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Occup Environ Med. 2004 October; 61(10): 811–816.
PMCID: PMC1740677

Silicosis prevalence and exposure-response relations in South African goldminers

Abstract

Aims: To measure the prevalence of silicosis among black migrant contract workers on a South African goldmine and to investigate exposure-response relations with silica dust.

Methods: In a cross sectional study, 520 black goldminers (aged >37 years) were interviewed and had chest radiographs taken. Silicosis was defined as International Labour Organisation Classification radiological profusion of 1/1 or greater.

Results: Mean length of service was 21.8 years (range 6.3–34.5). The mean intensity of respirable dust exposure was 0.37 mg/m3 (range 0–0.70) and of quartz 0.053 mg/m3 (range 0–0.095). The prevalence of silicosis was 18.3–19.9% depending on reader. Significant trends were found between the prevalence of silicosis and length of service, mean intensity of exposure, and cumulative exposure.

Conclusion: Results confirm a large burden of silicosis among older black workers in the South African goldmining industry, which is likely to worsen as such miners spend longer periods in continuous employment in dusty jobs. An urgent need for improved dust control in the industry is indicated. If the assumption of stability of average dust concentrations on this mine over the working life of this group of workers is correct, these workers developed silicosis while exposed to a quartz concentration below the recommended occupational exposure limit (OEL) of 0.1 mg/m3. This accords with a mounting body of evidence that an OEL of 0.1 mg/m3 is not protective against silicosis.

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Selected References

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  • Leger JP. Occupational diseases in South African mines--a neglected epidemic? S Afr Med J. 1992 Feb 15;81(4):197–201. [PubMed]
  • Trapido AS, Mqoqi NP, Williams BG, White NW, Solomon A, Goode RH, Macheke CM, Davies AJ, Panter C. Prevalence of occupational lung disease in a random sample of former mineworkers, Libode District, Eastern Cape Province, South Africa. Am J Ind Med. 1998 Oct;34(4):305–313. [PubMed]
  • Cowie RL, van Schalkwyk MG. The prevalence of silicosis in Orange Free State gold miners. J Occup Med. 1987 Jan;29(1):44–46. [PubMed]
  • Steen TW, Gyi KM, White NW, Gabosianelwe T, Ludick S, Mazonde GN, Mabongo N, Ncube M, Monare N, Ehrlich R, et al. Prevalence of occupational lung disease among Botswana men formerly employed in the South African mining industry. Occup Environ Med. 1997 Jan;54(1):19–26. [PMC free article] [PubMed]
  • Ia Grange MA. Occupational lung diseases in ex-mineworkers. S Afr Med J. 1996 Jul;86(7):841–841. [PubMed]
  • White N. Occupational lung disease in ex-mineworkers--who answers the alarm? S Afr Med J. 1996 Sep;86(9):1127–1127. [PubMed]
  • Gibbs GW, Du Toit RSJ. Estimating the quartz exposure of South African gold miners. Ann Occup Hyg. 2002 Oct;46(7):597–607. [PubMed]
  • Murray J, Kielkowski D, Reid P. Occupational disease trends in black South African gold miners. An autopsy-based study. Am J Respir Crit Care Med. 1996 Feb;153(2):706–710. [PubMed]
  • Hnizdo E, Sluis-Cremer GK. Risk of silicosis in a cohort of white South African gold miners. Am J Ind Med. 1993 Oct;24(4):447–457. [PubMed]
  • Chen W, Zhuang Z, Attfield MD, Chen BT, Gao P, Harrison JC, Fu C, Chen JQ, Wallace WE. Exposure to silica and silicosis among tin miners in China: exposure-response analyses and risk assessment. Occup Environ Med. 2001 Jan;58(1):31–37. [PMC free article] [PubMed]
  • Corbett EL, Churchyard GJ, Clayton TC, Williams BG, Mulder D, Hayes RJ, De Cock KM. HIV infection and silicosis: the impact of two potent risk factors on the incidence of mycobacterial disease in South African miners. AIDS. 2000 Dec 1;14(17):2759–2768. [PubMed]
  • Sherson D. Silicosis in the twenty first century. Occup Environ Med. 2002 Nov;59(11):721–722. [PMC free article] [PubMed]
  • Greaves IA. Not-so-simple silicosis: a case for public health action. Am J Ind Med. 2000 Mar;37(3):245–251. [PubMed]

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