Diapositiva 1

1
CONCENTRATION AND SPATIAL VARIABILITY OF ARSENIC
IN THE WATER SUPPLY DETERMINATION OF BASIC FIELD
DATA FOR THE PREVENTION OF HYDROARSENICISM Paoloni
, Juan Darío(1), Sequeira, Mario Eduardo(2),
Fiorentino, Carmen Elida(3) , Caferri, María
Isabel(4) (1) CONICET, Bahía Blanca, Buenos
Aires, Argentina. (2) UNS-CONICET, Bahía Blanca,
Buenos Aires, Argentina. (3) UNS, Bahía Blanca,
Buenos Aires, Argentina. (4) Sociedad Argentina
de Dermatología, Bahía Blanca, Buenos Aires,
Argentina.
AIM OF THE STUDY
The presence of hazardous levels of natural
contaminants in the water supply carries serious
health implications for the com-munities
depending on such supply. The drinking water
of some two million people over an area of
1,7x106 Km2 in the southern cone of America
(Argentina and Chile) currently contains more
than 50 ?g/l of arsenic, well above the maximum
guideline value (10 ?g/l) published by the World
Health Organization (1). The population in this
area is therefore exposed to the potential
development of chronic endemic hydroarsenicism
not only through its drinking water but also
indirectly through the ingestion of food produced
from crops under irrigation from the same water
supply. Hydroarsenicism is a determinant of a
number of diseases, including skin disorders.
The aim of the present study is to provide
detailed insight into the concentration and
distribution of arsenic in water supplies and to
make the information available to those
responsible for health-related prevention and
sanitary education programs
METHODS
RESULTS
The study area was selected from
political-administrative districts of a province
of Argentina on the basis of already existing
data and considerations relating to the regional
relevance and scientific interest of the zone.
Maps of the Instituto Geográfico Militar
(Military Geographical Institute) on a scale of
150.000 and 1100.000 were used together with
Landsat satellite images. Samples were
selectively collected both from surface water and
from wells and perforations used to exploit
groundwater, the latter being the main
multi-purpose water supply. Data on the depth and
temperature of the water were also recorded.
Hydrochemical analyses using the Induced Coupled
Plasma - ICP technique to determine the arsenic
concentrations and routine determinations were
carried out in the laboratory.
The results are presented in the form of a map
showing the distribution and variability of
arsenic concentrations throughout the study area
(Figure 1). The findings will facilitate the
design of preventive programs and the provision
of therapeutic treatment to those suffering the
consequences of this carcinogenic substance in
the water supply. Wider diffusion of the field
data will help prevention of further potentially
serious consequences and serve to educate the
local population about dangers posed by
degradation in the quality of the water they
drink. The findings of the study will also be
available to pertinent public and private
organisms and institutions, in particular in
those areas where arsenic contamination is
already affecting public health.
CONCLUSIONS
The study reports the zones most affected by risk
related concentrations of arsenic in the water
supply and those free of arsenic, thus defining
an arsenic vulnerability map. The local community
in the most affected areas will evidently have a
higher propensity to develop chronic regional
endemic hydroarsenicism.
BIBLIOGRAPHY
1. Fernández Turiel, J.L., Galindo, G., Parada,
M.A., Gimeno, D., García Vallès, M., Saavedra, J.
2005. Estado actual del conocimiento sobre el
arsénico en el agua de Argentina y Chile Origen,
movilidad y tratamiento (Current state of
knowledge on arsenic in waters of Argentina and
Chile Origin, mobility and treatment).II
Seminario Hispano-Latinoamericano Sobre Temas
Actuales de Hidrología Subterránea. IV Congreso
Hidrogeológico Argentino. (II Hispanic-Latin
American Seminar on Current Themes in Groundwater
Hydrology. IV Argentinean Hydrology Congress)
Río Cuarto, Argentina).