Plastic pollution From Wikipedia, the free encyclopedia

Plastic waste at Coco Beach in India.

Plastic pollution involves the accumulation of plastic products in the environment that adversely

affects wildlife, wildlife habitat, or humans.[1] Many types and forms of plastic pollution exist. Plastic pollution can adversely affect lands, waterways and oceans. Plastic reduction efforts have occurred in some areas in attempts to reduce plastic consumption and promoteplastic recycling. The prominence of plastic pollution is correlated with plastics being inexpensive and durable, which lends to high levels of plastics used by humans. [2]

Contents

[hide]

1 Types

2 Effects on the environment

o 2.1 Land

o 2.2 Ocean

o 2.3 Effects on animals

3 Effects on humans

4 Reduction efforts

o 4.1 Collection

5 See also

6 References

7 Bibliography

8 Further reading

9 External links

Types[edit]

Plastic pollution in urban area

Plastic pollution occurs in many forms, including but not limited to littering, marine debris (man-made waste that has been released in a lake, sea, ocean, or waterway), plastic particle water pollution, plastic netting and Friendly Floatees. A large percentage of plastic produced each year is used to make single-use, disposable packaging items or products which will get permanently thrown out

within one year.[3] Often, consumers of the various types of plastics mainly use them for one purpose and then discard or recycle them.

As per the United States Environmental Protection Agency, in 2011 plastics constituted over 12% of municipal solid waste.[4] In the 1960s, plastics constituted less than 1% of municipal solid waste. [4]

Effects on the environment[edit] Land[edit]

Chlorinated plastic can release harmful chemicals into the surrounding soil, which can then seep into groundwater or other surrounding water sources. [5] This can cause serious harm to the species that drink this water.

Landfill areas are constantly piled high with many different types of plastics. In these landfills, there are many microorganisms which speed up the biodegradation of plastics. Regarding biodegradable plastics, as they are broken down, methane is released, which is a very powerful greenhouse

gas that contributes significantly to global warming.[6]

Ocean[edit]

Nurdles are plastic pellets (a type of microplastic) that are shipped in this form, often in cargo ships, to be used for the creation of plastic products. [7] A significant amount of nurdles are spilled into oceans, and it has been estimated that globally, around 10% of beach litter is nurdles. [7] Plastics in oceans typically degrade within a year, but not entirely, and in the process toxic chemicals such as bisphenol A and polystyrene can leach into waters from some plastics. [8] Polystyrene pieces and nurdles are the most common types of plastic pollution in oceans, and combined with plastic bag s and food containers make up the majority of oceanic debris. [9] In 2012, it was estimated that there

was approximately 165 million tons of plastic pollution in the wor ld's oceans.[8]

Effects on animals[edit]

Plastic pollution has the potential to poison animals, which can then adversely affect human food supplies.[10][11] Plastic pollution has been described as being highly detrimental to large marine mammals, described in the book Introduction to Marine Biology as posing the "single greatest threat" to them.[12] Some marine species, such as sea turtles, have been found to contain large proportions of plastics in their stomach.[10] When this occurs, the animal typically starves, because the plastic blocks the animal's digestive tract.[10]Marine mammals sometimes become entangled in plastic products such as nets, which can harm or kill them. [10]

Over 260 species, including invertebrates, have been reported to have either ingested plastic or become entangled in the plastic. When a species gets entangled, its movement is seriously reduced, therefore making it very difficult to find food. Being entangled usually results in death or severe lacerations and ulcers.[13] It has been estimated that over 400,000 marine mammals perish annually due to plastic pollution in oceans.[10] In 2004, it was estimated that seagulls in the North Sea had an average of thirty pieces of plastic in their stomachs. [14]

Effects on humans[edit]

Plastics contain junk of many different types of chemicals, depending on the type of plastic. The addition of chemicals is the main reason why these plastics have become so multipurpose, however

this has problems associated with it. Some of the chemicals used in plastic production have the potential to be absorbed by human beings through skin absorption. [15] A lot is unknown on how severely humans are physically affected by these chemicals. Some of the chemicals used in plastic production can cause dermatitis upon contact with human skin.[15] In many plastics, these toxic chemicals are only used in trace amounts, but significant testing is often required to ensure that the toxic elements are contained within the plastic by inert material or polymer. [15]

Plastic pollution can also affect humans in which it may create an eyesore that interferes with enjoyment of the natural environment.[16] may be a cause of diseases in humans.

Reduction efforts[edit]

Household items made of various types of plastic.

