Effects of nuclear explosions on human health
Encyclopedia
The medical effects of a nuclear blast upon humans can be put into four categories:
Some scientists estimate that a nuclear war that resulted in 110 Hiroshima-size atomic explosions would cause significant loss of life, in the tens of millions. There would also be much soot thrown up into the atmosphere which would blanket the earth, causing the disruption of food chains.
The main causes of death and disablement in this state are thermal burns and the failure of structures resulting from the blast effect. Injury from the pressure wave is minimal in contrast because the human body can survive up to 2 bar (30 psi) while most buildings can only withstand a 0.8 bar (12 psi) blast. Therefore, the fate of humans is closely related to the survival of the buildings around them.
In a nuclear explosion the human body can be irradiated by at least three processes. The first (the major cause of burns) is not caused by ionizing radiation.
In the picture on the right, the normal clothing that the woman was wearing would have been unable to attenuate the gamma radiation and it is likely that any such effect was evenly applied to her entire body. Beta burns would be likely all over the body due to contact with fallout, but thermal burns are often on one side of the body as heat radiation does not penetrate the human body. In addition, the pattern on her clothing has been burnt into the skin. This is because white fabric reflects more infra-red light than dark fabric. As a result, the skin underneath dark fabric is burned more than the skin covered by white clothing.
There is also the risk of internal radiation poisoning by ingestion of fallout particles.
. The term is generally used to refer to acute problems caused by a large dosage of radiation
in a short period, though this also has occurred with long term exposure to low level radiation. Many of the symptoms of radiation poisoning occur as ionizing radiation interferes with cell division. There are numerous lethal radiation syndromes including prodromal syndrome, bone marrow
death, central nervous system
death and gastrointestinal death.
or less is not lethal, but causes gastrointestinal distress such as anorexia
, nausea, fatigue and possibly diarrhea
.
death is caused by a dose of radiation between 2 and 10 gray and is characterized by the part of the bone marrow that makes the blood being broken down. Therefore production of red
and white blood cells and platelets is stopped by division of precursor
stem cells ceasing (4.5 gray kills 95% of stem cells). The loss of platelet
s greatly increases the chance of fatal hemorrhage. While the lack of white blood cells causes septicemia infections, the fall in red blood cells is minimal and only causes mild anemia
.
The exposure to 4.5 gray of penetrating gamma rays has many effects that occur at different times:
In 24 hours:
These will usually abate after 6–7 days.
Within 3–4 weeks there is a period of extreme illness.
The peak incidence of acute BM death corresponds to the 30 day nadir in blood cell numbers. The number of deaths then falls progressively until it reaches 0 at 60 days after irradiation. The amount of radiation greatly affects the probability of death. For example over the range of 2 to 6 gray the probability of death in untreated adults goes from about 1% to 99%, but these figures are for healthy adults. Therefore results may differ because of the thermal and mechanical injuries and infectious conditions.
and this combined with the bone marrow damage is fatal. All symptoms become increasingly severe causing exhaustion and emaciation
in a few days and death within 7–14 days from loss of water and electrolytes.
The symptoms of gastrointestinal death are:
death is the main cause of death in 24–48 hours among those exposed to 50 gray.
The symptoms are:
is susceptible to beta-emitting radioactive fallout. The principal site of damage is the germinal layer, and often the initial response is erythema
(reddening) due to blood vessel
s congestion and edema
. Erythema lasting more than 10 days occurs in 50% of people exposed to 5-6 gray.
Other effects with exposure include:
s are the most radiosensitive organ, and radiation pneumonitis can occur leading to pulmonary insufficiency and death (100% after exposure to 50 gray of radiation), in a few months.
