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Coal Workers’ Pneumoconiosis–Associated Deaths — United States, 2020–2023

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Coal Workers’ Pneumoconiosis–Associated Deaths — United States, 2020–2023

Summary

What is already known about this topic?

Coal workers’ pneumoconiosis (CWP) is an occupational lung disease caused by inhaling coal mine dust. Although the disease is preventable, new cases and CWP-associated deaths continue to occur.

What is added by this report?

In this exploratory analysis of 2020–2023 national cause-of-death data, 1,754 deaths associated with CWP among U.S. residents aged ≥15 years were reported (age-adjusted CWP death rate = 1.3 per 1 million). Increased risk for CWP-associated death was observed among workers in the mining industry and among construction and extraction workers.

What are the implications for public health practice?

The continuing occurrence of CWP-associated deaths underscores the potential value of a comprehensive prevention program (control of exposures to coal mine dust, early disease detection, and medical care) and supports potential benefits of ongoing surveillance.

The image shows the chest X-ray from a coal worker with pneumoconiosis with text that reads, “Deaths associated with coal workers’ pneumoconiosis continue to occur. Consider work history in patients with signs and symptoms consistent with pneumoconiosis, maintain high index of suspicion for pneumoconiosis when evaluating patients who have worked in the mining industry, and encourage miners to participate in (respiratory) health screening, including chest X-ray and lung function test.”

Abstract

Coal workers’ pneumoconiosis (CWP) is a preventable, progressive occupational lung disease caused by inhaling respirable coal mine dust, a complex mixture commonly containing coal, crystalline silica, and other silicate minerals. Early pneumoconiosis can be asymptomatic, but advanced disease often leads to disability and premature death. To describe CWP-associated mortality among U.S. residents aged ≥15 years by industry and occupation, CDC conducted an exploratory analysis of National Vital Statistics System multiple cause-of-death data for 2020–2023, the most recent years that include information on decedents’ usual industry and occupation. During 2020–2023, CWP was listed on the death certificate of 1,754 decedents (age-adjusted CWP-associated death rate = 1.3 per 1 million). By industry group, the highest number of CWP-associated deaths occurred among workers in the mining industry (1,255). The highest proportionate mortality ratios (PMRs) were among persons employed in the mining industry (PMR = 50.0) and the construction and extraction occupations (6.2). Among workers employed in the mining industry, the highest PMR was among underground mining machine operators (164.6). The continuing occurrence of CWP-associated deaths underscores the potential value of a comprehensive prevention program (maintaining efforts to control occupational coal mine dust exposures, combined with early disease detection efforts and medical care) and supports potential benefits of ongoing surveillance.

Introduction

Coal workers’ pneumoconiosis (CWP) is a preventable, progressive occupational lung disease caused by inhaling respirable coal mine dust, a complex mixture commonly containing coal, crystalline silica, and other silicate minerals (1,2). The disease is characterized by progressive scarring of lung tissue and declining lung function (1,2). Disease progression can occur after cessation of exposure (2,3). Early pneumoconiosis can be asymptomatic, but advanced disease often leads to disability and premature death. No specific treatment exists for CWP; patients with CWP receive supportive care. Lung transplantation can be offered to eligible patients with end-stage CWP; median posttransplant survival is 6.6 years (2,4). Controlling exposure to coal mine dust, combined with early disease detection efforts and medical care, are all important prevention methods to reduce morbidity and mortality associated with CWP (1,2,5,6). To describe CWP-associated mortality among U.S. residents aged ≥15 years by decedents’ usual industry and occupation (i.e., the industry and occupation the decedents engaged in for most of their working life) and to examine associations between CWP-associated deaths and industry and occupation, CDC conducted an exploratory analysis of 2020–2023 National Vital Statistics System (NVSS) multiple cause-of-death data.

Methods

Case Definition and Data Source

CWP-associated decedents were defined as persons whose death record listed the International Classification of Diseases, Tenth Revision, Clinical Modification code J60 (coal workers’ pneumoconiosis) as the underlying or a contributing cause of death.* The NVSS public-use multiple cause-of-death files include 13,098,787 records for U.S. resident decedents aged ≥15 years who died during 2020–2023, the most recent years with information on decedents’ usual industry and occupation. The NVSS files include decedents’ occupation and industry information coded through a collaboration with CDC’s National Institute for Occupational Safety and Health (NIOSH). The 2020–2022 occupation and industry information was coded to 2012 CDC Census Occupation and Industry codes, and the 2023 occupation and industry information was coded to 2018 CDC Census Occupation and Industry codes. Overall, 12,796,979 (97.7%) records included information on industry and occupation.

