Collaborating centres

Case Studies

The Americas Silicosis Initiative

When Chilean artisans worked in the past, they used hand tools to artfully shape and cut stone. Today, craftsman working in small open-air settings with two to four workers, use power tools for the same tasks. While efficient, these contemporary tools pose a major health risk by generating dust with high levels of airborne crystalline silica. When workers breathe in this dust, it can result in silicosis, a serious but preventable lung disease. Occupational exposure to crystalline silica inhaled in the lungs is also associated with lung cancer, pulmonary tuberculosis and airway diseases, and may be related to the development of autoimmune disorders, chronic renal disease, and other adverse health effects.

Concerned about these threats, the Chilean National Institute for Public Health (ISP), invited three industrial hygienists from CDC’s National Institute for Occupational Safety and Health (NIOSH) to examine high-risk work conditions among ornamental stone carvers in Pelequén, Chile (both ISP and NIOSH are WHO Collaborating Centres in Occupational Health). A NIOSH industrial hygienist said “the silica dust levels were some of the highest I’ve seen anywhere in the world – and there were no controls to prevent silicosis.” NIOSH plans to assist ISP in implementing interventions to introduce dust control measures in these small shops. NIOSH has expertise in all aspects of silica measurement, including control of exposure, diagnosis, treatment and medical surveillance of silica-related diseases. This expertise is sought by international and national organizations to address the problems in developed and developing countries, where occupational silicosis is believed to be widespread.

For many exposed workers, prevention measures are non-existent. China recorded more than 500,000 cases of silicosis from 1991- 1995. In Brazil, more than 4,500 workers with silicosis have been cumulatively reported in the state of Minas Gerais. In India alone, millions of workers are at risk. In 1995, the World Health Organization (WHO) and the International Labour Organization (ILO) began a campaign to eliminate silicosis from the world by 2030. In 2005, WHO and its regional office, the Pan American Health Organization (PAHO), ILO, and the Chilean Health Ministry (MOH) requested that NIOSH provide technical assistance to build adequate capacity to eliminate silicosis in the Americas. In response to this request, NIOSH initiated a program called the “Americas Silicosis Initiative” in partnership with WHO, PAHO, and ILO. It is the first regional approach to silicosis and is based upon the sharing of expertise to benefit many countries. Substantial work was accomplished in Chile in 2006 and is underway in 2007 in Chile, Brazil, and Peru, including:

    • Training of physicians from Chile, Brazil, and Peru by US, Chilean and Brazilian experts
    • Development of a silica laboratory at the ISP in Santiago (including training for laboratory technicians from Chile, Brazil, Peru and Uruguay)
    • Training of workshop participants from Chile, Peru, Brazil and Uruguay in methods of dust control
    • Development of simple guidance for employers to put controls in place
    • Provision of field visits to small quarries and stone crushing and stone craft worksites to develop customized guidance sheets

The impact of NIOSH’s technical assistance was seen in July 2007, when Chilean Ministries of Health and Labor jointly hosted representatives of the Ministries of Brazil, Argentina, Uruguay, Mexico and Peru for a regional planning meeting that brought these countries into the Americas’ partnership.

The Americas Silicosis Initiative includes a cost-effective, novel educational approach called “Control Banding” to control exposures to the hazardous crystalline silica dust. NIOSH’s technical assistance to partners in Brazil, Chile, and Peru enables these countries to develop their own capacity to implement National Plans to eliminate silicosis. This partnership is a model for other countries and is helping to meet the ILO/WHO goal to eliminate silicosis by 2030. Global collaboration in silicosis benefits NIOSH in its effort to reach small business in the United States though experience and lessons learned in applying simple guidance to control silica exposures in small enterprises with partner countries in the Americas. At least 1.7 million United States’ workers are potentially exposed to respirable crystalline silica in a variety of industries and occupations, including mining and construction, and many are exposed to concentrations that exceed limits defined by current regulations and standards. OSHA is currently working on new regulations and NIOSH is developing new forms of simple guidance for employers and workers.

In October, a NIOSH technical expert visited Chile in to present the United States’ experience in controlling silicosis with the use of respirators in the workplace at the “Breath Safely” seminar. He met with the Chilean ISP on silica control topics related to respiratory protection, and proposed a joint project on developing respiratory protection programs for small and medium business enterprises. Prevention activities with the cooperation of government, labor, and industry are ongoing, and are the keys to silicosis elimination.