Efforts to reduce the use of plastics and to promote plastic recycling have occurred. Some supermarkets charge their customers for plastic bags, and in some places more efficient reusable or biodegradable materials are being used in place of plastics. Some communities and businesses have put a ban on some commonly used plastic items, such as bottled water and plastic bags. [17]

Collection[edit]

The two common forms of waste collection include curbside collection and the use of drop -off recycling centers . About 87 percent of the population in the U.S.A. (273 million people) have access to curbside and drop-off recycling centers. In curbside collection, which is available to about 63 percent of the U.S.A. population (193 million people), people place designated plastics in a special bin to be picked up by a public or private hauling company. [18] Most curbside programs collect more than one type of plastic resin; usually both PETE and HDPE. [19] At drop-off recycling centers, which are available to 68 percent of the U.S.A. population (213 million people), people take their recyclables to a centrally located facility.[18] Once collected, the plastics are delivered to a material recovery facility (MRF) or handler for sorting into single-resin streams to increase product value. The sorted plastics are then baled to reduce shipping costs to reclaimers. [19]

There are varying rates of recycling per [60mps in hongkong] type of plastic, and in 2011, the overall plastic recycling rate was approximately 8% in the United States. [4]Approximately 2.7 million tons of plastics were recycled in the U.S. in 2011. [4] Some plastics are recycled more than others; in 2011 "29 percent of HDPE bottles and 29 percent of PET bottles and jars were recycled." [4]

References[edit]

1. Jump up^ "Plastic pollution". Encyclopaedia Britannica. Retrieved 1 August 2013.

2. Jump up^ Hester, Ronald E.; Harrison, R. M. (editors) (2011). Marine Pollution and

Human Health. Royal Society of Chemistry. pp. 84-85. ISBN 184973240X

3. Jump up^ Hopewell, 2009[page needed]

4. ̂ Jump up to:a b c d e "Plastics". Epa.gov. Retrieved 3 September 2012.

5. Jump up^ Aggarwal,Poonam; (et al.) Interactive Environmental Educatiaon Book VIII. Pitambar Publishing. p. 86. ISBN 8120913736

Bibliography[edit]

Derraik, José G.B (2002). "The pollution of the marine environment by plastic debris: A review". Marine Pollution Bulletin 44 (9): 842–52. doi:10.1016/S0025-326X(02)00220-5. PMID 12405208.

Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward (2009). "Plastics recycling: Challenges and

opportunities". Philosophical Transactions of the Royal Society B: Biological Sciences 364 (1526): 2115–26. doi:10.1098/rstb.2008.0311. PMC 2873020. PMID 19528059.

Knight, Geof (2012). Plastic Pollution. Capstone. ISBN 978-1-4329-6039-1

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------------------------------------------------------------------------------Environmental effects

See also: Plastic pollution, Marine debris and Great Pacific Garbage Patch

Most plastics are durable and degrade very slowly; the very chemical bonds that make

them so durable tend to make them resistant to most natural processes of degradation.

However, microbial species and communities capable of degrading plastics are

discovered from time to time, and some show promise as being useful for

bioremediating certain classes of plastic waste.

In 1975 a team of Japanese scientists studying ponds containing waste water from

a nylon factory, discovered a strain of Flavobacterium that digested certain

byproducts ofnylon 6 manufacture, such as the linear dimer of 6-

aminohexanoate.[34] Nylon 4 or polybutyrolactam can be degraded by the (ND-10

and ND-11) strands of Pseudomonas sp. found in sludge. This produced γ-

aminobutyric acid (GABA) as a byproduct.[35]

Several species of soil fungi can consume polyurethane.[36] This includes two

species of the Ecuadorian fungus Pestalotiopsis that can consume polyurethane

aerobically and also in anaerobic conditions such as those at the bottom of

landfills.[37]

Methanogenic consortia degrade styrene, using it as a carbon

source.[38] Pseudomonas putida can convert styrene oil into

various biodegradablepolyhydroxyalkanoates.[39][40][41]

Microbial communities isolated from soil samples mixed with starch have been

shown to capable of degrading polypropylene.[42]

The fungus Aspergillus fumigatus effectively degrades plasticized

PVC.[43] Phanerochaete chrysosporium was grown on PVC in a mineral salt

agar.[44] Phanerochaete chrysosporium, Lentinus tigrinus, Aspergillus niger,

and Aspergillus sydowii can also effectively degrade PVC.[45] Phanerochaete

chrysosporium was grown on PVC in a mineral salt agar.[44]

