Benefits of Mud/clay and Thermal Spring Water in the Human Health

The appropriate use of minerals and other mineral resources in geomedicine can reduce both pharmacs consumption and the number of working days people miss due to health problems. The main goal of the present communication is the study of the muds/clays being used in Portugal for health treatments, outdoors in the geological sites where they naturally occur or indoors in Thalassotherapy Centres or in Thermal Spas. Portugal is rich in excellent minero -medicinal waters, some of them of marked thermal character. Their diversity is great, in terms of chemical and physical properties, and they are being the object of a fine characterisation programme by the authors of the present communication. Such characterisation has started with Vale das Furnas, S. Miguel island, Azores archipelago, where more than two dozens of springs of hyperthermal, mesothermal and hypothermal waters do occur. Some of the hyperthermal springs deposit muds that are being used in the treatment of certain diseases. The experimental data available so far allowed us to conclude that all the studied clays/muds have good potentialities to be used for specific mudtherapy applications. The appropriate use of minerals and other mineral resources in geomedicine can reduce both pharmacs consumption and the number of working days people miss due to health problems. INTRODUCTION At present there is a growing interest and preference in many areas of human health care for treatments involving natural means rather than for treatments involving only means of conventional medicine. It is the so-called naturotherapy, that involves distinct methodologies, such as: phytotherapy, hydrotherapy, mudtherapy, thermotherapy, etc. (Gomes & Silva, 2001). Whenever naturotherapy involves minerals (for instance, special clays, special sands and rock salt), or other mineral resources (for instance, sea water and thermal spring water) it could be named geomedicine (Gomes & Silva, 2001). Mudtherapy or "pelotherapy", that is the use of mud/clay (both pelitic geological materials) for internal or external therapeutic applications, presently deserves more and more attention and interest from people who suffer from some unfortunately very frequent rheumatic, physiatric, orthopaedic and skin diseases, which seriously affect their living quality. Mudtherapy or "peloidtherapy" in human health care has been a common practice since historical times. Conceptually, the term mud does not coincide always, in what mineralogy is concerned, with the term clay in which clay minerals are essential components. Also, specific clays are important components of pharmacs, partic ipating as fillers, excipients or active principles. Pelitic geomaterials such as clays have been used for ages in geomedicine. In fact, particular types of clays are still used worldwide, either in thalassotherapy centres of some spas or in geologic sites, for therapeutic treatments generally related with arthro-rheumatic, and skin diseases. Both sedimentary and hydrothermal clays, without or with little previous preparation, are being used as healing materials. In recent years the number of scientific publications concerned with the use of Environment 2010: Situation and Perspectives for the European Union PAPER C 04 6-10 May 2003. Porto, Portugal ______________________________________________________________________________________________________ ______________________________________________________________________________________________________ BENEFITS OF MINERALS IN THE HUMAN HEALTH Page 2 of 5 clays in geomedicine has increased, some of them deserving to be emphasized: Ferrand & Yvon (1991), Barbieri (1996), Yvon & Ferrand (1996), Novelli (1996), Veniale & Setti (1996), Reinbacher (1999) and Cara et al. (1996, 2000a; 2000b). Portugal is a country excepcionally rich in thermal minero-medicinal waters. Traditionally, in Portugal, several Thermal Centres or Spas are being used, particularly by people of age over 40, for the treatment of certain health affections of neuro-muscular, gastro-intestinal, epidermic/dermic, articular and respiratory nature. However, thermalism in Portugal, needs to be revitalized, in order to become able to offer new products and treatments. It is the case, for instance, of the use of "peloids", generally made up of mixtures of clay/thermal spring water or sea water, which are being used worldwide, either in Thalassotherapy Centres or "in situ" in geologic sites, for therapeutic treatments called mudtherapy or pelotherapy. Contrary to countries such as Italy, Spain. France and Germany, in Portugal the number of Thalassotherapy Centres or Thermal Centres using "peloids" is very small, just four as far as we know. On the other hand, the hydrochemical properties of the Portuguese thermal minero-medicinal