[3] Pulmonary siderosis does not usually cause harmful scar tissue formation within the lungs, which is why it said to be non-fibrotic condition, unlike asbestosis for example, and has also been called "benign pneumoconiosis".

Because of this, it is not known for certain whether the inhalation of pure iron or rust can cause detrimental scarring of the lungs that has been seen in some cases of pulmonary siderosis.

[7][8] Pulmonary siderosis is caused by repeated inhalation of fine iron or rust dust that happens usually over a number of years.

[5][2] Pulmonary siderosis causes changes within the lungs that are clearly visible in tissue samples, x-ray images and other radiological studies.

[5] Outcome of pulmonary siderosis is often good if the inhalation of iron or rust dust is permanently avoided.