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Plastics and the Environment
By:
Indian Centre for Plastics in the Environment, Mumbai*
Scientists have termed plastics as a marvel of modern chemistry. They have
declared discovery and development of plastics as one of the greatest
achievements chemistry has ever made.
Development of Synthetic Plastics (henceforth termed as ‘plastics’) began
during the second half of Nineteenth Century, close to the time when
industrialization began in the Europe and slowly in rest of the world. By
the middle of Twentieth Century many major scientific discovery and
inventions took place in the development of many types of plastics although
the volume remained at a low sphere. However since around 1970’s, the
volume of production of plastics materials increased at a very fast rate
and by 2015 the production at a level of around 250 million Tons is close
to that of Steel on the basis of surface area covered.
Plastics have gained widespread applications from the common household
goods to high technology instruments. Plastics have made significant
contribution in the area of medical safety and health care. Light weight
yet tough, inert, excellent barrier properties, ease of processing into
flexible or rigid products, transparency when desired, low consumption of
energy during its production and transportation - all these attributes have
made plastics an inseparable entity of the modern human life. Plastics
reduce the emission of green house gases and leave lesser Carbon Footprint
on the earth compared to the alternative materials. Plastics save green
house gas emissions and save the earth from global warming. Use of plastics
in Piping, Automobiles, Insulation and Packaging applications saved the
earth from Green House Gases to the tune of about 1.0 GT in the year 2005.
(McKinsey study for ICCA - International Council of Chemical Associations).
Plastics pipes consume least electrical energy to discharge equal volume of
irrigation water for agricultural purpose compared to pipes made of
alternate materials. Plastics have replaced wood in many application areas
saving millions of trees from felling. Packaging is the single largest
application area of plastics. Positive attributes have clearly established
‘preferred’ status for plastics in packaging. Protection, preservation,
light weight, hygiene, cost effectiveness, ease of availability, its
amenability to be produced indifferent forms, sizes and shapes and many
others, make plastics an ideal material of choice for food as well as
non-food packaging.
Although plastics are employed in myriad applications where they actually
conserve natural resources, there are some issues which have been
surrounding the material ever since its growth rate increased.
First it is said that plastics are derived from nonrenewable
resources, viz. oil and hence the usage of plastics should be
curbed.
The reality is that only about 4% of crude oil is used in the entire chain
of petrochemicals of which plastics is only a part. Moreover use of light
weight plastics materials in various applications including in automobiles,
reduces the consumption of fuels to such an extent that it more than
compensates its use of the crude oil for its production. While the economy
of usage of crude oil is always welcome, curbing the use of plastics is not
the solution.
The second aspect of criticism relates to the alleged health
hazards arising out of usage of plastics.
Plastic products are being subjected to in-depth scientific analysis and
they have clearly proved that plastics do not cause any health hazard. In
fact plastic products have been implanted into vital organs like heart
valves clearly disproving the myths. Plastics are used for packaging of
live saving blood and vital pharmaceutical products. Plastics Disposable
Syringes inject the live saving drugs into human and animal bodies. There
are clear international and national regulations / standards for usage of
plastics that comes into contact with food stuffs, pharmaceutical products
and drinking water etc. Therefore, much of the alleged health hazards are
pure scare mongering and not based on scientific facts. The issue of dioxin
emission during the processing / burning of plastics has also been studied
and documented to indicate that plastics and dioxin are not directly
related. It is also documented that air and water emissions of various
gases and other products during the production of plastics are much lesser
compared to the alternative materials for same applications
The third major criticism is its non-biodegradability.
While it is true that plastics are not amenable to biodegradation like
other organic matters, many alternate materials such as glass, metals are
also not biodegradable. Moreover, many of the applications for plastics
arise from the need for the product to be long-lasting. Again, LCA and
other studies carried out the world over clearly prove that the energy
required for production of plastics is much lower than that of alternate
materials. Thus the production and usage of plastics demand minimum energy
in comparison to other materials and therefore non-biodegradability alone
cannot be a consideration while deciding on the appropriate needs of a
material.
