Revista Peruana de Medicina Experimental y Salud Publica
versión impresa ISSN 1726-4634
CARLIN, César E. Características de la Silicosis en las minas del Perú: Estudio epidemiológico preliminar. Rev. perú. med. exp. salud publica [online]. 1957, vol.11, n.1-2, pp. 1-27. ISSN 1726-4634.
The following conclusions are presented as a result of an epidemiological study on Silicosis, found in 22 mining centers: Every effort should be taken in order to prevent the risk of acquiring Silicosis in a mine where quartz is present in the atmospheric dust. The Institute of Occupational Health employs the epidemiological method to determine the reasons for illness and the effects of risks involved in an industry. This method permits an explanation of the role played by each one of the factors: agent, host and environment, that causes alteration of health, and to detect places of risk and to develop pertinent recommendations in order to protect the health of the miners. The epidemiological study of Silicosis included: an analysis of the environmental conditions of the miners, and characteristics of the causal agent, such as: amount of quartz in atmospheric dust, dust concentration, particle size; and medical characteristics of the miners examined simultancously. This study included the following: 240 determinations of quartz content, 4,661 particle counting, 46,100 measurements of particle size and examination of 11,684 miners employed in underground and surface activities (during 10 years in 22 mining centers) . As results of correlation of the causal factors and that of the individual (or host), all working under similar environmental conditions, the following rates were observed. 1. Mines grouped according to the free silica content in the atmosphere: a) Those with less than 5 per cent of free silica in dust and 6.9 m.p.p.c.f.a. : values of 2.4 and 30.9 per thousand in miners with less than 5 and between 5-14.9 years of mine work respectively. b) Mines with free silica content between 5-49 per cent and 6.5 m.p.p.c.f.a. : values of 11.6, 81.6 and 144. 4 per thousand in miners with less than five years, between 5-14.9 years and more than 15 years of mine work respectively. c) Mines with more than 50 per cent of free silica and 4.8 m.p.p.c.f.a.: values of 30.7, 48.3 and 76.9 per thousand in miners with less than five years, between 5 - 14.9 years and more than 15 years of mine work respectively. 2. Mines grouped according to their, dust concentration in m.p.p.c.f.a.: a) For those with less than 5 m.p.p.c.f.a. and 27.7 per cent free silica: silicosis values of 9.3, 61.5 and 129.7 per thousand in miners with less than five years, between 5-14.9 years, and more than 15 years of mine work respectively. b) Mines with dust concentration between 5-19.9 m.p.p.c.f.a. and 28.8 per cent of free silica: values of 18.3 and 98.2 and 154.9 per thousand in miners with less than five years, between 5 - 14.9 years, and more than 15 years of work respectively. c) Mines with dust concentration greater than 20.0 m.p.p.c.f.a. and 6.7 per cent of free silica silicosis values of 3.5, 50.3 and 101 .7 per thousand in miners wíth less than five years, between 5 - 14.9 years, and more than 15 years of mine work respectively. It was found that 94 (1.3%) persons, out of 7,306 who were examined had silicosis; they belonged to,the group of 0 - 4 years. One of these showed evidence of first degree silicosis which he had acquired in only seven months and 18 days, of verified exposure time. He was 20 years old and worked in a gold mine where the atmospheric conditions were extremely bad and the causal agent concentration, and content of quartz, very high. Similarly, two more cases of Silicosis were found to have developed in the short time of 13 and 16 months of mine work. They were brothers, one 20 years old and the other was 28. Both of them had worked in the same mine where the quartz content in the atmospheric dust was 50 per cent. When mentioning the characteristics of the environmental factors and of the agent, it is also very important to consider the individual factor in the presentation, frequency, and distribution of the illness.