Each pollution pattern has general and particular evaluation indexes. The general ones are referring to the quantity of pollutant for a certain water volume (liter or cubic meter) - g/l, g/cm or, for the highly toxic pollution - mg/l, mg/cm. There are also specific indexes, such as the level of toxicity of a pollutant for the existing biosphere in the local environment (for example, mg of toxic substances for the fish metabolism blocking or even for their death).