Development of Drinking Water Quality Standards in...
Transcript of Development of Drinking Water Quality Standards in...
Development of Drinking Water Quality Standards in Jordan
Dr. Muna Hindiyeh Water & Environmental Engineering Water and Wastewater Microbiology
Amman/Jordan Email: [email protected]
WHO Guidelines and National Standards for Drinking Water Quality
• The evolution of directives and regulations
related to public health matters is not controlled
only by toxicological or epidemiological findings.
· Economic interest,
· Socio-cultural characteristics,
· Hygiene practices,
· Public awareness and
. Sensitivity and technological development
The purpose of developing regulations
To establish limits related to specific practices, which will minimize detrimental effects without affecting the benefits.
These limits have no absolute value, nor can they be definitely established. They will vary with scientific development, economic constraints and status as well as with the changing tendencies towards acceptance or rejection of practices affecting the cultural values of a society.
• Background and guidance to governments for making
risk management decisions related to the protection of
public health and to the preservation of the environment;
also
• Provide common background on which national or
regional standards can be derived.
• They have an advisory nature based on the
state-of-the-art in scientific research and
epidemiological findings and are not to be confused with
legal standards.
WHO guidelines produced to provide :
It must be stressed that guidelines are not intended for absolute
and direct application in every country.
National Standards: are guidelines fixed by law in countries
after being adapted to their national priorities and taking into
account their:
· Economic
· Technical,
· Social
· Cultural, and
. Political situation.
At any time they can be changed or modified whenever new
scientific evidence becomes available.
• An epidemiological study conducted in Sudan did not reveal
any harmful effects at concentrations of nitrate as high as
226 mg/l.
• Sudanese children depend highly on breast feeding for a
minimum period of 18 months, and later on cows and goats
milk. This specific cultural custom of the country, added into
consideration that nitrate can only be removed by costly ion
exchange systems, led the Sudanese authorities to choose a
standard value of 50 mg/l (as N), While WHO has proposed
a guideline value of 10 mg/l (as N) for nitrate in drinking
water.
There is no evidence of adverse physiological reactions at
high levels of TDS, but water becomes unpalatable and may
lead to corrosion or incrustation in water distribution
systems. For this reason the WHO guideline value for TDS
was set at a limit of 1000 mg/l.
However, due to difficulties in finding sources with lower
salinity and the difficulties associated with desalination
systems, the Sudanese authorities adopted standard value of
5000 mg/l of TDS, the maximum level above which water
becomes undrinkable.
Jordan has also followed the same criteria for establishing
Drinking Water Quality Standards. Several parameters {such
as nitrate, sulphate, sodium, chloride, mercury, nickel,
barium, boron, zinc, manganese and iron (JS 286/2001)}
have been given numerical values above the guideline values
prescribed by WHO (1998).
JS 286/2008: Ba, B, Ni, Endrin, 2,4-D, DDT, and Xylene
have been given numerical values above the guideline values
prescribed by WHO (2004).
But unfortunately without conducting any scientific research
and/or epidemiological study concerning risk affecting
health.