Acinetobacter has been found to partially degrade low molecular

weight polyethylene oligomers.[46] When used in combination, Pseudomonas

fluorescens and Sphingomonascan degrade over 40% of the weight of plastic bags

in less than three months.[47][48] The thermophilic bacterium Brevibaccillus

borstelensis (strain 707) was isolated from a soil sample and found capable of using

low-density polyethylene as a sole carbon source when incubated at 50 degrees

Celsius. Pre-exposure of the plastic to ultravioletradiation broke chemical bonds and

aided biodegradation; the longer the period of UV exposure, the greater the

promotion of the degradation.[49]

Less desirably, hazardous molds have been found aboard space stations, molds

that degrade rubber into a digestible form.[50]

Several species of yeasts, bacteria, algae and lichens have been found growing on

synthetic polymer artifacts in museums and at archaeological sites.[51]

In the plastic-polluted waters of the Sargasso sea, bacteria have been found that

consume various types of plastic; however it is unknown to what extent these

bacteria effectively clean up poisons rather than simply releasing them into the

marine microbial ecosystem.

Plastic eating microbes also have been found in landfills.[52]

Nocardia can degrade PET with an esterase enzyme.[53]

The fungi Geotrichum candidum, found in Belize, has been found to consume

the polycarbonate plastic found in CD's.[54][55]

Phenol-formaldehyde, commonly known as bakelite, is degraded by the white rot

fungus Phanerochaete chrysosporium [56]

The futuro house was made of fibreglass-reinforced polyesters, polyester-

polyurethane, and poly(methylmethacrylate.) One such house was found to be

harmfully degraded by Cyanobacteria and Archaea.[57][58]

Since the 1950s, one billion tons of plastic have been discarded and some of that

material might persist for centuries or much longer, as is demonstrated by the

persistence of natural materials such as amber.[59]

Serious environmental threats from plastic have been suggested in the light of the

increasing presence of microplastics in the marine food chain along with many highly

toxic chemical pollutants that accumulate in plastics. They also accumulate in larger

fragmented pieces of plastic called nurdles.[60] In the 1960s the latter were observed in

the guts of seabirds, and since then have been found in increasing concentration.[61] In

2009, it was estimated that 10% of modern waste was plastics,[9] although estimates

vary according to region.[61] Meanwhile, 50-80% of debris in marine areas is plastic.[61]

Before the ban on the use of CFCs in extrusion of polystyrene (and in general use,

except in life-critical fire suppression systems; see Montreal Protocol), the production of

polystyrene contributed to the depletion of the ozone layer, but current extrusion

processes use non-CFCs.

Climate change

The effect of plastics on global warming is mixed. Plastics are generally made from

petroleum. If the plastic is incinerated, it increases carbon emissions; if it is placed in a

landfill, it becomes a carbon sink[62] although biodegradable plastics have caused

methane emissions.[63] Due to the lightness of plastic versus glass or metal, plastic may

reduce energy consumption. For example, packaging beverages in PET plastic rather

than glass or metal is estimated to save 52% in transportation energy.[3]

Production of plastics

Production of plastics from crude oil requires 62 to 108 MJ of energy per kilogram

(taking into account the average efficiency of US utility stations of 35%). Producing

silicon and semiconductors for modern electronic equipment is even more energy

consuming: 230 to 235 MJ per 1 kilogram of silicon, and about 3,000 MJ per kilogram of

semiconductors.[64]This is much higher, compared to many other materials, e.g.

production of iron from iron ore requires 20-25 MJ of energy, glass (from sand, etc.) -

18-35 MJ, steel (from iron) - 20-50 MJ, paper (from timber) - 25-50 MJ per kilogram.[65]

Incineration of plastics

Controlled high-temperature incineration, above 850C for two seconds,[66] performed

with selective additional heating, breaks down toxic dioxins and furans from burning

plastic, and is widely used in municipal solid waste incineration.[66] Municipal solid waste

incinerators also normally include flue gas treatments to reduce pollutants

further.[66] This is needed because uncontrolled incineration of plastic produces

polychlorinated dibenzo-p-dioxins, a carcinogen (cancer causing chemical). The

problem occurs as the heat content of the waste stream varies.[67] Open-air burning of

plastic occurs at lower temperatures, and normally releases such toxic fumes.