Data Analyses

Death rates (number of deaths per 1 million persons aged ≥15 years) were based on annual postcensal population estimates as of July 1 of the corresponding year. Death rates were age adjusted by applying age-specific death rates to the 2000 U.S. Census Bureau standard population (Multiple Cause of Death 2018–2023 by Single Race). The state on the death record represents the decedent’s place of legal residence at the time of death.

For analyses, because of small numbers of observations in certain industry and occupation narratives, major industry categories were reduced from 22 to 21 groupings by combining military, miscellaneous, and unclassifiable categories; major occupation categories were reduced from 25 to 23 groupings by combining military, miscellaneous, unclassified, and homemakers categories. One occupation might be listed under multiple industries.

Proportionate mortality ratios (PMRs) (defined as the observed number of deaths with CWP in a specified industry or occupation, divided by the expected number of deaths with CWP) and 95% CIs (assuming Poisson distribution of the data) were calculated by industry and occupation categories. The expected number of deaths was the total number of deaths in an industry or occupation of interest multiplied by a proportion defined as the number of CWP-associated deaths in all industries or occupations, divided by the total number of deaths in all industries or occupations. PMRs were adjusted by 10-year age groups, sex, race, and ethnicity. PMR >1.0 or <1.0 indicates that more or fewer deaths than expected, respectively, were associated with the condition in a specified occupation or industry. PMRs were considered statistically significant if the 95% CI excluded 1.0.

An additional analysis of PMRs was performed by detailed occupation for the decedents whose longest-held job was in the mining industry. For this analysis, to address the updated occupation coding system, detailed 2012 occupation codes were converted to the 2018 coding scheme

Analyses were conducted using CDC Wide-ranging ONline Data for Epidemiologic Research (WONDER) and SAS software (version 9.4; SAS Institute). This activity was reviewed by CDC, deemed not research, and was conducted consistent with applicable federal law and CDC policy.†

Results

CWP-Associated Deaths and Death Rates

During 2020–2023, a total of 1,754 deaths with CWP listed as the underlying (576; 32.8%) or a contributing (1,178; 67.2%) cause of death were identified among U.S. residents aged ≥15 years (Table 1), accounting for 0.01% of 13,098,787 deaths from all causes. Overall, the annualized age-adjusted CWP-associated death rate was 1.3 per 1 million persons. During 2020–2023, the annual number of CWP-associated deaths increased from 370 (death rate = 1.1 per million) in 2020 to 462 (1.4) in 2023. Among CWP-associated deaths, 1,382 (78.8%; age-specific death rate = 6.1 per million persons) occurred among persons aged ≥65 years, 1,663 (94.8%; age-adjusted death rate = 2.8) among males, 1,692 (96.5%; 1.5) among White persons, and 1,715 (97.8%; 1.4) among non-Hispanic persons.

During 2020–2023, 17 states reported at least 10 CWP-associated deaths§ among persons aged ≥15 years. Deaths in four states (Kentucky [517; annualized age-adjusted CWP-associated death rate = 27.9 per million persons], West Virginia [334; 38.4], Virginia [281; 8.1], and Pennsylvania [164; 3.3]) accounted for 1,296 (73.9%) of all CWP-associated decedents.

Industry

Industry and occupation data were available for 1,748 (99.7%) of 1,754 CWP-associated deaths. Among the 21 industry groups, the highest number of CWP-associated deaths occurred among persons employed in the mining industry for most of their working life (1,255; 71.8%), followed by the construction (111; 6.4%) and manufacturing (68; 3.9%) industries (Table 2). PMR among persons working in the mining industry was 50.0, indicating that the observed number of CWP-associated deaths was significantly higher than the expected number of CWP-associated deaths.

