High altitude underground mining. Acclimatization and possible toxicological risks.

Summary: Background. Aim of our study was to measure the first responses to hypobaric hypoxia: changes in ventilation minute, heart rate, and hemoglobin saturation which are important parameters involved in the health of mine-workers at high-altitude. Material and Methods. We develop a study of parameters mentioned on Chilean miners working in an underground mine at high altitude, between 3.070 and 3.656 masl, in an unusual shift system consisting of 12-hour daily work during 4 days, and consecutive 4 resting days. The results obtained at high altitude are contrasted with the corresponding for clerks working at 800 masl. Results. Either miners who has work less than 6 months at HA as those who are exposed at their workplace to contaminants, as diesel and others, show Hemoglobin Saturation below 90%. Heart Rate increases in response to exposure to acute and/or chronic hypoxia at high altitude. Miners during their resting period at 800 masl or less show an average heart rate lower than clerks no exposed to high altitude. Average Minute Volume of miners at high altitude, on each and every day of the shift, is higher than the mean volume of clerks at 800 masl. Conclusions. The most of studied miners present acclimatization responses at high altitude in all the studied parameters. The increase in Minute Volume implies a risky condition due to the increase of inhaled toxic inherent to the production process. It appears as an urgency to study the combined effects of hypobaric at high altitude and toxics present at the underground mine.