Ann. Occup. Hyg., 2014, Vol. 58, No. 1, 2–5 doi:10.1093/annhyg/met073 Advance Access publication 26 December 2013
E d i to r i a l
Monumental Hazards was the fact that 14 and 19% of the data were more than three times the OEL in these two sectors. In a recent detailed analysis of over 1400 samples representing 27 different construction industry tasks, Sauvé et al. (2013) found a median geometric mean of 0.05 mg m–3. Of the 27 tasks analyzed, 12 had geometric mean exposures exceeding 0.1 mg m–3. Thus, the frequent high exposures observed by Healy et al. are completely consistent with those observed in high silica use operations in both the USA and European Union (EU). These levels appear to persist despite the demonstrated effectiveness of typical dust control techniques. For instance, application of tool-mounted local exhaust ventilation is reported to reduce exposures by 70–98% (Croteau et al., 2002), and application of water-fed tools by 80–94% (Akbar-Khanzadeh et al., 2010). Almost the same level of control, a 69 and 71% decrease for local exhaust ventilation (LEV) and water controls, respectively, was observed in the realworld construction database modeled by Sauvé et al. (2013). The study by Healy et al. also identifies some of the challenges faced by managers and workers in effective control in many different contexts. Typical occupational hygiene dust control strategies include substitution with a less hazardous substance, the application of water at the point of operation, LEV with adequate capture and positioned correctly to capture emissions, and respiratory protective equipment selected, fitted, and used conscientiously. Among the stone cutters and masons observed by Healy, substitution could not be implemented because the historical integrity of the objects required the use of historically accurate
© The Author 2013. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.
2 •
Downloaded from http://annhyg.oxfordjournals.org/ at Australian National University on March 13, 2015
As we greet the New Year and the 58th volume of the Annals of Occupational Hygiene, we are reminded that some of our most ancient challenges remain with us today. In this issue, Dr Healy and colleagues present evidence of high levels of exposure to respirable crystalline silica (RCS) among workers maintaining and restoring castles, monuments, and other antiquities in Ireland (Healy et al., 2013). Workers cutting or grinding granite or sandstone had exposures exceeding the Irish occupational exposure limit (OEL) value of 0.1 mg m–3 30 or 57% of the time, respectively. The highest 8-h time-weighted average reached a breathtaking 6 mg m–3. The remarkable thing about this finding is that it is neither new nor unusual. Respiratory conditions associated with stone masons were described as early as the beginning of the 18th century (Ramazzini, 1940), and the specific etiology and pathology of silicosis, as a distinct disease caused by quartz exposure, have been understood since around the turn of the last century (Rosner and Markowitz, 1991). The link between silica and lung cancer was identified by about 1980 (Goldsmith et al., 1982) and has been authoritatively established since then (IARC, 2012). The levels of exposure observed by Dr Healy are also commonly seen in other sectors in which silica-containing materials are used. Almost 30% of full-shift RCS measurements obtained during inspections by US OSHA were over 0.1 mg m–3 (Yassin et al., 2005), and in OSHA’s own review of data from inspections in 2003–2009, 25 and 30% of the samples were over the current OEL in construction and all other industries, respectively (OSHA, 2013a). Even more impressive in the OSHA analysis
Monumental Hazards • 3
(NEPSI, 2013). Evidence for a positive effect of NEPSI in reducing silica exposures is now needed. In the USA, despite the NIOSH recommendation as early as 1974 to control silica to a level of 0.05 mg m–3 (NIOSH, 1974) and a notice of intent to regulate by OSHA in the same year, and the promulgation of a OEL of 0.1 mg m–3 in 1989 (which was subsequently vacated by the courts), the current regulation in the USA is still the antiquated permissible exposure limit (PEL) of [10/(%SiO2 + 2) mg m–3] (OSHA, 2013b). However, on 12 September 2013, OSHA published a ‘Notice of Proposed Rulemaking’ with the intent to promulgate a comprehensive standard on crystalline silica for the first time in the USA (OSHA, 2013a). The proposed rule includes a PEL of 0.05 mg m–3 and requirements