Basra poison grain disaster
Encyclopedia
The 1971 Iraq poison grain disaster was a mass methylmercury
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
. Due to a number of factors, including foreign-language labelling and late distribution within the growing cycle, this toxic grain was consumed as food by Iraqi residents in rural areas. People suffered from parathesia (numbness of skin), ataxia
(lack of coordination of muscle movements) and loss of vision, symptoms similar to those seen when Minamata disease
affected Japan
. The recorded death toll was 650 people, but figures at least ten times greater have been suggested. The 1971 poisoning was the largest mercury poisoning disaster when it occurred, with cases peaking in January and February 1972 and stopping by the end of March.
Reports after the disaster recommended tighter regulation, better labelling and handling of mercury-treated grain, and wider involvement of the World Health Organization
in monitoring and preventing poisoning incidents. Investigation confirmed the particular danger posed to fetuses and young children.
. However, in Europe and America, its health risks (even when consumed in small quantities) were known. Methylmercury had been banned in Sweden in 1966, the first country to do so, and the United Kingdom
followed in 1971. Previous mercury-poisoning incidents had occurred in Iraq in 1956 and 1960. In 1956, there had been around 200 cases, and 70 deaths; in 1960 there had been 1000 cases and 200 deaths, in both cases due to ethylmercury
compounds. Among the recommendations made after the 1960 incident had been to color any toxic grain, for easy identification. Before the 1971 incident, around 200–300 cases of methylmercury poisoning had been reported worldwide. Drought had reduced harvests in 1969, when it had affected 500,000 people, and 1970. Saddam Hussein
's government decided to import mercury-coated grain to act as seed. Hussein himself may have formerly worked in the Department of Agriculture, in the aftermath of the 1960 incident.
grain and 22,262 tonnes of barley
), colored in a pink-orange hue, were shipped to Iraq from the United States
and Mexico
. The wheat arrived in Basra
on SS Trade Carrier between 16 September and 15 October, barley between 22 October and 24 November 1971. Iraq's government chose Mexipak, a high-yield wheat seed developed in Mexico by Norman Borlaug
. The seeds contained an average of 7.9 μg/g of mercury, up to nearly twice that. The decision to coat it in mercury has been reported as made by the Iraqi government, rather than the grain supplier, Cargill
. The three Northern governorates of Ninawa
, Kirkuk, and Erbil together received more than half the shipments. Contributing factors to the epidemic included the fact that distribution had started late, and much grain had arrived after the October–November planting season.
Farmers holding grain ingested it instead, since their own planting had been completed. Distribution was hurried, and open, with grain being distributed free of charge in cases, or with payment in kind. Some farmers sold their own grain, lest this new grain devalue what they had. This left them dependent on tainted grain for the winter. Many Iraqis were either unaware of the significant health risk posed, or chose to ignore the warnings. Initially, farmers were to certify – with a thumbprint or signature – that they understood the grain was poison. According to some sources, distributors did not ask for such an indication. Warnings on the sacks were in Spanish and English, not at all understood, or included the black-and-white skull and crossbones design, which meant nothing to Iraqis. The long latent period may have granted farmers a false sense of security, when animals fed the grain appeared to be fine. The red dye washed off the grain; the mercury did not. Hence, washing may have given only the appearance of removing the poison. Mercury was ingested through the consumption of homemade bread, meat and other animal products obtained from livestock given treated barley, vegetation grown from soil contaminated with mercury, game birds that had fed on the grain and fish caught in rivers, canals, and lakes into which treated grain had been dumped by the farmers. Ground seed dust inhalation was a contributing factor in farmers during sowing and grinding. Consumption of ground-flour through homemade bread is thought to have been the major cause, since no cases were reported in urban areas, where government flour supplies were commercially regulated.
– 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 20–40 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.
The hospital in Kirkuk
received large numbers of patients with symptoms that doctors recognised from the 1960 outbreak. The first case of alkylmercury poisoning was admitted to hospital on 21 December. By 26 December, it had issued a specific warning to the government. By January 1972, the government had started to strongly warn the populace about eating the grain, although dispatches did not mention the large numbers already ill. The Iraqi Army
soon ordered disposal of the grain, and eventually declared death penalty for anyone found selling it. Farmers dumped their supplies wherever possible, and it soon got into the water supply (particularly the River Tigris), causing further problems. The government issued a news blackout, and released little information about the outbreak.
