TDS stands for Total Dissolved Solids, which refers to the total concentration of dissolved substances in water. TDS is made up of inorganic salts, as well as a small amount of organic matter. Common inorganic salts that can be found in water include calcium, magnesium, potassium, and sodium, which are all cations, and carbonates, nitrates, bicarbonates, chlorides, and sulfates, which are all anions. Cations are positively charged ions, and anions are negatively charged ions. TDS can affect the taste and appearance of water.
TDS can originate from a number of sources, both natural and as a result of human activities. Mineral springs contain water with high levels of dissolved solids because the water has flowed through a region where the rocks have a high salt content. The water in the Prairie provinces tends to have high levels of dissolved solids because of high amounts of calcium and magnesium in the ground. Dissolved solids can enter the water supply from a wide range of sources, including old piping, run-off from road salts, pesticides, fertilizers, and other sources.
It is important to measure TDS levels in drinking water to understand the quality of the water. However, having total dissolved solids in water is not necessarily good or bad. The dissolved solids in the water are the mineral content of the water. Absolutely pure water with virtually no dissolved solids, like deionized water, can taste flat, can be acidic, and the long-term consumption of absolutely pure water may cause acidosis. In addition, if deionized water is run through standard metal piping or fixtures, it can cause corrosion and elevated metals in the water.