Jordanian Drinking Water Quality Standard DW Quality
No. Parameter Unit 286/2001 WHO Guidelines 1997
max. allowable limit max. allowable limit in
case of no other better
source is available
1 NO3 mg/l 50 70 50
2 SO4 mg/l 200 500 250
3 Cl mg/l 200 500 250
4 Na mg/l 200 400 200
5 Fe mg/l 0.3 1.0 0.3
6 B mg/l 2.0 2.0 0.3
7 Mn mg/l 0.1 0.2 0.1
8 Zn mg/l 3 5 3
9 Ni mg/l 0.07 - 0.02
10 Ba mg/l 1.5 - 0.7
11 Hg mg/l 0.002 - 0.001
12 Fungus Count/
100 ml
Dropped out Taste & odor
13 Algae Count Dropped out Taste & odor
Evolution of Jordanian drinking water quality standards 286/ 1982, 1988, 1997 and 2001
Parameter 1982 1988 1990* 1997* 2001
Max. allowable limit
Coliform count /100 ml 10 < 2.2 < 2.2 < 1.1 < 1.1
Thermotolerant coliform count/100
ml
Zero Zero Zero Zero Zero
Free-living organisms
Algae
Fungus
-
-
-
Zero
Zero
Zero
Zero
Zero
Zero
Zero
Zero
Zero
1 alive nematode
-
-
Intestinal nematode - Zero Zero Zero Zero
Pathogenic Protozoa - Zero Zero Zero Zero
THBC / 1 ml 99 1000 1000 - -
NO3 mg/l 15-40 45-50 45-70 50-70 50-70
NO2 mg/l - - - 2 2
Ni mg/l 0.05-0.1 0.05-0.1 0.05-0.1 0.02 0.07
Cd mg/l 0.01 0.005 0.005 0.003 0.003
Pb mg/l 0.05 0.05 0.05 0.01 0.01
As mg/l 0.05 0.05 0.05 0.01 0.01
Hg mg/l 0.005 0.001 0.001 0.002 0.002
CN mg/l 0.02 0.1 0.1 0.07 0.07
THM mg/l - - - 0.15 0.15
* If coliform count only detected, then fecal streptococcus and clostridium has to be tested.
- not mentioned or dropped out
On the other hand, many industrialized countries, increasingly
concerned by risks affecting health, have adopted national standards
for drinking water quality which are more restrictive than WHO
guidelines.
Since they can afford advanced treatment systems as well as
sophisticated laboratories for monitoring and surveillance.
In Jordan Standard for Drinking Water Quality (286/2008) also
showed more restrictive limits than WHO guideline only for
aluminium, antimony, manganese, nitrite and copper.
National Standards
Comparisons & Contradictions
• Updating Jordanian Standard (JS 286/2008) for Drinking Water Quality had been done 6 times within 26 years (established during 1982, and updated in 1988, 1990, 1997, 2001, and 2008).
• While Jordanian Standard (JS 200/1987) for natural mineral water established in 1987, had been updated two times only 2001 and 2009. Contradictions in the limit values for several parameters between both standards were shown in the following table, which seem that drinking water quality standard more restrictive than the natural mineral water standard were infants, elderly people and patients depend on it for drinking.
No. Parameter Unit Jordanian
DW Quality
Standard
286/2001
DW Quality
WHO
Guidelines
1997
Jordanian
Natural
Mineral
Waters
Standards
200/1987
Jordanian Natural
Mineral Waters
Standards 200/2001
1 NO3 mg/l 50-70 50 45 45
2 Mn mg/l 0.1-0.2 0.1 2.0 0.1
3 Ni mg/l 0.07 0.02 - 0.02
4 As mg/l 0.01 0.01 0.05 0.01
5 Pb mg/l 0.01 0.01 0.05 0.01
6 Cd mg/l 0.003 0.003 0.01 0.003
7 Ba mg/l 1.5 0.7 1.0 1.0
8 Zn mg/l 3-5 3.0 5.0 -
9 CN mg/l 0.07 0.07 0.01 0.05
10 B mg/l 2 0.3 0.3 5
11 Free living
Nematodes
Count/l 1 alive Should be
Absent
- -
Mineral Water JS 200/2009
WHO Drinking Water Quality
2011
WHO Drinking Water Quality
2004
Jordanian Drinking Water
JS 286/2008
Parameter
˃ 1000 - 600-1000 1000 TDS
- - 500 500 TH
- - - 0.2 MBAS
- - - 0.2 NH4
- - 0.1-0.2 0.1 Al
- - - 1.0 Fe
- - 3.0 4.0 Zn
- - 200 200 Na
- - 250 500 Cl
˃ 600 - 250 500 SO4
5 2.4 0.5 1.0 B
0.5 - 0.4 0.1 Mn
- - 0.07 0.07 Mo
50 50 50 50 NO3
There are no limits assigned for Organic pollutants as DDT, Lindane, Endrin, ..etc, and Disinfectant by products as THM’s in the JS Mineral Water 200/2009 and Desalinated Water 1528/2010.
