Abstract
Organic and inorganic substances in 36 well water samples in Kuwana area, northern part of Mie prefecture in Japan, were quantified.
Arsenic above 0.005mg·l-1 was detected by Hydride Generation Atomic Absorption Spectrometry (HG-AAS) method in 12 wells of 25-260m depth. 7 out of the 12 well water samples contained arsenic above the maximum permissible limit in drinking water in Japan although the wells were not used for drinking. Qualification by liquid chromatography with inductively coupled plasma mass spectrometry (LC-ICP⁄MS) showed that some of the samples contained arsenite (As(III)) above the limit. Deeper underground than 100m, arsenic was found only in the east side of Yoro Fault, which suggests that arsenic in groundwater is associated with some specific strata. Arsenic was slightly correlated with pH and iron. The concentrations of iron in arsenic-rich well waters were high.
The concentrations of iron and magnesium in the groundwater in this area were very high. Specific chemical compositions of the waters from the wells close to the sea suggest that the well waters were affected by seawater, and some of the samples contained arsenic.
