Paper Bags Versus Plastic Bags

As grocery shoppers we are often faced with the choice between paper bags or plastic bags. Which is the more environmentally responsible choice? Well, turns out they have about an equal number of pros and cons.

Paper Bags

Paper bags have been around since the mid 1800's and have been used in grocery stores long before the plastic bag entered the scene in the 1970's. Margaret Knight, who founded the Eastern Paper Bag Company in 1870, is regarded by most as the mother of the paper grocery bag.

It takes more than four times as much energy to manufacture a paper bag as it does a plastic bag. This includes energy expended in harvesting trees, converting the wood to pulp, conversion to paper, cutting, printing, packaging, and shipping.

Paper production involves large quantities of toxic chemicals such as sulfurous acid which contributes to both air pollution and water pollution. It's estimated that paper bag production generates 70% more air and 50% more water pollutants than plastic bag production.

Plastic Bags

Plastic shopping bags first appeared in 1974 when Sears and JC Penney made the switch from paper to plastic. Within a few years, supermarkets were offering customers the choice between paper or plastic.

About 80% of all grocery bags in the U.S. are plastic. That's about 100 billion plastic bags a year, made from an estimated 12 million barrels of oil. The average family accumulates about 60 plastic bags in only for trips to the grocery store.

The majority of plastic bags are made from polyethylene, which in turn is derived from petroleum. The polyethylene production process involves the use of many toxic chemicals, some of which produce the most hazardous waste.

Recycling Rates

Although paper bags have a higher recycling rate than plastic bags, recycling rates of both are very low: 1-3% for plastic and 10-15% for paper. Paper recycling requires much more energy then plastic recycling because it must be returned to pulp using many chemicals to bleach and disburse the fibers. Most recycled bags are turned into cardboard rather than new paper bags.

Biodegradability

Paper is more biodegradable than plastic. However, because the effective breakdown of paper requires plenty of water, sunlight, and oxygen, most bags buried in modern landfills are not likely to degrade any time soon because they are buried so deep.

Plastic bags take much longer to degrade (not biodegrade) than paper bags. Under the best circumstances, high density polyethylene will take more than 20 years to degrade. In less ideal circumstances, such as in a landfill, it will likely take more than 1000 years for the plastic to degrade. The only good news is that plastic bags take up less space than paper bags in landfills.

Stray plastic bags are found almost everywhere on the planet causing unsightly litter, clogging sewers and other drainage pipes and posing a threat to marine life when ingested. It's estimated that plastic bags are the second most common type of ocean refuse after cigarette butts. According to the UN, 10% of the plastic produced every year winds up in the ocean, 70% of which ends up on the ocean floor where it will likely never degrade.

Other Considerations

A high quality reusable shopping bag made from cloth or even recycled plastic has the potential to eliminate an average of 1000 plastic bags over its lifetime. Perhaps this is the most viable answer to the paper versus plastic question.