Occupation

Among 1,748 workers employed in the 23 occupation groups for most of their working life, the highest number of CWP-associated deaths occurred among persons working in construction and extraction occupations (1,273; 72.8% of CWP-associated deaths), followed by those in transportation and material moving occupations (96; 5.5%). PMR of 6.2 among construction and extraction workers indicated that the observed number of CWP-associated deaths was statistically significantly higher than the expected number of CWP-associated deaths. Among workers in the mining industry, the highest number of CWP-associated deaths occurred among underground mining machine operators (851; PMR = 164.6) followed by other extraction workers (252; PMR = 75.0) (Table 3).

Discussion

CDC previously examined pneumoconiosis mortality by industry and occupation for selected states for 1999–2018 and identified similar industries (i.e., the coal mining and construction industries) and occupations (i.e., mining machine operators) associated with CWP deaths (7). This report expands information on industries and occupations associated with CWP deaths and reinforces the value of analyzing mortality data by industry and occupation.

Although CWP deaths would be expected to be limited to the workers in the mining industry, they were also identified across a range of other industries. The identification of CWP-associated deaths among workers employed in industries other than mining might be explained, in part, by the recording of only one occupation that the decedent held for most of their working life (i.e., usual occupation) on the death certificate and its associated industry. Coal mine workers might have skills that are shared with other industries (such as construction) and might move between the coal mine and other industries because of mine operation closures, poor health, or other reasons. Workers might also leave other long-held jobs and enter the coal mine industry.

A previous CDC analysis found a declining trend in CWP-associated deaths from 1999 (1,002 deaths; age-adjusted rate = 4.7 per million) to 2018 (305; 1.0) (7). In this report, the annual number of CWP-associated deaths increased from 370 (death rate = 1.1 per million) in 2020 to 462 (1.4) in 2023. This increase in CWP-associated deaths is consistent with recent findings indicating an increase in CWP prevalence and its most severe form (progressive massive fibrosis, characterized by the development of large, dense, fibrotic masses in the lungs) among coal miners working underground, particularly in central Appalachia (8,9). These trends in CWP prevalence have been associated with exposure to coal mine dust with a high content of crystalline silica and other silicate minerals, specifically in operations involving mining thin coal seams or cutting rock to access coal (6,10).

In 2014, a revised standard decreased the existing permissible limit of exposure to respirable coal mine dust, increased dust sampling frequency and monitoring by mine operators, extended medical surveillance to include surface coal miners, and expanded medical surveillance testing to include spirometry. A long latency is typical between first exposure to coal mine dust and diagnosis of CWP, with disease most frequently identified in miners with ≥25 years’ tenure (1,2). Because persons with CWP can live for many years after diagnosis, the latency until death is even longer. Thus, insufficient time would likely have elapsed for the changes in regulations to substantially affect the findings in this report. Continued monitoring of mortality trends, with attention to industry and occupation, is important to assess the effects of these changes.

Limitations

The findings in this report are subject to at least six limitations. First, CWP reported on death certificates were not validated using medical records. Some CWP deaths might have been attributed to other chronic respiratory diseases caused by exposure to coal mine dust (e.g., silicosis or chronic obstructive pulmonary disease) (1,2). Thus, CWP deaths might have been overascertained or underascertained. Second, some decedents might have never received a diagnosis of CWP (6). Therefore, occupations well-known to be associated with CWP deaths (e.g., underground mining machine operator) (8) might be underreported. Third, complete work histories were not available to enable assessment of changes in employment. Death certificate data relating to the decedent’s usual occupation and industry might not always reflect jobs in which causative exposures occurred. Some miners might have changed their jobs within the mining industry (e.g., miners with radiographic evidence of CWP moving to a low-dust mine environment under part 90 rights**), changed to another industry, or left the workforce; thus, PMRs might not accurately represent occupational risk. Fourth, the state issuing a death certificate might not be the state in which the decedent’s exposures occurred. Fifth, mortality rates might not correctly represent CWP frequency. The rates were calculated using data on the general population that include those who are not at an occupational risk for developing CWP. Finally, small numbers of deaths among certain groups did not permit a more detailed characterization of CWP-associated deaths.

Implications for Public Health Practice

The continuing occurrence of CWP-associated deaths underscores the potential value of a comprehensive prevention program, including control of exposures to coal mine dust, early disease detection, and medical care (1,2,5,6) and supports potential benefits of ongoing surveillance. CDC’s NIOSH Coal Workers’ Health Surveillance Program provides information on diseases caused by coal mine dust, offers health screening to miners, informs miners with developing pneumoconiosis about their rights to work in a low-dust environment of the mine, and monitors disease occurrence. Miners’ awareness and participation in the Coal Workers’ Health Surveillance Program and mine operators’ support for respiratory health screenings are essential parts of the prevention efforts to reduce CWP morbidity and mortality.