Radiation pneumonitis
is characterized by:
for periods up to 3 years; a dose of 4 gray will cause permanent sterility.
induction is the most significant long term risk of exposure to a nuclear bomb. Approximately 1 out of every 80 people exposed to 1 gray will die from cancer and 1 in 40 people will get cancer. Different types of cancer take different times for them to appear:
, per 1,000 births and 0-20 cases of severe mental sub normality. 0.05 gray will increase death due to cancer 10 times, to 5 per 1,000. An antenatal dose of 1 gray in the first trimester causes the risk of fatal cancer to increase to 100%.
s caused by contaminated water, untreated sewage
, crowded living conditions, poor standard of living, and lack of vaccine
s in the aftermath. These diseases include:
- Initial stage -- the first 1–9 weeks, in which are the greatest number of deaths, with 90% due to thermalThermalA thermal column is a column of rising air in the lower altitudes of the Earth's atmosphere. Thermals are created by the uneven heating of the Earth's surface from solar radiation, and are an example of convection. The sun warms the ground, which in turn warms the air directly above it...
injury and/or blast effects and 10% due to super-lethal radiationRadiationIn physics, radiation is a process in which energetic particles or energetic waves travel through a medium or space. There are two distinct types of radiation; ionizing and non-ionizing...
exposure - Intermediate stage -- from 10–12 weeks. The deaths in this period are from ionization radiation in the median lethal range
- Late period -- lasting from 13–20 weeks. This period has some improvement in survivors' condition.
- Delayed period -- from 20+ weeks. Characterized by “numerous complications, mostly related to healing of thermal and mechanical injuries coupled with infertility, sub-fertility and blood disorders caused by radiation.” Also, ionizing radiation from fallout can cause genetic effects, birth defects, cancer, cataracts and other effects in organs and tissue.
Some scientists estimate that a nuclear war that resulted in 110 Hiroshima-size atomic explosions would cause significant loss of life, in the tens of millions. There would also be much soot thrown up into the atmosphere which would blanket the earth, causing the disruption of food chains.
Immediate post-attack period
Fate within certain peak overpressure
- over 0.8 bar (12 psi) - 98% dead 2% injured
- 0.3-0.8 bar (5-12 psi) - 50% dead 40% injured 10% safe
- 0.14-0.3 bar (2-5 psi) - 5% dead 45% injured 50% safe
Types of radioactive exposure after a nuclear attack
In a nuclear explosion the human body can be irradiated by at least three processes. The first (the major cause of burns) is not caused by ionizing radiation.
- Thermal burnBurnA burn is an injury to flesh caused by heat, electricity, chemicals, light, radiation, or friction.Burn may also refer to:*Combustion*Burn , type of watercourses so named in Scotland and north-eastern England...
s from infraredInfraredInfrared light is electromagnetic radiation with a wavelength longer than that of visible light, measured from the nominal edge of visible red light at 0.74 micrometres , and extending conventionally to 300 µm...
heat radiation. - Beta burns from shallow ionizing beta radiationBeta particleBeta particles are high-energy, high-speed electrons or positrons emitted by certain types of radioactive nuclei such as potassium-40. The beta particles emitted are a form of ionizing radiation also known as beta rays. The production of beta particles is termed beta decay...
(this would be from falloutNuclear falloutFallout is the residual radioactive material propelled into the upper atmosphere following a nuclear blast, so called because it "falls out" of the sky after the explosion and shock wave have passed. It commonly refers to the radioactive dust and ash created when a nuclear weapon explodes...
particles; the largest particles in local fallout would be likely to have very high radioactivity because they would be deposited so soon after detonation; it is likely that one such particle upon the skin would be able to cause a localized burn). However, these decay particles are very weakly penetrating and have a short range. - Gamma burnsRadiation burnA radiation burn is damage to the skin or other biological tissue caused by exposure to radio frequency energy or ionizing radiation.The most common type of radiation burn is a sunburn caused by UV radiation. High exposure to X-rays during diagnostic medical imaging or radiotherapy can also result...
from highly penetrating gamma radiationGamma rayGamma radiation, also known as gamma rays or hyphenated as gamma-rays and denoted as γ, is electromagnetic radiation of high frequency . Gamma rays are usually naturally produced on Earth by decay of high energy states in atomic nuclei...
. This would likely cause deep gamma penetration within the body, which would result in uniform whole body irradiation rather than only a surface burn. In cases of whole body gamma irradiation (circa 10 Gy) due to accidents involving medical product irradiators, some of the human subjects have developed injuries to their skin between the time of irradiation and death.
