Medical Hydrology and Balneology: Environmental Aspects

Determination of selenium in mineral and
thermal waters in the province of Ourense
(Spain): its importance in human biochemistry
Souto MG (1) , Vergnes Ph (1) , Pascual MJ (2) , Pascual E (3) , Freire A (4)
(1) Sociéte Française de Thermalisme et de Thalassothérapie pour la Santé Bucco-dentaire
(2) Hospital of Verín. Spain
(3) Institute of Ourense, Ourense, Spain
(4) Aguas Santas and Río Pambre Spas. Lugo, Spain
maritasouto@eresmas.com
Introduction and Objectives
Introduction: Galicia is a region with a remarkable shortage of selenium, as
shown in a doctoral thesis conducted at the Department of Analytical Chemistry,
Nutrition and Food Science, Faculty of Chemistry, University of Santiago de Compostela,
in which selenium levels in newborns and their mothers were studied.
That is the reason why searching for new sources of selenium in Galicia must be
considered. At present no data are available about the possible levels of selenium in
thermal mineral waters in the province of Ourense (Galicia). Therefore the determination
of this parameter is extremely important and its existence would add value
to the healthy virtues of these waters.
Selenium is important for its antioxidant function, being part of the active site of
the glutathione peroxidase enzyme, an enzyme which is necessary for maintaining
the integrity of cell membranes and which catalyzes the reduction of a wide variety
of organic peroxides and hydrogen peroxide.
These radicals can be formed as a result of the metabolism of toxic substances,
ethanol, medicines and chlorinated derivatives; in today's society they are associated
with stress experienced by individuals. Considering this starting point, several
biochemical mechanisms that involve selenoproteins have been described, being
specially important the glutathione peroxidase, forming part of the defense mechanism
of antioxidants.
There is evidence that many of the diseases and problems associated with selenium
deficiency are caused by reduced levels of this enzyme.
The glutathione peroxidase, vitamin E and other enzymes such as catalase, superoxide
dismutase and glutathione transferase, are the essential cellular defense
mechanism against hydrogen peroxide and free radicals.
This protection is particularly important in maintaining cell membranes, whose
integrity and proper functioning is essential in order to maintain the systems and
Balnea
2012, núm. 6, 202-204
202
ISBN: 978-84-669-1887-0
978-84-669-3482-4