Friday, 22 June 2012


Plastic shopping bags, carrier bags or plastic grocery bags are a type of shopping bag made from various kinds of plastic. In use by consumers worldwide since the 1960s, these bags are sometimes called single-use bags, referring to carrying items from a store to a home. However, reuse for storage or trash is common, and modern plastic shopping bags are increasingly recycable or biogradable.

Traditional plastic bags are usually made from polyrthjylene, which consists of long chains of ethylene monomers. Ethylene is derived from natural gas and petroleum. The polyethylene used in most plastic shopping bags is either low-density (rein identification code 4) or, more often, high-density  (resin identification code 2). Plastic shopping bags are commonly manufactured by blown film extrusion.

Some modern bags are made of vegetable-based biopl;astics,  which can decay organically and prevent a build-up of toxic plastic bags in landfills and the natural environment. Bags can also be made from degradable polyethylene film. However, most degradable bags do not readily decompose in a sealed landfill and represent a possible contaminant to plastic recyling operations.

Plastic shopping bags however could be made from polylatic acid which is a biodegradable polymer derived from llactic acid, although this is not widely used. In general, biodegradable plastic bags need to be kept separate from conventional plastic recycling systems. One way to do that is to give them a distinct colour.

According to Vincent Cobb, a manufacturer of reusable bags, each year millions of discarded plastic shopping bags end up as litter in the environment when improperly disposed of. The same properties that have made plastic bags so commercially successful and ubiquitous—namely their low weight and resistance to degradation—have also contributed to their proliferation in the environment. Due to their durability, plastic bags can take centuries to decompose.

On land, plastic bags are one of the most prevalent types of litter in inhabited areas. Large buildups of plastic bags can clog drainage systems and contribute to flooding that occurs almost annually in Manila. There are more than 8,000 metric tons of plastic garbage collected daily in Metro Manila. What is alarming to the people of Manila is that the plastic products clogging the already inadequate drainage system can result in massive flooding in the event of continuous and prolonged heavy rains lashing Metro Manila. The floods are in large part the result of the capital's poor drainage and sanitation systems, which have been neglected by several successive administrations in power. When it rains heavily down upon Manila, sewers are clogged up by plastic bags and other refuse leading to roads which then becoming rivers and gardens become lagoons. Obviously the authorities in Manila have to find another way of the citizens of that city from disposing of their garbage via their drainage system. Bangladesh has the same kind of problem.

Plastic bags have been found to constitute a significant portion of the floating marine debris in the waters around southern Chile in a study conducted between 2002 and 2005. If washed out to sea, plastic bags can be carried long distances by ocean currents, and can choke marine animals. Obviously that country has to keep their plastic bags away from the sea.

Littering is often a serious problem in developing countries, where trash collection infrastructure is less developed than in wealthier nations. The relatively limited adoption of modern biodegradable plastic bags means that many older landfills are filled with large, persistent deposits of non-degrading bags

Heavy-duty plastic shopping bags are suitable for reuse as reusable shopping bags. Lighter weight bags are often reused as trash bags or to pick up pet feces or place food scraps into them. All types of plastic shopping bag can be recycled into new bags where effective collection schemes exist.

By the mid-2000s, the expansion of recycling infrastructure in the United States yielded a 7% rate of plastic bag recycling. This corresponded to more than 800,000,000 pounds (360,000 tonnes) of bags and plastic film being recycled in 2007 alone. Each ton of recycled plastic bags saves the energy equivalent of 11 barrels of oil, although most bags are produced from natural-gas-derived stock. In light of a 2002 Australian study showing that more than 60% of bags are reused as bin liners and for other purposes, the 7% recycling rate accounts for 17.5% of the plastic bags available for recycling.

Los Angeles became the largest city in the nation  to approve a ban on plastic bags at supermarket checkout lines, handing a major victory to clean-water advocates who sought to reduce the amount of trash clogging landfills, the region’s waterways and the ocean. That isn’t the only community that bans plastic bags. Plastic bags are either restricted or completely banned in over a quarter of the world's countries.

There was a time when we who were grocery shopping were given paper bags to carry our groceries out of the store. But when we placed them on the wet ground to open our car doors, the bottoms having become soggy, weakened and everything in the bag spilled all over the pavement. Further, carrying the groceries home in a paper bag on a rainy day resulted in the bags disintegrating and everything in them falling to the ground long before we reached our homes. Plastic bags are extremely strong. You can put heavy objects in them and the bags won’t break open. I am not convinced that you can do the same with paper bags, no matter how much they are reinforced.

