Respiratory system silicosis

NIOSH REL is 6 mg/m and OSHA PEL 80 mg/m for diatomaceous earth. Inhalation of crystalline silica causes dryness and irritation to the respiratory system. Symptoms may include coughing, sore throat, breathing difficulty (dyspnea), and wheezing. Excessive inhalation may cause decreased pulmonary function, limg damage and silicosis. Acute silicosis is manifested by dyspnea, fever, cough, and weight loss. Severe respiratory symptoms may lead to death. 

Inhalation is by far the most dangerous method of exposure. Regular medical examination of workers did not show that silicosis is caused by amorphous silica even under the most extreme conditions, but exceeding certain safe concentration may have damaging effects due to overloading of the respiratory system. 

A high proportion of the occupational diseases caused by special substances are diseases of the respiratory tract, in particular, so-caUed pneiunoconiosis in the mining industry and silicosis, which is activated by quartz and particulate matter. Although these dusts themselves are not toxic, they can lead to chronic pulmonary damage as a result of an overload of the cleaning systems of the respiratory tract... 

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