| WHAT HUMAN HAIR CAN TELL ABOUT ENVIRONMENTAL POLLUTION AT THE ARAL SEA
Carole Dauberschmidt, Michel Yegles, Robert Wennig
Laboratoire National de Santé, Division Toxicologie, Centre Universitaire,
L-1511 Luxembourg
The environment of the Aral Sea region has changed dramatically during the last
40 years. Shortsighted irrigation practices let the Aral Sea surface shrink to
one half of the original surface, causing a 90 % decrement of air humidity and
an increment of salty dust in the air by windblown sediments. Moreover, the
remains of water reaching the Aral Sea were contaminated with fertilizers and
pesticides used in the intensively cultivated fields. At the same time, the
state of health of people living in the affected regions deteriorated
considerably. Many children showed an impairment of respiratory, renal,
digestive, and blood systems. At the National laboratory of health in
Luxembourg, trace elements in hair specimens originating from the Aral Sea
region of Kazakhstan (n = 6) were measured by X-ray fluorescence spectrometry.
Concentrations of the element Cl were up to 4 times higher compared to values
found in European hair. Analyses of Kazakh drinking water samples (n = 12)
revealed that concentrations of chloride and sodium, as well as the number of
bacteria in specimens from the Aral sea region were far above maximal permitted
levels in Europe. This indicated that surface water was highly contaminated with
salt originating very likely from the former Aral Sea ground. The high sodium
concentration and high number of bacteria in drinking water could be at least
partly responsible for the impaired state of health of the local Kazakh
population. In addition, chloride could theoretically be sequestered into hair,
when consumed daily due to high concentrations in drinking water. These findings
were supported by the fact that children living in Almaty, were asymtomatic. The
former Kazakh Capital is situated more than 700 km east of Aral Sea region and
is supplied with clean fresh water from the near-by mountain range.
Another hypothesis to explain the high levels of the element Cl in Kazakh
hair samples could be the high organochlorine (PCBs, DDT, lindane) body burdens.
A Swedish team had measured levels of organochlorines in blood of Kazakh
children (n = 12) being 1 to 2 orders above Western Europe reference values. To
check this hypothesis, a method for analyzing organochlorine compounds in hair
had to be developed. Preliminary results indicate that there are no significant
differences between organochlorine concentrations found in Kazakh (n = 2) and in
European (n = 3) hair analyzed so far. Measured concentrations of lindane, DDT,
PCB Nos. 138, 153, and 180 were between 0.5 to 5 pg/mg hair. Further studies are
scheduled in order to elucidate if and to which extent relations between blood
and hair organochlorine concentrations can be found.
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