TDS Level for Drinking Water: The Ultimate Guide to Understanding TDS Range
Is TDS in the water really problematic? Well, it all depends on the level of TDS in water. Abnormally high TDS in water is a problem, drinking of which could cause health issues. You can refer the TDS chart below to find out the acceptable level of TDS in drinking water, but first we shall look at the concept of TDS level in water in detail.
Table of Contents
TDS – The Concept
In very simple terms, TDS stands for ‘Total Dissolved Solids’ and it comprises of inorganic as well as organic salts. The principal constituents that comprise TDS are calcium, magnesium, potassium, sodium, bicarbonate, sulphates, chlorides, and nitrate ions.
All the above listed principal constituents are macrominerals and do not cause harm to the human body. In fact, you need a majority of these minerals for ensuring good health; however, the proportion of these minerals in drinking water is the matter of contention. We shall look at what is acceptable and what is not as we go deep into the article.
TDS – Source
The sources of TDS are various. They range from natural sources to agricultural and urban runoff. Industrial wastes and sewage are also sources of TDS in water. There are external factors like contamination from road paving materials, plumbing materials, and so on. Research shows that natural sources account for as low as 30 mg/litre or sometimes as high as 6000 mg/litre depending on the solubility factor of minerals found in different geographical regions.
TDS – Effects
Does TDS in water constitute a health hazard? This is a relative question because you need TDS within certain acceptable limits. It becomes harmful only when it exceeds these limits. In fact, the TDS concentration is more of an aesthetic hazard as compared to a health hazard because it is a secondary drinking water standard.
High concentration of TDS can cause water to become corrosive, salty or develop a brackish taste. This results in the formation of scales in pipes, appliances like water heaters and washing machines thereby reducing their efficiency.
TDS Level Chart for Drinking Water in PPM
The following tables explain the acceptability of TDS in drinking water. We shall look at the broad palatability levels of water before delving deep into the matter.
| TDS Levels in mg/litre | Palatability Quotient |
|---|---|
| Less than 300 | This is considered excellent to drink |
| 300 to 500 | These levels are good |
| 600 to 900 | Fair |
| 900-1200 | This range constitutes poor palatability |
| Above 1200 | This is an unacceptable range |
According to the Bureau of Indian Standards (BIS), the upper level of TDS levels in water is 500 mg/litre (500 parts per million); however, TDS level in the range of 300 ppm is considered excellent per WHO Guidelines.
The above chart conveys the palatability quotient of drinking water at different TDS levels. There is a difference between palatability quotient and acceptable levels of TDS. The below table should make things clear. We go into the details explaining why water in the particular range is not acceptable.
| TDS level in mg/litre | Reasons for acceptability / non-acceptance |
|---|---|
| Less than 50 | This is a totally unacceptable level because water with such a low proportion of TDS does not contain the requisite minerals. |
| 50-150 | This is an acceptable level; however, TDS levels in the range of 80 to 150 is preferable. |
| 150-250 | As far as cardiovascular health is concerned, this level of TDS is the healthiest. |
| 250-350 | TDS in this range is acceptable. Many places in India have this level of TDS. |
| 350-500 | Any level below 500 mg/litre is acceptable for drinking. |
| 500-900 | TDS in this range is generally not acceptable for drinking; however, you can use RO water purifiers to reduce TDS level below 500. |
| 900-1200 | Not acceptable, but an RO water purifier can help reduce TDS to acceptable levels. |
| 1200-2000 | Water is not fit for drinking, but the latest RO water purifiers can reduce TDS levels up to 2000 ppm. |
| Above 2000 | Should not drink water with this TDS level. Household water purifiers cannot purify water with such high TDS level. |
As mentioned above, if the TDS level in water is more than 500 ppm, an RO water purifier is an ideal one to use at your home. Here is the list of best RO water purifiers that you can buy online. Perhaps this water purifier buying guide could also help you buy the right water purifier.
Frequently Asked Questions on TDS in Water
How to measure TDS in Water?
Measuring TDS is very simple. The easiest way to check TDS in water is by using the TDS meter. These devices are widely available online. You can find really cheap TDS meters at Amazon.
Why is TDS level below 50 mg/litre not ideal for consumption?
This is a good question. When you have less TDS in water, it implies that water is pure with less quantity of dissolved salts. Under such circumstances, water should be pure. Therefore, the question is a valid one.
Remember, we had said earlier that TDS concentration is a secondary drinking water standard. Water having TDS levels of 50 mg/litre or less does not contain adequate minerals necessary for nourishing the body and drinking this water could do more harm than good.
What is the relationship between TDS in water and hardness of water?
Hardness is a measure of calcium and magnesium salts in water whereas TDS is a measure of total dissolved solids. It can be organic and inorganic solids.
How do you remove TDS from water?
Reverse osmosis is one procedure for reducing TDS levels in the water. You have a variety of water purifiers available in the market that can do this process for you. They do not eliminate TDS completely, but ensure that the output is acceptable for consumption. There is a flip side to this argument. Reverse osmosis can also remove essential calcium and magnesium salts; however, the latest RO water purifiers come with technology which does not eliminate these essential minerals while purifying drinking water.
Is TDS in water good or bad?
We have seen various aspects of TDS in water. The acceptability levels and palatability quotient have their importance. However, the basic question remains, Is TDS in water good or bad?
To put in very simple terms, Zero TDS is not good for health. Similarly, higher levels of TDS are extremely harmful. You need to maintain the perfect balance. You cannot expect the common individual to carry the TDS meter in hand at all times to check the TDS levels. The best way is to trust out human instincts.
You can taste the water. If it is salty or unpleasant, you conclude that TDS levels are high. If the water appears tasteless or bland like you have in distilled water, the TDS levels are low.
TDS – A Brief Recap
- TDS comprises of organic and inorganic salts.
- Source of TDS is natural and manmade.
- Water with TDS up to 500 mg/litre is acceptable for drinking.
- TDS levels below 100 mg/litre do not contain requisite minerals.
Conclusion
Whether we like it or not, TDS in water is inevitable. You have the acceptability levels to adhere to as mentioned in the drinking water TDS chart above. TDS is not as bad as many people think it to be. It is absolutely safe to drink water with a normal TDS level. If TDS is alarmingly high, use RO water purifiers to regulate it.