Pyrolytic disposal

Plastics can be pyrolyzed into hydrocarbon fuels, since plastics have hydrogen and

carbon. One kilogram of waste plastic produces roughly a liter of hydrocarbon.[68]

Recycling

Thermoplastics can be remelted and reused, and thermoset plastics can be ground up

and used as filler, although the purity of the material tends to degrade with each reuse

cycle. There are methods by which plastics can be broken back down to a feedstock

state.

The greatest challenge to the recycling of plastics is the difficulty of automating the

sorting of plastic wastes, making it labor-intensive. Typically, workers sort the plastic by

looking at the resin identification code, although common containers like soda bottles

can be sorted from memory. Typically, the caps for PETE bottles are made from a

different kind of plastic which is not recyclable, which presents additional problems to

the automated sorting process. Other recyclable materials such as metals are easier to

process mechanically. However, new processes of mechanical sorting are being

developed to increase capacity and efficiency of plastic recycling.

While containers are usually made from a single type and color of plastic, making them

relatively easy to be sorted, a consumer product like a cellular phone may have many

small parts consisting of over a dozen different types and colors of plastics. In such

cases, the resources it would take to separate the plastics far exceed their value and

the item is discarded. However, developments are taking place in the field of active

disassembly, which may result in more consumer product components being re-used or

recycled. Recycling certain types of plastics can be unprofitable, as well. For example,

polystyrene is rarely recycled because it is usually not cost effective. These unrecycled

wastes are typically disposed of in landfills, incinerated or used to produce electricity

at waste-to-energy plants.

History

Plastic (LDPE) bowl, by GEECO, Made in England, c1950.

The development of plastics has evolved from the use of natural plastic materials

(e.g., chewing gum, shellac) to the use of chemically modified, natural materials

(e.g., rubber, nitrocellulose, collagen, galalite) and finally to completely synthetic

molecules (e.g., bakelite,epoxy, Polyvinyl chloride). Early plastics were bio-derived

materials such as egg and blood proteins, which are organic polymers. In 1600

BC, Mesoamericans used natural rubber for balls, bands, and figurines.[3] Treated cattle

horns were used as windows for lanterns in theMiddle Ages. Materials that mimicked

the properties of horns were developed by treating milk-proteins (casein) with lye.

In the 1800s, as industrial chemistry developed during the Industrial Revolution, many

materials were reported. In the 1800s, the development of plastics accelerated

with Charles Goodyear's discovery of vulcanization to thermoset materials derived from

natural rubber.

Parkesine is considered the first man-made plastic. The plastic material was patented

by Alexander Parkes, In Birmingham, UK in 1856.[6] It was unveiled at the 1862 Great

International Exhibition in London.[7] Parkesine won a bronze medal at the 1862 World's

fair in London. Parkesine was made from cellulose (the major component of plant cell

walls) treated with nitric acid as a solvent. The output of the process (commonly known

as cellulose nitrate or pyroxilin) could be dissolved in alcohol and hardened into a

transparent and elastic material that could be molded when heated.[8] By incorporating

pigments into the product, it could be made to resemble ivory.

In the early 1900s, Bakelite, the first fully synthetic thermoset, was reported by Belgian

chemist Leo Baekeland.

After World War I, improvements in chemical technology led to an explosion in new

forms of plastics, with mass production beginning in the 1940s and 1950s

(around World War II).[9] Among the earliest examples in the wave of new polymers

were polystyrene (PS), first produced by BASF in the 1930s,[3] and polyvinyl

chloride (PVC), first created in 1872 but commercially produced in the late 1920s.[3] In

1923, Durite Plastics Inc. was the first manufacturer of phenol-furfural resins.[10] In

1933, polyethylene was discovered byImperial Chemical Industries (ICI) researchers

Reginald Gibson and Eric Fawcett.[3]

In 1954, Polypropylene was found by Giulio Natta and began to be manufactured in

1957.[3]

In 1954, expanded polystyrene (used for building insulation, packaging, and cups) was

invented by Dow Chemical.[3]

Polyethylene terephthalate (PET)'s discovery is credited to employees of the Calico

Printers' Association in the UK in 1941; it was licensed to DuPont for the USA and ICI

otherwise, and as one of the few plastics appropriate as a replacement for glass in

many circumstances, resulting in widespread use for bottles in Europe.[3]

Special purpose plastics

See also: High performance plastics

Maleimide/Bismaleimide Used in high temperature composite materials.

