INTRODUCTION: The first objective of the study was to investigate the relationships between quantitative lung mineral dust burdens, dust exposure history, and pathological @entity82 grading in silicotic workers. The second objective was to evaluate the association between particle size parameters, concentration of retained @entity3440 particles and the severity of the @entity5636 . Sixty-seven paraffin-embedded lung tissue samples of silicotic @entity1 were analyzed. The cases of @entity5636 included 39 @entity2 @entity1 and 28 @entity1 with @entity2 . All of the cases were gold miners in the Province of Ontario, Canada. MATERIAL AND METHODS: Particles, both angular and fibrous, were extracted from lung parenchyma by a bleach digestion method, mounted on @entity920 microscopic grids by a @entity505 replica technique, and analyzed by transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). @entity3674 concentration was also determined by X-ray diffraction (XRD) on a silver membrane filter after the extraction from the lung parenchyma. RESULTS: Total particles, @entity3440 , clay, and @entity3674 also increase in concentration with increased age at death, although the trends are not statistically significant. @entity3674 concentration has a statistically significant correlation with the @entity5636 severity score (r = +0.45, p < 0.001), with the geometric mean concentration increasing from 2.24 micrograms/mg in the group having @entity5636 severity score less than 1 to 4.80 micrograms/mg in group with highest score. @entity3674 concentration is the only significant explanatory variable of the @entity5636 severity with a regression coefficient of +0.41 (p < 0.001). CONCLUSION: Among several dust exposure variables extracted from the work history of the miners, the calendar year of first exposure was the primary significant determinant of lung retained total particles, @entity3440 , and clay minerals, except for @entity3674 . A statistically significant linear relationship between lung @entity3674 concentration and @entity5636 severity in the gold miners was observed (p < 0.001). Among the several types of lung particles detected, @entity3674 was the only significant determinant of the @entity5636 severity in the gold miners in this study and vice versa, although it explained only 20% of the variation in the severity. This study suggested no significant linear relationship between the duration of dust exposure and the lung burden of any particle types in the gold miners.

Tentative explanatory variable of lung dust concentration in gold miners exposed to crystalline XXXX .

@entity1 :: ('9606', 'Species') :: ['patients'] @entity82 :: ('MESH:D005355', 'Disease') :: ['fibrosis'] @entity5636 :: ('MESH:D012829', 'Disease') :: ['silicosis'] @entity2 :: ('MESH:D008175', 'Disease') :: ['lung cancer', 'non-lung cancer'] @entity920 :: ('MESH:D003300', 'Chemical') :: ['copper'] @entity3440 :: ('MESH:D012822', 'Chemical') :: ['silica'] @entity3674 :: ('MESH:D011791', 'Chemical') :: ['quartz', 'Quartz'] @entity505 :: ('MESH:D002244', 'Chemical') :: ['carbon']
@entity3440 :: (MESH:D012822,Chemical) :: ['silica']
