APPLICATION OF INFRARED SPECTROMETRY (FT-IR) FOR MINERAL IDENTIFICATION OF ASBESTOS IN BULK SAMPLES

Background: The aim of this study was to apply infrared spectrometry (FTIR) in mineral identification of asbestos in bulk materials. Material and Methods: The identification of asbestos was based on infrared spectra of UICC and NIST: SRM 1866a and SRM 1867 standard asbestos, and infrared spectra of heat treatment chrysotile, crocidolite and amosite asbestos. The samples of bulk materials were grinded and fibers were isolated from samples. The KBr disc standard technique was used in the preparation of samples for infrared measurements. The infrared spectra were recorded in transmittance function, at resolution of 4 cm(1) and for 32 averaged scans. Results: The analysis of the infrared spectra revealed that chrysotile, crocidolite, amosite and anthophyllite asbestos can be identified in industrial products and distinguished in mixtures. Spectra of fibrous materials do not interfere with spectra of asbestos. When analyzing the whole sample mass, interferences from the components of construction materials can be eliminated or reduced by using computer transforming spectra, preliminary purification of samples or separation of sample components. The method used permit to identify from 2 to 4 mu g of the three basic forms of asbestos. Spectra of chrysotile and amosite heated to 500 degrees C and crocidolite heated to 300 degrees C are the same as non-heated forms. Heating in higher temperature induces characteristic changes in spectra and the transformation of asbestos into other minerals. Conclusions: infrared spectrometry can be used for routine identification of asbestos in samples of bulk materials also treated with high temperature, and to assess the effectiveness of asbestos waste detoxification. Med Pr 2012;63(2):181-189