This week’s giant dust storm (technically called a haboob) blew through the valley leaving dust hovering in the air for days.  The ADEQ said one Phoenix testing station recorded an astronomical reading of over 6,000 micrograms per cubic meter (of PM 10) on Tuesday evening (the federal EPA standard is 150 averaged over a day).  PM 10 is a measurement of the concentration of particles in the air that are smaller than 10 microns in size.  We’re most interested in particles smaller than 10 microns because they actually make it into the lungs (larger particles get trapped in your throat and nose and don’t make it to the lungs where the damage can be done).

The dust storm also blew in concerns about Valley Fever.  Valley Fever is caused by a fungus and its spores that grow in the top layers of the desert soil (below 4,000 feet elevation).  Strong winds may be able to disrupt it and pick up the fungus. ADHS does a little research into Valley Fever cases by interviewing and reviewing case files of those who have been diagnosed.  We have a video on our website to help people understand the disease and how to talk to their doctors about it.  The truth is that we don’t really know for sure whether dust storms actually make people sick with Valley Fever- but we’ll be following our surveillance data after this extraordinary event to see whether the storm had an impact on rates.  To learn more, visit the ADHS valley fever website at