for exposure assessment, health surveillance, and a set of control options for specific operations in construction in which control by only engineering means could prove infeasible. The proposal, if fully promulgated, would substantially change the policy landscape for silica control in the USA and provide an opportunity to stimulate the sorts of labour-management and across-industry collaborations that have taken root in the EU. In Europe, the EU is also in the process of considering an update to the Carcinogens and Mutagens Directive, which includes a discussion about introducing a binding OEL for crystalline silica. The socioeconomic and health impact assessment undertaken to support the discussions within Europe showed that, in monetary terms, the health benefits of introducing an OEL would outweigh the costs of compliance, regardless of the level at which the limits was set, i.e. at 0.05, 0.1, or 0.2 mg m–3 (Cherrie et al., 2011). Thus, in both the USA and the EU, the establishment of an enforceable OEL is under consideration and would provide a powerful stimulus for controlling exposure and supporting an adjusted social norm of silica control. However, it is also clear that establishment of a health-based OEL is only part of the answer. In a detailed analysis of the projected burden of lung cancer due to RCS exposure (and other carcinogens) in the UK, increasing the rate of compliance with the current silica OEL to 90% was predicted to prevent substantially more disease than lowering the OEL without changing the rate of compliance (Hutchings et al., 2012).
Downloaded from http://annhyg.oxfordjournals.org/ at Australian National University on March 13, 2015
materials. The engineering and protective equipment controls were available in the workshops but not adequately functional or effectively used. Thus, although technical solutions to the problem are well known, their implementation and use over time remain an elusive goal in many workplaces. A particularly striking example of control failure is presented by Radnoff, also in this issue (Radnoff and Kutz, 2014). Substitution of non-hazardous materials for a recognized hazard is among the most effective approaches in the hygienist’s ‘hierarchy of controls’ and should thus be a fool-proof technique where practicable. Thus, the results of Radnoff ’s exposure assessment among abrasive blasters in Ontario workshops using non-silica abrasives are particularly disturbing. RCS exposures were over the OEL (0.1 mg m–3) a majority of the time and were only slightly lower than those in workshops using silica sand. Apparently, the substitute ‘silica-free’ materials were not as silica free as indicated. Clearly, the availability of control technologies is only part of the equation for reducing risk. The technologies have to be implemented with sustained managerial and behavioural commitment and supported by effective social policy. Here, there is evidence of progress. In the EU, the Industrial Minerals Association has mounted a concerted effort to monitor respirable dust in the workplace since about 2000, allowing participating companies to receive regular reports on their own exposure levels, identify areas of high risk, and motivate actions to control these exposures (IMA-Europe). Analyses of the results of this program presented at this year’s Inhaled Particles symposium showed that overall there had been a 2- to 3-fold reduction of exposure concentrations since the start of the project (Kromhout et al., 2013), providing support for the concept that exposure monitoring with feedback to the affected worksites helps to support control measures. Another EU-wide agreement on the control of silica dust in the workplace, called NEPSI, provides the organizational context for labour-management cooperation on the surveillance of silica risk and control approaches across industries. The agreement requires signatories to monitor airborne dust and health, provides for central collection of exposure data and work practice information, and contains an extensive guidance document on methods of controlling silica in many component processes
4 • Monumental Hazards
Acknowledgements
