Determination of total and hexavalent chromium concentrations in the atmosphere of the city of Isfahan.

Airborne particulate matter was collected from the atmosphere of the city of Isfahan by a high-volume air sampler. Determination of the concentration of total chromium was carried out by graphite furnace atomic absorption spectrometry after acid digestion. The determination of hexavalent chromium was carried out by ion chromatography following the collection of Cr(vi) in an impinger. Day-to-day variations in concentrations of total and hexavalent chromium were investigated and an excellent similarity was found between them. Atmospheric levels of total and hexavalent chromium were also investigated in different months of the year, and maximum concentrations were found in October.