Compositional and structural analysis of engineered stones and inorganic particles in silicotic nodules of exposed workers

Background Engineered stone silicosis is an emerging disease in many countries worldwide produced by the inhalation of respirable dust of engineered stone. This silicosis has a high incidence among young workers, with a short latency period and greater aggressiveness than silicosis caused by natural materials. Although the silica content is very high and this is the key factor, it has been postulated that other constituents in engineered stones can influence the aggressiveness of the disease. Different samples of engineered stone countertops (fabricated by workers during the years prior to their diagnoses), as well as seven lung samples from exposed patients, were analyzed by multiple techniques. Results The different countertops were composed of SiO2 in percentages between 87.9 and 99.6%, with variable relationships of quartz and cristobalite depending on the sample. The most abundant metals were Al, Na, Fe, Ca and Ti. The most frequent volatile organic compounds were styrene, toluene and m-xylene, and among the polycyclic aromatic hydrocarbons, phenanthrene and naphthalene were detected in all samples. Patients were all males, between 26 and 46 years-old (average age: 36) at the moment of the diagnosis. They were exposed to the engineered stone an average time of 14 years. At diagnosis, only one patient had progressive massive fibrosis. After a follow-up period of 8 ± 3 years, four patients presented progressive massive fibrosis. Samples obtained from lung biopsies most frequently showed well or ill-defined nodules, composed of histiocytic cells and fibroblasts without central hyalinization. All tissue samples showed high proportion of Si and Al at the center of the nodules, becoming sparser at the periphery. Al to Si content ratios turned out to be higher than 1 in two of the studied cases. Correlation between Si and Al was very high (r = 0.93). Conclusion Some of the volatile organic compounds, polycyclic aromatic hydrocarbons and metals detected in the studied countertop samples have been described as causative of lung inflammation and respiratory disease. Among inorganic constituents, aluminum has been a relevant component within the silicotic nodule, reaching atomic concentrations even higher than silicon in some cases. Such concentrations, both for silicon and aluminum showed a decreasing tendency from the center of the nodule towards its frontier.

A Case Report of Silicosis: Culprit of Progressive Massive Fibrosis

Silicosis is a fibronodular lung disease secondary to the inhalation of crystalline silica dust. It had continued to cause significant morbidity and mortality worldwide. Here is a case of a 63-year-old woman, a lifelong non-smoker who complained of intermittent wheezing since retired 8 years ago. She had worked in the clay and piping industry for more than a decade. She wore only a simple 3-ply face mask at work without other protective devices. She had multiple hospital admissions for acute exacerbation of chronic lung disease for the past several years. Respiratory examinations revealed bilateral fine crepitations and occasional rhonchi on auscultation. Chest radiograph revealed ground glass changes. Pulmonary function testing showed an irreversible severe obstruction picture with an FEV1 of 45%. High resolution computed tomography thorax demonstrated hyperinflated lungs with emphysematous changes and multiple nodules over subpleural region, conglomerate mass with calcifications over bilateral lungs. Her imaging findings combined with a significant occupational history were suggestive of progressive massive fibrosis (PMF) due to silicosis. She is currently being treated with several inhalers and does not require home oxygen therapy. She is suffering from accelerated silicosis which may potentially progress to radiological deterioration, altered respiratory function and premature death. Therefore, it is essential to avoid any potential hazards that may predispose to silicosis.

Radiological Manifestation of Progressive Massive Fibrosis as a Complication of Silicosis-Case Report

Progressive massive fibrosis (PMF) is the outcome of complicated silicosis and falls in the category of occupational lung diseases. The underlying etiological factors responsible for this are fine particles of silica, inhaled by workers in certain specific occupation. We present a 42-year-old male patient with chief complaint of breathlessness and had occupational background in relation to sandblasting. HRCT chest had shown confluent fibrotic densities in bilateral upper lobes with loco regional bronchietatic changes and adjacent pleural thickening. The patient was diagnosed of having PMF on the history and classical HRCT findings