals that reside in sediment. It can more than three years for any level of toxicity to lower.
The final decision: Paper or plastic?
Both paper and plastic bags consume large amounts of natural resources and the majority will eventually end up in the landfill
. Both bags can be recycled to some extent and can be utilized around the house. I've read several studies comparing the two choices and none of them seem to agree on this issue. Some feel plastic is the better overall choice, others vote for paper. Paper may consume more resources to produce, however, it is also more recyclable than plastic if you include the fact that paper can be composted and plastic bags cannot. In my opinion, neither one is the "better choice," seeing as the best choice overall is to use a reusable bag. Depending on the style, they'll hold 25 to 40 pounds and last for years. Most can be machine washed and can be kept in the car, glove compartment, purse or backpack. If your local supermarket gives you five cents per bag every time you use them, and you buy groceries once a week, it'll pay for itself in about a year and a half!
Many countries around the globe and many cities here in the U.S. are banning the use of plastic bags at checkout or are charging for them. This makes the adoption of reusable bags an even easier choice.
Blue bag: gooseflesh/Flickr
Bag floating: Bag Monster/Flickr
Brown bags: MrTakeOutBags/Flickr
Reusable bag: arlia flower/Flickr