You think plastic bags are harmless? Tell that to the dolphin with the plastic bag wound around its snout, slowly starving to death. You think they’re light, easily thrown out? Over one million bags a week are buried, ditched and dumped in our country. A couple of plastic bags blowing in the wind couldn’t hurt, could it? Potentially putting our environment at risk of damage, and affecting the clean green nature of New Zealand.

Dangers Of Using Plastic Bags Environmental Damage
Plastic bags have been known to cause a lot of environmental damage. A single plastic bag can take up to 1000 years, to decay completely. This makes the bags stay in environments longer, in turn leading to great build-up on the natural landscape (much more than degradable materials like paper). In other words, the more plastic bags you use, the greater the chances of environmental damage. Threat To Animal Life
As per Marrickville Council of Australia, as many as 100,000 whales, turtles and birds die have been reported to die every year, mainly because of plastic in their environment. Plastic bags not only have adverse effects on our natural habitats, but have also been found to be responsible for the death of many animals, mainly on account of the suffocation encountered on eating them. Suffocation
Not only animals, infants and young children have also been reported to have lost their life, on account of plastic bags. Since plastic bags are thin and airtight as well, children often end up blocking their mouths and nostrils with them. In case they are not being monitored by an adult, this leads to suffocation and, in some cases, even death. Pollution
Plastic bags are extremely durable. In case you are thinking of this as an advantage, just bring to mind an image of the huge landfill that you visited on the city outskirts, the other day. In most probability, majority of the rubbish present there will comprise of plastic bags only. In other words, plastic bags have led to a great increase in the pollution levels. Fumes
Since plastic bags are not bio-degradable, the only way to get rid of them is to burn them up. Though lighting a match to them is easy, it has more than its fair share of disadvantages. The biggest of them is that smoldering plastics can release toxic fumes into the environment, in turn taking the air pollution to much higher levels. Non-renewable
One of the main disadvantages of plastic bags is that they are not renewable. The reason behind this is that they are made of petrochemicals, a non-renewable source of energy. They can be recycled, but not as easily as paper bags. Plastic bags can last for as much as hundred of years. In other words, long after you are no more, the plastic bag used by you will be in existence.
Non-Biodegradable
Estimates of the number of plastic bags used around the world each year vary in range from 100 million to a trillion according to a New York Times article. Since only a small portion of these bags is recycled, many plastic bags are left to enter the waste stream. The bags will likely take about 1,000 years to decompose. Because such a large number of bags are produced and it takes a long time for them to decompose, the plastic bags that are thrown away create a lot of waste in the landfills on top of the trash that may be inside of them.
Of the 1 billion plastic bags distributed every day on our planet, 0.2 to 0.3 percent — millions, in other words — end up in the ocean. Bags, along with other forms of plastic, float on the surface, where they’re often mistaken for food by turtles, birds and other marine life.

Several studies have investigated plastic ingestion by sea turtles, including one in 1993 that found debris in the digestive tracts of 51 percent of examined loggerheads. Some necropsies (animal autopsies) have found turtles whose entire digestive tract was packed solid with pieces of plastic bags. In fact, more than 260 marine species have been documented as ingesting or becoming entangled in plastic.
Every year, more than 500 billion plastic bags are distributed, and less than 3% of those bags are recycled. They are typically made of polyethylene and can take up to 1,000 years to biodegrade in landfills that emit harmful greenhouse gases.

http://imageary.com/wp-content/uploads/clean-up-australia-plasticbags-household.pdf http://ken-foundation-awareness2.blogspot.co.nz/p/say-no-to-plastic.html Did You Know...?
The average plastic bag is used for only 5 minutes, yet can take up to 1,000 years to break down in the environment.
Australians use over 10 million plastic bags a day.
Almost half of these bags are given away by non-supermarket retailers such as newsagents, discount stores, pharmacies, fruit and vegetable shops, liquor stores and take-away outlets.
Plastic bags suffocate, disable and kill thousands of marine mammals and sea birds worldwide each year. When the animal dies and decays, the plastic bag is free again to repeat the deadly cycle.
It only takes 4 grocery trips for an average Australian family to accumulate 60 plastic shopping bags.
Australians throw away about 7,150 recyclable plastic bags a minute, with 429,000 recyclable plastic supermarket bags dumped in landfill every hour.
Plastic bags are considered to be a 'free' commodity, but the cost to households of $10 to $15 per year is added to the price of goods that they purchase.
The production of plastic bags accounts for some 20,000 tonnes of plastic polymer derived from non-renewable resources. While plastic bags can be recycled, only a tiny proportion of plastic bags are collected and reprocessed.
Plastic has remained the most common category of rubbish picked up on Clean Up Australia day over the last 20 years. Most common plastic consumer items include chips / confectionery bags, bottle caps and drink containers.

