Controlling influences on daily fluctuations of inhalable particles and gas concentrations: Local versus regional and exotic atmospheric pollutants at Puertollano, Spain

Abstract

A 12-month study of PM 10 and gases in the industrial Spanish town of Puertollano reveals striking variations in pollutant concentrations. The normal daily pollution pattern is characterised by a daily double peak for NO x and CO and associated double trough for ozone (morning and evening), a midday atmospheric fumigation peak for SO 2 and PM 10 (1–2 h later in winter), and a late morning through afternoon maximum for ozone (shorter and lower in winter). Superimposed upon this are: (1) seasonal variations, which accentuate the PM 10 and SO 2 mid-morning peaks in winter (when the peak occurs later than in summer), raise NO 2, ozone and background particulate levels during the summer, and favour enhanced levels of NO during the winter; (2) local pollution spikes, particularly those associated with SO 2 release from nearby industrial sources; (3) regional atmospheric stagnation episodes, which enhance concentrations of all pollutants and (4) intrusion of exotic pollutants, notably desert dust from North Africa. Given that air pollutants are known adversely to influence human health, understanding and predicting such diurnal variations in concentrations of inhalable pollutants is especially relevant to susceptible individuals such as asthmatics.