Occupational exposure to dust in the mining industry context : a short review

Introduction: The exposure to breathable particulates pose a significant threat to human health globally. Several occupational activities can contribute to this problem, being mining one of them. The dust generated from mining activities such: as drilling, crushing, loading, and unloading can reach the alveolar region of the lung, representing an occupational hazard. Miners are considered a high-risk group for respiratory morbidity and premature death since workers usually stay for an extended period of time on the mining front, for instance. The main objective of this short review was to characterise the occupational exposure to dust in the mining context, determining the main exposure values, occurrence circumstances, leading occupational diseases and their prevalence. Methodology: The PRISMA Statement guidelines were used in order to conduct the research. Engineering and health databases and journals were screened and the combinations of the following keywords were used in the first phase: “dust” and “particulate”, “open pit”, “open cast”, “quarry”, “mining industry”, “underground mining” and “extractive industry”. Later, the keywords “pneumoconiosis”, “silicosis” and “respiratory impairment” were added to the study. The prior defined exclusion criteria were date (only papers published after 2015 were considered), type of document (scientific papers and articles in press), type of source (journals and trade publications), language (English only) and a first screening was performed through the titles and abstracts in order to determine the scope. The included articles would have to be related to the main objective and reporting any outcome related to dust occupational exposure. Results: A total of 4,430 records were identified. After applying the exclusion criteria, only 17 remained. The references of the included studies were screened so to add other relevant articles, in the known snowballing technique process, where six more results were found. From those 23 final studies, 18 focused on dust collection processes and data, while five studied the occupational diseases related to the topic. Discussion: The interaction between the different variables – place, equipment, and activity – determine and influence the dust generation and spreading. However, the breathable dust concentration tends to be higher in the milling processes (crushing, concentration and pelletizing), than in the non-milling processes (mining, shop, and office or control rooms). The prevalence of diseases such as silicosis tend to increase with increasing age and may be highest among former smokers. The duration of exposure was also associated with an increase in the prevalence rate; for each additional year of silica exposure, this ratio increase was of about 4%. Conclusions: Mining activities are severely associated with the dust generation process. The overall objectives of the short review were achieved: the actual exposure values to dust were collected, and the circumstances in which it occurs were addressed. This study provided data to be considered in a dust mitigation process.