Spirometric changes in fire-eating subjects in Mexico City

Fire-eating is an activity mainly carried out by inner-city poorest subjects as a way to obtain money. Scant information has been reported concerning the consequences of this activity on lung function.

This study was accomplished in the streets of Mexico City by performing spirometric studies on 30 fire-eaters prior to and after their daily activity; in 16 of these subjects these studies were also conducted after salbutamol inhalation.

All fire-eaters were males, 27.9 +/- 1.1 years of age (mean +/- standard error of the mean). Up to two thirds showed abnormalities in baseline spirometry (11 with an obstructive pattern and 9 with mixed pattern) not related to a smoking habit or drug abuse. Number of years in the fire-eating activity was inversely correlated with FEF50 (r=-0.46, p<0.01) and FEF75 (r=-0.33, p<0.05). Likewise, body mass index was inversely correlated with FEF25 and FEF50. These results were corroborated with multiple regression analysis. At the end of daily fire-eating activity, further diminution of FEF75 was observed (-7.6 +/- 1.4%, p<0.01). Aerosolized salbutamol caused statistically significant increment (p<0.05 to p<0.01) in nearly all spirometric variables, although on an individual basis only 10 of 16 (63%) had positive bronchodilation response.

Fire-eaters showed a mild decrease of airflows, which partially correlated with number of years spent in this activity. After a 1-day fire-eating activity, further airflow limitation increased. Up to 63% of subjects tested improved some spirometric airflow value after salbutamol inhalation.