Melamine formaldehyde (MF) – One of the aminoplasts, and used as a multi-

colorable alternative to phenolics, for instance in moldings (e.g., break-resistance

alternatives to ceramic cups, plates and bowls for children) and the decorated top

surface layer of the paper laminates (e.g., Formica).

Plastarch material – Biodegradable and heat resistant, thermoplastic composed

of modified corn starch.

Phenolics (PF) or (phenol formaldehydes) – High modulus, relatively heat resistant,

and excellent fire resistant polymer. Used for insulating parts in electrical fixtures,

paper laminated products (e.g., Formica), thermally insulation foams. It is a

thermosetting plastic, with the familiar trade name Bakelite, that can be molded by

heat and pressure when mixed with a filler-like wood flour or can be cast in its

unfilled liquid form or cast as foam (e.g., Oasis). Problems include the probability of

moldings naturally being dark colors (red, green, brown), and as thermoset it is

difficult to recycle.

Polyepoxide (Epoxy) Used as an adhesive, potting agent for electrical components,

and matrix for composite materials with hardeners including amine, amide,

and Boron Trifluoride.

Polyetheretherketone (PEEK) – Strong, chemical- and heat-resistant

thermoplastic, biocompatibility allows for use in medical implant applications,

aerospace moldings. One of the most expensive commercial polymers.

Polyetherimide (PEI) (Ultem) – A high temperature, chemically stable polymer that

does not crystallize.

Polyimide—A High temperature plastic used in materials such as Kapton tape.

Common plastics and uses

A chair made with a polypropylene seat

Polyester (PES) – Fibers, textiles.

Polyethylene terephthalate (PET) – Carbonated drinks bottles, peanut butter jars,

plastic film, microwavable packaging.

Polyethylene (PE) – Wide range of inexpensive uses including supermarket bags,

plastic bottles.

High-density polyethylene (HDPE) – Detergent bottles, milk jugs, and molded plastic

cases.

Polyvinyl chloride (PVC) – Plumbing pipes and guttering, shower curtains, window

frames, flooring.

Polyvinylidene chloride (PVDC) (Saran) – Food packaging.

Low-density polyethylene (LDPE) – Outdoor furniture, siding, floor tiles, shower

curtains, clamshell packaging.

Polypropylene (PP) – Bottle caps, drinking straws, yogurt containers, appliances,

car fenders (bumpers), plastic pressure pipe systems.

Polystyrene (PS) – Packaging foam/"peanuts", food containers, plastic tableware,

disposable cups, plates, cutlery, CD and cassette boxes.

High impact polystyrene (HIPS) -: Refrigerator liners, food packaging, vending cups.

Polyamides (PA) (Nylons) – Fibers, toothbrush bristles, tubing, fishing line, low

strength machine parts: under-the-hood car engine parts or gun frames.

Plastic Bags Pollution – Effects and Solutions

Plastic bags are among the items that are non-biodegradable. This

means that they are not biodegraded or, in simpler terms, do not decay.

Do you know that it takes thousands of years before one plastic bag can

turn into small particles? Yes, that’s how long for plastic bags to vanish

from our planet, Earth.

Image Source : pandora_6666

When they are thrown to garbage cans, plastic bags do not simply decay

unlike biodegradable ones like paper and leftovers. Try doing that and

observe for many days to see what the plastic becomes afterwards. If

they are scattered anywhere on the ground, they become the sources of

water pollution. It is possible that they will eventually end up in

waterways. If that happens, it can cause blockage to holes and give a

much inconvenient situation to the society. Have you seen some water

with plastics floating on it? That’s because of the wrong doings of people

when they do not properly throw plastic bags. Well, there are many

negative impacts that can cause by plastic bags. That’s what you are

going to learn as you continue to read.

What should people like you need to do in order to avoid having plastic

bags pollution? This is an important question when you read something

about plastic bags pollution. You must not only get information to be

aware of the effects of plastic bags. It is also very vital to know and apply

solutions to limit the rapid growth of plastic bags pollution. Plus, the

way to solve this kind of problem always begins with you. Do not expect

the government, environment organization or charities to do that. It has

to start with you, in your family, at home and everywhere you go. That is

one small way you can make which can turn into a big difference.

What Makes Plastic Bags Harmful to the Environment?

Plastic bags are made of various chemicals which are mainly toxic. That

is certainly very harmful to the health and the environment. The

chemicals used to make plastic bags are xylene, ethylene oxide and

benzene. These are toxic chemicals that are sources of various diseases

as well as disorders in humans. They do not only provide negative

effects on the health of people and animals but also to the air. These

chemicals can pollute the air too which again harm the living organisms.

