Iran is unique in the world today
it has tens of thousands of victims
of chemical weapons weapons use
during the iran-iraq war in the 1980s
sulfur mustard, nerve agents for the first time
were used on the battlefield in that war
it's been more than thirty years since these victims
were exposed to the chemicals and now
scientists are unraveling the long-term effects
and also looking at the
basic mechanisms of chemical weapons
and how they affect the body initially the acute
effects and then in the long term
as these consequences happen many years later
I am Richard stone international news editor for science
I went to Iran to report on survivors of
chemical weapons attacks in a project sponsored
by the Pulitzer Center for Crisis Reporting
The first large-scale use of chemical weapons
was during World War one
That was mostly mustard and chlorine
And it was many years after that
that chemical weapons were used on a large scale in
the battlefield and that took place
during the Iran-Iraq war
Sulfur mustard is very corrosive chemical
it's not like the nerve agents
it's been around for more than a century
it was used in WWI but its mechanism of action is still
rather opaque it blisters so
if you get on the skin it forms these huge blisters
called bullae, if you breathe it in
it attacks the lung cells and if you get
into your eyes it can also cause quite big damage there
as an oily substance
it is absorbed quite easily
so if you survive sulfur mustard it
takes a while for you to heal
the blisters take months to heal
Many years later people are discovering that
the lung damage that was caused by
the acute exposure
it sets a molecular mechanism in motion
like a little time bomb that explodes later
into very life-threatening symptoms
the lung tissue breaking down,
you become more prone to lung infections
and a lot of people succumb
months or years later after the exposure
to these effects and the mechanism
molecular mechanism of these effects is
still being worked out
so Iran has a huge population of mustard victims who
are still suffering symptoms
tens of thousands of people
it's a unique cohort
to try to develop better strategies
to treat mustard and also if there's some way to
develop chemicals, compounds
that can be applied during the initial attack
right now that antidote to sulfur mustard does not exist
all nerve agents attack an enzyme
called acetylcholinesterase
it's vital to the body
it breaks down the neurotransmitter acetylcholine
so it is essential for maintaining levels of
the neurotransmitter in the synapses
one of the most insidious effects of nerve agents
is that after they bind to acetylcholinesterase
this bond over time hardens,
becomes permanent essentially
and this is called aging
so as acetylcholine builds up in the synapses
it over stimulates the nerves cells
and that has a variety of effects so it
can lead to seizures, convulsions
when the nerve agent enters the brain and
starts interacting with the enzyme there
it sends victims into a coma and unless
they're treated really quickly
they will usually stop breathing
so soldiers who are exposed
to nerve agents carry three countermeasures
that they can self-inject or inject into a buddy
one is called atropine,
it binds to the same enzyme that the nerve agents
bind to, therefore preventing the nerve agent
from exerting its effects
another is an oxime that
if a nerve agent is attached to the enzyme
it pries it off, so it's like a little molecular crowbar
and the third is an anticonvulsant
one of the major symptoms of nerve agent exposure is
seizures and this anticonvulsant takes care of that.
for a long time people thought that if you're
exposed to a nerve agent,
you either lived or died
if you survived the nerve agent attack
you went on to live a normal, average, healthy life,
it didn't have long-term effects people presumed
that began to change especially,
after the Tokyo terror attacks
it was clearly documented that people
exposed to sarin did suffer long-term consequences.
That's a new revelation and
Iranian scientists see an opportunity
now to try to track down
victims of the nerve agent attacks
and monitor their current health and
see if they can contribute to the developing picture
of the long-term effects of nerve agents
so this is a unique resource for scientists
it's a very tragic story for the victims
but to be able to study using modern tools,
the effects of chemical weapons on the human body
this is the only place right now
where scientists can do that