El agua natural puede contener materias en suspensión, sales minerales y materia orgánica disuelta. Los microrganismos son también parte de la materia en suspensión.
The first condition necessary for the quality of a drinking water is the absence of microorganisms. Since they are associated as suspended matter, filtration is an essential water treatment, since apart from eliminating the turbidity that gives an earthy taste, it greatly facilitates disinfection. For this reason, in many places where there is poor water quality in developing countries, filters, even manual, are recommended as the most efficient measure.
Disinfection is completed by the use of chlorine. It is necessary not to confuse the chlorine element, which is actually dosed as sodium hypochlorite, with the chloride anion, one of the elements responsible for the salinity of water and an ion that is not harmful to health.
¿ POR QUÉ SE AÑADE CLORO AL AGUA?
As for hypochlorite, it is not irritating at the doses used, -less than one part per million-, so its only effect is the slight taste that can be perceived, especially when the dose is close to 1 part per million and it is summer, when a gas is more easily released from the liquid in which it is dissolved. On the other hand, one must be aware that chlorine protects against infectious diseases that have been a scourge throughout history, such as cholera, which caused countless deaths, especially among children.
As a result, the microbiological quality of water in Spain is very high. Only in rare cases is the age of the distribution network so high that the presence of suspended matter can be suspected. And only in cases of pipe branches with water that has been standing for a long time can there be some accumulation of biofilm. In these rare cases, it is recommended to let the water run before use.
¿APORTAN BENEFICIOS LAS AGUAS MINERALES?
As for mineral salts, those found in natural waters do not have a significant effect on health. In any water, they are in small quantities. There are more salts in foods. If anything, the presence of bicarbonates may have a slight digestive effect by neutralizing the possible excess of stomach acid after a digestion with acidity, but the effect is very small. As for the hardness, that is to say, calcium, it can have in some cases a certain favoring effect on kidney stones, but on the contrary it can favor the strengthening of the bones. Therefore, in people of normal health, its overall effect is not very influential on health. Its only real effect is to give a certain metallic taste to the water, which is perceived by people accustomed to low mineralized waters.
Otros iones, como el sulfato o el magnesio, tienen todavía menos influencia, por mucho que, en el siglo XIX, con la moda del termalismo, se les atribuyeran diversas propiedades. En cuanto a oligoelementos como el selenio o el zinc , su presencia es testimonial y su promoción obedece a intereses comerciales.
As for dissolved organic matter, urban waters in towns of a certain size are filtered by activated carbon, which adsorbs both natural and artificial organic molecules, which in any case are found in low concentrations.
Por ello las aguas minerales no merecen la pena por sus supuestos efectos beneficiosos sobre la salud, tanto las de baja mineralización como las de alta. Como hemos dicho, sólo en casos particulares, como agua para bebés, pueden tener cierto interés, o bien si se desea un sabor que se percibe como más agradable. Se paga un precio bastante alto por algo que obtenido del grifo es casi gratis.
¿HAY RIESGOS ASOCIADOS A LAS BOTELLAS DE PLÁSTICO?
Hay que tener además en cuenta que también el plástico de las botellas puede transferir ciertos compuestos, como los ftalatos, que están siendo cuestionados por sus posibles efectos perjudiciales.
IMPACTO AMBIENTAL DE LAS BOTELLAS DE AGUA MINERAL
En cualquier caso, la contaminación por envases de agua que se desechan es dañina, pues el reciclaje es bastante escaso y además costoso. La baja eficacia del reciclaje y su efecto tranquilizador de conciencia frente a lo realmente deseable, que sería reducir el consumo de envases, merecen un capítulo aparte. En conclusión en la mayoría de situaciones cotidianas no hay una ventaja sanitaria significativa del agua mineral frente a un agua de red de calidad adecuadamente tratada, aunque como hemos dicho, el sabor puede ser percibido como más agradable.