The city of Toronto is another large city that wants to prevent plastic bags from being sold in stores. What follows are the reasons why most of the city counselors want the plastic bags banned.

1        It’s good for the environment. A ban means more people will use reusable bags since shoppers won’t be wasting precious non-renewable resources like oil to make plastic bags or create the pollution that comes from manufacturing and disposing of plastic bags. It would also mean that no more disposable plastic bags would be good news for wildlife who often suffer from plastic bags polluting their habitat.

2         It will save Torontonians money. Figures from city staff suggest that the 5-cent fee cut bag use by 50 per cent and recycling costs to the city by at least $100,000. A ban could likely add another $100,000 in savings from reduced recycling and disposal costs. Add to this the savings from reduced litter collection costs and as much as over $200,000 in costs could be saved.

3.        Banning plastic bags will reduce litter. Plastic bags litter city streets, get caught in tree branches and float in rivers, streams and the lake. A ban will eliminate this form of litter.

4.        Since the 5-cent fee started, use of disposable plastic bags has fallen anywhere from 53 per cent to 80 per cent, according to various studies. Many Torontonians have switched to reusable bags and don’t need disposable plastic bags.

Now I will comment on what I think about these observations.

1.         Whenever I go into a grocery store that offers its customers the option of buying a five cent plastic bag to carry their groceries in, almost all of the customers I see choose to buy those bags. I am one of them. However, I realize that I should keep some of the empty ones in my car so that when I go into the grocery store again, I already have a plastic shopping bag. It would save me five cents each trip (or more depending how many I need each trip) I do see customers coming in with canvas bags and strong paper bags with handles but not as often as I would like to see.

With respect to the cost of making them, such as using oil, it goes with the territory. If we can find ways of not using oil in anything we use it for, it would be great but that isn’t going to happen for quite a long time. As to the pollution created by making plastic bags, I don’t accept that as valid reason for banning them. Everything that is manufactured creates some form of pollution. For example, manufacturing car batteries because they use lead creates a form of pollution but until we find an alternative metal for our batteries, we will have to live with it.

I am not convinced that plastic bags pollute the habitat of wild animals. It does in some instances but not that often.

2.       If it costs the City of Toronto $200,000 a year to deal with recycling and disposing of plastic bags, then perhaps another five cents added to the price of a plastic bag that the customer had to pay will pay for the cycling and disposal costs.

3.       I think the statement that plastic bags litter streets, are seen in trees and floating in rivers and lakes is hyperbole. I have yet to see a plastic bag floating in a river or lake in Canada and in Ontario alone, we have tens of thousands of them.

4.         I don’t accept the claim that as many as 58 to 80 percent of consumers have switched to using non plastic bags. When I go into a store, I see almost all of the customers purchasing them.

Plastic bags can be used for other purposes other than for customers carrying home groceries or other products home with them. In our home, we place wet garbage in them so that when we close them and place them in the garbage container that is used to hold only wet garbage, when the garbage men come by and empty the garbage container and leave it on our sidewalk for us to bring back into our garage, it doesn`t smell or attract insects. Mothers can place used disposable diapers in them. When we go on a trip, we place our used garments in them so that they are separated from the rest of our clothes. They are also great for placing wet bathing suits in when you are heading home right after a swim. Paper bags would never be suitable for these purposes. 

I do believe that we should encourage customers to bring their unused plastic bags with them when they are shopping or other bags of strong material. That way, there will be less reason to always be buying plastic bags.

Instead of banning the use of plastic bags outright, perhaps we should pay ten cents a bag. And if we need three plastic bags to carry our groceries home, we will pay thirty cents instead of fifteen cents. That will encourage us to reuse our plastic bags we bought earlier more often. Five cents can be applied to environmental projects; five cents can go to the store that has to buy them and the remaining five cents to the manufacturer. There will be less plastic bags having to be manufactured and also less plastic bags being thrown out simply as garbage but this way, everyone benefits.

If vegetable-based bioplastic bags which can decay organically and prevent a build-up of toxic plastic bags in landfills and the natural environment can be made waterproof and be reinforced as to not fall apart when groceries and other goods are placed in them, then we should use them as a suitable alternative to using plastic bags.

UPDATE: The City Council of Toronto changed its mind and voted that plastic bags can be sold for 5 cents each in grocery and other stores to carry goods out of the stores. 

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