They will not only affect humans and animals but also plants, water and

air.

How Plastic Bags Cause Danger to the Health and

Environment?

There are various ways on how plastic bags can harm the health of

humans and the entire environment. Two major methods that release

toxic chemicals of plastic bags are by burning and throwing. Whether

you burn or throw plastic bags, all the chemicals are released which can

cause harm to the society.

Image Source : velkr0

Some countries in the world do not throw plastic bags the right way.

Instead of putting in the non-biodegradable can, people tend to throw

them in the biodegradable or anywhere on the ground. This is one

mistake most people do these days. Even the smallest plastic bag like the

cover of candy has to be thrown properly. Others also try to burn them

and this is not also helpful as it poses a great threat in the air and soil. . I

did some of these mistakes before but I have opened my eyes and see the

effects of it. Now, I do not want that to happen that’s why I’m sharing

this.

When the chemicals are exposed, humans can inhale them which cause

problems in the respiratory. If they are thrown on grounds, animals and

birds may mistakenly think they’re foods causing poison after

consumption. When plastic bags are dumped in water, sea creatures and

fish won’t live longer. The entire marine life is also harmed.

Which Ways Help Resolve Plastic Bags Pollution?

It takes self-discipline to solve water pollution, air pollution and soil

pollution caused by plastic bags. The answer is not solely about

government campaigns or organizations. It starts within yourself aright

at your own backyard and inside house. Here are very simple and

effortless things you can do to help resolve plastic bags pollution.

1. Ban the Use of Plastic Bags

If possible, do not use any plastic bags anymore. It may be difficult to do

that because plastic bags are normally easy and light to carry. If only you

can limit your use until you are able to 100% stay away from it, then you

are helping the advocacy against plastic bags pollution.

2. Use Eco-Friendly or Biodegradable Bags

You do not have to worry about banning plastic bags. There are

environmentally friendly bags that you can use as an alternative. When

you go out to the grocery store or super market to buy things, have eco

friendly bags with you. That way you can say no to the use of plastic bags

even if the stores offer plastic bags. In fact, there are now new plastic

bags that are biodegradable. They can also be good options to use

without having to worry about pollution.

3. Reuse Plastic Bags

It is also possible to recycle the use of plastic bags. Instead of throwing

them, have them usable for your next usage. It helps you to reduce

getting more plastic bags in this case too. This is actually the first start

on how you can totally ban the use of plastic bags. If you think your

plastic bags have been reused for many times, then that’s the time you

can throw in the non-biodegradable can.

4. Donate Plastic Bags to Recycling Centers

From stores to industrial companies, there are places where you can give

your plastic bags for recycling. You can even find in your place some

recycling centers where you can donate the plastic bags you have.

Instead of throwing them away, just give them to these places to help

prevent pollution.

5. Do Not Throw Plastic Bags

Another easy way to avoid water and air pollutions is to avoid throwing

plastic bags. You can just reuse or donate them to recycling centers. It is

also a good approach to throw them at the right garbage can, which

must be in a non-biodegradable can.

As plastic bags won’t be easy to stop in giving threats to humans and

pollutions in the environment, doing your own way to help prevent it

from being worse is not difficult either. Just do the right things that you

think can contribute in the reduction of air, water and soil pollution

caused by plastic bags. Remember that changes in the environment have

to start within and from you before you expect others to do the same. Plastic wastes – Reduce, Reuse and Recycle of plastics are essential to make

environment greener and safer:

1. Introduction - We find considerable growth in use of plastic everywhere due to

various beneficial properties of plastics, such as:

(a) Extreme versatility and ability to be tailored to meet very specific technical

needs.

(b) Lighter weight than competing materials, reducing fuel consumption during

transportation.

(c) Extreme durability.

(d) Resistance to chemicals, water and impact.

(e) Better safety and hygiene properties for food packaging.

(f) Excellent thermal and electrical insulation properties.

(g) Relatively inexpensive to produce.

However, plastics waste creates lot of nuisances and degrade environment in a big

way.

2. Pollution problems of plastics - Industrial practices in plastic manufacture can

lead to polluting effluents and the use of toxic intermediates, the exposure to which

can be hazardous. Better industrial practices have led to minimizing exposure of

plant workers to harmful fumes.

There is growing concern about the excess use of plastics, particularly in packaging.