Jordanian Drinking Water JS 286/2008
Mineral Water JS 200/2009
Bottled Water JS 1214/2009
Parameter (mg/l)
500 - - TH
0.2 - - NH4
500 - - Cl
1.0 5 0.3 B
500 ˃ 600 100 SO4
0.07 - - Mo
50 50 15 NO3
0.01
0.01 0.05 Se
0.001 0.001 0.002 Hg
0.15 - 0.035 THM
Organic Pollutants (µg/l)
Jordanian Drinking Water
JS 286/2008
WHO Drinking Water Quality
2004
Mineral Water JS 200/2009
Bottled Water JS 1214/2009
Parameter
2.0 0.6 - 2.0 Endrin
90 30 - 90 2, 4 D
2.0 1.0 - 2.0 DDT
700 500 - 700 Xylene
10 10 - 10 Benzene
There are no limits assigned for alpha (α) and (β) radiation in the JS Bottled Water 1214/2009 and Desalinated Water 1528/2010.
While Tap and Mineral drinking water standards for
• alpha (α) = 0.5 Bq/l
• (β) radiation= 1 Bq/l
Microbiological standards for Water And Foods
• Practitioners in the water industry are familiar with the bacteriological requirements but not really with those for foods.
• European directives govern the bacteriological quality of most food, and many practioners who were brought up with zero coliform per 100 ml of drinking water would be surprised by the apparent laxity of microbiological standards for foods.
European Standards
• EC Minced Meat Directives: – Minced meat: 150 000 E. coli per 100 gram.
– Meat preparations: 1 500 000 E. coli per 100 gram.
• EC Milk Directive 92/46/EEC: – Soft cheese : 10 000 000 Total coliform per 100 gram.
– Hard cheese: 10 000 000 E. coli per 100 gram.
– Ice cream 10 000 Total coliform per 100 gram.
Drinking Water Quality and Food Standards
Whilst in the subject of food, the coliform and fecal coliform
counts that permissible in the FAO Standards (1992) were very high comparing with absence in drinking water.
Beyond doubt, the presence of such type of bacteria in water or food samples means its subject to faecal pollution; and that, as a result, it may contain bacterial and/or other pathogens which might initiate disease in anyone consume it.
The permissible values for coliform counts in 100 g
of food that allowed for human consumption as
follows:
Dried milk 10 000
Pasteurized liquid, frozen and
dried egg products 100 000
Coated or filled dried
shelf stable biscuits 100
The following food is allowed for human consumption with fecal
coliform counts per 100 g as follows:
Frozen vegetables and fruits 100 000
Dried vegetables 100 000
Cooked, chilled and
frozen fish, crab etc. 50 000
In the Jordanian Standards the coliform counts per 100 g are
permissible for certain type of foods as follows:
Infants milk and food (JS 472/1989, 2003, 2008) 1000
Pasteurized milk (JS 538/1987, 2003) 1000
Cream (JS430/1985, 2001, 2010) 1000
Milk and Cream powder (JS 121, 2008) 1000
JS 25 and 24/2009 for Cucumber and Tomato respectively no limits had been specified for coliform counts. No Jordanian Standards for Lettuce.
“New Jordanian Regualtions for Ready-to-eat food”
- JFDA (2011) Ready-to-eat foods are of “acceptable” quality if they contain:
˂ 100 E. coli per gram (i.e. ˂ 104 per 100 gram).
So absence of coliform per 100 ml of drinking water is fine, and
1000 coliform per 100 g of infant food is just acceptable too.
Suddenly, irrigating lettuces or radishes with water containing 1000
fecal coliform per 100 ml doesn’t seem so dreadful.
We actually live in an invisible “sea” of coliform- they are literally
everywhere: finger-tips are a good place to find them.
Conclusion
National drinking water quality standards are expected to meet WHO Guidelines as closely as possible.
However, if local conditions do not allow for the adoption of the recommended numeric values, alternative control measures should be undertaken to avoid the development of adverse health effects.