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ARSENIC RISK MANAGEMENT:
NEED FOR A COMPREHENSIVE STRATEGY
M.
Asaduzzaman
Arsenic contamination of ground water has emerged as the latest
scourge to haunt Bangladesh. Million upon million of people are
now either already affected by it or about to be affected. They
face the spectre of cancer, internal organ disorder, gangrene
and death. More telling is that many of them, particularly young
women now possibly live as social outcasts.
A
lot of debate is now going on regarding the extent, causes and
mitigation of arsenic toxicity. This is not the place to discuss
any of these in any detail. Interested readers may wish to
consult some of the literature and data that are available on
the Internet, particularly the data made public by the British
Geological Society. My objective here is to question some of the
ways in which the arsenic toxicity is viewed by the authorities
in Bangladesh and the manner in which an integrated strategy
should be worked out.
There are basically two or rather three strands of thought and
action which are going on now. The first one is the
investigation on the spatial extent of As (abbreviation for
arsenic) through the testing of the waters from hand tubewells
and marking them with red and green colour to warn people (red
for danger, green for safe) of the presence of As in water. The
second is the innovations for a cheap, cost-effective method of
purification of water for drinking. The third is popularisation
of some of these two, i.e., testing and purification through
some of the NGOs. These are all important elements of a strategy
to eliminate the risk of arsenic toxicity. Unfortunately, they
are not enough and are all being done on an ad hoc basis. There
are major missing elements in the actions that are being taken
or discussed. There are confusions regarding adaptation and
mitigation of arsenic contamination and there is so far little
by way of a strong political commitment expressed at the highest
level of the Government. It is only the print media which has
played a major role in raising awareness including the National
Community Hospital and some of the NGOs. Below I try to provide
briefly a unified approach towards developing a comprehensive
arsenic risk management strategy (ARMS). A simple schematic
diagram given at the end will help in understanding the points I
am raising.
An
arsenic risk management strategy in any given country involves
two major issues. These are development and implementation of a
mitigation strategy and the development and implementation of an
adaptation strategy. The former entails putting a strategy in
place and executing it so that arsenic toxicity no longer can
occur or can occur only marginally among the population who are
at present not at risk. An adaptation strategy, on the other
hand, is aimed at the people who have already been exposed and
affected by arsenic toxicity. Such a strategy, therefore, tries
to minimise the adverse effects of the exposure. An adaptation
strategy must have as its basic elements aspects of medical
treatment, provision for purification of water for agricultural
use and human consumption, social and economic rehabilitation of
the affected people, ensuring supply of arsenic-free food and
feed (for livestock) and very importantly a safe disposal
mechanism for the waste arsenic left after purification of
water. So far only the purification and to some extent medical
treatment issues have received attention by the authorities
concerned. Little has been discussed in relation to agricultural
use or safe disposal of the concentrated As waste.
A
common element in the development of the two types of strategy
is the rigorous and scientific understanding of the natural
processes involved in the occurrence and propagation of arsenic
both within nature and the subsequent spread through food chains
including drinking water into living organisms including human
beings and subsequent biological changes due to arsenic
toxicity. The starting point must be a critical review of
whatever is known both within the country and world-wide.
Indeed, arsenic toxicity is known to occur in various parts of
the world including the USA. Within the country, several surveys
have been conducted as indicated earlier and some are also
on-going. The results of these such as the one conducted by the
British
Geological Society may be critically reviewed as a starting
point for further scientific investigation.
Before getting into the issue of mitigation aspects of ARMS, it
should be pointed out that arsenic toxicity is a problem of
quality of ground water. Surface water in general is free of
this problem. The development of a mitigation strategy has to
look into two specific aspects. One of these relates to ensuring
water for household use.
The
issue of mitigation therefore must take into account the problem
of finding alternative sources and technologies for supply of
As-free water for both agriculture and drinking. This should
involve analyses of the reasons for and consequent implications
of substitution of surface water for ground water.
A
major reason for the spread of hand tubewells had been to
provide drinking water free of harmful pathogens. Returning to
surface water sources should therefore consider water free of
both As and such pathogens.
The
issue of agriculture and food security is extremely important.
So far we had been concentrating on the issue of drinking water.
But we yet do not know for sure how As might get into the food
chain through irrigation water. As may enter the human body both
through food and feed for animals (the products of which are
also consumed). Secondly, we do not as yet know what happens to
productivity of agriculture in general and crops in particular
if As-contaminated water is used for irrigation. If these are
adversely affected, we will have in our hand a problem both of
quantity and quality of food and feed. Food security is likely
to be threatened and costly imports may be needed. These costs
must be factored in while devising an adaptation and a
mitigation strategy
Technological innovation, their cost effectiveness and
popularisation therefore constitute core elements of an
effective arsenic risk management strategy. Particularly, the
issue of costs is extremely important. For cost effectiveness of
the measures for the development and implementation of both the
mitigation and adaptation strategies, one needs to be very clear
about all the available alternative technical options.
A
credible mitigation strategy, as the above discussion suggests,
must find out the opportunity costs of the alternatives to use
of ground water, which may form a significant part of the social
costs. These may include the costs of alternative irrigation
systems and of provision of drinking water free of harmful
pathogens and probably also the costs of alternative sources of
food for food security. Also, as a least-cost mitigation and
adaptation strategies are needed, it appears that their economic
and financial aspects probably shall have to be assessed through
the modeling of the whole system.
Time sequence of measures may also have a significant influence
on the effectiveness and costs of the strategies. These should
therefore be integrated carefully within them.
Whatever be the final ARMS, these would need effective
institutionalisation of the whole system. This is one area where
Bangladesh has always been lagging. A bureaucracy-ridden system
will not do. While in terms of planning and designing the
elements of the strategies, the institutions must depend on
solid scientific information and interpretation, in their
implementation they must be totally field-oriented. Combining
the two will of course be easier said than done. But too much
and the lives of too many are at stake for this to be treated
lightly.
The
bare elements of a comprehensive strategy for arsenic risk
management has been outlined above. These must be elaborated
more fully, discussed and debated by the stakeholders, more so
by those who are facing the menace everyday in their lives.
Thus, a totally people-centred approach will be needed for
understanding the problem on the ground and acting accordingly.
The
motto of the World Environment day, 2000 is that it is "Time to
Act". Let us wake up fully and be on a war-footing to win the
coming battles for saving millions of people of Bangladesh from
the silent killer that is stalking the land.
Prepared by
M. Asaduzzaman
Research Director
Bangladesh Institute of Development Studies & Project Director,
SDNP
Email: asad@sdnbd.org
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