• Stroke
• transient ischaemic attack (TIA)
• lung injury
• oxydative stress

Evidence accumulated over >50 years of epidemiological and clinical research has established the adverse effects of air pollution on human health.1 2 These studies have formed the basis for legislation to regulate the sources of atmospheric air pollution and to limit the effects of specific air pollutants on both public health and the environment. Efforts to introduce more stringent targets and further improve air quality have been met by legal challenge from industrial groups,3 and therefore understanding the role of individual pollutants is essential to guide effective legislation and public health policy.

Potentially harmful air pollutants include particulate matter, carbon monoxide, nitrogen dioxide, sulfur dioxide, volatile organic compounds and ozone. Acute exposure to fine particulate matter (PM_2.5) has been linked to a range of adverse cardiovascular events including acute myocardial infarction and heart failure, with long-term exposure increasing the lifetime risk of death from coronary heart disease.4 While the effects of fine particulate air pollution on morbidity and mortality are incontrovertible, the impact of other potentially harmful pollutants on cardiovascular health is less certain. In this issue of Heart, Henrotin et al (see page 1990) investigate the effect of short-term ozone exposure on cerebral and cardiac ischaemic events.5