Aral Catastrophe Recorded in DNA
From: Robina Suwol
Date: 06 Jul 2004
Remote Name: 188.8.131.52
Aral catastrophe recorded in DNA
By David Shukman
BBC science correspondent in Muynak, Uzbekistan
Fresh fears have been raised about the health of populations living near the
shrinking Aral Sea in central Asia.
A new study has now found high levels of DNA damage that could explain the
region's abnormally high cancer rates.
This comes as the latest estimates say the Aral Sea is receding so rapidly it
could vanish within the next 15 years.
Once the world's fourth largest inland body of water, the sea has been drained
by a poorly managed irrigation system that supplies water to cotton crops.
If ever there was an example of manmade ecological and human catastrophe, the
Aral Sea and the dusty, salt-encrusted lands around it must be the most vivid
anywhere on the planet.
In fact, it is no longer true to talk of the sea as a single entity. In the
late 1980s, its level fell so low that the centuries-old body of water divided
In the last eight years, the sea has fallen another 5m (16ft) and soon you can
expect official confirmation that the larger of its two parts has been divided
What is left when these seas retreat is a vision of environmental apocalypse:
vast stretches of desert, laden with heavy doses of salt and burdened with a
toxic mix of chemical residues washed down over the decades from the farms
Gone are the cooling breezes that once made the town of Muynak attractive.
This fishing port used to boast busy docks and the largest fish processing
plant in the Soviet Union.
Now the sea is only reached after a long day's driving over harsh terrain. The
jobs have disappeared and even the cleanest water is dangerously salty.
Dust blows everywhere and carries with it toxins that enter the food chain.
The impact on public health is devastating. Malnutrition is rife as are
conditions including anaemia and TB.
Most alarming is a rate of a particular form of cancer - cancer of the
oesophagus - that is the highest in the world.
CONSEQUENCES OF SHRINKAGE
Aral has moved 100-150km away from the original shore Fishery - 44,000 tonnes
per year - has totally collapsed 42,000 sq km of new salty desert emerged
since 1966 Diseases - cholera, typhus, gastritis, blood cancer Highest child
mortality rate in the former USSR
Up to 80% of cancer victims in the region suffer this form of cancer.
For years the likely cause has been suspected to be the intensive use of
pesticides and herbicides on the vast cotton fields to the south of the Aral
Sea. Now new research appears to provide support for that.
Dr Spencer Wells, of the National Geographic Society and formerly Oxford
University's Wellcome Trust Centre for Human Genetics, studied DNA samples
taken from the local population and found widespread genetic damage.
The study focused on the level of a marker known as 8-OHdG and showed rates of
damage 3.5 times higher than seen in samples from the US.
In the wind
In farm workers, those closest to the agricultural chemicals, the rate
increased to 5 times.
According to Dr Wells, the implications of this could be long lasting.
"This means not only that people are more likely to get cancer but also that
their children and grandchildren are too," he told BBC News Online.
The water has been taken to feed the "white gold" - cotton
What is not proven is whether the genetic mutations found in the adults are
indeed passed on to later generations. That will take further study.
In the meantime, the cancer wards in the main hospital in the provincial
capital Nukus are overburdened.
One patient is 61-year-old Saparbey Kazahbaev, a biologist who has spent the
last 30 years living beside the Aral Sea and studying the effects of its
He is now recovering from surgery to remove a tumour from his oesophagus.
Too weak to raise himself from his bed, he explained in a rasping voice how
the poisonous salts in the air have a double effect on humans.
First they enter the respiratory system; second they enter the food chain
through plants and animals that are eaten.
The government of Uzbekistan denies it has a major healthcare problem on its
The worst affected region falls in the province of Karakalpakstan and the
region's deputy health minister, Atajan Hamraev, admitted there were problems
but said they were under control.
We asked him whether it was wise to continue growing cotton, given the way it
soaks up all the water that used to flow into the Aral Sea and the new
evidence of health risks from the chemicals sprayed on the crops.
His response was defiant: cotton is Uzbekistan's biggest export earner.
Mr Hamraev said that stopping the growing of cotton would make public health
worse and leave stomachs empty. "There's no alternative," he said.
So the cotton fields are busy, the sea shrinks and the hospitals struggle to
Last changed: March 14, 2006