Certification of reference materials for the quality control of major element determinations in groundwater .1. Feasibility study

Analyses of groundwater are routinely performed by control laboratories within the European Union to monitor the levels of major elements. The quality control of such determinations requires the use of certified reference materials which are representative of natural samples. However, the preparation and stabilisation of natural groundwater for their major element composition is difficult to achieve and materials simulating; the mean composition of real samples often represent the best alternative. In order to investigate the feasibility of preparation and stabilisation of simulated groundwater samples, various tests were necessary prior to the production of a large batch of candidate reference materials. This paper presents the preparation of simulated groundwater reference materials and the different stabilisation procedures tested.