The World Health Organization
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, which caused the 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, but this is believed to be largely insignificant in overall recovery and outcomes. Dialysis
was tested on a few patients late on in the treatment period, but they showed no clinical improvement. The result of all treatments was varied, with some patients' blood mercury level dramatically reducing, others with a negligible effect. All patients received periods of treatment interspersed with lay periods; continuous treatment was suggested in future cases. Later treatment was less effective in reducing blood toxicity.
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, it also caused central nervous system
damage. Lower doses caused slower development in children, and abnormal reflexes. Different treatments for mercury poisoning have since been developed, and "quiet baby syndrome", characterised by a baby who never cries, is now a recognised symptom of methylmercury-induced brain damage. Ongoing recommendations of the food regulation authorities have focused on consumption by pregnant women and infant children, noting the particular susceptibility of fetuses and infants to methylmercury poisoning. Data from Iraq has confirmed that methylmercury can pass to a child in utero
, noting also that mercury levels were equal to or higher in the newborn child than in the mother.
In 1974, a joint Food and Agriculture Organization
(FAO) and World Health Organisation (WHO) meeting was held, making several recommendations to prevent a similar outbreak. This included stressing the importance of labelling bags in the local language, and with locally understood warning signs. The possibility of an additive creating a strong bitter taste was studied. The meeting urged governments to strictly regulate methyl- and ethylmercury use in their respective countries, including limiting use to where no other reasonable alternative was available. It also recommended the involvement of the FAO and WHO in assisting national governments in regulation and enforcement, and the setting up of national poison control centers. Over 9–13 November, a Conference on Intoxication due to Alkylmercury-Treated Seed was held in Baghdad
, Iraq. It supported the recommendations of the FAO/WHO report. It further suggested local and national media should publicise outbreaks, including size and symptoms; it considered the distribution of this information crucial. It also laid out a general plan as to the collection of relevant information from the field, and potential analysis for further investigation. It called on national governments to make use of WHO involvement whenever plausible, and absolved world governments in clear terms, saying that "No country should ever feel that any blame will attach to it for allowing an outbreak to occur".
Methylmercury
Methylmercury is an organometallic cation with the formula . It is a bioaccumulative environmental toxicant.-Structure:...
poisoning incident that began in late 1971. Grain treated with a methylmercury fungicide
Fungicide
Fungicides are chemical compounds or biological organisms used to kill or inhibit fungi or fungal spores. Fungi can cause serious damage in agriculture, resulting in critical losses of yield, quality and profit. Fungicides are used both in agriculture and to fight fungal infections in animals...
and never intended for human consumption was imported into Iraq
Iraq
Iraq ; officially the Republic of Iraq is a country in Western Asia spanning most of the northwestern end of the Zagros mountain range, the eastern part of the Syrian Desert and the northern part of the Arabian Desert....
as seed grain from Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
and the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. Due to a number of factors, including foreign-language labelling and late distribution within the growing cycle, this toxic grain was consumed as food by Iraqi residents in rural areas. People suffered from parathesia (numbness of skin), ataxia
Ataxia
Ataxia is a neurological sign and symptom that consists of gross lack of coordination of muscle movements. Ataxia is a non-specific clinical manifestation implying dysfunction of the parts of the nervous system that coordinate movement, such as the cerebellum...
(lack of coordination of muscle movements) and loss of vision, symptoms similar to those seen when Minamata disease
Minamata disease
', sometimes referred to as , is a neurological syndrome caused by severe mercury poisoning. Symptoms include ataxia, numbness in the hands and feet, general muscle weakness, narrowing of the field of vision and damage to hearing and speech. In extreme cases, insanity, paralysis, coma, and death...
affected Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
. The recorded death toll was 650 people, but figures at least ten times greater have been suggested. The 1971 poisoning was the largest mercury poisoning disaster when it occurred, with cases peaking in January and February 1972 and stopping by the end of March.
