Impact of acute exposure to air pollution on the cardiorespiratory performance of military firemen

Abstract

The objective of the present study was to determine the impact of acuteshort-term exposure to air pollution on the cardiorespiratoryperformance of military fireman living and working in the city ofGuarujd, Sao Paulo, Brazil. Twenty-five healthy non-smoking firemen aged24 to 45 years had about 1 h of exposure to low and high levels of airpollution. The tests consisted of two phases: phase A, in Bertioga, aand phase B, in Cubatao, a town with low levels of air pollution,polluted town, with a 7-day interval between phases. The volunteersremained in the cities (Bertioga/Cubatao) only for the time required toperform the tests. Cumulative load 10 +/- 2 min-long exertion tests wereperformed on a treadmill, consisting of a 2-min stage at a load of 7km/h, followed by increasing exertion of 1 km h(-1) min(-1) until themaximum individual limit. There were statistically significantdifferences (P < 0.05) in anaerobic threshold (AT) between Cubatao(35.04 +/- 4.91 mL kg(-1) min(-1)) and Bertioga (36.98 +/- 5.62 mLkg(-1) min(-1); P = 0.01), in the heart rate at AT (ATHR; Cubatao 152.08+/- 14.86 bpm, Bertioga 157.44 +/- 13.64 bpm; P = 0.001), and in percentmaximal oxygen consumption at AT (AT%VO2max; Cubatao 64.56 +/- 6.55%,Bertioga 67.40 +/- 5.35%; P = 0.03). However, there were no differencesin VO2max, maximal heart rate or velocity at AT (AT(vel)) observed infiremen between towns. The acute exposure to pollutants in Cubatao, SP,caused a significant reduction in the performance at submaximal levelsof physical exertion.