The author would like to acknowledge the valuable insights and contributions of Annals Board member John Cherrie to the ideas presented here. Noah S. Seixas DEOHS, University of Washington, 4225 Roosevelt Way NE, Seattle, WA 98105, USA Tel: +1-206-685-7189; fax: +1-206-616-6240; e-mail: [email protected] References Akbar-Khanzadeh F, Milz SA, Wagner CD et al. (2010) Effectiveness of dust control methods for crystalline silica and respirable suspended particulate matter exposure during manual concrete surface grinding. J Occup Environ Hyg; 7: 700–11. Cherrie J, Gorman NM, Shafrir A et al. (2011) Health, socio-economic and environmental aspects of possible amendments to the EU Directive on the protection of workers from the risks related to exposure to carcinogens and mutagens at work. Luxembourg, EU: DG Employment. IOM Research Report P937/99. Available at http://europa.eu/ey2012/main.jsp?ca tId=716&langId=en&moreDocuments=yes Croteau GA, Guffey SE, Flanagan ME et al. (2002) The effect of local exhaust ventilation controls on dust exposures during concrete cutting and grinding activities. AIHA J (Fairfax, Va); 63: 458–67. Esswein EJ, Breitenstein M, Snawder J et al. (2013) Occupational exposures to respirable crystalline silica during hydraulic fracturing. J Occup Environ Hyg; 10: 347–56. Goldsmith DF, Guidotti TL, Johnston DR. (1982) Does occupational exposure to silica cause lung cancer? Am J Ind Med; 3: 423–40. Healy CB, Coggins MA, Van Tongeren M et al. (2013) Determinants of respirable crystalline silica exposure among stoneworkers involved in stone restoration work. Ann Occup Hyg; 58. Hutchings S, Cherrie JW, Van Tongeren M et al. (2012) Intervening to reduce the future burden of occupational cancer in britain: what could work? Cancer Prev Res (Phila); 5: 1213–22. IARC. (2012) A review of human carcinogens: arsenic, metals, fibres and dusts. In Monographs on the evaluation of carcinogic risks to humans. International Agency for Research on Cancer. Geneva, Switzerland, pp. 355–405. IMA-Europe. (2013) Dust monitoring programme. Available at http://ima-europe.eu/commitments/dust-monitoringprogramme. Accessed 7 November 2013. Kromhout H, Vlaanderen J, Houba R. (2013) Trends in exposure to respirable dust and quartz over a 12-year period in
Downloaded from http://annhyg.oxfordjournals.org/ at Australian National University on March 13, 2015
The apparent progress in the reduction of silica exposure through both regulatory advancements and concerted voluntary inter- and intra-industry cooperation is encouraging. However, it is also apparent that changes in the economic or political picture can reverse the positive trends. For instance, after a long-term decline in the incidence of pneumoconiosis among Appalachian coal miners, a sharp upswing in the number of severe cases of PMF, likely due to silica exposures, has been seen (Laney et al., 2010). The cases are primarily among miners in small, ‘low seam’ mines, in which high levels of silica exposure are present, and enforcement of coal dust and silica standards have been weak. In the European industrial minerals industry, after substantial progress in reducing silica exposure levels, the downward trend has flattened, and perhaps even seen a small increase in the percent of locations with over-exposures. (Kromhout et al., 2013). Although the exact cause of the deviation in the downward trend is not known, the authors speculate that the economic downturn since 2008, resulting in cutbacks in workforce, equipment maintenance, and delayed investments, may have contributed. Old hazards may also emerge within new technologies. The recent development of hydraulic fracturing or ‘fracking,’ in the USA as a means of extracting natural gas from shale deposits has resulted in a new source of over-exposure to silica. In an initial investigation of silica exposures at 11 fracking sites, almost 80% of the samples exceeded the NIOSH recommended exposure limit of 0.05 mg m–3, with over 30% exceeding this value by more than 10-fold (Esswein et al., 2013). Materials containing crystalline silica have long been a part of human existence, being worked for shelter and monuments that were intended to last for a long time. The unintended consequences of these technologies in disease and death associated with airborne silica-containing dusts have similarly been with us for a long time. Despite great strides in controlling silica dust exposure at work, many situations remain in which our understanding of the disease, and our technology for controlling exposures, are inadequately implemented. Continuing to improve policies and programs that support the full implementation of controls is required to make silica-induced disease a thing of the past. Then, those who have led the effort for so long will deserve a monument of their own.
