Barium concentrations and speciation in mineral natural waters of central Romania.

This paper reports the results obtained for the determination of Ba concentrations in mineral groundwater samples collected from drilled outlets located in the counties of Covasna and Harghita (34 sampling points), in five expeditions (spring, summer, and autumn), during 3 years: 2005, 2006, and 2007. The experimental data show that there are some sampling sites in which the barium concentration exceeds 1 mg/L, which is the maximum concentration admitted for barium. These mineral natural waters could be used only for therapeutic purposes. All other analyzed natural mineral waters are proper as both drinking and therapeutic water. By means of a principal component analysis a statistical approach was performed, using the data obtained during those analyzing processes. The distribution of the water saturation indexes with respect to a series of mineral species (alstonite, barite, barytocalcite, nitrobarite, sanbornite, and witherite) suggests that barium tends to remain in solution as ionic species in different concentrations and to be further carried away as such.