Impact of automobile-related air pollution on the ventilatory function of toll highway workers in Dakar

Abstract

Background: Epidemiological studies have reported associations between air pollution and the risk of developing pulmonary diseases. Dakar, the capital of Senegal, is currently experiencing rapid urbanization with the development of new infrastructures such as the toll highway. The traffic on this road is heavy, which could be a significant source of air pollution. Our study aimed to assess the ventilatory function of toll highway workers in Dakar (EIFFAGE agents) exposed to traffic-related air pollution.

Methods: The study was conducted between March 2018 and October 2020 on a cohort of 122 toll highway workers in the Dakar region. Data were collected on work duration, lifestyle, and anthropometric parameters (age, body mass index: BMI). Ventilatory function was assessed using a spirometer (Spirobank II). The level of air pollution in the study area was assessed.

Results: The agents worked 48 hours per week, with shifts of 8 hours per day. None of the participants had a known history of respiratory disease. Spirometric evaluation showed that 14% of participants had ventilatory disorders: 3% had asthma, 7% had chronic obstructive pulmonary disease (COPD), and 4% had probable isolated pulmonary restriction. The risk of developing asthma or restrictive lung disease was not statistically significant in smokers compared to non-smokers. However, smoking appeared to significantly increase the risk of developing COPD [p = 0.0002; OR (95% CI): 5.79 (2.28-14.07)]. Moreover, the study area is highly polluted (with monthly concentrations 180 to 220 µg/m³ and 60 to 120 µg/m³ for PM10 and PM2.5, respectively).

Conclusion: The road traffic on the Dakar toll highway is a significant source of air pollution to which agents may be exposed. This exposure could trigger or worsen ventilatory disorders such as asthma or COPD. Preventive measures are essential to mitigate the harmful effects of automobile-related air pollution.