Monumental Hazards • 5 OSHA. (2013b) Occupational exposure to respirable crystalline silica: proposed rule, U.S. Departmentof Labor, Washington, DC. Fed Reg; 78: 56274–504. Available at https://www. federalregister.gov/articles/2013/09/12/2013–20997/ occupational-exposure-to-respirable-crystalline-silica. Accessed 7 November 2013. Radnoff D, Kutz M. (2014) Exposure to crystalline silica in abrasive blasting operations where silica and non-silica abrasives are used. Ann Occ Hyg; 58. Ramazzini B. (1940) Diseases of workers (De Morbis Artificum). Chicago, IL: The University of Chicago Press. Rosner D, Markowitz S. (1991) Deadly dust, silicosis and the politics of occupational disease in twentieth-century America. Princeton, NJ: Princeton University Press. Sauvé JF, Beaudry C, Bégin D et al. (2013) Silica exposure during construction activities: statistical modeling of taskbased measurements from the literature. Ann Occup Hyg; 57: 432–43. Yassin A, Yebesi F, Tingle R. (2005) Occupational exposure to crystalline silica dust in the United States, 1988-2003. Environ Health Perspect; 113: 255–60.
Downloaded from http://annhyg.oxfordjournals.org/ at Australian National University on March 13, 2015
the industrial minerals industry. Nottingham, UK: Inhaled Particles XI. Available at http://www.inhaledparticles.org. uk/files/2013/08/H-Kromhout-Presentation-Session-7. pdf. Accessed 7 November 2013. Laney AS, Petsonk EL, Attfield MD. (2010) Pneumoconiosis among underground bituminous coal miners in the United States: is silicosis becoming more frequent? Occup Environ Med; 67: 652–6. NEPSI. (2013) The European network on silica: good practices guide. Available at http://www.nepsi.eu/agreement-goodpractice-guide/agreement.aspx. Accessed 7 November 2013. NIOSH. (1974) Criteria for a recommended standard: occupational Exposure to Cristalline Silica, DHHS (NIOSH). OSHA. (2013a) Code of Federal regulations, occupational safety and health standards. toxic and hazardous substances, mineral dusts. Washington, DC: US Department of Labor, Occupational Safety and Health Administration. 1910.1000, Table Z-3. Available at https://www.osha.gov/pls/oshaweb/ owadisp.show_document?p_table=STANDARDS&p_ id=9994. Accessed 7 November 2013.
E d i to r i a l
Monumental Hazards was the fact that 14 and 19% of the data were more than three times the OEL in these two sectors. In a recent detailed analysis of over 1400 samples representing 27 different construction industry tasks, Sauvé et al. (2013) found a median geometric mean of 0.05 mg m–3. Of the 27 tasks analyzed, 12 had geometric mean exposures exceeding 0.1 mg m–3. Thus, the frequent high exposures observed by Healy et al. are completely consistent with those observed in high silica use operations in both the USA and European Union (EU). These levels appear to persist despite the demonstrated effectiveness of typical dust control techniques. For instance, application of tool-mounted local exhaust ventilation is reported to reduce exposures by 70–98% (Croteau et al., 2002), and application of water-fed tools by 80–94% (Akbar-Khanzadeh et al., 2010). Almost the same level of control, a 69 and 71% decrease for local exhaust ventilation (LEV) and water controls, respectively, was observed in the realworld construction database modeled by Sauvé et al. (2013). The study by Healy et al. also identifies some of the challenges faced by managers and workers in effective control in many different contexts. Typical occupational hygiene dust control strategies include substitution with a less hazardous substance, the application of water at the point of operation, LEV with adequate capture and positioned correctly to capture emissions, and respiratory protective equipment selected, fitted, and used conscientiously. Among the stone cutters and masons observed by Healy, substitution could not be implemented because the historical integrity of the objects required the use of historically accurate
© The Author 2013. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.