waters requires more thorough studies, particularly in what concerns their trace elements. Also, some few Portuguese clays/muds, associated or not to thermal springs, require further studies, particularly in what concerns their relevant, textural, thermal and chemical properties. Amongst the various regions where thermal minero-medicinal springs and clays/muds do exist, Vale das Furnas, in S. Miguel island, Azores (fig. 1), has been selected for the kick-off of the proposed project due to its great potential in thermal minero -medicinal springs as well as in muds/clays deposited by the thermal springs, associated to small calderas and fumaroles. The authors of the present communication are involved in a research programme, whose main goal is the study of the muds/clays being used in Portugal for health treatments, outdoors in the geological sites where they naturally occur (located, generally, near the seaside) or indoors in Thalassotherapy Centres or in Thermal Spas, most of them requiring revitalization through the renewal of infrastructures and the introduction of new methodologies and products in order to become real polytherapy centres (Gomes, 2002). Portugal is rich in excellent minero-medicinal waters, some of them of marked thermal character. Their diversity is great, in terms of chemical and physical properties, and they are being the object of a fine characterisation programme by the authors of the present communication. Such characterisation has started with Vale das Furnas, S. Miguel island, Azores archipelago, where more than two dozens of springs of hyperthermal, mesothermal and hypothermal waters do occur. Some of the hyperthermal springs deposit muds that are being used in the treatment of certain diseases. MATERIALS AND METHODS S. Miguel island, in Azores archipelago, was formed around 4 My ago starting with the formation of the basaltic shield volcano active till 1My before present. This volcanic event has been followed by three volcanic episodes yielding the three stratovolcanos, named Nordeste, Povoação and Furnas, all of them being of plinian and subplinian character. The volcanism character being initially basaltic did evolve to trachytic. Related with the Furnas stratvolcano two main calderas were formed, one of them occupied by a lac named Lagoa das Furnas. In both calderas there exist two fumarolic fields. From small ponds and rock cavities hot whitish smokes are emited and profuse bubbling comes out from the hot mud that fills those ponds. Also, about two dozens of springs exist in Vale das Furnas, and the temperature of their waters goes up from the ambient temperature to 98oC. Muds are just deposited in the fumaroles yielding hyperthermal waters. PAPER C 04 Environment 2010: Situation and Perspectives for the European Union 6-10 May 2003. Porto, Portugal ______________________________________________________________________________________________________ ______________________________________________________________________________________________________ BENEFITS OF MINERALS IN THE HUMAN HEALTH page 3 of 5 Figure 1 – Location of study area and sampling sites Nine hot springs (52oC ~ 98oC) were sampled (fig. 1) and analyzed to determine the physical and chemical characteristics of both muds and waters (samples 8A, 8B, 10C, 12D, 16E and 19G) or just for waters (7, 9 and 11). A sample (17F) representative of mud and water being used in the Vale das Furnas Thermal Spa was also collected. In the case of muds/clays, properties such as: chemical and mineralogical composition, texture, specific surface, total ion exchange capacity and exchange ions, abrasivity, expansibility, adsorption and absorption, specific heat, and heat diffusiveness are under study. As a matter of fact, the most relevant assets of peloids to be used in the form of warm patches or cataplasms are as follows: high specific surface area, high cation exchange capacity, high specific heat and low cooling rate. All the properties referred to are dependent upon both granularity and mineral and chemical composition of clay or mud. Clay or mud particles can be smaller than bacteria and these whenever coated or encapsulated by clay particles lose activity and can be eliminated. Samples of water were collected from hot to warm springs which are located within the caldera. Locality map of sampling points of thermal springs is shown in figure 1. Samples were filtrated with 0.45 mm cellulose acetate membrane filter (Hunt & Wilson, 1986). Temperature, pH and conductivity were also measured in the place. Chemical analyses were performed following the procedures described by EPA (1983) and ASTM (1984). Bicarbonates were measured by acid titration to pH 4.5 using a mixed indicator of methyl red and bromcresol green; major anions and cations by Dionex Ion Chromatography (chloride, nitrate, Azores 8A 8B 10C 12D