1Respiratory Health Division, National Institute for Occupational Safety and Health, CDC.

References

  1. US Department of Health and Human Services, CDC, National Institute for Occupational Safety and Health. Current intelligence bulletin 64: coal mine dust exposures and associated health outcomes: a review of information published since 1995. Cincinnati, OH: US Department of Health and Human Services, CDC, National Institute for Occupational Safety and Health; 2011. NIOSH publication no. 2011–172. https://www.cdc.gov/niosh/docs/2011-172/pdfs/2011-172.pdf
  2. Go LHT, Cohen RA. Coal workers’ pneumoconiosis and other mining-related lung disease: new manifestations of illness in an age-old occupation. Clin Chest Med 2020;41:687–96. https://doi.org/10.1016/j.ccm.2020.08.002
  3. Hall NB, Blackley DJ, Markle T, Crum JB, Halldin CN, Laney AS. Postexposure progression of pneumoconiosis among former Appalachian coal miners. Am J Ind Med 2022;65:953–8. https://doi.org/10.1002/ajim.23431
  4. Blackley DJ, Halldin CN, Hayanga JWA, Laney AS. Transplantation for work-related lung disease in the USA. Occup Environ Med 2020;77:790–4. https://doi.org/10.1136/oemed-2020-106578
  5. Colinet JF, Halldin CN, Schall J; US Department of Health and Human Services, CDC, National Institute for Occupational Safety and Health. Mining product: guidelines for the control and monitoring of methane gas on continuous mining operations. Pittsburgh PA: US Department of Health and Human Services, CDC, National Institute for Occupational Safety and Health; 2021. NIOSH publication no. 2021–119, IC 9532. https://doi.org/10.26616/NIOSHPUB2021119
  6. Hall NB, Blackley DJ, Halldin CN, Laney AS. Current review of pneumoconiosis among US coal miners. Curr Environ Health Rep 2019;6:137–47. https://doi.org/10.1007/s40572-019-00237-5
  7. Bell JL, Mazurek JM. Trends in pneumoconiosis deaths—United States, 1999–2018. MMWR Morb Mortal Wkly Rep 2020;69:693–8. https://doi.org/10.15585/mmwr.mm6923a1
  8. Blackley DJ, Crum JB, Halldin CN, Storey E, Laney AS. Resurgence of progressive massive fibrosis in coal miners—Eastern Kentucky, 2016. MMWR Morb Mortal Wkly Rep 2016;65:1385–9. https://doi.org/10.15585/mmwr.mm6549a1
  9. Blackley DJ, Halldin CN, Laney AS. Continued increase in prevalence of coal workers’ pneumoconiosis in the United States, 1970–2017. Am J Public Health 2018;108:1220–2. https://doi.org/10.2105/AJPH.2018.304517
  10. Doney BC, Blackley D, Hale JM, et al. Respirable coal mine dust in underground mines, United States, 1982–2017. Am J Ind Med 2019;62:478–85. https://doi.org/10.1002/ajim.22974