- See also Nuclear FalloutNuclear falloutFallout is the residual radioactive material propelled into the upper atmosphere following a nuclear blast, so called because it "falls out" of the sky after the explosion and shock wave have passed. It commonly refers to the radioactive dust and ash created when a nuclear weapon explodes...
In the picture on the right, the normal clothing that the woman was wearing would have been unable to attenuate the gamma radiation and it is likely that any such effect was evenly applied to her entire body. Beta burns would be likely all over the body due to contact with fallout, but thermal burns are often on one side of the body as heat radiation does not penetrate the human body. In addition, the pattern on her clothing has been burnt into the skin. This is because white fabric reflects more infra-red light than dark fabric. As a result, the skin underneath dark fabric is burned more than the skin covered by white clothing.
There is also the risk of internal radiation poisoning by ingestion of fallout particles.
Radiation poisoning
Radiation poisoning, also called "radiation sickness" or a "creeping dose", is a form of damage to organ tissue due to excessive exposure to ionizing radiationIonizing radiation
Ionizing radiation is radiation composed of particles that individually have sufficient energy to remove an electron from an atom or molecule. This ionization produces free radicals, which are atoms or molecules containing unpaired electrons...
. The term is generally used to refer to acute problems caused by a large dosage of radiation
Radiation
In physics, radiation is a process in which energetic particles or energetic waves travel through a medium or space. There are two distinct types of radiation; ionizing and non-ionizing...
in a short period, though this also has occurred with long term exposure to low level radiation. Many of the symptoms of radiation poisoning occur as ionizing radiation interferes with cell division. There are numerous lethal radiation syndromes including prodromal syndrome, bone marrow
Bone marrow
Bone marrow is the flexible tissue found in the interior of bones. In humans, bone marrow in large bones produces new blood cells. On average, bone marrow constitutes 4% of the total body mass of humans; in adults weighing 65 kg , bone marrow accounts for approximately 2.6 kg...
death, 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...
death and gastrointestinal death.
Prodromal syndrome
In prodromal (initial) syndrome, a dose of 1.5 grayGray (unit)
The gray is the SI unit of absorbed radiation dose of ionizing radiation , and is defined as the absorption of one joule of ionizing radiation by one kilogram of matter ....
or less is not lethal, but causes gastrointestinal distress such as anorexia
Anorexia (symptom)
Anorexia is the decreased sensation of appetite...
, nausea, fatigue and possibly diarrhea
Diarrhea
Diarrhea , also spelled diarrhoea, is the condition of having three or more loose or liquid bowel movements per day. It is a common cause of death in developing countries and the second most common cause of infant deaths worldwide. The loss of fluids through diarrhea can cause dehydration and...
.
Bone marrow death
Bone marrowBone marrow
Bone marrow is the flexible tissue found in the interior of bones. In humans, bone marrow in large bones produces new blood cells. On average, bone marrow constitutes 4% of the total body mass of humans; in adults weighing 65 kg , bone marrow accounts for approximately 2.6 kg...
death is caused by a dose of radiation between 2 and 10 gray and is characterized by the part of the bone marrow that makes the blood being broken down. Therefore production of red
Red blood cell
Red blood cells are the most common type of blood cell and the vertebrate organism's principal means of delivering oxygen to the body tissues via the blood flow through the circulatory system...
and white blood cells and platelets is stopped by division of precursor
Precursor (chemistry)
In chemistry, a precursor is a compound that participates in the chemical reaction that produces another compound. In biochemistry, the term "precursor" is used more specifically to refer to a chemical compound preceding another in a metabolic pathway....
stem cells ceasing (4.5 gray kills 95% of stem cells). The loss of platelet
Platelet
Platelets, or thrombocytes , are small,irregularly shaped clear cell fragments , 2–3 µm in diameter, which are derived from fragmentation of precursor megakaryocytes. The average lifespan of a platelet is normally just 5 to 9 days...
s greatly increases the chance of fatal hemorrhage. While the lack of white blood cells causes septicemia infections, the fall in red blood cells is minimal and only causes mild anemia
Anemia
Anemia is a decrease in number of red blood cells or less than the normal quantity of hemoglobin in the blood. However, it can include decreased oxygen-binding ability of each hemoglobin molecule due to deformity or lack in numerical development as in some other types of hemoglobin...
