Kurdistan, Kermanshah, Ilam and Khuzestan are among the hardest hit provinces in Iran where residents with heart and respiratory problems have been warned to stay indoors, Iranian media reported.
Various reports have indicated that the amount of dust in the air is 20 to 30 times more than the healthy level.
Flights to and from the provinces as well as the Iranian capital city of Tehran have been canceled as massive dust clouds have swept in from the west.
The storms began three days ago but have intensified in the past two days, according to reports.
Residents in the western and southwestern provinces that border Iraq face a growing trend in the influx of fine particles, which are generated by drought-hit marshlands in neighboring countries.
The disruptive dust storms have pushed pollution in those border areas to alarming levels in recent years, raising health concerns.
The particles, carried by winds, can penetrate the lungs and enter the bloodstream, causing serious diseases such as lung cancer, asthma and heart problems.