2 •
Downloaded from http://annhyg.oxfordjournals.org/ at Australian National University on March 13, 2015
As we greet the New Year and the 58th volume of the Annals of Occupational Hygiene, we are reminded that some of our most ancient challenges remain with us today. In this issue, Dr Healy and colleagues present evidence of high levels of exposure to respirable crystalline silica (RCS) among workers maintaining and restoring castles, monuments, and other antiquities in Ireland (Healy et al., 2013). Workers cutting or grinding granite or sandstone had exposures exceeding the Irish occupational exposure limit (OEL) value of 0.1 mg m–3 30 or 57% of the time, respectively. The highest 8-h time-weighted average reached a breathtaking 6 mg m–3. The remarkable thing about this finding is that it is neither new nor unusual. Respiratory conditions associated with stone masons were described as early as the beginning of the 18th century (Ramazzini, 1940), and the specific etiology and pathology of silicosis, as a distinct disease caused by quartz exposure, have been understood since around the turn of the last century (Rosner and Markowitz, 1991). The link between silica and lung cancer was identified by about 1980 (Goldsmith et al., 1982) and has been authoritatively established since then (IARC, 2012). The levels of exposure observed by Dr Healy are also commonly seen in other sectors in which silica-containing materials are used. Almost 30% of full-shift RCS measurements obtained during inspections by US OSHA were over 0.1 mg m–3 (Yassin et al., 2005), and in OSHA’s own review of data from inspections in 2003–2009, 25 and 30% of the samples were over the current OEL in construction and all other industries, respectively (OSHA, 2013a). Even more impressive in the OSHA analysis
Monumental Hazards • 3
(NEPSI, 2013). Evidence for a positive effect of NEPSI in reducing silica exposures is now needed. In the USA, despite the NIOSH recommendation as early as 1974 to control silica to a level of 0.05 mg m–3 (NIOSH, 1974) and a notice of intent to regulate by OSHA in the same year, and the promulgation of a OEL of 0.1 mg m–3 in 1989 (which was subsequently vacated by the courts), the current regulation in the USA is still the antiquated permissible exposure limit (PEL) of [10/(%SiO2 + 2) mg m–3] (OSHA, 2013b). However, on 12 September 2013, OSHA published a ‘Notice of Proposed Rulemaking’ with the intent to promulgate a comprehensive standard on crystalline silica for the first time in the USA (OSHA, 2013a). The proposed rule includes a PEL of 0.05 mg m–3 and requirements for exposure assessment, health surveillance, and a set of control options for specific operations in construction in which control by only engineering means could prove infeasible. The proposal, if fully promulgated, would substantially change the policy landscape for silica control in the USA and provide an opportunity to stimulate the sorts of labour-management and across-industry collaborations that have taken root in the EU. In Europe, the EU is also in the process of considering an update to the Carcinogens and Mutagens Directive, which includes a discussion about introducing a binding OEL for crystalline silica. The socioeconomic and health impact assessment undertaken to support the discussions within Europe showed that, in monetary terms, the health benefits of introducing an OEL would outweigh the costs of compliance, regardless of the level at which the limits was set, i.e. at 0.05, 0.1, or 0.2 mg m–3 (Cherrie et al., 2011). Thus, in both the USA and the EU, the establishment of an enforceable OEL is under consideration and would provide a powerful stimulus for controlling exposure and supporting an adjusted social norm of silica control. However, it is also clear that establishment of a health-based OEL is only part of the answer. In a detailed analysis of the projected burden of lung cancer due to RCS exposure (and other carcinogens) in the UK, increasing the rate of compliance with the current silica OEL to 90% was predicted to prevent substantially more disease than lowering the OEL without changing the rate of compliance (Hutchings et al., 2012).
