Effects of air pollution on changes in lung function induced by exercise in children with chronic respiratory symptoms.
OBJECTIVE
To investigate how daily variations in ambient air pollution, especially in particles, during the cold of winter affect repeated measurements of baseline lung function and exercise induced bronchial responsiveness among primary school children with chronic respiratory symptoms.


METHODS
During alternate school weeks (maximum five) from February to April 1994, 33 children took part in exercise challenge tests (n=141 tests). The exercise challenges were conducted outdoors in a school yard in the centre of Kuopio, Finland. Spirometric lung functions were measured indoors before the exercise, and 3 and 10 minutes after. Daily mean concentrations of PM(10), black smoke (BS), NO(2), CO, SO(2), and particle size and numbers were monitored at a nearby fixed monitoring site.


RESULTS
Daily variations in ambient air pollution were not associated with enhanced bronchial responsiveness. However, increased concentrations of BS, PM(10), particle numbers, NO(2), and CO were consistently associated with an impairment of baseline lung functions. The reductions in forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV(1)) were 0.5% and 0.6%, respectively, for each 10 microg/m(3) increase in BS (lag 2).


CONCLUSIONS
Particles derived from combustion affect baseline lung function rather than bronchial responsiveness among children with chronic respiratory symptoms.
Timonen
K L
KL
Unit of Environmental Epidemiology, National Public Health Institute, Kuopio, Finland. Kirsi.Timonen@ktl.fi
Pekkanen
J
J
Tiittanen
P
P
Salonen
R O
RO
D000397:Air Pollution / Q000009:adverse effects*; D001249:Asthma / Q000503:physiopathology; D016535:Bronchial Hyperreactivity / Q000209:etiology*; D002648:Child; D002908:Chronic Disease; D015331:Cohort Studies; D004781:Environmental Exposure / Q000009:adverse effects*; D015444:Exercise / Q000502:physiology*; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D008297:Male; D012120:Respiration Disorders / Q000503:physiopathology*; D014797:Vital Capacity / Q000502:physiology