Learn about the history and environmental impact of plastic bags.
Despite their ubiquitous nature, plastic bags are a relatively new invention. The first plastic bag appeared in the form of a sandwich bag in 1957. The bags advanced from sandwiches to produce in 1969 and have been used for groceries since 1977. Sturdy plastic garbage bags made their debut in the 1960s. In 1974, department stores began sending consumers on their way with merchandise in thick, glossy plastic bags.
Environmental concerns spurred plastic bag recycling programs and grocery stores have been offering plastic bag recycling nationwide since 1992. Most plastic bags are fully recyclable and some are biodegradable. Despite the emergence of plastic bag recycling programs, Americans discard an estimated 100 billion plastic bags every year, according to the Worldwatch Institute. Less than one percent of plastic bags are deposited with a recycling program, according to the institute, although many consumers find other uses for the bags, such as lining trash cans and picking up after pets, before discarding them.
The word plastic first appeared in 1909, although plastic products did not gain popularity until after World War I, according to Chemical and Engineering News. Following the war, petroleum became more readily available. Along with natural gas, petroleum is one of the primary sources of plastic's key ingredients. Plastics are made from polymers, and plastic bags are composed of ethylene molecules that have been polymerized. The final product is called polyethylene.
The composition of a plastic bag determines its thickness and overall durability. Plastic bags are generally made from three types of polyethylene. Thin, flimsy plastic bags commonly used by dry cleaners are made from low-density polyethylene. Grocery store plastic bags are slightly thicker and composed of high-density polyethylene. Thick, glossy plastic bags, typically used by department stores and other retailers, are made from linear low-density polyethylene. When the polymer chain of the polyethylene is branched, the resulting plastic bag is thin and flimsy.
Because plastic bags are handed out to consumers so freely, millions of plastic bags wind up as litter every year, according to National Geographic. Discarded plastic bags pose a threat to wildlife, particularly sea turtles that ingest the bags, clog streams and storm drains, and become tangled in manmade objects such as power lines. Scientists suspect plastic bags can take as long as 500 to 1,000 years to fully decompose, according to Slate; however, the number is only an estimate because the bags are too new of an invention for recorded data. As plastic bags decompose, the petroleum in the polyethylene seeps into soil and waterways, causing contamination.
Despite the negative impact on the environment discarded plastic bags pose, many types of plastic bags are fully recyclable. Also, manufacturing plastic bags demands fewer resources than paper bags. According to PlasticBagRecycling.org, it takes 40 to 70 percent less energy to manufacture plastic bags and 91 percent less energy to recycle one pound of plastic versus one pound of paper. Plastic bag production requires about four percent of the water required to produce paper bags.
China, Ireland and Australia are several of the countries that have imposed bans or taxes on the use of plastic bags. The reasons for discouraging the use of bags vary depending on the individual countrie's environmental situations. China's ban was enacted shortly before the start of the 2008 Summer Olympics. Several cities in India prohibit plastic bags because they clog storm drains leading to floods. Excessive pollution in South Africa inspired a ban on thin plastic bags and taxes on thicker bags.
San Francisco and Oakland in California are some of the U.S. cities following the banning trend. Other California municipalities require grocery stores to take back the plastic bags for recycling. Several U.S. cities, including New York City and Seattle, are considering or have already imposed a plastic bag tax, which has seen success in Ireland. In an effort to discourage plastic bag use, some earth-friendly retailers offer a discount to consumers who bring their own bags.
Many grocery stores and other retailers now sell inexpensive reusable cloth bags as an alternative to both paper and plastic bags. Other plastic bag alternatives include backpacks, baskets, plastic boxes and loading items into the car directly from the shopping cart without the use of any bag or box. Consumers can also refuse plastic bags when the items can easily be carried out of the store.