I'm sure this isn't the answer you are looking for, but a lot of the health impacts will have to do with the type of contamination and the concentration. I've seen some cities and states start to adopt a surface water WQI. Here is a link to one: http://grcity.us/enterprise-services/Environment-Services/Documents/1269_WQI%20river%20run%20and%20summary_2009%20v2.pdf. This has more to do with the recreational value and aquatic life.

Yes. But the methodology can not be generalised and to be exclusively based on the sources of water

Dear Adil,

I agree with Dr. Vahid - your question is indistinct. See, by computation of WQI, you can classify the quality of water (say for drinking purposes) as Excellent, Very good, Good, Poor, Very Poor etc.

No doubt poor, very poor waters have some health effects. Now what type of health effects - that depends on the contents of various inorganic and organic constituents. The excess content of any constituent (above the permissible limit) is definitely harmful for health. The literature regarding health effects is available in the public domain. You can also consult the drinking water standards, like WHO, BIS etc.

Best wishes

I also support Dr Vahid's suggestion

asit sir ,

i acknowledge your answer but i was curious to know that there must be some effects on human body due to consumption of poor ,very poor and unsuitable water quality(reported by any paper or book)

i was more interested in piece of studies which must have conducted such experiments or have reported the ill effects .

We experience choking ,coughing,nausea, bronchitis, intense mucous formation and even asthmatic attacks during high air pollution episodes so referring to that context am interested in knowing the effects on the body due to polluted water consumption as reported via WQI( if there is such evidence)

Dear Adil,

" ........effects on human body due to consumption of poor ,very poor and unsuitable water quality" --- Yes, there will be effects on human body. I have already mentioned.

Adil, you want to know something - but what? This is not clear in your question.

Best wishes

sir

As u must be aware of AQI , the color code relates to the severity of pollution and this severity correlates to the health hazards.

in a similar context , what will be the effects on human body with deteriorating drinking water quality.

Take this example :

Good (0–50) None

Moderate (51–100*) Unusually sensitive people should consider reducing prolonged or heavy outdoor exertion. Unhealthy for Sensitive Groups

(101–150) : People with lung disease, such as asthma • Children and older adults •People who are active outdoors Unhealthy

(151–200) : People with lung disease, such as asthma • Children and older adults •People who are active outdoors Everyone else should limit prolonged outdoor exertion. Very Unhealthy

(201–300) : People with lung disease, such as asthma • Children and older adults •People who are active outdoors Everyone else should limit outdoor exertion

"I am looking for something like this based on WQI "

Dear Adil,

This is the classification based on AQI and related health effects.

Probably, there is no such classification with WQI. But, I think it can be done for a particular area and specific use (say drinking).

Because, the water quality standard varies according to the type of uses (drinking, domestic, irrigation, industrial etc). Moreover, the criteria of ‘acceptable water quality’ varies from region to region. The criteria also changes with time depending upon the prevailing conditions.

So, consider a particular area, and particular standard and specific use (drinking). Then classify the water based on WQI - Now as I told earlier, identify the contaminants responsible for deterioration of water quality - correlate with the health effects and try to explain the same relating different classes (WQI based).

Hope, you have understood. So, try now. It will be a good work.

Best wishes

Respected Asit Kumar Batabyal has provided an in depth description of your question. I will also like to add some points. In calculation of WQI we use concentration of major cations and anions. One of the drawback of WQI is that it tells you about the water quality i.e., good or poor but it does not explains the parameters that is responsible to make it poor in quality (except you consider the intermediate step).

Now let us say your water have high Fluoride but your other cations and anions are within permissible limits. there is every possibility that you will get WQI index as GOOD. So it is very difficult to predict the health issue related with each WQI category.

If you give equal importance to all the cations and anions individually rather than an cumulative WQI score, you can achieve what you desire.

You should come up with some technique that will indicate that parameters that are above permissible limits and suggest you the associated disease

Dear Raju,

Thanks for your comments.

Note this - "..........high Fluoride but your other cations and anions are within permissible limits. there is every possibility that you will get WQI index as GOOD" .

It is not probably true. It depends on the the weight you are assigning to each analyzed parameter. The assigning weight is done based on the degree of heath effects. Here, for fluoride, you have to assign highest weight, say 5 and rest all 4 to 1. Now, compute and see the results.

Best wishes