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Determination of Inorganic Arsenic in a Wide Range of Food Matrices using Hydride Generation - Atomic Absorption Spectrometry.
Published on: September 1, 2017
Selenium and arsenic in the environment in Finland
Summary
Finland
Area of Science:
- Environmental geochemistry
- Hydrogeochemistry
- Medical geology
Background:
- Precambrian glaciated environments, like Finland, exhibit low selenium (Se) concentrations due to its chalcophile nature, substituting sulfur in sulfide minerals.
- Se levels in Finnish rocks and till range from 0.01 to 0.2 mg/kg, resulting in low Se concentrations in surface and groundwater compared to other nations.
- Arsenic (As), a highly toxic metal, is a growing concern in Finland, with new regulations for potable water and high concentrations found in bedrock wells.
Purpose of the Study:
- To investigate selenium and arsenic concentrations and distributions in Finnish water and soil.
- To understand the hydrogeochemical behavior and sources of Se and As in the Finnish environment.
- To assess the environmental implications of Se-fertilization and the risks associated with As in drinking water.
Main Methods:
- Nationwide hydrogeochemical study of headwater streams, analyzing Se concentrations in water and sediment.
- Speciation analysis of Se in Finnish stream waters to determine its chemical forms.
- Assessment of As concentrations in till fines, groundwater, and bedrock wells, correlating with geological conditions.
Main Results:
- Median Se concentrations in Finnish streams were 30-180 microg/L, with stream water Se significantly correlated with sediment Se.
- In Finnish stream water, Se was equally distributed between humic substances and selenate, with selenite and particulate Se being minor components.
- High As concentrations, primarily from arsenopyrite, were found in bedrock wells (up to 1-2 mg/L), particularly in areas with sulfide mineralization and mafic rocks.
Conclusions:
- Finnish geological conditions lead to naturally low Se levels in water, though Se-fertilization has raised environmental concerns.
- Arsenic poses a significant risk in Finnish drinking water, especially from bedrock wells, necessitating understanding of local geology.
- The study highlights the importance of geological context in managing environmental contaminants like Se and As in water resources.
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