Biodegradable / Compostable Plastics have been developed since as early as
in the Seventies (1970’s). In fact most of the major manufacturers of
conventional plastics raw materials from Natural Gas, also manufacture
compostable plastics for limited and specific applications which are
difficult for recycling; for example mulch film in agricultural
application. It is evident that the degradation / composting process
releases carbon dioxide in aerobic condition and methane and carbon dioxide
in anaerobic condition. Both the situations are not desirable as both
carbon dioxide and methane are greenhouse gases. Conventional Plastics
recycling do not create such situation. Recycling is preferred compared to
biodegradation / composting due to fact that recycling help resource
management. Compostable Plastics do not degrade or disappear in to the soil
of its own. It will remain in the open environment if not treated
appropriately. Moreover, composting takes several months even when handled
properly. Some other type of degradable plastics has not been established
as environment friendly.
All these reasons have resulted in keeping the production / demand for
compostable / biodegradable plastics at a miniscule level compared to that
of conventional plastics world over.
Lastly, management of plastics waste is held against the usage of
plastics. Plastics are blamed as the major cause of Solid Waste
problem.
Undoubtedly this is a serious issue mainly due to the poor littering habit
of general mass and inadequate infrastructure for management of solid
waste. Due to this we find all types of dry waste including plastic waste
littered in our surroundings. Even wet waste also is found littered around
the street corners and Plastics and the Environment elsewhere. The reality
is that plastics waste form much less than 10% of the MSW stream in major
Indian cities. There is no problem of disposing the plastics waste when it
is collected in segregated form at source of waste generation. Plastics
waste can be 100% recycled by one process or other. Very thin plastic bags,
though recyclable, are often left behind by the waste pickers when littered
due to economic reason. These very light weight plastic film waste do not
pay a reasonable return to the waste pickers and hence they avoid picking
these up. In India, rigid plastics waste do not create any waste management
issue, as these are collected by the waste pickers in the informal sector
for selling to the waste dealers / recyclers for earning their livelihood.
To avoid the problem of flexible plastics waste management, MoEF,
Government of India has come up with Rules restricting the thickness of
plastic carry bags. Manufacturers and users of multilayered plastics
packaging materials have been assigned the responsibility for assisting the
civic bodies for setting up collection centres for plastics waste. It is
required that the government rules are implemented effectively.
Another most important issue is the plastics waste in the sea and river
water. Marine litter is found in all oceans in the world – not only in most
populated areas but also in area far away from the obvious source of
plastics waste. According to the United Nation’s Joint Group of Experts on
the Scientific Aspects of Marine Pollution (GESAMP), land based sources
account for 80% of marine pollution, rest being from the ships. Although
there is conflicting figures on the volume of marine plastics waste
pollution, however there is no denying that the problem is definitely
serious. There are concerns on how to avoid the marine pollution. Illegal
dumping, proper education on anti-littering near the sea beaches are among
the challenges. Recovery of plastics waste from the oceans also is possible
and is actually practiced in case of larger floating waste. More and more
attention and efforts are required to address the issue. The real solution
lies in the segregation of dry and wet solid waste at the source, creation
of efficient solid waste management infrastructure coupled with
establishment of recycling centres as plastics can be recycled to produce
articles of critical and non – critical applications for mass use
augmenting the concept of resource management.
Apart from the conventional Mechanical Recycling process, alternate
processes of plastics recycling also are required to be encouraged.
Feedstock Recycling and Energy Recovery are very important technologies.
Low-end plastics waste, which often is abandoned by the waste pickers and
conventional recyclers for difficulty in segregation and cleaning, thus
creating a waste management problem, can be disposed of safely by
co-processing in cement kilns. Industrial fuel can be produced from all
types of plastics waste by pyrolysis process. Plasma recycling process can
resolve the issue of disposal of domestic hazardous waste like sanitary
napkins, baby and adult nappies. Plastics waste can be used as an efficient
reducing agent for the manufacture of steel. Plastics waste has been used
to construct better quality asphalt roads. All these processes have been
successfully tried and established. Government of India has made it
mandatory to use plastics waste as per specifications laid down by Indian
Road Congress for constructing all bitumen roads in the country. Use of
plastics waste in co-processing in cement kilns has been approved by the
regulatory authorities.
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