Sudipta Ghosh
Deep in the Pacific Ocean, about 800 kms off the coast of California and 300 kms off the coast of Japan, is a stretch that could be one of the symbols of modern civilization. The Great Pacific Garbage Patch, as it has been named, estimated to be more than four times the size of India, is filled with trash consisting mostly of plastic debris. This enormous amount of plastic has been discarded on the land and then carried by wind, rainwater, through the drains to the rivers and streams and into the ocean. The ocean current has carried them at its whim to this patch in the Pacific Ocean.
Plastic, which had been hailed as a wonder material in the early 20th century, is increasingly becoming the face of all things going wrong with our civilization. This versatile material is unlike anything that is available in nature. It is durable, can be easily shaped, lightweight, waterproof and very cheap. New properties are getting added to it with every passing day resulting in new applications of plastic. But the same benefits of plastic have been the cause for its adverse impact on health and environment. Plastic does not decompose, hence almost every molecule of plastic produced so far is still somewhere in the environment and will continue to be so for hundreds of years. So one can still find almost every used and discarded plastic items somewhere on this earth. Let us try to understand the evolution of plastic starting from the need for such a material, what made it so popular, the problems, how to address the problems and steps that we can take up immediately.
What is plastic after all?
The term ‘plastic’, first used in the trade journal Plastics in 1925, comes from the Greek word plastikos, which means “capable of being shaped or moulded” and plastos meaning “moulded”. Plastics are polymers made of long chains of atoms or small molecules, bonded in a repeating pattern. All plastics are polymers but not all polymers are plastics. Plastic is mainly composed of carbon and hydrogen bonded with other elements like oxygen, nitrogen, chlorine and fluorine. The amount and the arrangement of the elements produce the different varieties of plastics. The human quest for materials that can be easily moulded or shaped and hardened into a final manufactured form has led to the use of natural plastics like horns, ivory, rubber, and shellac. But these natural resources could not keep pace with the rising demand and gave way to synthetically produced plastic from crude oil, coal or natural gas. Most of the plastics used today are synthetic plastics.
History of plastic
The first synthetic plastic, called Parkesine, was made by Alexander Parkes in 1862 from organic cellulose. The effort to mass produce this plastic failed because of poor quality. An early plastic that succeeded on a large scale is Celluloid, meaning “like cellulose”. John Wesley Hyatt synthesized celluloid from cotton fibre and camphor in 1869, apparently to make a cheaper substitute for ivory billiard balls. Celluloid went on to have a much bigger impact by replacing scarce and expensive natural materials and gave access to a host of goods. Perhaps the greatest impact of Celluloid was serving as the base for photographic films. But extensive use of Celluloid was limited due to its tendency to catch fire easily during production and the need for a labour intensive process.
The first completely synthetic plastic, which did not use cellulose from plant sources, was invented by Leo Baekeland in 1907. Baekeland was looking for a material to replace shellac as an electrical insulator. It was named Bakelite and was made from an extract of coal tar. Bakelite was used for making clocks, radios, phones, etc., that were uniquely styled. Each subsequent decade saw the introduction of new and more versatile plastics like Polyvinyl Chloride (PVC), Polyethylene, Nylon, Polystyrene, Polyethylene Terephthalate (PET) and so on. The production of plastic increased rapidly to meet the huge demand during World War II. After the war, this huge capacity was suddenly available for the general public in the form of cheap consumer goods and textiles.
Types of plastics
Plastic is the generic name given to a wide variety of polymers. Plastics can be broadly classified into Thermoset plastics and Thermoplastics. Thermoset plastics like Bakelite are the ones that can be melted and moulded only once. Once it solidifies it cannot be re-melted. Thermoplastics, on the other hand, can be re-melted and remoulded. This quality makes Thermoplastics recyclable. Most of the plastics used today are Thermoplastics.
Plastics get their names and properties based on the composition of the polymer it is made of. The polymer type can be identified from the Resin Identification code placed on plastics. The easy way to check for the code is to look for the number inside a rounded triangle at the bottom of a plastic container. For example, most water bottles are made from PET plastic and have a resin code 1 at the bottom. The most commonly used plastic is Polyethene, which is used in plastic bags, toys, shampoo bottles, etc.
Why is plastic popular?
Plastic has an overwhelming impact on the way we live. Many plastics have become household names like Nylon, Polyester, Polyethene and Teflon. Plastic has become popular because it is versatile and very cheap.