.
The exposure to 4.5 gray of penetrating gamma rays has many effects that occur at different times:
In 24 hours:
- vomitingVomitingVomiting is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose...
- diarrheaDiarrheaDiarrhea , also spelled diarrhoea, is the condition of having three or more loose or liquid bowel movements per day. It is a common cause of death in developing countries and the second most common cause of infant deaths worldwide. The loss of fluids through diarrhea can cause dehydration and...
These will usually abate after 6–7 days.
Within 3–4 weeks there is a period of extreme illness.
- severe bloody diarrhea, indicating intestinal disorders causing fluid imbalance
- extensive internal bleedingInternal bleedingInternal bleeding is bleeding occurring inside the body. It can be a serious medical emergency depending on where it occurs , and can potentially cause death and cardiac arrest if proper medical treatment is not received quickly....
- septicemia infections
The peak incidence of acute BM death corresponds to the 30 day nadir in blood cell numbers. The number of deaths then falls progressively until it reaches 0 at 60 days after irradiation. The amount of radiation greatly affects the probability of death. For example over the range of 2 to 6 gray the probability of death in untreated adults goes from about 1% to 99%, but these figures are for healthy adults. Therefore results may differ because of the thermal and mechanical injuries and infectious conditions.
Gastrointestinal death
Gastrointestinal death is caused by a dose of radiation between 10 and 50 gray. Whole body doses cause damage to epithelial cells lining the gastrointestinal tractGastrointestinal tract
The human gastrointestinal tract refers to the stomach and intestine, and sometimes to all the structures from the mouth to the anus. ....
and this combined with the bone marrow damage is fatal. All symptoms become increasingly severe causing exhaustion and emaciation
Emaciation
Emaciation occurs when an organism loses substantial amounts of much needed fat and often muscle tissue, making that organism look extremely thin. The cause of emaciation is a lack of nutrients, starvation, or disease....
in a few days and death within 7–14 days from loss of water and electrolytes.
The symptoms of gastrointestinal death are:
- gastrointestinal pain
- anorexia
- nausea
- vomiting
- diarrhea
Central nervous system death
Central nervous systemCentral 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...
death is the main cause of death in 24–48 hours among those exposed to 50 gray.
The symptoms are:
- vomiting
- nausea
- diarrhea
- drowsiness
- lethargy
- tremors
- deliriumDeliriumDelirium or acute confusional state is a common and severe neuropsychiatric syndrome with core features of acute onset and fluctuating course, attentional deficits and generalized severe disorganization of behavior...
- frequent seizureSeizureAn epileptic seizure, occasionally referred to as a fit, is defined as a transient symptom of "abnormal excessive or synchronous neuronal activity in the brain". The outward effect can be as dramatic as a wild thrashing movement or as mild as a brief loss of awareness...
s - convulsions
- prostrationProstrationProstration is the placement of the body in a reverentially or submissively prone position. Major world religions employ prostration either as a means of embodying reverence for a noble person, persons or doctrine, or as an act of submissiveness to a supreme being or beings...
- comaComaIn medicine, a coma is a state of unconsciousness, lasting more than 6 hours in which a person cannot be awakened, fails to respond normally to painful stimuli, light or sound, lacks a normal sleep-wake cycle and does not initiate voluntary actions. A person in a state of coma is described as...
- respiratory failureRespiratory failureThe term respiratory failure, in medicine, is used to describe inadequate gas exchange by the respiratory system, with the result that arterial oxygen and/or carbon dioxide levels cannot be maintained within their normal ranges. A drop in blood oxygenation is known as hypoxemia; a rise in arterial...
- deathDeathDeath is the permanent termination of the biological functions that sustain a living organism. Phenomena which commonly bring about death include old age, predation, malnutrition, disease, and accidents or trauma resulting in terminal injury....
