What are Total Dissolved Solids (TDS)?

In its natural state, water is often contaminated with various minerals that occur in nature.

Ces contaminants peuvent être des matières dissoutes totales. Ils sont des contaminants organique et inorganique pouvant se retrouver dans l’eau de façon naturelle ou non.

Generally speaking, dissolved materials are calcium, magnesium, sodium or potassium cations. They can also be anions such as carbonate, bicarbonate, chloride, sulfate or even nitrate.


The Source

As stated above, they can be from human activity or they can be from natural sources: typically, soil erosion, runoff or decomposition of flora and fauna. In terms of human activities, road de-icing in Canada is one example of human actions that can promote the spread of TDS in Canadian waters.


Why monitor them?

Although water concentrated in total dissolved solids is not hazardous for human consumption, water highly concentrated in TDS may be an indicator of poor treatment. It is important to note that while TDS in water is not hazardous for human consumption, concentrations of 1000 mg/L and above are considered unfit for human consumption.

The World Health Organization, after various studies, has come to the conclusion that the acceptable TDS levels are as follows

Total dissolved solids in mg/L       

 

< 300

Excellent

300 -600

Good

600– 900

All right

900– 1200

Poor

>1200

Very Poor

To identify the amounts of dissolved solids in a sample, the easiest way is to use a total dissolved solids meter.


How to decrease the total dissolved solids in water?

L’extraction des MDT se fait relativement facilement. En fonction des types de matières dissoutes dans l’eau, les technologies comme l’osmose inversée, la nanofiltration, la distillation et la déionisation se sont prouvées efficaces pour diminuer les concentrations en matières dissoutes.

Water and its Minerals
The variety of minerals that can be found in water through soil erosion is very diverse and changes from place to place.