[Methodology to evaluate occupational exposure to chemical contaminants at high altitude]

This study reviews the current method for assessing exposure to chemical contaminants at high altitude, which is based on the use of Threshold Limit Values (TLV). These TLVs were originally established for work performed at sea level, for 8-hour shifts over a 40-hour work week. Our study analyzes the problem for a specific group of Chilean miners working at altitudes above 3000, and for shifts of up to 12 hours a day. We examined different approaches for the evaluation of exposure to chemical contaminants: adjusting the TLV for work at high altitude and calculating inhaled dose. Since minute ventilation changes at different altitudes, we propose using calculated inhaled dose of the chemical contaminant as the method of choice.