['Fifty years after the London smog incident, the Milan area (Italy) is still experiencing an air pollution emergency every winter, widely reported in the public media, complete with technical and political discussion, and well-studied short-term associations between air pollution and mortality and hospital admissions. The influence of air pollution on the daily activity of an Accident and Emergency Department have rarely been investigated, other than looking at hospital admissions.', 'To assess the possible effects of high air pollution levels we studied 9881 residents requiring care at the hospital Accident and Emergency triage of Vimercate, a city north of Milan with 25 600 inhabitants during one year.', 'There was no correlation between the number of daily Accident and Emergency admissions and the daily mean of particulate matter less than 10 microm (PM), with a relative risk of 0.97 (95% confidence interval 0.67-1.41) for a 5th to 95th percentile variation of the PM, even after correcting for the day of the week, holidays and climate factors such as temperature and humidity.'] Is hospital Accident and Emergency burden unaffected by today 's air pollution levels?