OZONE, TEMPERATURE AND CARDIOVASCULAR MORTALITY

Increasingly, as the harmful effects of climate extremes and air pollution have become delineated, researchers have turned their focus to the interaction of these hazards. In this issue Ren et al, for example, have investigated how ozone modifies the relation between temperature and cardiovascular mortality using data from the US National Morbidity, Mortality, and Air Pollution Study.1 Time series regression models were constructed for 95 large US communities during the summers of 1987–2000. They found a positive interaction, such that for a 10°C increase in temperature, cardiovascular mortality was more than seven times higher …