Deaths From Coal Workers' Pneumoconiosis in the United States, 2020–2023

Coal workers' pneumoconiosis (CWP) is a preventable, progressive lung disease caused by breathing respirable coal mine dust, a mixture that commonly contains coal, crystalline silica and other silicate minerals. It scars the lungs and steadily reduces lung function, and it can keep progressing after exposure ends. Early disease may cause no symptoms, but advanced disease often brings disability and early death. There is no specific treatment: patients receive supportive care, and those with end-stage disease may receive a lung transplant, after which median survival is 6.6 years. A CDC analysis of death records from 2020 to 2023 shows the disease is still killing workers.

How the deaths were counted

Researchers from CDC's National Institute for Occupational Safety and Health (NIOSH) searched national multiple-cause-of-death data covering 13,098,787 deaths of U.S. residents aged 15 and older for records listing CWP as the underlying or a contributing cause. Those years were the most recent to include each person's usual industry and occupation. They calculated age-adjusted death rates and proportionate mortality ratios (PMRs), which compare observed CWP deaths in an industry or occupation with the number expected; a PMR above 1.0 means more deaths than expected.

Findings

• 1,754 deaths were associated with CWP, 576 with it as the underlying cause and 1,178 as a contributing cause. The age-adjusted death rate was 1.3 per million people a year.
• Deaths rose from 370 in 2020 (1.1 per million) to 462 in 2023 (1.4 per million).
• Who died: 78.8% were 65 or older, 94.8% were male, and 96.5% were White.
• Where: 17 states reported at least 10 deaths. Kentucky (517 deaths; 27.9 per million), West Virginia (334; 38.4), Virginia (281; 8.1) and Pennsylvania (164; 3.3) accounted for 73.9% of all deaths.

Industries and jobs

Industry and occupation were known for 1,748 of the deaths.

Deaths also occurred in industries other than mining. Death certificates record only a person's usual job, and miners may share skills with construction and other trades, moving between the mines and other work because of closures, poor health or other reasons — or entering mining after other long-held jobs.

A reversal

An earlier CDC analysis found CWP deaths falling from 1,002 in 1999 (4.7 per million) to 305 in 2018 (1.0). The recent rise matches reports of growing CWP, and of its most severe form, progressive massive fibrosis, among underground coal miners, especially in central Appalachia. Those increases have been linked to dust rich in crystalline silica and other silicates, particularly where thin coal seams are mined or rock is cut to reach coal.

A 2014 standard lowered the permissible limit for coal mine dust, required more frequent dust sampling and monitoring by mine operators, extended medical surveillance to surface coal miners, and added lung function testing (spirometry). Because CWP usually takes many years to appear — most often in miners with 25 or more years on the job — and people can live long after diagnosis, those changes are unlikely yet to show in death data.

Prevention

The authors point to a comprehensive prevention program: controlling exposure to coal mine dust, detecting disease early and providing medical care, together with continued surveillance. NIOSH's Coal Workers' Health Surveillance Program offers miners health screening, informs those with developing disease of their right to work in a low-dust part of the mine, and tracks the disease. Miners' participation and mine operators' support for screening are essential.

Limitations

• CWP on death certificates was not checked against medical records, and some deaths may have been attributed to related diseases such as silicosis or chronic obstructive pulmonary disease, or never diagnosed.
• Full work histories were not available, so a person's usual job may not reflect where exposure happened.
• The state issuing a death certificate may not be where exposure occurred.
• Rates were calculated on the general population rather than on workers.

Sources

• Jacek M. Mazurek, Katelynn E. Dodd, Girija Syamlal, David J. Blackley and David N. Weissman, "Coal Workers' Pneumoconiosis–Associated Deaths — United States, 2020–2023," Morbidity and Mortality Weekly Report, CDC: https://www.cdc.gov/mmwr/volumes/74/wr/mm7441a1.htm