An Evaluation of the Environmental and Health Effects of Vehicle Exhaust Catalysts in the United Kingdom

• Published in: Environmental health perspectives Vol. 112; no. 2; pp. 132 - 141
• Main Authors: Hutchinson, Emma J., Peter J. G. Pearson
• Format: Journal Article
• Language: English
• Published: Research Triangle Park National Institute of Environmental Health Sciences. National Institutes of Health. Department of Health, Education and Welfare 01.02.2004; National Institute of Environmental Health Sciences
• Subjects: Air pollution; Automobiles; Dose response relationship; Emissions reduction; Health benefits; Hospital admissions; Mortality; Platinum; Pollutant emissions; Traffic estimation; British Isles
• ISSN: 0091-6765; 1552-9924
• DOI: 10.1289/ehp.6349

Since 1993, all new gasoline-engine automobiles in the United Kingdom have been supplied with three-way vehicle exhaust catalytic converters (VECs) containing platinum, palladium, and rhodium, to comply with European Commission Stage I limits on emissions of regulated pollutants: carbon monoxide, hydrocarbons, and oxides of nitrogen. We conducted a physical and economic evaluation of the environmental and health benefits from a reduction in emissions through this mandated environmental technology against the costs, with reference to urban areas in Great Britain. We made both an ex post assessment-based on available data to 1998-and an ex ante assessment-projected to 2005, the year when full penetration of VECs into the fleet is expected. Substantial health benefits in excess of the costs of VECs were indicated: By 1998 the estimated net societal health benefits were approximately £500 million, and by 2005 they were estimated to rise to as much as £2 billion. We also found through environmental surveys that although lead in road dust has fallen by 50% in urban areas, platinum accumulations near roads have risen significantly, up to 90-fold higher than natural background levels. This rapid accumulation of platinum suggests further monitoring is warranted, although as yet there is no evidence of adverse health effects.