clay and Pneumoconiosis

The purpose of this study was to describe the clinical, chest radiographic, high-resolution CT, and histopathologic features of clay dye "sendo" dust pneumoconiosis in seven rush mat ("tatami") workers.. Seven patients with a history of occupational exposure to sendo dust and radiographic changes suggestive of pneumoconiosis were retrospectively reviewed.. The duration of exposure ranged from 15 to 45 years (median, 30 years). Three patients had cough, and four patients had abnormal pulmonary function test results. Chest radiographs showed nodular opacities < 3 mm in diameter (types p and q) in all patients. The standard International Labor Office profusion score ranged from 0/1 to 1/1 (median, 1/0). High-resolution CT demonstrated small nodular opacities (types p and q) in all seven patients. In four patients, high-resolution CT demonstrated branching centrilobular structures, airway ectasia, airway wall thickening, and emphysematous changes. None of the patients had conglomerate nodules, large opacities, honeycombing, pleural effusion, or lymphadenopathy. Microscopic examination of the specimens obtained by open lung biopsy or transbronchial lung biopsy revealed nodular fibrosis with accumulation of dust-laden macrophages, but no silicotic nodules. Needle-like particles of 1 to 20 microm in length were evident among the dust deposits, and birefringent crystals were identified under polarizing microscopy. Four of seven patients showed intra-alveolar fibroblastic foci similar to Masson bodies, accompanied by dust deposition.. Rush mat workers' sendo dust pneumoconiosis is caused by dust containing free silica. The radiographic and high-resolution CT findings consist of small nodular opacities < 3 mm in diameter and bronchial and bronchiolar abnormalities.

Topics: Aged; Aluminum Silicates; Biopsy, Needle; Chemical Industry; Clay; Dust; Female; Humans; Immunohistochemistry; Male; Middle Aged; Occupational Exposure; Pneumoconiosis; Probability; Prognosis; Radiography, Thoracic; Respiratory Function Tests; Retrospective Studies; Risk Assessment; Sampling Studies; Severity of Illness Index; Tomography, X-Ray Computed

To evaluate the effect of exposure to rush-mat dust on the health of workers.. A cross sectional study of 661 workers (349 men, 312 women) from 35 rush-mat plants was carried out by using occupational health investigation, questionnare and physical examination.. The geometric mean total dust concentration in the workshop was up to 20.00 mg/m3, and the geometric mean respirable dust concentration reached 8.22 mg/m3. The mean free SiO2 concentration of accumulated dust was 25.6%. The prevalence of radiographic small opacities profusion category > or = 1/0, according to the China Classification for pneumoconiosis (GB 5906-2000), and compared with the ILO 1980 system, was 2.57%. Even more, one man had category 2 pneumoconiosis with progressive massive fibrosis. However, the incidence of pneumoconiosis (1/0 at least) was correlated with work duration and dust concentration(r = 1.156, P < 0.001; r = 0.106, P = 0.006, respectively). Some positive correlations were found between the incidence of cough or expectoration and occupational exposure (r = 0.085, P = 0.028; r = 0.094, P = 0.016, respectively).. To our knowledge, this is the first report of rush pneumoconiosis in China. The results have offered the possibility of a dose-response relationship between rush-mat dust and pneumoconiosis. More investigation in this area is need.

Topics: Aluminum Silicates; Chemical Industry; Clay; Cross-Sectional Studies; Dust; Female; Humans; Male; Occupational Exposure; Pneumoconiosis

Dust exposure and pneumoconiosis were investigated in a South African pottery that manufactured wall tiles and bathroom fittings. This paper describes the objectives of the investigation and presents dust measurement data. x Ray diffraction showed that the clays used by the pottery had a high quartz content (range 58%-23%, mean 38%). Exposure to respirable dust was measured for 43 workers and was highest (6.6 mg/m3) in a bathroom fitting fettler. Quartz concentrations in excess of 0.1 mg/m3 were found in all sections of the manufacturing process from slip production to biscuit firing and sorting. The proportion of quartz in the respirable dust of these sections was 24% to 33%. This is higher than is usually reported in English potteries. Four hundred and six (80%) of the 509 workers employed at the pottery were potentially at risk of occupational lung disease. The finding of large numbers of pottery workers exposed to unacceptable dust concentrations is not surprising as poor dust control was found in all six wall tile and sanitary ware factories surveyed by the National Centre for Occupational Health between 1973 and 1989. Dust related occupational disease can be expected in potters for many years to come.

Topics: Air; Aluminum Silicates; Clay; Humans; Occupational Exposure; Pneumoconiosis; Quartz; South Africa

Topics: Aluminum Silicates; China; Clay; Humans; Pneumoconiosis; Pulmonary Fibrosis; Tuberculosis; Tuberculosis, Pulmonary