Downloaded from http://annhyg.oxfordjournals.org/ at Australian National University on March 13, 2015
materials. The engineering and protective equipment controls were available in the workshops but not adequately functional or effectively used. Thus, although technical solutions to the problem are well known, their implementation and use over time remain an elusive goal in many workplaces. A particularly striking example of control failure is presented by Radnoff, also in this issue (Radnoff and Kutz, 2014). Substitution of non-hazardous materials for a recognized hazard is among the most effective approaches in the hygienist’s ‘hierarchy of controls’ and should thus be a fool-proof technique where practicable. Thus, the results of Radnoff ’s exposure assessment among abrasive blasters in Ontario workshops using non-silica abrasives are particularly disturbing. RCS exposures were over the OEL (0.1 mg m–3) a majority of the time and were only slightly lower than those in workshops using silica sand. Apparently, the substitute ‘silica-free’ materials were not as silica free as indicated. Clearly, the availability of control technologies is only part of the equation for reducing risk. The technologies have to be implemented with sustained managerial and behavioural commitment and supported by effective social policy. Here, there is evidence of progress. In the EU, the Industrial Minerals Association has mounted a concerted effort to monitor respirable dust in the workplace since about 2000, allowing participating companies to receive regular reports on their own exposure levels, identify areas of high risk, and motivate actions to control these exposures (IMA-Europe). Analyses of the results of this program presented at this year’s Inhaled Particles symposium showed that overall there had been a 2- to 3-fold reduction of exposure concentrations since the start of the project (Kromhout et al., 2013), providing support for the concept that exposure monitoring with feedback to the affected worksites helps to support control measures. Another EU-wide agreement on the control of silica dust in the workplace, called NEPSI, provides the organizational context for labour-management cooperation on the surveillance of silica risk and control approaches across industries. The agreement requires signatories to monitor airborne dust and health, provides for central collection of exposure data and work practice information, and contains an extensive guidance document on methods of controlling silica in many component processes
4 • Monumental Hazards
Acknowledgements
The author would like to acknowledge the valuable insights and contributions of Annals Board member John Cherrie to the ideas presented here. Noah S. Seixas DEOHS, University of Washington, 4225 Roosevelt Way NE, Seattle, WA 98105, USA Tel: +1-206-685-7189; fax: +1-206-616-6240; e-mail: [email protected] References Akbar-Khanzadeh F, Milz SA, Wagner CD et al. (2010) Effectiveness of dust control methods for crystalline silica and respirable suspended particulate matter exposure during manual concrete surface grinding. J Occup Environ Hyg; 7: 700–11. Cherrie J, Gorman NM, Shafrir A et al. (2011) Health, socio-economic and environmental aspects of possible amendments to the EU Directive on the protection of workers from the risks related to exposure to carcinogens and mutagens at work. Luxembourg, EU: DG Employment. IOM Research Report P937/99. Available at http://europa.eu/ey2012/main.jsp?ca tId=716&langId=en&moreDocuments=yes Croteau GA, Guffey SE, Flanagan ME et al. (2002) The effect of local exhaust ventilation controls on dust exposures during concrete cutting and grinding activities. AIHA J (Fairfax, Va); 63: 458–67. Esswein EJ, Breitenstein M, Snawder J et al. (2013) Occupational exposures to respirable crystalline silica during hydraulic fracturing. J Occup Environ Hyg; 10: 347–56. Goldsmith DF, Guidotti TL, Johnston DR. (1982) Does occupational exposure to silica cause lung cancer? Am J Ind Med; 3: 423–40. Healy CB, Coggins MA, Van Tongeren M et al. (2013) Determinants of respirable crystalline silica exposure among stoneworkers involved in stone restoration work. Ann Occup Hyg; 58. Hutchings S, Cherrie JW, Van Tongeren M et al. (2012) Intervening to reduce the future burden of occupational cancer in britain: what could work? Cancer Prev Res (Phila); 5: 1213–22. IARC. (2012) A review of human carcinogens: arsenic, metals, fibres and dusts. In Monographs on the evaluation of carcinogic risks to humans. International Agency for Research on Cancer. Geneva, Switzerland, pp. 355–405. IMA-Europe. (2013) Dust monitoring programme. Available at http://ima-europe.eu/commitments/dust-monitoringprogramme. Accessed 7 November 2013. Kromhout H, Vlaanderen J, Houba R. (2013) Trends in exposure to respirable dust and quartz over a 12-year period in
