Racial Differences in Respiratory Impairment, Pneumoconiosis, and Federal Compensation for Western US Indigenous Coal Miners

Rationale: Indigenous populations in the United States face numerous health disparities, but the health of Indigenous workers is less well understood. In a recent surveillance study of active Indigenous coal miners, 3% had coal workers' pneumoconiosis/black lung, and 9% had respiratory impairment. However, occupational lung disease prevalence among Indigenous coal miners has not been directly compared with that among other race/ethnicity groups. Coal miners who are totally disabled from black lung may qualify for U.S. Department of Labor (DOL) compensation benefits, but it is unclear how current federal spirometry criteria affect qualification for Indigenous coal miners. Objectives: To compare findings of pneumoconiosis and respiratory impairment in Indigenous and non-Indigenous coal miners in the western United States and assess federal compensation qualification for Indigenous miners using different spirometry standards. Methods: We used voluntary medical surveillance data from 2002 to 2023 to compare the adjusted odds of pneumoconiosis and respiratory impairment between Indigenous/non-Indigenous coal miners. We examined the proportion of Indigenous miners meeting DOL criteria for federal compensation using different spirometry standards. Results: We identified 691 western U.S. coal miners with at least one year of coal mining employment, 289 Indigenous and 402 non-Indigenous (96% White/Hispanic). Indigenous miners had a greater odds ratio for pneumoconiosis for each additional decade of life (2.47 [95% confidence interval (CI), 1.66-3.68]) compared with non-Indigenous coal miners (1.48 [95% CI, 1.19-1.85]). For each decade, Indigenous coal miners also had a greater adjusted odds ratio for respiratory impairment (1.67 [95% CI, 1.25-2.24]) than non-Indigenous miners (1.06 [95% CI, 0.90-1.25]). Indigenous miners had an additional decline of 71 ml (95% CI, 6-136 ml) in forced expiratory volume in 1 second for each decade of life compared with non-Indigenous coal miners. Using the DOL-mandated Knudson (1976) spirometry standard rather than an Indigenous-specific standard, 6 of 18 (33%) Indigenous miners would not qualify for federal compensation. Conclusions: Indigenous coal miners experience greater adjusted odds for pneumoconiosis and respiratory impairment per decade of life and greater decline in forced expiratory volume in 1 second despite lower smoking rates. Structural inequities exist in federal spirometry requirements for Indigenous miners seeking DOL black lung benefits. Regulatory reform is needed to address barriers to compensation for these underrepresented workers.