Every year, 1 billion plastic shopping bags are used by 4 million New Zealanders. A person's use of a plastic check-out bag can be measured in minutes, depending on how long it takes them to go from the store to their house. But the life of a single-use plastic shopping bag can be longer than you might think - some of them are still being used years after they were first placed in the rubbish.
New Zealand is one of the highest per capita users of plastic shopping bags. The number of people who use these bags each year is likely to increase as retail sales growth outstrips population growth. In fact, the number of people using plastic bags in New Zealand has increased since 2013 when data collection began. This page will be updated when new data becomes available.
What are the environmental impacts of using plastic bags? There are two main issues with using plastic bags: waste and climate change. Plastic bags are made from oil, which gets extracted from natural sources like trees or mined from old oil wells. As well as causing environmental damage while they are being produced, this also puts additional pressure on the environment once they have been disposed of.
"The average American family takes home almost 1,500 plastic shopping bags a year" (NRDC). That's about 20 bags a month, or 3 bags every other day. It's also about $180 million worth of plastic bags.
Here are some more facts about bag usage:
• Plastic bags take 1000 years to decompose. Organic waste such as fruits and vegetables should be placed in organic compost instead of in the regular trash can. Composting helps break down these materials and produces an enriched soil that is good for gardening.
• Plastic bags pollute our landfills or incinerators. Landfills and incinerators emit toxic chemicals into the air we breathe. These emissions are known carcinogens which can cause cancer over time.
• Plastic bags are harmful to animals. Animals eat them by accident or intentionally to stuff their guts with the bags' contents - usually food scraps. This causes intestinal blockages that can lead to death.
• Plastic bags take hundreds of years to disappear from the environment. They don't biodegrade; they disintegrate. The material becomes part of the water cycle, which means it returns to earth in the form of rain or snow.
Each trip to the grocery shop in the United States results in the accumulation of 15 plastic bags by the average family. If they shop once a week, that's 780 bags each year! (Some estimates are much higher!) Instead of using plastic bags, bring your own reusable shopping bags. If everyone did this, it would make a big difference for the environment.
The number one reason people give for not bringing their own bag is that they feel like they're being asked to pay too much for paper bags. But if you look at the statistics, you'll see that buying recycled paper bags is actually more environmentally friendly than using plastic ones. And since they can be used for many things other than just shopping, they may even save you money in the long run!
Another reason some people don't bring their own bag is because they think it's not a good idea to use the same bag for food waste and recyclable materials. But this also has a false assumption: that all plastic bags are the same and will eventually degrade into nothingness. In fact, most plastic bags don't get recycled because they contain markers which identify the material inside them. So there's no way to re-use them or recycle them into new products.
Finally, some people don't bring their own bag because they believe it's unfair that they should have to pay for another person's mistake. But this is a completely false premise.
It is projected that two billion plastic bags are used in New South Wales each year, with just 14 percent recycled. A plastic bag has an average usable life of 12 minutes before it is abandoned, either for landfill disposal (1.72 billion bags) or as litter. Quickly everywhere from beaches to national parks, all over the world, you will find evidence of our careless use of plastic.
Plastic bags are only used once and then discarded, often ending up in landfills or being littered into nature. They can take hundreds of years to decompose. Recycling plastic bags returns less than half of their original weight and requires energy and water to process them into new products. There are more efficient ways to package foods.
The global annual rate of plastic bag production is about 70 million tons, and even if recycling rates were 100 percent they would still be too many. The main source of pollution comes from incinerators that burn waste containing plastic bags along with other garbage such as paper and metal. These fires produce toxic gases such as dioxins which are known carcinogens.
Landfill sites also face contamination problems due to the number of bags that get dumped into single containers. This reduces the amount of space available for other items being disposed of at the same time, resulting in more items being thrown away and creating more room for more trash.