Air pollution and development of respiratory system: A 19-year cohort study among children in Ptolemaida, Greece

Aim: Diachronic study of the function of the respiratory system among children in the city of Ptolemaida. Methods: Concentrations of airborne particles with an aerodynamic diameter ≤ 10μm (PM 10 ) were measured regularly during the study period. Participants of the study were children 10-12 year old who completed a questionnaire about respiratory diseases (Ferris BG), underwent spirometry and anterior rhinomanometry during the first visit (1990-1) and at follow-up (2008-9) (mean follow-up: 19±1.1 years). Results: The average annual concentration of PM 10 was always above the permissible levels. A total of 1086 children were studied initially while 312 of them were examined during the follow-up visit. All were permanent residents in Ptolemaida. Based on the answers to the questionnaire: the prevalence of asthma has remained constant (5.4 vs 6.1%, p=0.85), allergic symptoms increased (16 vs 47.8%, p<0.001) and nasal symptoms were common (92.9 vs 47.3%, p<0.002). Lung function parameters were within predicted values at both visits (FVC: 98.9±12 vs 107.3±14.4% pred., p <0.001, FEV 1 : 98.2±12.5 vs 111.1±15.1%pred., p<0.001 and FEF 25-75 : 96.7±22.7 vs 121.8±34.6%pred., p<0.001). On the other hand, nasal flows were extremely low (flow sum: 302.5±119.7 and 511.1±252.6 ml/sec at follow-up) while 47.1% of the adult group had severe nasal obstruction (flow sum < 500ml/sec). 45.8% of the adults were current smokers. The incidence of asthma, FEV 1 %pred. and nasal flows were not different between smokers and non-smokers. Conclusions: Lung function of children in Ptolemaida developed within predicted values while severe nasal obstruction was particularly frequent among young adults.