Silicosis in Brazilian pit diggers: relationship between dust exposure and radiologic findings

Mortality from silicosis in Brazil: Temporal trends in the period 1980-2017

BACKGROUND

Silicosis is the most prevalent pneumoconiosis in Brazil. We aimed to estimate mortality rates and temporal trends for silicosis, and to identify areas of highest mortality.

METHODS

Records of silicosis as the underlying (1980-2017) or contributory (2000-2017) cause of death in adults aged 20 years and older were retrieved from the Brazilian Mortality Database. Age-standardized mortality rates (ASMR) were calculated. The annual trend in ASMR was analyzed by joinpoint regression. Mortality rates per 100,000 person-years were calculated for each municipality. We analyzed temporal trends in municipalities where similar activities with exposure to silica were performed.

RESULTS

There were 3164 death records (96.6% men) distributed over 14% of the municipalities. Mean age of death was 59.2 (SD 15.1) and mean ASMR was 0.085/100,000 (confidence interval 0.080-0.091). Joinpoint regression showed a significant increase in ASMR from 1980 to 2006 and a significant decrease after 2006 driven by a decline in deaths of individuals younger than 70 years. The highest mortality rate was 21.83/100,000 person-years, in a municipality with small mining operations for gems. Gold mining municipalities showed the highest composite death rate, 4.0/100,000 person-years. Tuberculosis was the main cause of death when silicosis was a contributing cause.

CONCLUSIONS

In contrast with developed countries, silicosis mortality in Brazil increased to 2006 and subsequently started to drop, mostly from a plateau or decrease in deaths occurring in municipalities which regulated economic activities. However, this decrease did not occur in the older age group nor in the unregulated sector, the latter being the main challenge for exposure control and surveillance.

Cell-Based Therapy for Silicosis

Silicosis is the most common pneumoconiosis globally, with higher prevalence and incidence in developing countries. To date, there is no effective treatment to halt or reverse the disease progression caused by silica-induced lung injury. Significant advances have to be made in order to reduce morbidity and mortality related to silicosis. In this review, we have highlighted the main mechanisms of action that cause lung damage by silica particles and summarized the data concerning the therapeutic promise of cell-based therapy for silicosis.

[Well-digger's lung in Mali during the decade of 2001-2010]

INTRODUCTION

The well-digger is a craftsman who hollows wells often manually; this trade can be source of inhalation of the particles of silica. The whole of the radio clinical signs linked to this profession is known under the term "Well-digger's lung". The goal was to study the radio clinical aspects and progression in black African's pulmonological environment.

METHODS

Retrospective and descriptive study concerning the respiratory involvement of well-diggers in the Pulmonology service of the Teaching Hospital of Bamako, from January 2001 to December 2010. The admission registers were used as data verification support.

RESULTS

Among 4158 admissions for lung affection, we have collected 39 cases of well-digger's lung (0.9%), all young male adults. The average of exposition period was 13 ± 9 years, correlated to the patient's age (p<0.001). The principal reason of consultation was dyspnea (94.8%). The complications were frequent (cardiac, infectious, pleural). The radiological pictures were made of bilateral big opacities associated with small opacities. The evolution was unfavorable in the majority of the cases.

CONCLUSION

The well-digger's lung is a young adult pneumoconiosis linked to the inhalation of the particles of silica during the trade (profession) of well-digger that complicates frequently in chronic respiratory insufficiency.

[Silicosis among former copper mine workers]

There is a dearth of Brazilian studies analyzing the effect of ongoing exposure to silica among former copper mine workers, as radiographic readings for silicosis have received widespread medical attention. The scope of this study is to investigate the clinical and radiological manifestations of silicosis among former copper mine workers. A sample of 100 former copper miners had their clinical and occupational histories recorded and underwent chest radiography in a cross-sectional study that included personal interviews in which their age, sex and time worked in copper extraction were recorded. Patients with recent chest X-Rays brought them with them, or they signed a term of consent and X-Rays were taken and analyzed by the radiologist using the Student t Test and Pearson test. Among the 100 miners, 35% had silicosis, 11% had conditions other than silicosis, such as tuberculosis, emphysema, chronic pulmonary obstructive disease, and 54% had no pulmonary lesions. The high incidence of silicosis reinforces the recommendation that exposure should be halted as soon as an X-ray detects the condition.