Reports after the disaster recommended tighter regulation, better labelling and handling of mercury-treated grain, and wider involvement of the World Health Organization
World Health Organization
The World Health Organization is a specialized agency of the United Nations that acts as a coordinating authority on international public health. Established on 7 April 1948, with headquarters in Geneva, Switzerland, the agency inherited the mandate and resources of its predecessor, the Health...
in monitoring and preventing poisoning incidents. Investigation confirmed the particular danger posed to fetuses and young children.
Context
The properties of mercury make it a successful fungicideFungicide
Fungicides are chemical compounds or biological organisms used to kill or inhibit fungi or fungal spores. Fungi can cause serious damage in agriculture, resulting in critical losses of yield, quality and profit. Fungicides are used both in agriculture and to fight fungal infections in animals...
. However, in Europe and America, its health risks (even when consumed in small quantities) were known. Methylmercury had been banned in Sweden in 1966, the first country to do so, and the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
followed in 1971. Previous mercury-poisoning incidents had occurred in Iraq in 1956 and 1960. In 1956, there had been around 200 cases, and 70 deaths; in 1960 there had been 1000 cases and 200 deaths, in both cases due to ethylmercury
Ethylmercury
Ethylmercury is a cation composed of an ethyl group bound to a mercury centre; its chemical formula is C2H5Hg+...
compounds. Among the recommendations made after the 1960 incident had been to color any toxic grain, for easy identification. Before the 1971 incident, around 200–300 cases of methylmercury poisoning had been reported worldwide. Drought had reduced harvests in 1969, when it had affected 500,000 people, and 1970. Saddam Hussein
Saddam Hussein
Saddam Hussein Abd al-Majid al-Tikriti was the fifth President of Iraq, serving in this capacity from 16 July 1979 until 9 April 2003...
's government decided to import mercury-coated grain to act as seed. Hussein himself may have formerly worked in the Department of Agriculture, in the aftermath of the 1960 incident.
Causes
Some 95000 tonnes (93,499.3 LT) of grain (73,201 tonnes of wheatWheat
Wheat is a cereal grain, originally from the Levant region of the Near East, but now cultivated worldwide. In 2007 world production of wheat was 607 million tons, making it the third most-produced cereal after maize and rice...
grain and 22,262 tonnes of barley
Barley
Barley is a major cereal grain, a member of the grass family. It serves as a major animal fodder, as a base malt for beer and certain distilled beverages, and as a component of various health foods...
), colored in a pink-orange hue, were shipped to Iraq from the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
and Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
. The wheat arrived in Basra
Basra
Basra is the capital of Basra Governorate, in southern Iraq near Kuwait and Iran. It had an estimated population of two million as of 2009...
on SS Trade Carrier between 16 September and 15 October, barley between 22 October and 24 November 1971. Iraq's government chose Mexipak, a high-yield wheat seed developed in Mexico by Norman Borlaug
Norman Borlaug
Norman Ernest Borlaug was an American agronomist, humanitarian, and Nobel laureate who has been called "the father of the Green Revolution". Borlaug was one of only six people to have won the Nobel Peace Prize, the Presidential Medal of Freedom and the Congressional Gold Medal...
. The seeds contained an average of 7.9 μg/g of mercury, up to nearly twice that. The decision to coat it in mercury has been reported as made by the Iraqi government, rather than the grain supplier, Cargill
Cargill
Cargill, Incorporated is a privately held, multinational corporation based in Minnetonka, Minnesota. Founded in 1865, it is now the largest privately held corporation in the United States in terms of revenue. If it were a public company, it would rank, as of 2011, number 13 on the Fortune 500,...
. The three Northern governorates of Ninawa
Ninawa Governorate
Ninawa is a governorate in northern Iraq, and the Arabic name for the biblical city of Nineveh in Assyria. It has an area of and an estimated population of 2,453,000 people in 2003. Its chief city and provincial capital is Mosul, which lies across the Tigris river from the ruins of ancient...
, Kirkuk, and Erbil together received more than half the shipments. Contributing factors to the epidemic included the fact that distribution had started late, and much grain had arrived after the October–November planting season.