Our planet Earth is beautiful but fragile. Even the slightest of mishandling and negligence of things can destroy it to bits. It is not necessary that it will be destroyed suddenly, But it will take time and eventually it will ‘Die’.
The topic on which I am going to write about is a very serious issue and probably most of you know about the fact that how dangerous these plastic bags are.
The plastic bags are not bio-degradable and it is thought that it will take about a 1000 years for a plastic bag to disintegrate in to smaller particles, even then it would continue to be a serious threat and will continue to pollute soil and water.
Many of you may think that these plastic bags can be discarded in the landfills, but my dear friends, ‘The danger out of sight is still a danger’.
If we discard the plastic bags in the land then it is like saving ourselves and ‘Choking the earth to death’. One may even call it a murder!
The other problem is that about 3 trillion plastic bags are produces every year and its manufacture takes millions of gallons of our fuel, which it self is running out fast. It can be basically saved and hence it can be used for transportation and heating.
Now to talk some things about the facts and figures.
As I just mentioned that about 3 trillion plastics bags are manufactured each year, USA alone uses about 100 billion plastic bags per annum, but China leads the pack by some distance, In China about 3 billion of these plastic bags are used daily and are thrown away after use, The total pieces of these plastic bags floating in every square mile of our oceans is about 46000, To talk about the whole world, More than 1 million plastic bags are used every minute.
These facts send shivers down my spine. I also use these bags but you see its the time to change, Many countries have had strict actions being taken against the production of these bags and the situation is getting better but still the lack of awareness is perhaps getting the better of us and everyday the demand is increasing.
Still I am happy to see that in my country, Some super markets don’t give plastic bags and instead use the bags made of cloth. It is really a good idea to replace these plastic bags with the bags made up of cloth.
Now how can I forget the danger these plastic bags have for the animals, millions of animals die each year just by swallowing these plastic bags, mistaking it for food. They ultimately end up choking to death.
Just think about it for a while before your own pet dog, whom you love so much chokes to death by swallowing a piece of the plastic bag which you had just thrown away after coming back from the market!
The time has come when we really think about it and the super powers, in fact all the countries of the world come together to ponder on this thing before it is too late.
As for us, I think it is a high time to make a choice, that either we want our easiness or we want a future, a friendly environment, our mother nature for our generations to come…

Because they are a waste problem that harms the environment:

Every year 4 million New Zealanders use 1 billion plastic shopping bags and 20 million Australians use approximately 5.6 billion.
A person's use of a plastic check-out bag can be counted in minutes - however long it takes to get from the shops to their homes. Plastic bags however, can take between 15 and 1000 years to break down in the environment.
In the marine environment plastic bag litter is lethal, killing at least 100,000 birds, whales, seals and turtles every year. After an animal is killed by plastic bags its body decomposes and the plastic is released back into the environment where it can kill again.
A Bryde's whale died on a Cairns beach after ingesting 6 square metres of plastic - including plastic bags. Such obstructions in animals can cause severe pain, distress and death.
On land, plastic bag litter can block drains and trap birds. They also kill livestock. One farmer near Mudgee NSW, carried out an autopsy on a dead calf and found 8 plastic bags in its stomach. The loss of this calf cost the farmer around $500.
Plastic bags are not free to consumers - they are actually adding an estimated NZ$25 million and A$173 million a year to New Zealand and Australia's grocery bills.
The amount of petroleum used to make one plastic bag would drive a car about 115 metres. The 6.9 billion plastic check-out bags we use every year is enough to drive a car 800 million kilometres or nearly 20,000 times around the world.
At least 16 million plastic bags end up as litter on our beaches, streets and parks. New Zealand local and State Governments spend $$ millions a year picking up litter.
Not all litter is deliberate. 47% of wind borne litter escaping from landfills is plastic - much of this is plastic bags.
Over 40,000 plastic check-out bags are dumped in landfills every hour in New Zealand and 200,000 are being dumped in Australia
Only 5% of Australia's plastic bags are currently being recycled, despite recycling facilities being available at major supermarkets.
In many council areas, plastic bags are the single main contaminant of kerbside recycling.
Plastic bags are a by-product of the oil industry. 5 billion HDPE plastic bags are imported into New Zealand and Australia every year.
Since March 2002, Ireland has reduced its plastic check-out bag usage by 90% and in April 2003 Coles Bay in Tasmania successfully banned plastic check-out bags in all their retail stores. In the first twelve months, Coles Bay stopped the use of 350,000 plastic check-out bags.
In Australia, over 10 million reusable bags have now been sold by Coles, Woolworths and Safeway stores. At only $1 each, they're a cheap way to save Australia's wildlife!

Problems include:
Take hundreds of years to decompose
Littering of landscapes and waterways
Threaten wildlife (particularly marine life such as turtles)
Release toxic gases when burnt

Finally, plastic bags should be banned because they are not as easily disposed of as some people think. They pollute the land and the sea.