This has been done, in part, to avoid the theft of small objects. The use of plastics

can be reduced through a better choice of container sizes and through the

distribution of liquid products in more concentrated form. A concern is the proper

disposal of waste plastics. Litter results from careless disposal, and decomposition

rates in landfills can be extremely long. Consumers should be persuaded or required

to divert these for recycling or other environmentally acceptable procedures. Marine

pollution arising from disposal of plastics from ships or flow from storm sewers must

be avoided.

Recycling of plastics is desirable because it avoids their accumulation in landfills.

While plastics constitute only about 8 percent by weight or 20 percent by volume of

municipal solid waste, their low density and slowness to decompose makes them a

visible pollutant of public concern. It is evident that the success of recycling is limited

by the development of successful strategies for collection and separation. Recycling

of scrap plastics by manufacturers has been highly successful and has proven

economical, but recovering discarded plastics from consumers is more difficult.

3. Factors affecting recycling of plastics - Recycling and re-utilization of waste

plastics have several advantages. Recycling and re-utilization of waste plastics lead

to a reduction of the use of virgin materials and of the use of energy, thus also a

reduction of carbon dioxide emissions. Economically, in some cases, plastics

recycling may be profitable. However, a number of factors can complicate the

practice of plastics recycling, such as the collection of the plastics waste, separation

of different types of plastics, cleaning of the waste and possible pollution of the

plastics. A further complicating factor is the low-value nature of most of the products

that can be manufactured from recycled plastics. Reusing plastic is preferable to

recycling as it uses less energy and fewer resources.

4. Advantages of reuse and recycle of plastics – It has been observed, to

reduce bad effects of waste plastics, it is better to recycle and re-utilize waste

plastics in environment-friendly manners. As per statistics, about 80% of post-

consumer plastic waste is sent to landfill, 8% is incinerated and only 7% is recycled.

In addition to reducing the amount of plastics waste requiring disposal, recycling and

reuse of plastic can have several other advantages, such as:

(i) Conservation of non-renewable fossil fuels – Plastic production uses 8% of the

world’s oil production, 4% as feedstock and 4% during manufacture.

(ii) Reduced consumption of energy.

(iii) Reduced amounts of solid waste going to landfill.

(iv) Reduced emissions of carbon-dioxide (CO2), nitrogen-oxides (NOx) and sulfur-

dioxide (SO2).

5. Plastic bags and their nuisances - Plastic bags are popular with consumers and

retailers as they are a functional, lightweight, strong, cheap, and hygienic way to

transport food and other products. Most of these go to landfill and garbage heaps

after they are used, and some are recycled. Once littered, plastic bags can find their

way on to our streets, parks and into our waterways. Although plastic bags make up

only a small percentage of all litter, the impact of these bags is nevertheless

significant. Plastic bags create visual pollution problems and can have harmful effects

on aquatic and terrestrial animals. Plastic bags are particularly noticeable

components of the litter stream due to their size and can take a long time to fully

break down. Many carrier bags end up as unsightly litter in trees, streets, parks and

gardens which, besides being ugly, can kill birds, small mammals and other

creatures. Bags that make it to the ocean may be eaten by sea turtles and marine

mammals, who mistake them for jellyfish, with disastrous consequences. In

developed countries billion bags are thrown away every year, most of which are used

only once before disposal. The biggest problem with plastic bags is that they do not

readily break down in the environment. It has been found that, the average plastic

carrier bag is used for five minutes, but takes 500 years to decompose.

Plastic bags are made from ethylene, a gas that is produced as a by-product of oil,

gas and coal production. Ethylene is made into polymers (chains of ethylene

molecules) called polyethylene. This substance, also known as polyethylene or

polythene, is made into pellets which are used by plastic manufacturers to produce a

range of items, including plastic bags.

Plastics can be broadly split into two groups, those that consist of long strands

(thermo softening) and those that also contain short cross-links (thermosetting).

Thermo softening plastic will deform when heated and can be remolded into new

shapes. Thermosetting plastics are much stronger, but once they have been formed

into a shape, they will hold that shape indefinitely, and if heated they will merely

burn.

Recycle and reuse of plastic bags can mitigate environmental problems.

6. Issues relating to plastics – There are about 50 different groups of plastics,

with hundreds of different varieties. All types of plastic are recyclable. To make

sorting and thus recycling easier, the American Society of Plastics Industry

developed a standard marking code to help consumers identify and sort the main

types of plastic. Before recycling, plastics are sorted according to their resin

identification code.The type of plastics (as per the resin identification code) and their

most common uses are given below:

a. Plastic process scrap recycling - Currently most plastic recycling in of the

developed countries are of ‘process scrap’ from industry, i.e. polymers left over from

the production of plastics. This is relatively simple and economical to recycle, as

there is a regular and reliable source and the material is relatively uncontaminated.