Plastics are artificially made and almost any combination of properties can be incorporated to accommodate a wide variety of applications. We have plastics that are strong, lightweight, transparent, impermeable, inert, and insulating (heat or electricity). These properties have made plastic a versatile material. It is extensively used in packaging, house construction, health care, electrical, electronics, agriculture, sports, and textiles. Today, plastics are replacing almost all traditional materials like jute, cotton, leather, paper, and rubber.
Most plastics are made from petrochemicals, essentially oil and natural gas, which are cheap today. The plastic industry is highly mechanised and less labour intensive. All this makes plastic very cheap.
Problems with plastic
The wonder material plastic has many problems related to the poisonous effects (called toxicity) and environmental hazards.
Poisonous effects:
Pure plastic is insoluble in water and is relatively chemically inert. So plastics have low toxicity in their pure form. However, plastics are rarely used in their pure form. A variety of poisonous additives are added to it to get the desired property. Traces of these chemicals can leach out of the plastic when it comes in contact with food, water, etc. The chemicals that are used in PVC to make them flexible have been found to interfere with hormonal functions and are suspected to cause cancer. Polycarbonate, used to make transparent baby bottles has Bisphenol A (BPA), which is a known hormone disruptor and can lead to cancer, insulin resistance, inflammation, and heart disease. Some of the additives are suspected to cause genetic damages also.
With more and more use of plastic in our daily life, the toxic risk is rising. In a country like India, cheap plastics have increased accessibility, especially for the poor, but at the same time improper use has exposed them to major health hazards. The lack of awareness and a proper plastic disposal mechanism sometimes leads to burning of plastic along with other garbage. When plastics are burnt, poisonous substances like carbon monoxide, dioxin, and furan are released into the air. Dioxin and furans have been linked to cancer and respiratory problems and can be fatal.
Environmental hazards:
Environmentally, plastic is a growing disaster. Most synthetic plastics are made from fossil fuels using energy intensive techniques. It is estimated that 8% of the global crude oil is used for plastic production. The manufacturing of plastic creates and releases large quantities of chemical pollutants.
Global plastic consumption is around 200 million tons and is growing at 5% annually. Globally, more than 500 billion plastic bags are consumed each year most of which end up in landfills. They clog the drainage and sewerage systems, which results in severe water logging and flooding in the cities.
Plastics do not decompose and are resistant to the natural process of disintegration and hence they will remain in the environment for hundreds or thousands of years. And even when they disintegrate, they release many toxic chemicals which contaminate the land, lakes, rivers, and percolates to the underground water.
At least 267 different marine species have known to have suffered from entanglement or ingestion of plastic debris. Plastics have also been found in the guts of animals like goat, cows, and deer and have been responsible for their deaths.
Plastics disintegrate into minute particles out of wear and tear in moving water, wind, and exposure to sun. These minute particles get mixed up with planktons and other small organisms and consumed by bigger organisms. Plastic is slowly but surely entering the food chain and the consequences can be serious and far-reaching.
How to address the problems
The first thing we could do is to reduce the indiscriminate use of plastic. There is a serious need to rationalize the use of plastic. There are some specific areas where plastic has really been useful. For example, in modern health care, plastic is used to make disposable syringes, catheters, artificial cornea, hearing aids and capsule coatings, which are hard to replace with cheap and equally effective substitutes. But there is a huge scope to reduce the usage of plastic in most areas.
The packaging industry, which accounts for 35% of the global plastic consumption is one such application which can be greatly rationalized. There is an enormous amount of plastic used in retail packaging like shampoo sachets, packets of rice, pulses, biscuits, and other commodities. This is mostly unnecessary and should be completely avoided. There is a need to re-invent traditional packing materials like jute, paper, cotton, etc.
A lot of research is going on to develop bio-degradable plastic from plant extracts. There are some varieties of bio-degradable plastic already available in the market. Bio-degradable plastic has good potential to become a viable alternative, though currently they are costlier than synthetic plastic.
Recycling plastic is one of the potential solutions to prevent releasing plastic garbage in the environment. Currently, the amount of plastic recycled could be as low as 10% of the total plastic disposed annually. New plastic will become costly with the rising price of petrochemicals and hence recycling will play a bigger role in future.
The low recycling rate is due to the complexity of sorting and processing. The additives in plastics and the way they are combined with other material renders them non-recyclable. For example, tetrapak, used for packaging beverage, milk, and oil, uses paperboard layered with thin polyethene that makes it largely non-recyclable. Moreover, typically a plastic is not recycled into the same type of plastic, e.g. soft drinks bottles could be recycled to plastic chairs. And even worse, the products made from recycled plastic are often not recyclable.