Farmers holding grain ingested it instead, since their own planting had been completed. Distribution was hurried, and open, with grain being distributed free of charge in cases, or with payment in kind. Some farmers sold their own grain, lest this new grain devalue what they had. This left them dependent on tainted grain for the winter. Many Iraqis were either unaware of the significant health risk posed, or chose to ignore the warnings. Initially, farmers were to certify – with a thumbprint or signature – that they understood the grain was poison. According to some sources, distributors did not ask for such an indication. Warnings on the sacks were in Spanish and English, not at all understood, or included the black-and-white skull and crossbones design, which meant nothing to Iraqis. The long latent period may have granted farmers a false sense of security, when animals fed the grain appeared to be fine. The red dye washed off the grain; the mercury did not. Hence, washing may have given only the appearance of removing the poison. Mercury was ingested through the consumption of homemade bread, meat and other animal products obtained from livestock given treated barley, vegetation grown from soil contaminated with mercury, game birds that had fed on the grain and fish caught in rivers, canals, and lakes into which treated grain had been dumped by the farmers. Ground seed dust inhalation was a contributing factor in farmers during sowing and grinding. Consumption of ground-flour through homemade bread is thought to have been the major cause, since no cases were reported in urban areas, where government flour supplies were commercially regulated.
Symptoms, outbreak and treatment
The effect of mercury took some time – the latent period between ingestion and the first symptoms (typically paresthesiaParesthesia
Paresthesia , spelled "paraesthesia" in British English, is a sensation of tingling, burning, pricking, or numbness of a person's skin with no apparent long-term physical effect. It is more generally known as the feeling of "pins and needles" or of a limb "falling asleep"...
– numbness in the extremities) was between 16 and 38 days. Paresthesia was the predominant symptom in less serious cases. Worse cases included ataxia
Ataxia
Ataxia is a neurological sign and symptom that consists of gross lack of coordination of muscle movements. Ataxia is a non-specific clinical manifestation implying dysfunction of the parts of the nervous system that coordinate movement, such as the cerebellum...
(typically loss of balance), blindness or reduced vision, and death resulting from central nervous system
Central nervous system
The central nervous system is the part of the nervous system that integrates the information that it receives from, and coordinates the activity of, all parts of the bodies of bilaterian animals—that is, all multicellular animals except sponges and radially symmetric animals such as jellyfish...
failure. Anywhere between 20–40 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.
The hospital in Kirkuk
Kirkuk
Kirkuk is a city in Iraq and the capital of Kirkuk Governorate.It is located in the Iraqi governorate of Kirkuk, north of the capital, Baghdad...
received large numbers of patients with symptoms that doctors recognised from the 1960 outbreak. The first case of alkylmercury poisoning was admitted to hospital on 21 December. By 26 December, it had issued a specific warning to the government. By January 1972, the government had started to strongly warn the populace about eating the grain, although dispatches did not mention the large numbers already ill. The Iraqi Army
Iraqi Army
The Iraqi Army is the land component of the Iraqi military, active in various forms since being formed by the British during their mandate over the country after World War I....
soon ordered disposal of the grain, and eventually declared death penalty for anyone found selling it. Farmers dumped their supplies wherever possible, and it soon got into the water supply (particularly the River Tigris), causing further problems. The government issued a news blackout, and released little information about the outbreak.
The World Health Organization
World Health Organization
The World Health Organization is a specialized agency of the United Nations that acts as a coordinating authority on international public health. Established on 7 April 1948, with headquarters in Geneva, Switzerland, the agency inherited the mandate and resources of its predecessor, the Health...
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
Heavy Metal Poisoning
Heavy Metal Poisoning is a song by American rock band Styx. It was included as the fifth track on their 1983 studio album Kilroy Was Here.The song in the story of Kilroy Was Here has the character of Dr Righteous preaching the evils of rock and roll...
were not particularly effective. Dimercaprol
Dimercaprol
Dimercaprol or British anti-Lewisite , is a compound developed by British biochemists at Oxford University during World War II. It was developed secretly as an antidote for lewisite, the now-obsolete arsenic-based chemical warfare agent. Today, it is used medically in treatment of arsenic,...
was administered to several patients, which caused the rapid deterioration of their condition. It was ruled out as a treatment for this sort of poisoning following the outbreak. Polythiol resins, penicillamine
Penicillamine
Penicillamine is a pharmaceutical of the chelator class. It is sold under the trade names of Cuprimine and Depen. The pharmaceutical form is D-penicillamine, as L-penicillamine is toxic...
and dimercaprol sulfonate all helped, but this is believed to be largely insignificant in overall recovery and outcomes. Dialysis
Dialysis
In medicine, dialysis is a process for removing waste and excess water from the blood, and is primarily used to provide an artificial replacement for lost kidney function in people with renal failure...
was tested on a few patients late on in the treatment period, but they showed no clinical improvement. The result of all treatments was varied, with some patients' blood mercury level dramatically reducing, others with a negligible effect. All patients received periods of treatment interspersed with lay periods; continuous treatment was suggested in future cases. Later treatment was less effective in reducing blood toxicity.