TABLE 1. Characteristics of decedents with coal workers’ pneumoconiosis and age-adjusted coal workers’ pneumoconiosis–associated death rates among persons aged ≥15 years — United States, 2020–2023Return to your place in the text
Characteristic CWP-associated deaths,* no. (%) Death rate† (95% CI)
Total 1,754 (100.0) 1.3 (1.3–1.4)
Age group, yrs§
15–44 62 (3.5) 0.1 (0.1–0.2)
45–64 310 (17.7) 0.9 (0.8–1.0)
≥65 1,382 (78.8) 6.1 (5.7–6.4)
Sex
Female 91 (5.2) 0.1 (0.1–0.2)
Male 1,663 (94.8) 2.8 (2.7–3.0)
Race
Black or African American 45 (2.6) 0.3 (0.2–0. 5)
White 1,692 (96.5) 1.5 (1.5–1.6)
Multiple races 17 (1.0) —**
Ethnicity
Hispanic or Latino 39 (2.2) 0.3 (0.2–0.4)
Non-Hispanic 1,715 (97.8) 1.4 (1.4–1.5)
Year
2020 370 (21.1) 1.1 (1.0–1.2)
2021 459 (26.2) 1.4 (1.3–1.5)
2022 463 (26.4) 1.4 (1.2–1.5)
2023 462 (26.3) 1.4 (1.2–1.5)
State of residence
≥10 deaths††
  Kentucky 517 (29.5) 27.9 (25.5–30.4)
  West Virginia 334 (19.0) 38.4 (34.2–42.5)
  Virginia 281 (16.0) 8.1 (7.2–9.1)
  Pennsylvania 164 (9.4) 3.3 (2.8–3.9)
  Tennessee 82 (4.7) 2.9 (2.3–3.6)
  Colorado 48 (2.7) 2.3 (1.7–3.1)
  Alabama 21 (1.2) 1.0 (0.6–1.5)
  South Carolina 20 (1.1) 0.9 (0.5–1.4)
  Ohio 41 (2.3) 0.9 (0.6–1.2)
  Illinois 30 (1.7) 0.6 (0.4–0.8)
  Texas 43 (2.5) 0.4 (0.3–0.6)
  Florida 25 (1.4) 0.3 (0.2–0.4)
  Indiana 18 (1.0) —**
  Wisconsin 16 (0.9) —**
  New Mexico 15 (0.9) —**
  North Carolina 14 (0.8) —**
  Utah 14 (0.8) —**
All other states§§ 71 (4.0) 0.1 (0.1–0.2)

Source: CDC Wide-ranging ONline Data for Epidemiologic Research (WONDER) online databases, Multiple Cause of Death, 2018-2023, Single Race Request.
Abbreviations: AI/AN = American Indian or Alaska Native; A/PI = Asian or Pacific Islander; CWP = coal workers’ pneumoconiosis; NCHS = National Center for Health Statistics.
* Death records with International Classification of Diseases, Tenth Revision, Clinical Modification multiple cause-of-death code J60 (coal workers’ pneumoconiosis).
† Age-adjusted CWP-associated death rates (deaths per 1 million persons) were calculated by applying age-specific death rates to the 2000 U.S. Census Bureau standard population age distribution. Multiple Cause of Death 1999-2020
§ Age-specific CWP-associated deaths per 1 million persons. The minimum age to work in a mine is 18 years; however, Bureau of Labor Statistics data

TABLE 2. Industries and occupations with coal workers’ pneumoconiosis–associated deaths and proportionate mortality ratio among persons aged ≥15 years — selected U.S. jurisdictions, 2020–2023Return to your place in the text
Characteristic No. of deaths from all causes CWP-associated deaths,*
no. (%)		 PMR† (95% CI)
Total§ 12,796,979 1,748 (100) —
Industry
Agriculture 270,274 15 (0.9) 0.3 (0.2–0.5)
Mining 91,110 1,255 (71.8) 50.0 (47.3–52.9)**
Construction 946,095 111 (6.4) 0.5 (0.4–0.6)
Manufacturing 1,568,911 68 (3.9) 0.3 (0.2–0.3)
Retail trade 891,149 18 (1.0) 0.2 (0.1–0.3)
Transportation and warehousing 668,960 42 (2.4) 0.3 (0.2–0.4)
Administrative and support and waste management and remediation services 302,018 21 (1.2) 0.5 (0.3–0.8)
Health care and social assistance 1,118,129 21 (1.2) 0.3 (0.2–0.5)
Accommodation and food services 467,120 18 (1.0) 0.4 (0.3–0.7)
Other services (except public administration) 598,929 41 (2.3) 0.5 (0.3–0.6)
Public administration 598,745 21 (1.2) 0.2 (0.1–0.3)
Military, miscellaneous, or unclassifiable 2,744,071 79 (4.5) 0.4 (0.3–0.5)
All other industries†† 2,531,468 38 (2.2) —
Occupation
Management 1,073,693 41 (2.3) 0.2 (0.1–0.3)
Business and financial operations 329,310 10 (0.6) 0.2 (0.1–0.4)
Community and social services 172,892 12 (0.7) 0.5 (0.3–1.0)
Protective service 227,043 13 (0.7) 0.3 (0.2–0.5)
Food preparation and serving related 372,610 12 (0.7) 0.5 (0.3–0.9)
Building and grounds cleaning and maintenance 385,595 37 (2.1) 0.8 (0.6–1.1)
Sales and related 884,097 19 (1.1) 0.1 (0.1–0.2)
Construction and extraction 854,943 1,273 (72.8) 6.2 (5.8–6.5)**
Installation, maintenance, and repair 448,690 43 (2.5) 0.4 (0.3–0.5)
Production 955,637 55 (3.1) 0.3 (0.3–0.5)
Transportation and material moving 897,877 96 (5.5) 0.6 (0.5–0.7)
Military, miscellaneous, unclassifiable, and homemakers 2,674,437 83 (4.7) 0.4 (0.4–0.6)
All other occupations§§ 3,520,155 54 (3.1)           —

