The first steps in salt treatment (also known as halotherapy, from the Greek word halos for salt) were taken during the middle ages, when monks treated the sick in salt caves. Salt dust was produced by grinding evaporite (or salt deposit) rocks against each other. This dust was then directed to the alveolar (breathing) air of the patient. Also, salt treatment that takes place in salt mines is called speleotherapy, from the Greek word speleos for cave.
In the mid-1800s, Felix Botchkowski, the state authority for occupational health in Polish industry, noticed that people who worked in salt mines only rarely suffered from lung-related diseases. In 1843 he published a book that presented his findings on the effects of salt dust. His successor, Mstislav Poljakowski, went on to establish a halotherapy clinic in Velicko, near Krakow.
During World War II, salt mines in Germany were used as bomb shelters. During bombardments, people often had to remain in the mines for extended periods of time. Upon leaving, many asthmatics felt themselves able to breathe much more easily.
In the former Soviet Union, speleotherapy was initiated in 1968 in the village of Solotvino, in Carpathia. An allergy hospital was set up at the bottom of Mine Number 8.
During the last twenty years, several hundreds of so-called salt rooms have been built in Central European hospitals and treatment facilities. Interest in salt rooms in other parts of Europe has also noticeably increased in the last few years. Despite this more modern and advanced form of treatment, it still goes by the traditional name of halotherapy.
Originally, salt rooms were constructed from bricks that had been cut from evaporite. Resultantly, the surface was dense as glass. Later, the frame of the salt room was constructed of sawn lumber and covered with netting and a glue-salt mixture, whereupon adhesion of the salt to the frame was poor and required a thick layer of the mixture. Moreover, the roughcasting process permeated the structure with moisture that was difficult and time-consuming to remove. The method also resulted in color and odor problems inside the salt room.
But due to considerable developments, the newest patented technique differs from this significantly. The frame of the salt room is covered on the inside with panels, which receive a coat of salt with the help of special anchor paint. The surface of the panels is left with a porous layer of salt that dries and hardens in a couple of days. In this way, the surface is made to have a distinctly ionizing effect.
The scientific study of salt room halotherapy (or salt room therapy) started in Finland in 2003 under the direction of the South Karelia Allergy and Environment Institute. An interim report was released in the autumn of 2006. The research project concluded in the spring of 2007, and a final report was released in the autumn of 2007.