Determination of heavy metals in textile materials by atomic absorption spectrometry: Verification of the test method

The objective of this research was to identify the analytical steps affecting the quantitative assessment for the
determination of heavy metals in textile materials and to test the selected extraction conditions, with the intent of
developing a standardized and shared method that would help promote textile products, both in terms of safety
for the environment and health of citizens, and of safety for workers exposed during the production process and
for end users. The method was applied to a textile materials dyed with a chromium dyestuff at two different
concentrations. The metals analyzed were total Cr and Cr VI. The extraction was carried out by means of the
artificial perspiration solution, according to the standard adopted by the most important textile ecolabelling
schemes operating in the European market. The extract was filtered under vacuum and analyzed by means of
atomic absorption spectrometry for total Cr and UV-Visible spectroscopy for Cr VI. The tests were carried out
varying some extraction parameters as temperature of the solution, time of contact and material-to-liquor ratio
extraction. Finally the metal extraction profit was derived by the determination of total chromium in the ashes.
The results show that the quantity of total chromium and CrVI extracted is affected principally by the temperature
of the solution and by the material-to-liquor ratio extraction, and less by the time of contact. The percentage of
metal extraction profit vary according to the extraction conditions, from 32% to 44%.