Perhaps the most important alternative is a change in lifestyle. We have to consume less and consume prudently. Our commodities have to travel less distance. We need to consume more of seasonal food, produced locally that needs less packaging. The need for clothing and consumer goods should be guided by necessity rather than by the artificial urge created by advertisements.
The world average per capita plastic consumption is 26 kg. There is a direct linkage of per capita plastic usage with the per capita Gross National Income. The more prosperous countries tend to use more plastic. The per capita consumption for North America is 90 kg, Western Europe 65 kg, China 12 kg and India 5 kg. But the bad news is India’s consumption is growing rapidly at 15% and likely to become 10 kg by 2012. So we have look for less use, re-use and recycle whatever is used.
Let us start today
We can do our bit at the individual level to develop a prudent ‘plastic behaviour’.
We could start with building awareness of the amount and extent of plastic used in our daily life. Look around the classroom, school, and home to identify the items made of plastic. How many of them come in direct contact with the food you eat or the water you drink? What did you do with the wrapper of the last biscuit packet you opened? How many plastic bags did your family use in the last month? How many bottles of water did you buy in your last railway/bus trip? What did you do with the empty bottles? What is the material of the mattress on which you sleep? What is the material of the dress you are wearing? Did you use any plastic container to heat food?
Put a plastic bag and a piece of newspaper in separate pots under a layer of soil and water them daily. What happens to the plastic bag and piece of paper after a month?
Plastic carry bags are one of the major challenges of urban waste management. Their use is mostly unnecessary and could be avoided to a large extent. There is a ban on plastic bags below a thickness of 40 microns in Hyderabad. Plastic bags below 40 microns are not recyclable and choke the storm water drains resulting in water logging and flooding. Plastic bags over 40 microns are recyclable but their usage should be minimized. We can reduce the use of plastic bags by carrying cloth/paper bags for our groceries and vegetables.
Avoid having packaged beverages and drinking water. Ready-to-eat food items need more plastic packaging and could be avoided. Try to go for clothes made out of natural fibres like cotton, silk instead of synthetic fibres. Say no to use-and-throw plastic/styrofoam cups, glasses, plates in functions, festivals, trains, etc. Don’t litter plastic cups, bags, bottles, ice-cream cups and biscuit/snack/chocolate wrappers at any public places.
Plastic tips
In a world where we are surrounded by plastic the best we can do is to reduce the use and exposure to plastic.
Here are some tips:
- Buy fresh fruits, vegetables, and poultry so that they need not be stored in plastic wrappings. Store them in steel or glass containers if required.
- Always carry a cloth or reusable plastic bags when going out of the house for any planned or unplanned buying.
- Line the garbage bin with newspaper instead of plastic bags for daily use.
- Always look to reuse. For example, the plastic box used for packing sweets can be washed and carried back to the shop for subsequent buying.
- Never heat food in plastic containers even if the containers are marked safe for heating. Avoid having hot beverages, milk in plastic containers.
- Avoid storing food items like pickle, oil, juices, and sweets in plastic containers for a long time.
- Use clothes, mattresses, shoes made out of natural materials like cotton, jute, and leather.
Plastic is a serious threat to the environment and has adverse impacts on our health. There is an urgent need to work towards a plastic-free world. Conscious rationalization of usage can bring down the consumption by 10-30% immediately. Strong political will and change in lifestyle can drastically cut the usage in the long run. Let us start with the awareness that most plastic usage is unnecessary and develop a better individual plastic habit for a better tomorrow.
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References
http://www.npr.org/templates/story/story.php?storyId=114331762
http://www.scientificamerican.com/article.cfm?id=a-brief-history-of-plastic-world-conquest&offset=6
http://www.care2.com/greenliving/safe-plastics-for-lunchboxes.html
http://lifelessplastic.blogspot.com/2010/06/toxic-america-im-on-cnn-homepage.html
http://www.ntnu.no/gemini/2001-06E/28-33.htm
http://www.telegraph.co.uk/earth/environment/5208645/Drowning-in-plastic-The-Great-Pacific-Garbage-Patch-is-twice-the-size-of-France.html
http://www.guardian.co.uk/environment/2008/feb/23/plasticbags.waste
http://cipet.gov.in/plastics_statics.html
He can be reached at ghosh.sudipta@wipro.com.