Skin
The skinHuman skin
The human skin is the outer covering of the body. In humans, it is the largest organ of the integumentary system. The skin has multiple layers of ectodermal tissue and guards the underlying muscles, bones, ligaments and internal organs. Human skin is similar to that of most other mammals,...
is susceptible to beta-emitting radioactive fallout. The principal site of damage is the germinal layer, and often the initial response is erythema
Erythema
Erythema is redness of the skin, caused by hyperemia of the capillaries in the lower layers of the skin. It occurs with any skin injury, infection, or inflammation...
(reddening) due to blood vessel
Blood vessel
The blood vessels are the part of the circulatory system that transports blood throughout the body. There are three major types of blood vessels: the arteries, which carry the blood away from the heart; the capillaries, which enable the actual exchange of water and chemicals between the blood and...
s congestion and edema
Edema
Edema or oedema ; both words from the Greek , oídēma "swelling"), formerly known as dropsy or hydropsy, is an abnormal accumulation of fluid beneath the skin or in one or more cavities of the body that produces swelling...
. Erythema lasting more than 10 days occurs in 50% of people exposed to 5-6 gray.
Other effects with exposure include:
- 2-3 gray--temporary hair loss
- 7 gray--permanent epilationEPilationEPilation is the first full-length release from Brisbane musician Tara Simmons. Although a full-length, EPilation contains no new material and is a compilation of Tara's first two EPs Pendulum and All The Amendments...
occurs - 10 gray--itching and flaking occurs
- 10-20 gray--weeping blisterBlisterA blister is a small pocket of fluid within the upper layers of the skin, typically caused by forceful rubbing , burning, freezing, chemical exposure or infection. Most blisters are filled with a clear fluid called serum or plasma...
ing and ulceration will occur
Lungs
The lungLung
The lung is the essential respiration organ in many air-breathing animals, including most tetrapods, a few fish and a few snails. In mammals and the more complex life forms, the two lungs are located near the backbone on either side of the heart...
s are the most radiosensitive organ, and radiation pneumonitis can occur leading to pulmonary insufficiency and death (100% after exposure to 50 gray of radiation), in a few months.
Radiation pneumonitis
Pneumonitis
Pneumonitis or pulmonitis is a general term that refers to inflammation of lung tissue.Pneumonia is pneumonitis combined with consolidation and exudation...
is characterized by:
- Loss of epithelial cells
- EdemaEdemaEdema or oedema ; both words from the Greek , oídēma "swelling"), formerly known as dropsy or hydropsy, is an abnormal accumulation of fluid beneath the skin or in one or more cavities of the body that produces swelling...
- InflammationInflammationInflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process...
- Occlusions of airways, air sacs and blood vessels
- FibrosisFibrosisFibrosis is the formation of excess fibrous connective tissue in an organ or tissue in a reparative or reactive process. This is as opposed to formation of fibrous tissue as a normal constituent of an organ or tissue...
Ovaries
A single dose of 1-2 gray will cause temporary damage and suppress menstruationMenstruation
Menstruation is the shedding of the uterine lining . It occurs on a regular basis in sexually reproductive-age females of certain mammal species. This article focuses on human menstruation.-Overview:...
for periods up to 3 years; a dose of 4 gray will cause permanent sterility.
Testicles
A dose of 0.1 gray will cause low sperm count for up to a year; 2.5 gray will cause sterility for 2 to 3 years or more. 4 gray will cause permanent sterility.Cataract induction
The timespan for developing this symptom ranges from 6 months to 30 years to develop but the median time for developing them is 2–3 years.- 2 gray of gamma rays cause opacities in a few percent
- 6-7 gray can seriously impair vision and cause cataracts
Cancer induction
CancerCancer
Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...
induction is the most significant long term risk of exposure to a nuclear bomb. Approximately 1 out of every 80 people exposed to 1 gray will die from cancer and 1 in 40 people will get cancer. Different types of cancer take different times for them to appear:
- 2 years for leukemiaLeukemiaLeukemia or leukaemia is a type of cancer of the blood or bone marrow characterized by an abnormal increase of immature white blood cells called "blasts". Leukemia is a broad term covering a spectrum of diseases...