Downloaded from http://annhyg.oxfordjournals.org/ at Australian National University on March 13, 2015
The apparent progress in the reduction of silica exposure through both regulatory advancements and concerted voluntary inter- and intra-industry cooperation is encouraging. However, it is also apparent that changes in the economic or political picture can reverse the positive trends. For instance, after a long-term decline in the incidence of pneumoconiosis among Appalachian coal miners, a sharp upswing in the number of severe cases of PMF, likely due to silica exposures, has been seen (Laney et al., 2010). The cases are primarily among miners in small, ‘low seam’ mines, in which high levels of silica exposure are present, and enforcement of coal dust and silica standards have been weak. In the European industrial minerals industry, after substantial progress in reducing silica exposure levels, the downward trend has flattened, and perhaps even seen a small increase in the percent of locations with over-exposures. (Kromhout et al., 2013). Although the exact cause of the deviation in the downward trend is not known, the authors speculate that the economic downturn since 2008, resulting in cutbacks in workforce, equipment maintenance, and delayed investments, may have contributed. Old hazards may also emerge within new technologies. The recent development of hydraulic fracturing or ‘fracking,’ in the USA as a means of extracting natural gas from shale deposits has resulted in a new source of over-exposure to silica. In an initial investigation of silica exposures at 11 fracking sites, almost 80% of the samples exceeded the NIOSH recommended exposure limit of 0.05 mg m–3, with over 30% exceeding this value by more than 10-fold (Esswein et al., 2013). Materials containing crystalline silica have long been a part of human existence, being worked for shelter and monuments that were intended to last for a long time. The unintended consequences of these technologies in disease and death associated with airborne silica-containing dusts have similarly been with us for a long time. Despite great strides in controlling silica dust exposure at work, many situations remain in which our understanding of the disease, and our technology for controlling exposures, are inadequately implemented. Continuing to improve policies and programs that support the full implementation of controls is required to make silica-induced disease a thing of the past. Then, those who have led the effort for so long will deserve a monument of their own.
Monumental Hazards • 5 OSHA. (2013b) Occupational exposure to respirable crystalline silica: proposed rule, U.S. Departmentof Labor, Washington, DC. Fed Reg; 78: 56274–504. Available at https://www. federalregister.gov/articles/2013/09/12/2013–20997/ occupational-exposure-to-respirable-crystalline-silica. Accessed 7 November 2013. Radnoff D, Kutz M. (2014) Exposure to crystalline silica in abrasive blasting operations where silica and non-silica abrasives are used. Ann Occ Hyg; 58. Ramazzini B. (1940) Diseases of workers (De Morbis Artificum). Chicago, IL: The University of Chicago Press. Rosner D, Markowitz S. (1991) Deadly dust, silicosis and the politics of occupational disease in twentieth-century America. Princeton, NJ: Princeton University Press. Sauvé JF, Beaudry C, Bégin D et al. (2013) Silica exposure during construction activities: statistical modeling of taskbased measurements from the literature. Ann Occup Hyg; 57: 432–43. Yassin A, Yebesi F, Tingle R. (2005) Occupational exposure to crystalline silica dust in the United States, 1988-2003. Environ Health Perspect; 113: 255–60.
Downloaded from http://annhyg.oxfordjournals.org/ at Australian National University on March 13, 2015
the industrial minerals industry. Nottingham, UK: Inhaled Particles XI. Available at http://www.inhaledparticles.org. uk/files/2013/08/H-Kromhout-Presentation-Session-7. pdf. Accessed 7 November 2013. Laney AS, Petsonk EL, Attfield MD. (2010) Pneumoconiosis among underground bituminous coal miners in the United States: is silicosis becoming more frequent? Occup Environ Med; 67: 652–6. NEPSI. (2013) The European network on silica: good practices guide. Available at http://www.nepsi.eu/agreement-goodpractice-guide/agreement.aspx. Accessed 7 November 2013. NIOSH. (1974) Criteria for a recommended standard: occupational Exposure to Cristalline Silica, DHHS (NIOSH). OSHA. (2013a) Code of Federal regulations, occupational safety and health standards. toxic and hazardous substances, mineral dusts. Washington, DC: US Department of Labor, Occupational Safety and Health Administration. 1910.1000, Table Z-3. Available at https://www.osha.gov/pls/oshaweb/ owadisp.show_document?p_table=STANDARDS&p_ id=9994. Accessed 7 November 2013.
