Mining

Participating core and specialty programs: Exposure Assessment and Personal Protective Technology.

Industry, academia, and other government agencies use NIOSH information to reduce exposure to hazardous airborne contaminants to reduce lung cancer and mesothelioma in mining workers.

Health Outcome Research Focus Worker population Research Type
A Lung cancer, mesothelioma Exposure to elongate mineral particles (especially taconite) Metal/non-metal mines Basic/etiologic
B Lung cancer Exposure to diesel exhaust Metal/non-metal; coal; stone, sand and gravel mines Intervention
C Lung cancer Develop more accurate and timely monitoring of crystalline silica Metal/non-metal; coal; stone, sand and gravel mines Basic/etiologic

Intervention

D Lung cancer Exposure to crystalline silica Metal/non-metal; coal; stone, sand and gravel mines Basic/etiologic

Intervention

E Lung cancer Exposure assessment for known or suspected carcinogens (e.g., radon) Underground mines Basic/etiologic

Activity Goal 1.8.1 (Basic/Etiologic Research): Conduct basic/etiologic research to better understand relationship between exposures to hazardous airborne contaminants and lung cancer and mesothelioma among mining workers.

Activity Goal 1.8.2 (Intervention Research): Conduct studies to develop and assess the effectiveness of crystalline silica and diesel exposure interventions to reduce exposures to prevent lung cancer among mining workers.

Burden

Extracting and processing mined materials can result in overexposures to several hazardous airborne contaminants, including mine dust such as elongate mineral particles (EMP) and crystalline silica dust and diesel exhaust. Mine Safety and Health Administration (MHSA) compliance data demonstrates overexposures to these airborne contaminants at rates as high as 24%. In addition, mining environments can be sources of high exposures to radon gas and its radioactive decay progeny [Daniels and Schubauer-Berigan 2017]. Radon levels are highest in uranium mines, but are also elevated in other hard-rock mines. The International Agency for Research on Cancer (IARC) [2017] classifies crystalline silica, diesel engine exhaust and radon as carcinogenic to humans. In addition, miners suffer from higher rates of lung cancer and mesothelioma than other workers which can be caused by these agents or asbestos and elongate mineral particles with asbestos-like effects. These diseases can have a severe impact on affected miners and be disabling or even fatal. A recent study estimates that 10-23% of lung cancers among miners are likely attributable to their work [Groenewald et al., 2017]. In 2007, a mesothelioma cluster of 58 cases was found in 72,000 former taconite miners who worked in a large iron range in Minnesota, while the expected occupational mesothelioma rate is much lower at 1 per 200,000 workers [Minnesota Department of Health 2007]. Asbestos has been found in many mines, even where the product mined was not asbestos; the National Occupational Health Survey of Mining recorded detectable asbestos in settled dust collected from at least one mine extracting 21 different non-asbestos commodities [NIOSH 1996]. MSHA sampling data collected (2000-2003) in 123 mines of various commodities showed that at 15% of sampled mines, 8% of personal samples had asbestos fiber concentrations in excess of the OSHA regulated concentration of 0.1 fibers/cc [OSHA 2005].

Need

There is need for a range of work to reduce the burden of dust, diesel, and radon-related respiratory malignancies in mining. Basic/etiologic research is needed to improve methods for exposure assessment for most lung carcinogens in the mining environment. Improvements might include real or near-real time silica exposure monitoring, improved detection thresholds for silica exposure assessment and better approaches to characterizing EMP exposures. Exposure assessment research is also needed for radon and other known or suspected carcinogens in underground mines. In addition, work is needed to understand the relative toxicities of various EMP and to improve the ability to predict which EMP will have asbestos-like health effects (see NIOSH Roadmap 2011). Intervention research is needed to improve engineering controls and document the impact of interventions on dust exposure levels and associated cancer risk. For diesel-powered equipment, the need is to reduce hazardous emissions from older engines being used in mines. NIOSH has extensive laboratories for developing and testing diesel controls, and these facilities are served by a dedicated team with two decades of experience and worldwide recognition for their diesel expertise. NIOSH also has expertise, partnerships, and cohorts available to study the association between low-level radon exposure and lung cancer risk.

Daniels RD, Schubauer-Berigan MK. [2017]. Radon in U.S. workplaces: A review. Radiat Prot Dosimetry 16:1-9, doi:10.1093/rpd/ncx007

Groenewold M, Brown L, Smith E, Pana-Cryan R, Schnorr T [2017]. An estimate of the total number of incident occupational injuries and illnesses occurring in the United States in 2012. Manuscript in preparation.

International Agency for Research on Cancer [2017]. Agents classified by the IARC monographs, volumes 1-119. Lyon, France: World Health Organization, International Agency for Research on Cancer, http://monographs.iarc.fr/ENG/Classification/external icon

NIOSH. [2011]. Asbestos Fibers and Other Elongate Mineral Particles: State of the Science and Roadmap for Research. Cincinnati, OH: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication. DHHS (NIOSH) Publication No. 2011-159. https://www.cdc.gov/niosh/docs/2011-159/default.html

NIOSH [1996]. National Occupational Health Survey of Mining. Cincinnati, OH: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication. DHHS (NIOSH) Publication No. 2011-159 https://www.cdc.gov/niosh/docs/96-136/

Minnesota Department of Health [2007]. Mesothelioma in Northeastern Minnesota and Two Occupational Cohorts: 2007 Update. St Paul, Minnesota: Minnesota Department of Health, Center for Occupational Health and Safety, Chronic Disease and Environmental Epidemiology Section, https://www.leg.state.mn.us/docs/2007/other/070751.pdfexternal icon

OSHA [2005]. Asbestos exposure limit. Proposed Rule. Fed Regist 70(145):43950 (to be codified at 30 CFR Parts 56, 57, and 71).

Page last reviewed: April 24, 2018