Effects
6,530 patients were admitted to hospital with poisoning, and 459 deaths reported. Cases reached a peak of hundreds per day in January, and had largely subsided by the beginning of March. The last admittance was on 27 March; admissions represented every age and gender stratum, although those under the age of ten represented a third of admitted cases. This number is "certainly an underestimate", because of the availability of hospital treatment, hospital overcrowding and lack of faith in treatment. In the most severely affected areas, prevalence was 28% and mortality was 21% of the cases. Some Iraqi doctors believe both the number of cases and fatalities are at least ten times too low, with perhaps 100,000 cases of brain damage. One suggested reason for the vast difference lies in the Iraqi custom, common to large parts of the Middle East, that a person should prefer to die at home. Their deaths were therefore not recorded.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
Minamata disease
', sometimes referred to as , is a neurological syndrome caused by severe mercury poisoning. Symptoms include ataxia, numbness in the hands and feet, general muscle weakness, narrowing of the field of vision and damage to hearing and speech. In extreme cases, insanity, paralysis, coma, and death...
, in Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
. In boys with mercury levels below clinical poisoning, a reduction in school performance was noted, although this correlation could not be confirmed. In infants, it also caused central nervous system
Central nervous system
The central nervous system is the part of the nervous system that integrates the information that it receives from, and coordinates the activity of, all parts of the bodies of bilaterian animals—that is, all multicellular animals except sponges and radially symmetric animals such as jellyfish...
damage. Lower doses caused slower development in children, and abnormal reflexes. Different treatments for mercury poisoning have since been developed, and "quiet baby syndrome", characterised by a baby who never cries, is now a recognised symptom of methylmercury-induced brain damage. Ongoing recommendations of the food regulation authorities have focused on consumption by pregnant women and infant children, noting the particular susceptibility of fetuses and infants to methylmercury poisoning. Data from Iraq has confirmed that methylmercury can pass to a child in utero
In utero
In utero is a Latin term literally meaning "in the womb". In biology, the phrase describes the state of an embryo or fetus. In legal contexts, the phrase is used to refer to unborn children. Under common law, unborn children are still considered to exist for property transfer purposes.-See also:*...
, noting also that mercury levels were equal to or higher in the newborn child than in the mother.
In 1974, a joint Food and Agriculture Organization
Food and Agriculture Organization
The Food and Agriculture Organization of the United Nations is a specialised agency of the United Nations that leads international efforts to defeat hunger. Serving both developed and developing countries, FAO acts as a neutral forum where all nations meet as equals to negotiate agreements and...
(FAO) and World Health Organisation (WHO) meeting was held, making several recommendations to prevent a similar outbreak. This included stressing the importance of labelling bags in the local language, and with locally understood warning signs. The possibility of an additive creating a strong bitter taste was studied. The meeting urged governments to strictly regulate methyl- and ethylmercury use in their respective countries, including limiting use to where no other reasonable alternative was available. It also recommended the involvement of the FAO and WHO in assisting national governments in regulation and enforcement, and the setting up of national poison control centers. Over 9–13 November, a Conference on Intoxication due to Alkylmercury-Treated Seed was held in Baghdad
Baghdad
Baghdad is the capital of Iraq, as well as the coterminous Baghdad Governorate. The population of Baghdad in 2011 is approximately 7,216,040...
, Iraq. It supported the recommendations of the FAO/WHO report. It further suggested local and national media should publicise outbreaks, including size and symptoms; it considered the distribution of this information crucial. It also laid out a general plan as to the collection of relevant information from the field, and potential analysis for further investigation. It called on national governments to make use of WHO involvement whenever plausible, and absolved world governments in clear terms, saying that "No country should ever feel that any blame will attach to it for allowing an outbreak to occur".