A systematic review of the respiratory effects of occupational exposure to potassium bearing dusts

Studies have recently shown a correlation between the elemental components of coal dusts, including potassium aluminosilicates, and the lung response as a potential driver for lung diseases associated with inhalation of coal dust. Here we aimed to systematically review the evidence for the association between exposure to potassium bearing dusts and lung outcomes in human studies as well as adverse cellular response in animal/cell culture studies.

A systematic search of the National Library of Medicine (PubMed), Embase and Web of Science was conducted in May 2024. Studies regarding exposure to potassium bearing dusts and aluminosilicates and respiratory consequence were included in the search. Articles were screened, with a secondary assessment for relevance and extraction of key information using a systematic review process.

We identified 64 studies, of which 35 were human studies, 22 involved animal experiments and 12 were in vitro studies with 5 papers having both in vivo and in vitro studies. Our review found some evidence that a range of potassium rich dusts increased incidence of respiratory symptoms and lung diseases, although the effect on radiological changes in the lung and pulmonary function loss was not consistent. The in vivo animal and in vitro studies consistently demonstrated an inflammatory response and cytotoxic effect after exposure to these dusts.

Given complexity in the dust compositions and lack of direct evidence attributing these specific responses to potassium, we are not able to conclude the effect of potassium minerals in coal on development of respiratory diseases, warranting further research.