BACKGROUND: It is known that air borne particulates are closely related with the respiratory symptoms and peak expiratory flow (PEF) in patients with respiratory diseases. In Korea, concentrations of airborne dust and inhalable particulates are dramatically increased by the Yellow sand phenomenon, especially in springtime. OBJECTIVE: This study was performed to evaluate the effect of Yellow sand-related airborne dust on the respiratory symptoms and pulmonary function of patients with bronchial asthma. METHOD: 21 non-smoking, tree pollen non-sensitized subjects with bronchial asthma in Seoul were included in this study. For each subject, asthma and rhinoconjunctivitis symptoms were recorded by self-administered standardized questionnaire and by monitoring PEF between April and May 2000. Symptom score and diurnal variability of PEF were compared with the levels of inhalable particulate matter (PM10) checked in that time at 25 points in Seoul. RESULTS: 15 (71.4%) of the enrolled subjects successfully finished this study. There was no statistically significant relationship between the increment of Yellow sand-related PM10 and respiratory symptom or PEF variability. Of the 15 subjects, there were increased symptoms for the eye in 2 (13.3%) subjects, nose in 3 (20.0%), and sinus in 1 (6.7%), which were associated with Yellow sand-related increase of airborne dust levels. 5 (33.3%) subjects showed changes of PEF variability proportional to the change of PM10. CONCLUSION: Meteorological phenomenon related with Yellow sand has a potential risk of aggravating the upper respiratory tract symptoms and of deteriorating pulmonary functions in patients with asthma.
Asthma* ; Dust ; Humans ; Korea ; Nose ; Particulate Matter ; Pollen ; Respiratory System ; Seoul ; Silicon Dioxide* ; Surveys and Questionnaires