Short report 30.10.2015, Action A5 “Environmental analysis”

Abstract

The study deals with the analysis of relationship between chemical composition of the groundwater / drinking water and the data on mortality for oncological diseases (MOD) in the Slovak Republic. Primary data consist of the Slovak national database of groundwater analyses (20,339 chemical analyses, 34 chemical elements/compounds) and data on MOD (17 health indicators) collected for the 10 years period (1994-2003). The chemical and health data were unified in the same form and expressed as the mean values for each of 2,883 municipalities within the Slovak Republic for further analysis. Pearson and Spearman correlation as well as artificial neural network (ANN) method were used for analysis of relationship between chemical composition of groundwater/drinking water and MOD.  The most significant chemical elements having influence on MOD relative mortality were identified together with their limit values (limit and optimal contents). Based on the results of calculations, made through the neural networks, the following eight chemical elements/parameters in the groundwater were defined as the most significant for MOD: Ca+Mg (mmol l^-1), Ca, Mg, TDS, Cl, HCO₃, SO₄ and NO₃.

The obtained results document the highest relationship between MOD  and groundwater contents of Ca+Mg (mmol l^-1), Ca and Mg. We observe increased MOD with low (deficit) contents of these three parameters of groundwater/drinking water. Following limit values were set for the most significant groundwater chemicals/parameters: Ca+Mg 1.73 – 5.85 mmol l^-1, Ca 60.5 – 196.8  mg l^-1 and Mg 25.6 – 35.8 mg l^-1. At these concentration ranges the mortality for oncological diseases in the Slovak Republic reaches the lowest levels. These limit values are about twice higher in comparison with the current Slovak valid guideline values for the drinking water.

Full text for dowload: A5_short report_Oct 2015