Source: National Vital Statistics System public use multiple cause files 2020–2023. Data Access – Vital Statistics Online | CDC
Abbreviations: CWP = coal workers’ pneumoconiosis; PMR = proportionate mortality ratio.
* Death records with International Classification of Diseases, Tenth Revision, Clinical Modification multiple cause-of-death code J60 (coal workers’ pneumoconiosis).
† PMR was defined as the observed number of deaths with CWP in a specified occupation, divided by the expected number of deaths with CWP. The expected number of deaths was the total number of deaths in the occupation of interest multiplied by a proportion defined as the number of CWP-associated deaths in all occupations, divided by the total number of deaths in all occupations. CWP-associated PMRs were adjusted by 10-year age groups, sex, race, and ethnicity.
§ In 2020, 47 jurisdictions participated in the industry and occupation information coding program (Arizona, North Carolina, Rhode Island, and the District of Columbia did not participate). Iowa participated in the program in 2020, but the data were inconsistent with those from other jurisdictions and were excluded. In 2021, a total of 49 jurisdictions participated (Rhode Island and the District of Columbia did not participate). In 2022 and 2023, a total of 52 jurisdictions (50 states, New York City, and the District of Columbia) participated in the program. Industry and Occupation Data Mortality 2020

TABLE 3. Occupations with coal workers’ pneumoconiosis–associated deaths and proportionate mortality ratio among persons aged ≥15 years employed in the mining industry — selected U.S. jurisdictions,* 2020–2023Return to your place in the text
Occupation in mining industry† No. of deaths from all causes (N = 91,110) CWP-associated deaths,§ no. (%)
(n = 1,255)		 PMR (95% CI)
Underground mining machine operators** 16,218 851 (67.8) 164.6 (153.7–176.0)††
Other extraction workers§§ 12,609 252 (20.1) 75.0 (66.1–84.9)††
Electricians 1,365 25 (2.0) 58.0 (37.6–85.7)††
Construction equipment operators 2,849 25 (2.0) 29.5 (19.1–43.5)††
Driver/sales workers and truck drivers 3,309 22 (1.8) 24.2 (15.2–36.7)††
First-line supervisors of construction trades and extraction workers 4,879 11 (0.9) 7.9 (3.9–14.1)††
All other occupations¶¶ 49,881 69 (5.5) 5.3 (4.1–6.7)††

Source: National Vital Statistics System public use multiple cause files 2020–2023. Data Access – Vital Statistics Online | CDC
Abbreviations: CWP = coal workers’ pneumoconiosis; PMR = proportionate mortality ratio.
* In 2020, 47 jurisdictions participated in the industry and occupation information coding program (Arizona, North Carolina, Rhode Island, and the District of Columbia did not participate). Iowa participated in the program in 2020, but the data were inconsistent with those from other jurisdictions and were excluded. In 2021, a total of 49 jurisdictions participated (Rhode Island and the District of Columbia did not participate). In 2022 and 2023, a total of 52 jurisdictions (50 states, New York City, and the District of Columbia) participated in the program. Industry and Occupation Data Mortality 2020

Suggested citation for this article: Mazurek JM, Dodd KE, Syamlal G, Blackley DJ, Weissman DN. Coal Workers’ Pneumoconiosis–Associated Deaths — United States, 2020–2023. MMWR Morb Mortal Wkly Rep 2025;74:627–633. DOI: http://dx.doi.org/10.15585/mmwr.mm7441a1


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