RESUMO
OBJECTIVES: Air pollution has been associated with increased mortality according to studies carried out in the US. The APHEA project (Air Pollution on Health: a European Approach) analyzes the short-term effects in 15 european cities. We evaluated the acute relation between air pollution, mortality, and hospital emergency-room visits in Barcelona, one of the cities participating in the APHEA project. METHODS: Daily variations in total mortality, cardiovascular mortality, respiratory mortality, and emergency-room visits for chronic obstructive pulmonary disease (COPD), and asthma were studied in relation to daily variations in air pollution levels in 1985-1991. Poisson regression was done and temperature, relative humidity, and epidemics of asthma and flu were controlled. Temporal trends and auto-regressive terms were examined. RESULTS: A reduction of about 50 micrograms/m3 in particles and sulfur dioxide was accompanied by a reduction of about 4% and 6% (p < 0.05), respectively, in daily deaths from respiratory and cardiovascular causes and emergency-room visits for COPD. Oxidant pollutants (nitrogen dioxide and ozone) were related positively with cardiovascular mortality and emergency visits for COPD and asthma. The role of ozone was notable, with a reduction in ozone levels of 50 micrograms/m3 originating a 4% reduction in emergency-room visits for COPD and asthma (p < 0.05). CONCLUSIONS: Current levels of air pollutants had an epidemiologically measurable impact on mortality and emergency-room visits in Barcelona. These results were consistent with the findings of similar studies in other european and american cities and with previous studies of emergency-room admissions in Barcelona. These studies suggest the possible toxicity of air pollution.