Preventing Silicosis and Tuberculosis

Although it is well recognized that silicosis is one of the most common occupational lung diseases worldwide, exposure to silica dust in the workplace plays an even larger role in global health as it contributes to the Tuberculosis (TB) epidemic. TB is now the most prevalent and most deadly infectious disease worldwide accounting for 1.3 million deaths per year. Silica dust exposure, even without clinically evident silicosis, has been demonstrated to increase the life-long risk of TB. Furthermore, occupational silica dust exposure among workers who are HIV positive in high-burden TB countries is a deadly combination increasing the risk of active TB by 15-fold. Global TB efforts are almost exclusively focused on case identification and treatment with few resources going to prevention. 

Silica dust controls in the workplace can be an effective TB prevention strategy that has yet to be fully understood and embraced by global health funders. Low cost silica dust controls have been demonstrated even in resource constrained informal sector enterprises. Investments in dust controls in the workplace to prevent disease are more cost effective than programs to identify and treat cases of TB. Countries with a high burden of TB and HIV with large mining and construction sectors should be prioritized. There is increased recognition that the global response to the TB epidemic is falling short and that drug-resistant TB is a growing threat. Occupational health professionals can play an instrumental role in making the case that silica dust controls should be incorporated into global health strategies to help meet the UN Sustainable Development Goals target of ending TB by 2030.

It has been well known that a small number of industries play a larger role in TB transmission in countries around the world. These include mining, construction and ceramicware production.

For more than 100 years it has been understood that occupational exposures to silica dust substantially increase TB risk.  Studies have documented that reducing silica exposures decreases the risk of developing TB.  Primary prevention of disease by reducing dust exposures is one of the most cost-effective public health interventions in the workplace.

Targeting some of the highest-risk industries in the mining and construction sectors is an effective strategy to focus limited resources on sources of community infection and spread. Focusing on industries with the highest exposures to silica dust, a potent risk factor for TB, can provide an outsized return on investment for workplace interventions.  For example, it is estimated that more than 60 million workers in India are employed in construction and millions more in both formal and informal mining. Efforts to reduce silica dust exposures of these workers will reduce silicosis, lung cancer, and other respiratory diseases along with TB. It will also reduce infections spreading to families and the community.

The International Commission on Occupational Health (ICOH) published the statement on Preventing Tuberculosis Among Silica Dust Exposed Workers outlining the business case for interventions among mining, construction and other industries with silica dust exposures. The UN General Assembly Declarations on TB in 2018 and 2023 called for commitments to implement primary prevention targeted to these same workplaces.  Unfortunately very little is being done to prevent TB with workplace interventions to reduce this well-known hazard.