The use of LA-ICP-MS for the characterization of the micro-heterogeneity of heavy metals in BCR CRM 680

Abstract

BCR CRM 680 is a newly (year 2001) released reference material consisting of a polyolefinic matrix doped with various metallic compounds in trace concentrations, to be used for calibration of multi-element trace analytical methods. The micro-heterogeneity of CRM 680 was investigated by means of laser ablation inductively coupled plasma spectrometry (LA-ICP-MS) in order to evaluate the suitability of this reference material for calibration of trace-level micro-analytical techniques. The measurements involve an extensive series of local analyses, performed in identical conditions at different locations on the material. Special attention was paid to the proper manner of data selection and normalization in order to eliminate any interdependence or correlation between the data points. The procedure was employed to evaluate the micro-heterogeneity of BCR CRM 680 by calculating the minimal sampling mass. The micro-heterogeneity results obtained with LA-ICP-MS were compared with those obtained by means of synchrotron micro X-ray fluorescence analysis, a non-destructive trace-level micro-analysis technique (μ-XRF), and satisfactory agreement between both sets of results was observed. LA-ICP-MS was found to be suitable for the characterization of the micro-heterogeneity of trace metals in polymer reference materials.