2nd International Workshop on Fluorosis and Defluoridation of Water
* EnDeCo, Thulevej 16, DK-2860 Søborg, Denmark, E-mail: email@example.com
CRITICAL SUSTAINABILITY PARAMETERS IN DEFLUORIDATION
OF DRINKING WATER
SUMMARY: Experiences from household and community defluoridation projects have
been collected. They are presented in the form of critical parameters that need to be
considered for the success of household defluoridation projects. Parameters are classified in
three groups. Motivation of households seems to be critical since fluorosis is not always
considered as the main problem of concern and improvements are not always visible for a
number of years. Appropriate and cheap technique is always a must in poor villages. Finally
the organisation of supporting functions that may include quality control, technical and
motivating support, as well as general educational initiatives.
Key words: Defluoridation; Water supply projects; Critical parameters; Appropriate technology;
Defluoridation of drinking water in third world countries has generally been
unsuccessful in spite of many attempts to implement projects aiming at provision of
safe drinking water in fluorotic areas. Furthermore, no defluoridation initiatives have
been taken in many areas where fluorosis is prevalent, probably due to lack of
knowledge of appropriate technologies or lack of means to provide all the project
components associated with defluoridation. The difficulties to achieve sustainable
results are illustrated by the fact that very few projects are actually practising
defluoridation at present.
A review has been initiated by the Danish International Development Agency,
Danida, in order to assess practical defluoridation experiences in selected areas and to
identify critical parameters in defluoridation projects. This paper presents the
preliminary findings by the reviewer, based on study visits to defluoridation projects
in India, Sri Lanka and Tanzania, interviews with a number of researchers and
practitioners in the field of defluoridation and experiences expressed in project reports
and scientific papers.
It seems practical to classify the critical parameters into three groups, each of which is
absolutely essential to consider in any defluoridation project:
• Motivation of users.
• Appropriate and economic technique.
• Proper organisational setup.
Basically, defluoridation can be introduced at two organisational levels; as household
defluoridation, carried out by the single households for their own consumption, and as
community defluoridation, carried out for the public in a village, town, sub-village
etc. Experiences with other forms like institutional defluoridation (schools, health
centres etc.) or private defluoridators shared by several households are presently
limited. The specific parameters are in the following grouped in household
defluoridation and community defluoridation.
192 H Breghøj
2nd International Workshop on Fluorosis and Defluoridation of Water; Int. Soc. Fluoride Res.
Defluoridation of drinking water has been implemented in different numbers of
households. The Nalgonda technique, i.e. flocculation with alum and lime, has been
experienced in India and Tanzania. Adsorption in activated alumina columns has
been experienced in India and in crushed brick columns in Sri Lanka. Adsorption in
bone char columns has been experienced in Thailand, Sri Lanka and Tanzania.
Motivation. Motivation of users to actually procure and use an available
defluoridation technique is absolutely essential in household defluoridation. Any of
the selected techniques requires attendance and an extra workload and payment either
daily in case of the Nalgonda technique or (as an example) tri-monthly in the case of
the column adsorption methods. To carry out defluoridation on top of the other
burdens often faced in the regarded countries requires that the "water manager" in the
household, almost always the woman, is properly motivated to do so.
First of all it requires awareness about the advantages of defluoridation, i.e. the
possibility of reducing the skeletal and non-skeletal fluorosis among the family
members. Many villages have only been exposed to fluoride during few years and the
examples of fluorosis are scarce. The awareness has been induced through an
awareness camp, i.e. a public meeting in the village where fluoride's health hazards,
sources of fluoride, the fluoride situation in the village and fluorosis prevention both
through defluoridation and changes in dietary habits is introduced. Use of living
examples of fluorosis victims in the village has been mentioned as effective in raising
the understanding of the seriousness of the matter.
Awareness camps seem to be appropriate for teaching of fluorosis subjects to a large
group in the first instance. It has however been mentioned that sometimes villagers
tend to forget the knowledge with time.1 A large number of villagers are often
illiterate and more used to learn by experience than by teaching. Special attention has
to be paid to the procurement of understandable handouts and perhaps also certain
forms of reminder sessions or continuous information.
It is not always enough to be aware of the consequences to actually act accordingly.
Like the smokers smoke, fully aware of the high risk of lung cancer, some people will
not defluoridate the water even though they have means to do so and they have their
own children as living examples of dental fluorosis victims. This irrational behaviour,
whether attributed to lack of interest, ignorance or laziness, seems to be a general
human character that must be realised.
A commitment to the investment done when the household has paid for the
defluoridator has been mentioned as a driving force to carry out defluoridation. The
feeling of ownership is generally considered as a positive factor in operation and
One parameter that seems to hinder peoples motivation is the lack of viable results,
since fluoride cannot be sensed and reduction in fluorosis prevalence are usually not
seen the first many years. The Unicef supported project in Rajasthan has had success
in making a health survey before introduction of defluoridation and a re-examination
of fluorosis victims three months after defluoridation start. The victims felt a relief in
both skeletal and non-skeletal symptoms. Furthermore an increase in the ability to
make certain movements was measured.2 The understanding of the positive benefits
when the collective results were presented to the community has been judged to be
Critical sustainability parameters in defluoridation of drinking water 193
Editors: Eli Dahi & Joan Maj Nielsen
one of the most important motivating factor in the project. It may for this reason be
much easier to motivate people to carry out household defluoridation in areas with
high fluoride concentrations (≥4-5 mg/L) than in areas with lower fluoride
concentrations (1.5-3 mg/L).
Factors that seem to enhance the motivation to some extent are other improvements in
water quality, experiences like the brick defluoridation seems to cool the water and
bone char may give a better taste. Among other factors that "motivates" is perhaps a
continuous attention of the defluoridation project manager, combined with a
commitment (like a signed contract) to carry out defluoridation for a number of years.
Appropriate and economic technique. Because of the difficulties in motivating
people for defluoridation it is extremely important to choose a technique that is cheap
and which requires only minor workload. At the same time it should be easy to learn
and remember, even for illiterate people. Obviously it should not impart any adverse
taste to the treated water and the maintenance and repair should be easy and
For the Nalgonda technique and other possible methods that need a daily operation it
is important that the operation period is limited to a minimum. It has been
experienced that it is very difficult for a housewife to find 15-20 undisturbed minutes
every day to carry out defluoridation.1 Probably 5 minutes for defluoridation should
be considered as a maximum. This is also sufficient for the Nalgonda technique.3
For the column treatment methods the daily operation is normally negligible. The
hurdle for the proper operation/maintenance is the regeneration or exchange of media,
normally carried out every few months. This is either connected with a relatively
heavy workload (crushing of bricks) or a relatively high investment in regeneration or
new media. The cost may not seem high on a monthly basis, but when 3 months
media has to be paid at one time it may seem overwhelming for a poor household thus
pushing the payment till next month - and yet another month - etc. To reduce
"irrational excuses" replacements and regeneration should be arranged as cheap and
simple as possible.
All the mentioned defluoridation methods can be appropriate as such for household
defluoridation, but proper designs and materials have to be selected. Users have
expressed complaints of heavy manual workloads both in daily defluoridation practise
and during exchange of media. This may, to a certain extent, hinder the success of the
project. Simple procedures / easy operation and durable materials that are easy to
maintain and repair, will be important if not crucial for the success of household
defluoridation, especially where the motivation is not very high.
Safety of handling of chemicals for defluoridation and regeneration should be sought.
Wrong dosage of e.g. alum in the Nalgonda technique may result in inappropriate pH
in the treated water. Thereby fluoride removal will be less, but it is more crucial that
the taste may become offensive and thereby demoralises people from using the
method. Poor taste together with rumours about side effects of the treatment can be
effective in discouraging people from drinking the water.1 Variation in qualities of
e.g. alum and lime may result in different fluoride removals and water qualities.
Special attention has therefore to be paid to the fact that these chemicals are
commercially available in different qualities.
194 H Breghøj
2nd International Workshop on Fluorosis and Defluoridation of Water; Int. Soc. Fluoride Res.
There is at the moment not much experience with self-financing of defluoridation.
The most obvious cost recovery method for household defluoridation would be self-
payment of (at least) operation and maintenance costs. Obviously they should be kept
at a level that people will pay. To meet the poor people’s ability to pay, chemicals can
be subsidised if there is economic basis to do so. That may also prevent people from
buying commercial poor quality chemicals. The defluoridators should also be cheap
enough for people to meet the costs. Otherwise there should be a public funding to
provide or to subsidise the defluoridators.
It is experienced in various projects that defluoridators are in most cases too
expensive to sell for the majority of the population. If no subsidies are available, an
option like installation a tap in a bucket already at use in the household would in
many cases be the only affordable solution. Moreover it has to be realised, that even
methods which are known to be cheap, demand steady extra expenditure for water
and the cost of chemicals, whether paid monthly or biannually, may be a significant
factor of discouragement for many people to continue treating the water. More
experience is needed with respect to people’s willingness to pay, but there is a good
reason to keep costs to a minimum.
Proper organisational set-up. Any defluoridation method would sooner or later need
supply of chemicals for dosage or for regeneration of media and a reliable supply of
spare parts and spare media. It is obvious that these needs can be covered either
through arrangement with the private retailers or through the water authorities. The
system of choice will depend on the local conditions. It is also obvious in case
activated alumina or bone char is used, certain arrangements have to be made in order
to ensure proper regeneration/supply of media.
It has been experienced that when introducing a technique utilising breakable parts, it
is necessary to set up units to carry out minor repair of the households defluoridators.1
That is because the households neither have the skills nor the simple tools to carry out
the repair on their own. In some cases, the households do not give priority to buy even
cheap spare parts or to spend the necessary time to do the repair. Easy access to
technical support (both as adviser and manual support), e.g. a man in every village
that has got specific training, may be needed to keep as many defluoridators as
possible in operation.
In this connection it has also been experienced that people, after some time of
operation, tend to forget procedures and/or to loose interest in the defluoridation. It
may be necessary to ensure a continuous follow up of awareness or motivation among
the households for an extended period of time. Collaboration with community
development NGO's has been suggested and is being tried out in some projects. In the
project using crushed bricks in Sri Lanka it has been decided to follow the
implementation for at least five years. Such a follow up may be required in order for
people to observe better oral health among children and to ensure the sustainability of
the implementations. Organisation of the provision of qualitative test kits for fluoride
measurements based on the alizarin method may be useful for the households to gain
assurance about the efficiency of treatment (motivation).5 However still this method
needs more documentation about its usability in practise as an on/off method.
The preceding applies for the local organisation necessary for maintaining household
defluoridation. The superior water authority needs to play an active role in at least the
control and monitoring functions.
Critical sustainability parameters in defluoridation of drinking water 195
Editors: Eli Dahi & Joan Maj Nielsen
A certain control of, ultimately, the quality of the treated water in the households is
necessary. Frequent sampling of treated water for analysis can be used to point out
problems in operation. The water authorities should carry this out. Other kinds of
water quality assurance will include control of quality of chemicals and control that
these are actually used by the households. Finally the responsible authorities should
control the procedures and guidelines given for defluoridation. The Nalgonda
technique represents a special problem that should be addressed, because the quality
of the alum and lime is critical and so is the dosage of chemicals, that ultimately
needs to be determined for every single water source (at different times of the year)
and every single bucket size.
It may be crucial for a large scale implementation that some functionaries at all levels
of the water supply and health authorities are aware of the fluorosis problem and the
possible means to solve it. Higher levels of administration will only be able to advice
the lower executing levels about the strategies if they themselves are aware of the
fluoride problem and its implications. This would require a general educational
program in the administration.
Finally the water authorities should be the institution that collects the experiences
gained in the particular geographical and cultural environment since no technique will
be applicable the same way in all environments. Together with the health authorities
they have an important role to play in surveying the health (fluorosis) status as a
result of defluoridation programmes.
COMMUNITY PLANT DEFLUORIDATION
Many practitioners as an intermediate solution see household defluoridation until a
more permanent low-fluoride water supply has been established. In fluorotic areas the
permanent water supply may well be based on defluoridation of water in a community
water treatment plant. The reason why community plants are not always introduced in
the first place is higher costs of construction, higher costs of chemicals, especially if
all domestic water should be treated and distributed. Moreover because of problems
in maintaining and paying the O & M costs of a public water treatment plant in areas
where the public management is poor. The following is partly based on village
defluoridation experiences gained in India..4
Motivation. It is presumably easier to motivate people to walk a little longer to fetch
their drinking water than to do the additional work connected with household
defluoridation. They will however need to be informed about fluorosis and the
installed defluoridator. Information meetings by the time of implementation are
therefore necessary. Plants should also be marked clearly with a message like "water
fit for drinking and cooking".
It is rather de-motivating for people if the plant is not functioning as expected. The
plant can be non-functioning in periods because of power cuts or operational
problems (technical breakdowns or lack of chemicals). It can also deliver water of
poor aesthetic quality e.g. because of erroneous dosage of chemicals. Both cases can
lead to rejection by the users and by-pass of the treatment plant.
If the water treatment is functioning, affordable and not too distant, lack of motivation
should not be a problem. There are probably no experiences so far with payment for
defluoridated water and how it effects the users' willingness to use defluoridated
water. Payment will probably lead to a higher demand of service.