to appear - 20 or more years for skin cancerSkin cancerSkin neoplasms are skin growths with differing causes and varying degrees of malignancy. The three most common malignant skin cancers are basal cell cancer, squamous cell cancer, and melanoma, each of which is named after the type of skin cell from which it arises...
or lung cancerLung cancerLung cancer is a disease characterized by uncontrolled cell growth in tissues of the lung. If left untreated, this growth can spread beyond the lung in a process called metastasis into nearby tissue and, eventually, into other parts of the body. Most cancers that start in lung, known as primary...
In utero effects
1 gray dose of radiation will cause between 0 and 20 extra cases of perinatal mortalityPerinatal mortality
Perinatal mortality , also perinatal death, refers to the death of a fetus or neonate and is the basis to calculate the perinatal mortality rate. Variations in the precise definition of the perinatal mortality exist specifically concerning the issue of inclusion or exclusion of early fetal and...
, per 1,000 births and 0-20 cases of severe mental sub normality. 0.05 gray will increase death due to cancer 10 times, to 5 per 1,000. An antenatal dose of 1 gray in the first trimester causes the risk of fatal cancer to increase to 100%.
Transgenerational genetic damage
Exposure to even relatively low doses of radiation generates genetic damage in the progeny of the irradiated organisms. This damage can accumulate over several generations. http://www.ncbi.nlm.nih.gov/pubmed/16215755Infectious diseases resulting from nuclear attack
The main long term effects of a nuclear blast are infectious diseaseInfectious disease
Infectious diseases, also known as communicable diseases, contagious diseases or transmissible diseases comprise clinically evident illness resulting from the infection, presence and growth of pathogenic biological agents in an individual host organism...
s caused by contaminated water, untreated sewage
Sewage
Sewage is water-carried waste, in solution or suspension, that is intended to be removed from a community. Also known as wastewater, it is more than 99% water and is characterized by volume or rate of flow, physical condition, chemical constituents and the bacteriological organisms that it contains...
, crowded living conditions, poor standard of living, and lack of vaccine
Vaccine
A vaccine is a biological preparation that improves immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism, and is often made from weakened or killed forms of the microbe or its toxins...
s in the aftermath. These diseases include:
- DysenteryDysenteryDysentery is an inflammatory disorder of the intestine, especially of the colon, that results in severe diarrhea containing mucus and/or blood in the faeces with fever and abdominal pain. If left untreated, dysentery can be fatal.There are differences between dysentery and normal bloody diarrhoea...
- Infectious hepatitis
- SalmonellosisSalmonellosisSalmonellosis is an infection with Salmonella bacteria. Most people infected with Salmonella develop diarrhea, fever, vomiting, and abdominal cramps 12 to 72 hours after infection. In most cases, the illness lasts four to seven days, and most people recover without treatment...
- CholeraCholeraCholera is an infection of the small intestine that is caused by the bacterium Vibrio cholerae. The main symptoms are profuse watery diarrhea and vomiting. Transmission occurs primarily by drinking or eating water or food that has been contaminated by the diarrhea of an infected person or the feces...
- Meningococcal meningitis
- TuberculosisTuberculosisTuberculosis, MTB, or TB is a common, and in many cases lethal, infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis. Tuberculosis usually attacks the lungs but can also affect other parts of the body...
- DiphtheriaDiphtheriaDiphtheria is an upper respiratory tract illness caused by Corynebacterium diphtheriae, a facultative anaerobic, Gram-positive bacterium. It is characterized by sore throat, low fever, and an adherent membrane on the tonsils, pharynx, and/or nasal cavity...
- Whooping cough
- Polio
- PneumoniaPneumoniaPneumonia is an inflammatory condition of the lung—especially affecting the microscopic air sacs —associated with fever, chest symptoms, and a lack of air space on a chest X-ray. Pneumonia is typically caused by an infection but there are a number of other causes...