Exposição ocupacional à sílica no Brasil no ano de 2001

OBJETIVO: Estimar o número de trabalhadores brasileiros expostos à sílica no ano de 2001. MÉTODO: Informações sobre ocupações e setores econômicos foram reunidas em uma matriz de exposição ocupacional (MEO) com 347 categorias ocupacionais por 25 subsetores econômicos. Informações sobre o número de trabalhadores por ocupação foram extraídas da base de dados Relatório Anual de Informações Sociais (RAIS) do Ministério do Trabalho e Emprego. A exposição à sílica foi avaliada e classificada por dois peritos em quatro categorias, de acordo com a freqüência semanal de exposição no ambiente de trabalho. RESULTADOS: Foram considerados não expostos 31.451.594 trabalhadores (85,7%), possivelmente expostos 976.939 (2,65%), provavelmente expostos 2.404.955 (6,52%) e definitivamente expostos à sílica 2.065.929 (5,6%). Os setores com a maior prevalência de exposição foram: construção civil 65%, extração de pedras 59%, indústria de mineral não metálico 55% e indústria metalúrgica 24%. No setor de serviços de terceiros, a prevalência foi de 2%. CONCLUSÃO: A prevalência de trabalhadores brasileiros definitivamente expostos à sílica é mais alta do que aquela observada em países europeus, onde estudos semelhantes foram conduzidos.

[Silicosis]

This chapter presents a review of the national and international literature on the subject of silicosis. Epidemiological, pathological, diagnostic and pulmonary function aspects are discussed. The clinical classification and methods of treating silicosis are reviewed, as are other silicarelated diseases such as tuberculosis, lung cancer and scleroderma. Prevention and medical-legal aspects are also discussed.

Estudo das internações hospitalares por pneumoconioses no Brasil, 1984-2003

INTRODUÇÃO: pneumoconiose reúne um conjunto de doenças respiratórias conhecidas pelo agente principal causador, como silicose, asbestose, talcose, beriliose e outras. A incidência, possivelmente, deve ser elevada entre os expostos, mas não há informações epidemiológicas referentes a séries históricas sobre as internações hospitalares nas diversas regiões do país. OBJETIVO: analisar as internações hospitalares por pneumoconiose no período entre 1984 e 2003 em todo o território nacional. CASUÍSTICA E MÉTODO: informações de morbidade foram recolhidas, descritas e analisadas a partir do Sistema de Internação por AIH do DATASUS, Centro Nacional de Epidemiologia do Ministério da Saúde, período de 1984 a 2003, englobando todas as regiões do Brasil e seus Estados. Foram utilizadas listas do CID-9 (1984-1997) e CID-10 (1998-2003). RESULTADOS: o Brasil apresentou entre 1984 e 1991 taxas elevadas de internações em todas as regiões, com tendência de crescimento e uma posterior redução após esta data. A mediana das internações para o período entre 1984 e 1991 foi maior na região Centro-Oeste e menor na região Norte. No segundo período, entre 1992 e 2003, verificou-se uma modificação com uma menor mediana na região Nordeste e maior na região Sul. DISCUSSÃO: A diferença encontrada entre os dois períodos pode ser explicada pelos critérios diagnósticos utilizados nestes períodos e a forma como era coletada a informação. As diferenças entre as regiões provavelmente refletem os processos de trabalhos locais e o acesso dos trabalhadores aos serviços de saúde. CONCLUSÃO: Os dados mostram que são necessárias ações de controle e prevenção dessas doenças no ambiente de trabalho. As pneumoconioses são um problema importante de Saúde Pública, onde os números ainda não refletem adequadamente o problema. Certamente os coeficientes se forem calculados sobre a população efetivamente exposta revelarão doenças de elevadas morbidade.