The Problem with Plastic

Plastic... a great invention or the worst invention? Versatile, strong and flexible are just some of the beneficial properties of plastic. With many household items now made from plastic instead of the traditional wood or metal, most people use plastic in some form on a daily basis. However the problems with its eventual disposal are rarely considered when plastic items are purchased. 

 

• Types of Plastic
• Environmental Impacts
• Recycling
• Alternatives to Plastic
• Plastic Bags

 

Types of Plastic

Plastic is identified by a number in a triangle and is sometimes acompanied by an abbreviation of the name of the type. There are 6 common types of plastic:

 

1. Polyethylene Terephthalate (PET or PETE) 

Commonly used for soft drink bottles and food packaging.  It can be clear or green (clear has a far higher market value). It's common name is 'Polyester' and it can be spun into fibres to make fleece and duvet material.

Recycled PET bottles are often spun into fibres rather than made into new plastic bottles. This is because plastic loses its quality when recycled and so it is preferable to make a product with a long life such as a fleece jacket rather than a product that will need recycling many times such as a bottle.

 

2. High Density Polyethylene (HDPE)

Commonly used for household liquids and chemicals e.g bleach, shampoo, washing up liquid. It has good chemical resistance and barrier properties and is strong making it suitable for holding chemicals.

Recycled HDPE is made into new bottles but is often made into durable items such as garden furniture, benches, fences, litter bins and pipes. This is because plastic loses its quality when recycled and so it is preferable to make a product with a long life such as a bench rather than a product that will need recycling many times such as a bottle. Durable products such as garden furniture also take advantage of the strength of HDPE.

 

3. Polyvinyl Chloride (PVC

Commonly used for packaging sheet, windows, wire and cable insulation, film and credit cards.

Recycled PVC is usually made into packaging, decking, garden hose, traffic cones.

 

4. Low Density Polyethylene (LDPE)

Commonly used for film e.g carrier bags, refuse bags and heat sealed non-rigid containers. It is highly flexible and yet strong.

Recycled LDPE is made into new film such as carrier bgs and refuse sacks.

 

5. Polypropylene (PP)

Commonly used for yogurt pots, margarine tubs and ice-cream tubs. It has good chemical resistance, is strong, and has a high melting point making it good for hot-fill liquids.

PP is not commonly recycled because of problems with food residues and also because it loses quality when recycled. In many cases,  it uses less energy and resources to make PP products from raw materials than from recycled PP and so very few reprocessors exist that recycle PP.

 

6. Polystyrene (PS)

Commonly used for CD cases, food packaging trays, foam egg cartons, vending cups, cutlery, plates and protective packaging.

Cups made from PS are recycled into rulers, pens, coasters and keyrings - specialist companies recycle PS cups from offices. Most PS is recycled in China where relatively low labour costs make it financially viable.

 

Environmental Impacts

The manufacture of plastics comprises 8% of the world's oil usage, producing harmful solid wastes such as carbon dioxide, nitrogen oxide and sulphur dioxide emissions.

Plastic degrades very slowly. Athough it is not known for sure, it is estimated that it would take many hundreds of years for a plastic bottle to disappear. That means that every plastic item ever made that has not been recycled still exists!

Plastic litter, in particular plastic bags, can be blown into trees and fields where they can accidentally be ingested by animals causing eventual death through suffocation or starvation. Plastic items can end up in the sea and be transported by the currents to places thousands of miles from where they originated. Uninhabited islands have been found to have vast amounts of plastic on their beaches that has travelled via the oceans currents from populated countries.

 

Recycling

Recycling plastic prevents the build of plastic waste in the environment. It reduces the amount of oil needed to make plastic products and in most cases requires less energy that the amount of energy needed to create plastic products from virgin oil. 1.8 tons of oil are saved for every ton of recycled plastic produced.

However, it is still an energy intensive process and encourages a single-use attitude towards packaging. Plastic bottles for drinks require energy intensive manufacture, transportation of bottle and contents to shop, transportation from household to recycling facility and energy-intensive recycling process to create new product. All this for one drink consumed in a matter of minutes or hours. In comparison, a sturdy drinks bottle used again and again can last for years.

The Process

1. Plastics are sorted according to type and colour

2. They are washed and chopped into pieces then sorted again using a floatation device to separate lids from bottles

3. The pieces are melted and then filtered to remove contaminates

4. The plastic is squeezed out into strands and chopped into pellets or spun into a fine fibre to make fleece

 

Alternatives to Plastic

Biopolymers

Also known as biodegradable plastics. There are four main categories:

Starch - A natural polymer that can be melted and reformed. It disintegrates in water which is advantageous for disposal but limits its packaging uses.

Sugar - These are derived from sucrose and undergo a process of bacterial fermentation. The bacteria grow plastic within their cells and this plastic is harvested. The high cost of this biopolymer has restricted its popularity.

Cellulose - Used to make cellophane. It is biodegradeable and can be composted. It is far more expensive than polymers such as PP however and so its use is decreasing.

Synthetic - Synthetic compunds can be used to make biodegradable plastic. However they are still based on petroleum and remain expensive.

Combinations of the four types above provide more options at cheaper prices.

Some Biopolymers can be composted in a home compost bin and are identified by this symbol.

Although it looks like plastic it is commonly derived from cornstarch and so will break down naturally. Keep it out of the recycling bag though as it cannot be recycled along with other plastic.

Natural Materials

Alternative materials such as paper, wood, metal, jute or hemp are bio-degradeable, easily recycled and can be produced and recycled on a local scale with minimal transportation needs. Many household products have plastic, metal and wood versions - everything from kitchen utensils to washing line pegs!  When purchasing products, try to choose a non plastic option - it will make it far easier to dispose of.

Tips for reducing plastic usage

• Plastic packaging can be avoided by purchasing food items such as fruit and veg loose and avoiding pre-prepared meals. Using raw ingredients means less packaging, healthier food and often costs less.
• Drink tap water not bottled water - take a reusable bottle with you when going out to save on buying plastic bottles of water.
• Buy products in refillable packaging
• Use refillable toner cartridges
• Take your own reusable bags with you when shopping - keep them handy in the car or workplace for spontaneous shopping trips

 

Plastic Bags

The average person uses 300 plastic carrier bags each year! Most are used for a matter of minutes before being discarded.

Some plastic bags are made from bioploymers and therefore are degradable under certain conditions. However these conditions are not found in the home compost bin and so these bags are not compostable. Neither are they recyclable and so they are destined for landfill where they are unlikely to break down as the sunlight required is not present. It is better to avoid plastic bags altogether and take a jute, cotton or hemp bag on each shopping trip.