The potential impact of ozone on materials in the U.K.

Recent reports have highlighted the potential damage caused to a range of media, including materials, by ozone (O3). The limited data available indicate significant damage to rubber products and surface coatings but either insignificant or unquantifiable damage to textiles and other polymeric materials at the range of atmospheric concentrations encountered in the U.K. Materials in the indoor environment have been excluded from economic analyses. Legislation was put in place in 1993 in the U.K. in order to reduce NOx (NOx = NO + NO2) and VOC (volatile organic compounds) emissions from motor vehicles which is likely to result in reduced peak O3 episodes but increased average levels of O3 in urban areas which may result in increased damage to materials. A detailed assessment of the costs of O3 damage to materials is not currently possible because of insufficient information on relevant dose-response functions and the stock at risk. Alternative methods were thus adopted to determine the potential scale of the problem. Scaling of U.S. estimates made in the late 1960s provides a range for the U.K. of £170 million-£345 million yr−1 in current terms. This includes damage to surface coatings and elastomers, and the cost of antiozonant protection applied to rubber goods. Independent estimates were made of the costs of protecting rubber goods in the U.K. These were based on the size of the antiozonant market, and provide cost ranges of £25 million-£63 million yr−1 to manufacturers and £25 million-£189 million yr−1 to consumers. The only rubber goods for which a damage estimate (not including protection costs) could be made were tyres, using data from the U.S.A. and information on annual tyre sales in the U.K. A range of £0-£4 million yr−1 was estimated. The cost of damage to other rubber goods could not be quantified because of a lack of data on both the stock at risk and exposure-response functions. The effect of O3 on the costs of repainting were estimated under scenarios of increased urban concentrations of O3 using damage functions derived from the literature. The cost was estimated to be in the range of £0-£60 million yr−1 for a change from 15 to 20 ppb O3, and £0 to £182 million yr−1 for a change from 15 to 30 ppb O3. The wide ranges derived for effects on surface coatings are a reflection of the uncertainty associated with the dose-response functions used.