Following the classification of quartz as a human carcinogen by the IARC, many standard-setting committees are currently trying to convert this hazard into their national or EU standards. Since human data to set a safe exposure limit for quartz are limited, we hypothesized that lung burden data on quartz in coal miners' lungs after lifetime exposure could be used to set a non-carcinogenic lung ...

Quartz (α-quartz), is the most common crystalline silica polymorph in nature and is the only polymorph found in significant concentrations in coal and coal ash. Since exposure to quartz is liable to cause lung diseases, it is very important to know its concentrations in coal ash and to evaluate its effects on the workers. Inhalation is the most effective route of entry for airborne particles of...

From the application of chemical thermodynamics a quartz solubility regression expression along the water-vapor saturation curve for whole range of temperature from 0 to 374oC was developed. The equation is the following ( ) ( ) 08 . 0 88 . 4 ) ( 7 . 31 7 1175 ) ( log 2 ± + ± ⋅ − = K T ppm SiO The correction of total discharge silica composition from a well for the vapor fraction in the geother...

Pulmonary toxicology studies in rats demonstrate that nanoparticles are more toxic than fine-sized particles of similar chemistry. This study, however, provides evidence to contradict this theory. The aims of the study were (1) to compare the toxicity of synthetic 50 nm nanoquartz I particles versus (mined) Min-U-Sil quartz ( approximately 500 nm); the toxicity of synthetic 12 nm nanoquartz II ...

Introduction: Quartz is one of the most abundant minerals in terrestrial crustal rocks. Viewed in planepolarized light with a petrographic microscope, quartz is clear (i.e., transparent). In cross-polarized light, quartz typically displays gray to white interference colors. Quartz (and other minerals) is deformed and transformed when subjected to strong shock waves, as a consequence of impact e...