Page 43 - Curriculum Visions Dynamic Book

Plastics
Another area of concern is in the use of plastics. Because these materials are inert, that is, they do not oxidise, they are insoluble in water and cannot be digested by the organisms that normally cause decay.
Special formulations, used as substitutes for petroleum-based plastics and based on starches from plants may help solve some of these problems for plastics used in packaging. These polymers decompose naturally in the wet conditions of the soil and so will decay in landfill sites.
oxidise: the process of gaining oxygen. This can be part of a controlled chemical reaction, or it can be the result of exposing a substance to the air, where oxidation
(a form of corrosion) will occur slowly, perhaps over months or years.
Organic chemical releases
Sometimes fumes emanating from chemical works can have disastrous effects, as they did in Bhopal, India, in 1984. Here a pesticide plant accidentally allowed water into
a tank of methyl isocyanate. The result was the release of a toxic gas that killed 2500 people and injured hundreds of thousands more.
 A polystyrene cup that will not decay.
 Refuse collection sacks are now being designed
to decompose, as is some packaging.
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