Abstract
A simple, sensitive and accurate method for quantifying chromium collected on air sampling filters in the presence of iron is reported. This procedure, based on inductively coupled plasma atomic emission spectrometry (ICP-AES), eliminates the need for chemical agents which are necessary to minimize the suppressive interference from iron in flame-atomic absorption spectrophotometry (flame-AAS). The extent of this interference in flame-AAS is illustrated, and the development of the ICP-AES technique is described. The spectral background of the analytical wavelength for chromium at 267.72 nm was examined. The linear analytical range was from 0.1 µg to 5.0 mg in 20.0 mL solution. The recovery at 0.5 µg to 100.0 µg in the presence of 0.5 µg to 3.0 mg of iron was from 87% to 102%. When air sampling filters collected at welding sites were analyzed for trace levels of chromium, the accuracy of this method was demonstrated despite the presence of up to 2 mg of iron.