The 1971 Iraq poison grain disaster was caused by grain treated with methylmercury fungicide being imported and used to make bread, poisoning over 6,500 people and killing 459. Methylmercury is a toxic form of mercury that forms when bacteria react with mercury in plants, soil or water. It was used to treat grain but warnings were not understood, and the dyed grain was washed, removing the warnings but not the toxins. Symptoms included numbness, loss of balance, blindness and death from nervous system damage. Over 40,000 were poisoned, with long term effects continuing due to mercury's long half life in the brain.

1. 1971 Iraq Poison Grain Disaster and Methylmercury :
Prepared by:
Chemistry.Waqar Ahmad Khan
Email: Waqarahmadkhan1990@gmail.com

2. What Is Methylmercury ?
 is an organometallic cation with the formula [CH3Hg]+. It is
a bioaccumulative environmental toxicant.

3. Methylmercury Poisoning Causes :
 Methylmercury poisoning is brain and nervous system damage from the chemical
methylmercury.
 Methylmercury is a very poisonous form of mercury. It forms when bacteria react with
mercury in water, soil, or plants. It has been used to preserve grain that is fed to animals.
 Methylmercury poisoning has occurred in people who have eaten meat from animals that
ate grain that was treated with this from of mercury. Poisoning from eating fish from water
that is contaminated with methylmercury has also occurred .
 The FDA recommends that women who are pregnant, or may become pregnant, and
nursing mothers avoid fish that may contain unsafe levels of methylmercury.

4. Symptoms Of Methylmercury Poisoning Include :
 Blindness
 Cerebral palsy
 Deafness
 Growth Problems
 Lung Function Impairment
 Small Head

5. 1971 Iraq poison grain disaster
 The 1971 Iraq poison grain disaster was a mass methyl mercury poisoning
incident that began in late 1971. Grain treated with a
methylmercury fungicide and never intended for human consumption was
imported into Iraq as seed grain from Mexico and the United States.

6. Epidemic of Mercury Poisoning In Iraq
 The significant outbreak in Iraq took place in the winter of 1971-1972 , and the
incidence of patient increased sharply early in January 1972 . Seed grain treated
with a methylmercury fungicide was used to prepare homemade bread in rural
communities throughout the country . The primary cause of the poisoning was
traced to the ingestion of seed wheat that was used for making flour .

7. Epidemic of Mercury Poisoning In Iraq
 Also ingestion probably began in October-November 1971 , and the first patient with
severe poisoning were admitted to the hospital at thee end of December 1971 . This
incidence developed into the most catastrophic epidemic ever recorded with 6,530 people
hospitalized by March 27 of the following year , of whom 459 died in the hospital .

9. The Cause Of 1971 Iraq poison grain disaster :
 Organic Mercury has certain antifungal properties that make them beneficial when applied
to seed grain. However, people often were unaware that if these seeds were consumed
directly rather than planted, they would become very ill. In addition to warning labels,
manufacturers started coloring the grain pink as a sign of their toxicity if consumed.
Unfortunately those distributing the grain in Iraq could not read English and were unaware
of the typical "skull and crossbones" poisoning label. The dye also counterproductive
consequences. Many felt that is they washed the dye off, the toxins would be washed off as
well. All of this miscommunication had disastrous effects with more than 40,000 being
poisoned

10. Symptoms :
 The effect of mercury took some time – the latent period between ingestion and the first
symptoms (typically paresthesia – numbness in the extremities) was between 16 and 38
days. Paresthesia was the predominant symptom in less serious cases. Worse cases
included ataxia (typically loss of balance), blindness or reduced vision, and death resulting
from central nervous system failure. Anywhere between 20 and 40 mg of mercury has been
suggested as sufficient for paresthesia (between 0.5 and 0.8 mg/kg of body weight). On
average, individuals affected consumed 20 kg or so of bread; the 73,000 tonnes provided
would have been sufficient for over 3 million cases

11. Effect :
 A large number of patients with minor symptoms recovered completely; those with more serious
symptoms improved. This was in contrast to expected outcomes, largely based on analysis
of Minamata disease in Japan. In boys with mercury levels below clinical poisoning, a reduction in
school performance was noted, although this correlation could not be confirmed.
 In infants, the mercury poisoning caused central nervous system damage.
 Different treatments for mercury poisoning have been developed, and "quiet baby syndrome",
characterized by a baby who never cries, is now a recognized symptom of methylmercury-induced
brain damage.
 In 1974, a joint Food and Agriculture Organization (FAO) and World Health Organization (WHO)
meeting made several recommendations to prevent a similar outbreak. These included stressing the
importance of labelling bags in the local language and with locally understood warning symbols.
 Iraq now has the highest incidence of Parkinson's in the world. Parkinson's symptoms are very
similar to mercury poisoning symptoms. Mercury that enters the brain has a half-life of 27.5 years
and chelators are not able to remove it.

12. Treatment :
 The World Health Organization (WHO) assisted the Iraqi government through the supply
of drugs, analytical equipment and expertise. Many new treatments were tried, since
existing methods for heavy metal poisoning were not particularly effective. Dimercaprol
was administered to several patients, but caused rapid deterioration of their condition. It
was ruled out as a treatment for this sort of poisoning following the outbreak. Polythiol
resins, penicillamine and dimercaprol sulfonate all helped.
 The result of all treatments was varied, with some patients' blood mercury level being
dramatically reduced, but a negligible effect in others. All patients received periods of
treatment interspersed with lay periods; continuous treatment was suggested in future
cases.

13. Reference's :
 Clarkson, T. W. (2002). "The Three Modern Faces of Mercury". Environmental Health
Perspectives, 110 Suppl 1, 11-23.
 Gilbert, Steven G. A Small Dose of Toxicology. CRC Press, 2004.
 Skerfving SB, Copplestone JF (1976). "Poisoning caused by the consumption of
organomercury-dressed seed in Iraq". Bull. World Health Organ. 54 (1): 101–
112. PMC 2366450. PMID 1087584.