Sir, - If Michael Smith of An Taisce had access to any hard evidence to refute my contention that PVC is a relatively benign material, presumably such evidence would have featured prominently in his latest anti-PVC diatribe (October 1st). Instead, he expends considerable effort in countering assertions which I had never advanced in the first instance.
On the substantive issue of the alleged toxicity of PVC, for example, a miscellany of sources is quoted to the effect that incineration of PVC results in dioxin production. This is disingenuous of Mr Smith, as this dioxin connection is readily admitted by the industry and is actually acknowledged in my previous letter. The core of the PVC industry case is based on the reality that dioxin compounds are ubiquitous in the environment (though at very low levels) and their presence is attributable to a wide range of sources - some of which are natural in origin (e.g. forest fires).
Independent scientific trials on both sides of the Atlantic have confirmed that in the context of waste incineration, the presence of even high fractions of PVC does not lead to any increase in dioxin production. In fact, trials conducted in Germany indicated a contrary result - i.e., elevated PVC levels resulted in a small increase in dioxin destruction, as a side effect of the impact of the material in improving incineration conditions.
Mr Smith also attempts to rebut my contention that the safety of PVC is supported by its widespread use in healthcare. I hope your readers won't have failed to notice that here the focus of the attack is switched away from PVC and is directed instead at phthalates - a family of chemicals used as plastic additives and in a myriad of other applications. If An Taisce is interested in opening a separate debate on phthalates safety, our industry will be happy to respond. However, linking these entirely separate topics serves only to confuse and obscure the PVC debate.
Finally, I made no claims whatever regarding the superiority of PVC over traditional window materials, as Mr Smith suggests. My comments related to the use of PVC in a very wide range of construction applications where its versatility and durability are well known and appreciated. - Yours, etc.,
Director, Plastics Industries Association, Lower Baggot Street, Dublin 2.