Indoor carbon monoxide concentrations in artisanal mining households in Kolwezi, Democratic Republic of the Congo

Introduction: Domestic carbon monoxide exposure represents an emerging public health concern in artisanal mining sites, where residential precarity and high-risk household practices promote the accumulation of this toxic gas. This study estimated indoor carbon monoxide concentrations and identified determinants of elevated levels in artisanal mining community dwellings. Methods: We conducted an analytical cross-sectional study in 155 dwellings located in the Kamilombe artisanal mining site. Carbon monoxide concentrations were measured using a pre-calibrated MSA-ALTAIR 5X multi-gas detector. Statistical analyses employed nonparametric Mann-Whitney and Wilcoxon tests and multivariate quantile regression to identify factors associated with different concentration levels at a significance threshold of α = 5%. Results: The median carbon monoxide concentration was 8 ppm (IQR: 2–16 ppm), with an asymmetric distribution. Most dwellings exhibited structural precarity characteristics. In multivariate quantile regression analysis, tarpaulin construction was associated with significant increases in carbon monoxide concentration across all percentiles, with more pronounced effects at higher concentrations (β = 9.25; 95% CI: 6.47–13.99 at the 75th percentile). Conversely, window presence was associated with significant reductions at the median percentile, more pronounced at higher percentiles (β = -5.75; 95% CI: -10.13 to -2.03; p < 0.001). Conclusion: Our findings suggest that precarious structural housing conditions may contribute to elevated carbon monoxide concentration levels in artisanal mining communities. Improving housing conditions, enhancing ventilation, and reducing domestic pollution sources could constitute important pathways for reducing carbon monoxide exposure in these settings.