Environmental concerns ozone layer depletion

Evidence that many of these compounds can have adverse effects on the immune, endocrine and nervous systems and that some are carcinogenic has grown during the last decade. The role of chlorofluorocarbons (CFCs) and of methyl bromide in the ozone layer depletion is well established (ref. 3).It is therefore not surprising that many halogenated derivatives are cast as environmental and health villains by various concerned groups who call for total phase out of chlorine and chlorinated hydrocarbons. 

The synthesis of fluoropolymers in C02 is of particular interest since these polymers have historically been prepared in chlorofluorocarbons (CFCs) and other fluorinated solvents, as well as in water. Due to the association of CFCs with ozone-layer depletion, these solvents have been banned and replacement solvents must be found. Alternative fluorinated solvents are expensive and also have environmental concerns. 

In the early to mid 1970s, hairspray sales declined even further because of environmental pressures to restrict the use of fluorocarbons in aerosol products. The largest drop in hairspray sales occurred in 1975, after Roland and Molina theorized how fluorocarbons deplete the ozone layer in the stratosphere. For additional details on the rise and the decline in hairspray sales, see the article by Root [53]. As indicated in the introductory section to this chapter, a great deal of current research is concerned with lowering VOCs in hair care products, and in particular in hairsprays, and the California (CARD) regulations outlined in the introduction are the driving force behind these efforts. 

Chemicals such as CFCs and nitrogen oxides that damage the ozone layer are known as ozone-depleting chemicals (ODCs). Concern about the use of chlorofluorocarbons in particular led to the signing of the Montreal Protocol and the subsequent search for alternatives, as discussed earlier. The concerted international effort to resolve this situation remains, despite setbacks and complexities, the most successful environmental intervention achieved to date. 

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