A walk around suburbia soon provides evidence of this problem. Common items of detritus lying around include discarded plastic bags, plastic water and soft drinks bottles and beverage tins, but we shall just consider waste plastics here. The older generation will remember that in former times the rubbish was largely paper and glass bottles. Paper would biodegrade and school children would return bottles to the shop to reclaim the deposit. Formerly too, people all had shopping bags and baskets which day after day they took with them to the shops.
Plastics are made by a high-energy process called polymerization. As a result they are chemically very stable and do not biodegrade. That they are then used for such ephemeral, short-life items as supermarket shopping bags represents a major misuse of valuable material, particularly as they are made from non-renewable oil.
Until recently given away free of charge they are not valued, and little thought is given to their disposal. Similarly, plastic water bottles are no-deposit (unlike the old glass bottles), and they are similarly disposed of in a careless way by consumers.
Why should we be concerned by this? Beside their durability, plastics are low-density materials, which mean that they blow around in the breeze and they float in water. Carelessly disposed of, they can find their way into streams and water-courses and end up in the sea. Picnickers on the beach can leave such waste behind them, and the next tide will carry it out to sea. We understand the working of the various ocean currents, and we know that regardless of the point of entry, floating waste can reach almost everywhere on our planet. Floating plastic accumulates in large gyres; there is one in the Pacific Ocean thought to contain up to 50 million tonnes of plastic waste.
Sea birds spot small pieces of floating plastic, mistake them for morsels of food and swallow them. Worse still, they feed them to their chicks who then become full and die of starvation. In 2010, a story broke telling of how thousands of Albatross chick carcases were found on Midway Island in the Pacific. Each of their decomposing bodies was filled with small pieces of plastic. More recently, environmental scientists carried out a post mortem on a dead whale and found that its digestive tract was blocked by plastic waste. So plastic is a toxic material that brings death to creatures large and small. The good news is that the recent imposition of a small charge for plastic bags has reduced the amount of waste found on beaches by a very large amount.
So, what can you do?
- Buy yourself a shopping bag or bags and take them with you. It is easy to keep a folded bag in your pocket for odd unexpected purchases.
- For drinking water, buy a re-fillable water bottle from the outdoor shop and use it.
- If you must buy bottled water, the bottle must be responsibly disposed of when empty by placing it in the recycling material bin.
This is important for two reasons. Firstly, we share our world with several million other species of life, and we each depend on many of these for our survival. Anything that reduces biodiversity reduces our ability to survive in the future. Secondly, it is now possible to recycle most plastic materials and to turn them into useful building products with long service lives. So recycling your plastic waste provides feedstock for the manufacture of many useful things, avoiding the need to extract more virgin material.
Hopefully, we shall return to the questions of biodiversity and recycling in future pieces.
If you have any thoughts or reflections, please contact us.
John Sturges : j.sturges@leedsbeckett.ac.uk;
Julia Hyliger Julia.hyliger@hotmail.co.uk;
February 2017