This is usually described as reprocessing rather than recycling.

b. Post-use plastic recycling – Post-use plastic can be described as plastic

material arising from products that have undergone a first full service life prior to

being recovered. Households are the biggest source of plastic waste, but recycling

household plastics presents a number of challenges. One of these relates to

collection.

c. Mechanical recycling - Mechanical recycling of plastics refers to processes which

involve the melting, shredding or granulation of waste plastics. Plastics must be

sorted prior to mechanical recycling. Mostly, sorting is done manually. Recently,

technology is being introduced to sort plastics automatically, using various

techniques such as X-ray fluorescence, infrared and near infrared spectroscopy,

electrostatics and flotation. Following sorting, the plastic is either melted down

directly and molded into a new shape, or melted down after being shredded into

flakes and than processed into granules called re-granulate.

d. Chemical or feedstock recycling – Feedstock recycling describes a range of

plastic recovery techniques to make plastics, which break down polymers into their

constituent monomers, which in turn can be used again in refineries, or

petrochemical and chemical production. A range of feedstock recycling technologies

is currently being explored. These include: (i) Pyrolysis, (ii) Hydrogenation, (iii)

Gasification and (iv) Thermal cracking.

Feedstock recycling has a greater flexibility over composition and is more tolerant to

impurities than mechanical recycling, although it is capital intensive and requires

very large quantities of used plastic for reprocessing to be economically viable.

7. Strategies for reduction of Environmental Impact of Plastics -

(a) Reduce the use - Source reduction Retailers and consumers can select products

that use little or no packaging. Select packaging materials that are recycled into new

packaging – such as glass and paper. If people refuse plastic as a packaging

material, the industry will decrease production for that purpose, and the associated

problems such as energy use, pollution, and adverse health effects will diminish.

(b) Reuse containers - Since refillable plastic containers can be reused for many

times, container reuse can lead to a substantial reduction in the demand for

disposable plastic and reduced use of materials and energy, with the consequent

reduced environmental impacts. Container designers will take into account the fate

of the container beyond the point of sale and consider the service the container

provides.

(c) Require producers to take back resins – Get plastic manufacturers directly

involved with plastic disposal and closing the material loop, which can stimulate

them to consider the product’s life cycle from cradle to grave. Make reprocessing

easier by limiting the number of container types and shapes, using only one type of

resin in each container, making collapsible containers, eliminating pigments, using

water-dispersible adhesives for labels, and phasing out associated metals such as

aluminum seals. Container and resin makers can help develop the reprocessing

infrastructure by taking back plastic from consumers.

(d) Legislatively require recycled content – Requiring that all containers be

composed of a percentage of post-consumer material reduces the amount of virgin

material consumed.

(e) Standardize labeling and inform the public – Standardized labels for

“recycled,” “recyclable,” and “made of plastic type X” must be developed for easy

identification.

8. Conclusion – Lots of innovations in recycling of waste plastics have been

introduced in many countries. We have to see, we should not pollute environment

while going for recycling and use of recycled products.

BIBLIOGRAPHY

WHAT IS OUR PURPOSE?

The research project will explore the ways in which plastic bags as a technology have affected

American society throughout history, the environmental controversy that is the plastic bag

particularly in the 21st century, and the case study of the tax on plastic bags in Washington, D.C.

The aim of our exploration is to understand the plastic bag as it relates to public opinion and a

function in society; yet, we will still keep the inner workings of plastics firmly in mind as we

progress, citing scientific principles throughout, especially in terms of the technical poster. We

intend to open this “black box,” as well as to talk about the politics of plastics.

With this controversy in mind, we have interviewed some of the key players in this debate. To

give a balanced view, we will illustrate both sides of the debate, including seeking out further

interview or research material from environmental NGOs, plastics trade associations, and local

businesses. Through our research and discovery of the function of plastics in our society, we

seek to better understand the technology and its uses, whether practical or political

Acknowledgements

We are indebted to James Joseph and Claire Rawlinson in the editorial office and Jessica

Mnatzaganian in the journals production office at the Royal Society. Without their guidance and patience this volume would not have been possible. We also thank Dr J.

P. Myers, Environmental Health Sciences, for his help in preparing text for the section on Green Chemistry.