This term refers to the collection of substances contained within water, notably drinking water.  TDS can be molecular or micro-granular in size, and is typically comprised of minerals like calcium, magnesium, and manganese.  High TDS counts can create taste issues.

The United States has established water quality standards to account for safe levels of total dissolved solids, though these standards are not always adhered to.  On top of these standards, Quench recommends reverse osmosis (RO) water filtration for water with TDS over 350 ppm (parts per million).  RO typically reduces TDS to under 25 ppm; distillation reduces TDS to under 10 ppm.

Bottled mineral water typically has a TDS level 400-650 ppm.