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There can be few materials that have the capacity to generate debate and polarise opinion quite as much as PVC. From its origins in the 1830s, technological development in the 1920s, through to mass production in the 1960s, PVC along with Nylon has characterised the triumph of 20th Century plastics technology and engineering. Today the world market demand is for around 40 million tonnes, 70% of which is used in construction. PVC's characteristics of durability and resistance to corrosion make it very suitable for above and below ground piping; its near-ubiquity as a window frame material is well known, even notorious, and, with the addition of plasticisers, PVC-based floor coverings have effectively marginalized the once dominant linoleum industry.
Yet in the last couple of decades there has gathered a strong reaction to the material. Though there had been questions asked of PVC before the mid 90s, particularly over associations between production and illness of workers, it was the entering of Greenpeace into the debate that brought doubts to many who thought that PVC was inherently 'safe'. Greenpeace in its introduction to the monograph 'What's wrong with PVC?'6, looked forward to its eventual phasing-out: 'We all stand to gain as the environmental burden of toxic, persistent, bio accumulative chemicals, of hormone disrupters and of heavy metals would be significantly reduced.'
Further research began to confirm much that Greenpeace had alleged. Though sometimes confused and contradictory, findings have led public bodies non-the-less to question their use. In some cases, particularly in medical applications, a policy of substituting other polymers and materials for PVC has been put into effect.
The initial reaction of the PVC industry was denial, but after a period of further research-based and persistent criticism, reaction became more complicit. With the help of external sanctions and a drive to make itself more accountable, the industry has striven to remedy both the toxic elements of PVC product composition and the more dangerous aspects of its production and disposal.
The PVC industry has done much to reduce its overall environmental impact, but critics stand firm in pointing out that the manufacture and some methods of disposal are inherently dangerous, and, as their argument goes, however low the risk of release to the environment of toxic chemicals, it is a risk that society need not, and should not, take.
The argument for PVC: