Fluorosis in Yavatmal by abstraks

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									Fluorosis in Yavatmal

Fluoride Action Network
January 07, 2002

Fluorosis in Yavatmal

by Anuradha Kumar

In mid-2000, as incidents of severe fluorosis in a village in Yavatmal district came
to light, the Maharashtra government declared a special Rs 200 crore package
for safe drinking water in tribal-dominated areas. The incidents had sparked off a
major uproar and in an unprecedented move, the National Human Rights
Commission too had passed strictures against the government asking it for a
detailed report on the matter and threatening suo moto action if it failed to
comply.

In Yavatmal, bordering Andhra Pradesh, incidence of fluorosis has been rising in
recent years along side the mindless extraction of groundwater. Lack of rainfall
has meant that the district is largely dependent on groundwater, both for irrigation
and drinking water requirements. Incessant digging of borewells has given rise to
sharp rise in the fluoride concentration in the ground water. Fluorides and other
dissolved salts in drinking water have exceeded the safe limit in the past two
decades. A high intake of fluoride (>1.5 mg/l) in drinking water over a prolonged
period is known to cause damage to the enamel of the teeth, and eventually
results in skeletal complications leading to fluorosis. A progressively increasing
proportion of the population in Yavatmal including undernourished children is
now infected with fluorosis.

Other areas with high fluoride content in groundwater as per the Nagpur based
Central Ground Water Board (CGWB) periodic reports are Bhandara,
Chandrapur, Nanded and Aurangabad.

Extent of the problem in India

Fluorine occurs in rocks in the form of fluoride-bearing minerals like fluorite and
fluoroapatite. India has large resources of these minerals. In such areas,
groundwater drawn through wells, hand-pumps and especially tube-wells is likely
to contain excess fluoride due to the dissolution of fluoride from the fluoride
bearing minerals. The problem of excess fluorosis in groundwater was detected
in many states in India as early as the 1930s. Till 1999, as many as 17 states
have been identified with the problem of excess fluoride in groundwater
resources.

Rajasthan and Andhra Pradesh are the most severely affected states. Rural
populations, which depend mainly on groundwater for their drinking water supply
are the worst affected. Vulnerability to fluorosis is higher if the nutritional status is
poor-malnourished children, pregnant women or lactating mothers are especially
vulnerable.

To combat fluorosis, the preferred option is to find a supply of safe drinking water
with safe fluoride levels. But where access to safe water is already limited, de-
fluoridation may be the only solution. De-fluoridation of drinking water using
domestic water filters, has been found to be by and large the most effective way
to prevent excessive fluoride intake in fluorosis endemic villages. However,
removal of excessive fluoride from drinking water is difficult and expensive. The
methods include - use of bone charcoal, contact precipitation, use of Nalgonda or
activated aluminae. Since all methods produce a sludge with very high
concentration of fluoride that has to be disposed of, it is advocated that only
water for drinking and cooking purposes should be treated, particularly in
developing countries.

Two methods of de-fluoridation are currently in use.

a) The Nalgonda technique, under which calculated amounts of alum, lime and
bleaching water are added to pre-treated water and the mixture is stirred.
Fluorides are absorbed by the aluminium hydroxide complex compounds and
settle as sludge at the bottom of reactors. However to ensure for optimum
fluoride removal, alum and lime need to be added in certain proportions and a
trained operator and chemist are required to operate this filter.

b) As against this, de-fluoridation plants based on activated aluminae are very
simple to operate and even as recently demonstrated by villagers in Rajasthan’s
Tonk district, local people themselves can handle these filters with some initial
training. The only problem with the mass utilisation of these filters is that the cost
of activated aluminae is comparatively high at about Rs 130 per kg.

Active Aluminae in Treating Fluorosis

UNICEF has been working closely with the Indian government of India and other
NGOs to implement specific fluorosis mitigation programmes – initiated
specifically at the grassroot level. A number of demonstration projects were
initiated in fluorosis affected states in cooperation with state governments,
panchayats and community groups and NGOs - Anantapur in Andhra Pradesh,
Dungarpur and Tonk in Rajasthan, Kanpur Dehat in Uttar Pradesh and
Chandrapur in Maharashtra.

In these areas, epidemiological surveys were conducted with help of doctors to
understand the magnitude of the problem as well as to provide basic data on the
health status of families in the area. This information is vital for subsequent
impact assessment studies. In the project villages, testing of all drinking water
sources was done. UNICEF facilitated the innovation of a Domestic De-
fluoridation Unit (DDU) which used activated aluminae to remove excess fluoride
from drinking water. Promotional camps highlighting the use, maintenance and
regeneration aspects of domestic de-fluoridation units are held at village level.

Recently, the project saw a successful beginning in Rajasthan’s Tonk district and
will be replicated in other areas too where the studies were carried out. In these
Tonk villages, fluorosis affected villagers have now been able to come to terms
with the problem. The solution has been community participation - NGOs have
trained the villagers to filter the water of excessive fluoride through a simple
chemical treatment. Although the method is not all that simple, villagers have
learnt to determine the percentage of fluoride in drinking water by treating the
water with a chemical compound called zirconilered. Then the excess fluoride
from the water is removed by passing it through a chemical called activated
aluminae.

The UNICEF and a couple of local NGOs are focussing on setting up community
as well as household de-fluoridation projects in these areas. Initially the UNICEF
is providing most of the fund required in buying the activated aluminae to set up
de-fluoridation units. The rest of the money is to be contributed by the community
or owner of particular households. The maintenance is the owner’s responsibility.

Even regeneration of activated aluminae which becomes useless after being
used for de-fluoridation for five to six months, is being done by the villagers
themselves by using caustic soda/potash and sulphuric acid. UNICEFF provides
part of the initial fund to set up at least one regeneration unit per village and
responsibility is entrusted to a village representative seen to have acquired some
degree of expertise in handling the process. The NGOs and the UNICEF believe
that domestic as well as community de-fluoridation of water will be sustained
here as the community has shown tremendous interest in it.
The involvement of local community in fighting fluorosis holds out much hope.
Earlier government efforts failed because they did not educate communities and
did not relate fluorosis, viewed as a public health issue, to the environment.

Nalgonda Technique

The older Nalgonda technique was developed by the National Environmental
Engineering Research Institute (NEERI) in Nagpur that has been involved in
research and development activities on de-fluoridation of water since the 1960s.
It was at Nalgonda in Andhra Pradesh that the first community de-fluoridation
plant for removal of fluoride from drinking water was constructed in Nalgonda’s
Kathri town, and hence the technology now in use worldwide also came to be
known as the Nalgonda technique.

In this technology, raw water is mixed with adequate lime and alum. But it is
important that the doses of alum and lime are determined after assessing the
fluoride content and alkalinity of water. The alum solution is added after the
addition of lime, stirred gently for 10 minutes and the flocs formed are allowed to
settle. This process of floc formation and settling requires an hour. In rural areas
where the people practice domestic de-fluoridation, the advice given is to mix the
water with lime and alum and leave it overnight, so that the next morning the
clean supernatant is decanted for use and is safe for consumption. In the
Nalgonda technique, besides fluoride, turbidity, colour, odour, pesticides and
organic substances, if any, are also removed. Bacterial contamination is also
reduced significantly.

The merit of the technique is that it can be used at both the domestic and
community levels. Operations are possible manually. NEERI also developed a
variety of designs and models for use in different locations. But the major
concern with the lime and alum technology is that if the dose of alum is not
adhered to, there could be a possibility of excess aluminium contaminating the
water. Due to the concern shown regarding possible health hazards, aluminium-
caused alternative coagulants and coagulant aids are now being recommended.

Researchers in Nagpur University now suggest that bauxite, an abundantly
available aluminium ore, could form a cheap substitute agent for removal of
excess fluoride from drinking water. Bauxite can be used as a defluorinating
agent in domestic water filters in place of activated aluminae, which is more
expensive.

About eight samples of bauxite from different ore deposits all over the country
were tested and found to be suitable as a cheaper substitute for de-fluoridation of
drinking water. It was also found that after its use as medium for fluoride removal,
bauxite still retains its use as ore of aluminium, with certain value addition. The
rejected bauxite from de-fluoridation units can also be effectively used for
aluminium metallurgy. Bauxite also happens to be a natural resource that is
widely available in almost all regions of the country.

Health Education

Besides de-fluoridation, health education regarding appropriate use of fluorides is
a must. It is now established that fluorosis is restricted to rural areas where the
populace does not have access to treated drinking water. Among the rural
populace, the tribals are found to be more severely affected, pointing that
economic status and dietary habits may have a major role to play.

According to A N Deshmukh of Nagpur university’s geology department who was
once part of the UNICEF project at Chandrapur, most of the fluorosis victims
were found to have a very poor dietary intake, particularly with regard to calcium
rich food (milk and other dairy products). Calcium is known to nullify the effect of
fluoride in body, as it has the capability to absorb fluoride ions. Calcium
supplementation -- through calcium tablets or through calcium rich food -- has
thus been suggested as one of the corrective measures. Mothers in affected
areas should be encouraged to breastfeed since breast milk is usually low in
fluoride.

It is also known that fluorosis, in its severe forms, is mostly restricted to a
particular climate zone in the world -- the areas with semi-arid tropical conditions.
In these areas, the consumption of drinking water is high and the populace is
thus more vulnerable to the disease as compared to their counterparts in colder
areas with low consumption of water, though the fluoride content of water in both
the areas may be the same.

See also:
Recent reports of fluorosis in India...



About the Author: Anuradha Kumar is a journalist based in Bombay, India. She is
currently on a fellowship with the Delhi-based Centre for Science and Environment,
where she is focusing on water management and conservation issues.

Source: http://www2.fluoridealert.org/Alert/India/Fluorosis-in-Yavatmal

								
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