Prevalencia de carboxihemoglobina en conductores de buses urbanos pertenecientes a una empresa de transporte público en Cuenca 2025

Abstract

Environmental exposure to carbon monoxide (CO), mainly from vehicles, can be assessed by measuring carboxyhemoglobin (COHb) levels. This study evaluated COHb levels in urban bus drivers from a company in Cuenca during November and December 2025 and their relationship with exposure time.The study used non-probabilistic voluntary sampling with operational geographic stratification and selected 60 participants, taking blood samples at the final stops when the drivers were resting. To do this, they previously signed an informed consent form and completed a structured survey, analyzing risk factors such as smoking, traffic time, and working hours. The results showed a COHb prevalence of 65% in the drivers evaluated. No non-smoking drivers had normal COHb levels. In this group, 46.67% were classified as having high levels. Among smokers, 35% had normal values for their condition. In the same group, 18.33% were in the high levels category. These findings suggest that urban transportation involves occupational risk. No statistically significant associations with habits, working conditions, or symptoms were identified, although dizziness showed a value close to the significance threshold (p = 0.0609). It is concluded that exposure in transport workers is influenced by individual factors and working conditions, with carboxyhemoglobin values higher than the reference values established by the WHO for non-smokers and the clinically accepted values for smokers.