Water Quality Testing
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Introduction
Water is a chemical compound that contains two hydrogen atoms and one oxygen atom. The term water typically refers to the compound's liquid state. The solid phase is referred to as ice, and the gas phase is referred to as steam. Water can also form a supercritical fluid under certain conditions. Oxidane is another name for it. In chemistry, oxidane is only used as the mononuclear parent hydride to name water derivatives. Because of its polarity and high dielectric constant, water is a universal solvent. Acids, alcohols, and many salts dissolve well in water because they are polar and ionic. (1)
Distribution of water resources on earth
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Water Quality
The suitability of water for various uses is referred to as water quality and depends on its physical, chemical, biological, and organoleptic (taste-related) characteristics. Understanding and measuring water quality is particularly crucial because it directly affects human consumption and health, industrial and domestic use, and the environment. Water quality enforcement standards are set by laws like the EU Drinking Water Directive and regulatory bodies like the US Environmental Protection Agency (EPA), with local governments serving as the primary enforcers worldwide. (3,4,5)
Three types of water quality parameters are measured. Physical, chemical, and biological/microbiological parameters are among them.
Physical parameters of water quality: Physical parameters are those determined by the senses of sight, smell, taste, and touch. Temperature, colour, taste and odour, turbidity, and dissolved solids content are examples of physical parameters.
Chemical parameters of water quality: Chemical parameters of water quality are measurements of characteristics that reflect the environment with which water comes into contact. These chemical parameters can assess pH, hardness, dissolved oxygen levels, biochemical oxygen demand (BOD), chemical oxygen demand (COD), and levels of radioactive substances, toxic organic and inorganic substances, sulphate, nitrogen, fluoride, iron, manganese, copper, and zinc.
Biological parameters of water quality: Biological parameters of water quality are measurements of the number of bacteria, algae, viruses, and protozoa found in water.
Both anthropogenic activities and natural factors have an impact on water quality. These are a few of the elements that have an impact on water quality..
- Atmospheric pollution
- Runoff
- Erosion and Sedimentation
Water Quality and Human Health: Poor quality potable, domestic, or recreational water, as a result of contamination, can cause human illness. Drinking contaminated water contributes significantly to the global burden of disease in the form of diarrhoea, cholera, dysentery, hepatitis A, typhoid, and polio. Human risk arises from chemicals like pesticides, heavy metals, and solvents contaminating water sources. Blood, lung, liver, kidney, and urinary bladder cancers can all be made more likely by long-term exposure to heavy metals like arsenic, chromium, lead, mercury, and cadmium.
Effects of Water Quality on the Environment: Water contamination harms the environment and the flora and fauna that depend on it. The biological functions of plants and animals can be killed, damaged, or interfered with by contamination such as oil spills, radioactive leaks, garbage, chemical leaks, and many other types.
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Specifications and Standards
Indian Standard Specifications for Drinking Water (IS: 10500)
|
S.NO. |
Parameter |
Requirement desirable Limit |
Remarks |
|
1. |
Colour |
5 |
May be extended up to 50 if toxic substances are suspected |
|
2. |
Turbidity |
10 |
May be relaxed up to 25 in the absence of alternate |
|
3. |
pH |
6.5 to 8.5 |
May be relaxed up to 9.2 in the absence |
|
4. |
Total Hardness |
300 |
May be extended up to 600 |
|
5. |
Calcium as Ca |
75 |
May be extended up to 200 |
|
6. |
Magnesium as Mg |
30 |
May be extended up to 100 |
|
7. |
Copper as Cu |
0.05 |
May be relaxed up to 1.5 |
|
8. |
Iron |
0.3 |
May be extended up to 1 |
|
9. |
Manganese |
0.1 |
May be extended up to 0.5 |
|
10. |
Chlorides |
250 |
May be extended up to 1000 |
|
11. |
Sulphates |
150 |
May be extended up to 400 |
|
12. |
Nitrates |
45 |
No relaxation |
|
13. |
Fluoride |
0.6 to 1.2 |
If the limit is below 0.6 water should be rejected, Max. Limit is extended to 1.5 |
|
14. |
Phenols |
0.001 |
May be relaxed up to 0.002 |
|
15. |
Mercury |
0.001 |
No relaxation |
|
16. |
Cadmium |
0.01 |
No relaxation |
|
17. |
Selenium |
0.01 |
No relaxation |
|
18. |
Arsenic |
0.05 |
No relaxation |
|
19. |
Cyanide |
0.05 |
No relaxation |
|
20. |
Lead |
0.1 |
No relaxation |
|
21. |
Zinc |
5.0 |
May be extended up to 10.0 |
|
22. |
Anionic detergents (MBAS) |
0.2 |
May be relaxed up to 1 |
|
23. |
Chromium as Cr+6 |
0.05 |
No relaxation |
|
24. |
Poly nuclear aromatic Hydrocarbons |
-- |
-- |
|
25. |
Mineral Oil |
0.01 |
May be relaxed up to 0.03 |
|
26. |
Residual free Chlorine |
0.2 |
Applicable only when water is chlorinated |
|
27. |
Pesticides |
Absent |
-- |
Bacteriological Quality of Drinking Water
|
S.NO. |
Organism |
Requirement |
|
1 |
All water intended for drinking: a) E. coli or thermotolerant coliform bacteria |
Shall not be detectable in any 100 ml sample |
|
2 |
Treated water entering the distribution system: a) E. coli or thermotolerant coliform bacteria
b) Total coliform bacteria |
Shall not be detectable in any 100 ml sample
Shall not be detectable in any 100 ml sample |
|
3 |
Treated water in the distribution system: a) E. coli or thermotolerant coliform bacteria
b) Total coliform bacteria |
Shall not be detectable in any 100 ml sample
Shall not be detectable in any 100 ml sample |
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Eurofins services
The professionals at Eurofins Analytical water testing labs believe that the quality of water bodies is extremely important and that accurate water quality is required for one's needs. The analysis services provided are in accordance with National and International Standard testing and analysis guidelines.
The types of water tested includes-
- Drinking water as per IS 10500
- Packaged Drinking Water as per IS 14543
- Natural Mineral Water as per IS 13428
- Process Water IS 4251
- Reverse Osmosis Water
- Water testing as per WHO
- Waste Water
- ETP, STP
- Surface and ground water for portability
- Water for construction
- Reagent grade water
- Water for processed food industry
- Irrigation process
- Swimming pool water
- Leachate Water
References
- https://www.thoughtco.com/definition-of-water-in-chemistry-605946
- http://sncyear7geography.weebly.com/distribution-of-water.html
- https://echo2.epfl.ch/VICAIRE/mod_2/chapt_2/main.htm
- https://svalbardi.com/blogs/water/quality
- https://sensorex.com/2021/09/20/three-main-types-of-water-quality
- http://cgwb.gov.in/Documents/WQ-standards.pdf
- https://www.eurofins.in/food-testing/industries/water-testing/
