What's in your drinking water?

Water contains naturally occurring compounds such as lead and arsenic among others. How harmful are these and what is the level of contamination we are exposed to?
19 Jul 2013
0 mins read
Water quality in India Source UNICEF Repository
Water quality in India Source UNICEF Repository

Both rural and urban India are faced with water problems. People do not have access to good quality, safe drinking water. The source for most drinking water is either rivers or underground aquifers (wells). Since water can dissolve just about anything that it comes into contact with long enough, often the groundwater we get isn’t pure.

It could contain naturally occurring lead, arsenic, mercury, radium, chloride, iron and copper compounds dissolved in it. Most of these aren't harmful when consumed in small quantities.  But when the levels go higher than the prescribed amounts, it could be harmful and sometimes, even fatal. Let’s analyse the effects of each of these compounds on our health and understand from the available data which states in India are susceptible to which types of contamination.


Iron, which is seldom found in concentrations greater than 10 milligrams per litre (mg/L) or 10 parts per million can be a troublesome chemical in drinking water. Corrosion of pipes is a common reason why iron is found in drinking water. As little as 0.3 mg/L concentration of iron can make the water appear brown. A laboratory analysis of the water sample can tell you the extent of your problem.

Top 5 iron-affected states in India

The best way to treat this is to use aeration/ filtration or chlorination techniques. Chlorination is the process of adding the element chlorine to the water to make it fit for human consumption. Assam has been reported to have highest concentration of iron in water which is up to 18.85 mg/L.

Top 5 arsenic-affected states in India
Arsenic is a semi-metal found in various foods and mostly in groundwater. Elevated levels of arsenic lead to metabolism failure in the body causing severe heart diseases, night blindness, cancer and even diabetes. A study conducted by USAtoday.com states that around 70 countries are affected by arsenic poisoning from groundwater. Assam and West Bengal have high concentrations up to 2.4 mg/L and 1.83 mg/L respectively. 
Chlorine and Fluoride
Chlorine and fluoride are added to water to kill pathogens, which are disease producing agents. An excess amount of chlorine in the water causes a problem because it leaves behind a residue. This “residual amount”, when consumed, reacts inside the stomach and damages some cells of the organs.
Fluoride is added in water just to prevent cavities, whether you have cavities or not! An excess amount of fluoride in water causes tooth discoloration forming yellow or brown pits and patches on teeth. Long term high exposure (more than 4 ppm) to fluoride may also result in bone spurs and birth defects. Rajasthan and Assam have the highest concentrations of these. 
Nitrate, a naturally occurring form of nitrogen, is found in the soil. It is required in large quantities to sustain high crop yields. A tasteless, colourless and odourless compound, you cannot detect it unless your water is chemically analysed. If you drink water from a private well, get a qualified laboratory to test it yearly. Times of India reported, “Dental and spine-related ailments are showing up in many cities and villages of Karnataka due to increasing levels of Nitrate concentration in drinking water.”
Sewage treatment capacity of states in India
The major cause of increasing nitrate content is open sewage disposal and the use of nitrogen fertilizers. Since rural sanitation in the country is poor, the presence of nitrates in water is evident of such contamination. Proper sewage treatment including contaminants and recycling of waste water to reuse it for various uses like, gardening, toilet flushing and car washing is necessary to keep these levels down. Currently Maharashtra and Uttar Pradesh have the highest sewage treatment capacity in India in Class I cities. 
From the above analysis, we can see the extent of contamination that we are exposed to. Here are some safeguards that we can take to get clean drinking wate.
  • Water supply protection is most effective before contamination occurs. Surface water must never be allowed to flow down in the well. Rainwater and runaway water should be sloped out of a water body. A minimum of 300 feet distance must be maintained between sewage disposal and water supply areas. 
  • Also, it is important to locate and eliminate the source of the contamination. For example, lead and iron contamination can be eliminated by replacing pipes, fittings and fixtures. 
  • New sources for wate spply should be developed in case the existing supply is extensively contaminated with nitrate, salt, pesticides and other chemicals. 
  • Lastly, water must be treated to remove possible disinfectants and chemicals.
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