Depleted Uranium

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the small mass difference between atoms of the two isotopes. U-238 and. U-235. Uranium ... quantity of Uranium in the kidney can impair renal function, and any ...

Investigation of Depleted Uranium in South West Region of IRAQ and Assessment of It’s Biological Effects By

SUHA ADIL KASIM AL-ANNI Supervisor Dr. Abdulredha S. Al- Sa’idi 2003

Supervisor Dr. Athab T. Al- Kinani

Natural Uranium A radioactive and chemical element, represent by U symbol. Uranium was isolated in 1789 by a German chemist “Martin Heinrich Klaproth” in a samples of pitchblende from Saxony. It was named after the planet Uranus, which had been discovered 8 years earlier.

Natural Uranium is heavy element found in nature in different form and the human body contains (90µg) as average result from food chain about 66% are found in the Skeleton, 16% in the Liver, 8% in the Kidneys, and 10% in other tissues. The average annual intakes of Uranium by adults are estimated to be (460µg) from ingestion and (0.59 µg) from inhalation.

DU Production: Mining to Conversion

Uranium Enrichment Is a physical process, usually relying on the small mass difference between atoms of the two isotopes U-238 and U-235.

Depleted Uranium Depleted Uranium (DU) is a by-product of the Uranium enrichment process used to enrich Natural Uranium ore for use in nuclear reactors and in nuclear weapons. PERCENT IN URANIUM ISOTOPES NATURAL ENRICHED

DEPLETED (0.5 %)

DEPLETED (0.35 %)

U-238

99.2739

97.01

99.745

99.65

U-235

0.72

2.96

0.250

0.35

U-234

0.0057

0.03

0.005

0.0018

0.0072

0.0305

0.0025

0.00351

235

U/238U

Health Effects of Depleted Uranium After inhalation or ingestion, Uranium can be transported around the body in the blood stream, thus, exposing other organs and blood cells to it’s carcinogenic effect. In inhalation, toxic and radioactive particles are trapped permanently in the lung increasing the risk of cancer, and then travel in the blood stream and deposited in the brain, kidneys, bone, reproductive organ, muscle, and spleen. In ingestion, DU accumulates in bone and kidney. A large quantity of Uranium in the kidney can impair renal function, and any amount can induce renal cancer.

Atmospheric Dispersion When a radioactive effluent is released to the atmosphere it will become dispersed by the procession of atmospheric turbulent diffusion. The estimation of dispersion is commonly approached by the statistical theory of turbulent diffusion or by solving the diffusion equation.

Radiation Exposure The act or condition of being subject to irradiation. Exposure can be either external exposure or internal exposure (due to inhalation, ingestion, dermal contact, or injury).

Radiation Risks Assessment Risk can either refer to the probability of occurrence of an event, or to the consequences of an event if it occurs. A third possibility is a combination of probability and consequence. It should be possible to express the risk (consequence) as “insignificant” or “significant” bearing in mind the basis for the comparisons drawn. In this report, the consequences of radiation are considered insignificant for doses less than (1 mSv) per year (or per infrequent event) and significant for doses higher than (1 mSv).

Aim of the Study The purposes from this study are: 1-Detection of Depleted Uranium in South West region of IRAQ, and the effects of DU in soil contamination. 2-Determination the dominant wind blown direction, and the dispersion of contamination.

3-Estimation the internal radioactive doses that result from the inhalation and ingestion of the contaminated food and drinking. 4-Evaluation the risk factor on people living in that region due to contamination and conjecture the number of people get cancer and die in these region.

Gamma Spectroscopy The outstanding advantage of gamma ray spectrometry is the ability to measure gamma emitters directly in the original sample without the need for chemical separations. Gamma rays spectrometry allows both: •Qualitative analysis: -for determining the types of radionuclides in the sample. •Quantitative analysis: -for determining concentrations of radionuclides in the sample.

the

Gamma Spectrometry System Shield of Lead HpGe detector & preamplifier

Printer Linear amplifier

Detector bias supply

Personal Computer Analyzer Data storage

Spectrometry Calibration The detector has been calibrated in Two ways of calibration •Energy calibration •Efficiency calibration

Estimation of Natural Radionuclides in the Samples •Determinatiom the radionuclides that result from (U – 238) •Determination the radionuclides that result from (U – 235)

•Determination Potassium nuclide (K-40)

Measurement of Specific Radioactivity The specific radioactivities for the chosen radionuclides in each sample were calculated by using the following equation: -

Area / t  B.G SpecificAc tivity ( Bq / kg)  I %. %.m Area = Net area under the peak (counts). t = Time of count (sec).

B.G = Background. I% = The percentage of gamma intensity.  % = The percentage of the efficiency.

m = Weight of the sample (kg).

The Percentage between (235U/238U) There are two methods used to calculate the percentage between (235U/238U): -

A-The method that used by International Committee to detect the (Depleted Uranium) in Kosovo according to the following equation : -

Ru = (0.72 – 0.52 X) / (99.2745 + 0.5255X) X = The quantity of Depleted Uranium in soil samples. Ru = The percentage between (U-235/U-238).

B-The method that used by International Atomic Energy Agency (IAEA) to detect the (Depleted Uranium) according to the following equation : -

rm = qF (q and F) values calculate by following equation q

F





P2 c P1U

 E2   E    1

P1Ra 1 f P3

 E1   E3

a

N1 N2 a

 N3   N1

Drawing of Wind Rose According to the frequency percentage that obtained from the Iraqi Meteorological Organization (IMO) we draw the wind rose. By drawing centric cycles and dividing it into eight sections by lines. These lines represent the wind directions (N, NE, E, SE, S, SW, W, and NW). The length of the line depends on the value of the frequency percentage.

Calculation of Contamination Dispersion The concentration of pollutants in the air (Ca) has been calculated by using Gaussian plume diffusion model, which is as follow: -

Ca 

Q U Y  Z

Q = Pollutants emission rate (Bq/s). U = Wind speed (4 m/s), according to the data that obtained from Iraqi Meteorological Organization (IMO).  = Constant percentage (3.14). y , z = Dispersion coefficients in air (m2), which are a function of down wind distance (x) and atmospheric stability.

Dosimetric Model for the Respiratory System The dosimetric model enables the resulting doses to each part of the respiratory system to be calculated: -

•Parts of respiratory system: A-Nasopharyngeal region (N-P): R1(t)=IDN-p (Fa e- (a +R) t+ Fb e- (b +R) t) B-Trachiobronchial region (T-B): R2(t)=IDT-B (Fc e- (c +R) t+ Fd e- (d +R) t) C-Pulmonary region (P): R3(t)=IDP (Fe e- (e +R) t+ Ff e- (f +R) t +Fg e- (g +R) t+ Fh e- (h +R) t)

I = The rate of inhalation of activity of the radionuclides at time (t) in (Bq/day), which calculated by using the following equation: -

I = Cair x RB Cair = Air activity concentration (Bq/m3). RB = Breathing rate (m3/day).

Dosimetric Model for the Gastrointestinal System The dosimetric model is based on biological model that G.I system is taken to consist of the 4 sections for the purposes of radiological protection.

•Parts of gastrointestinal system: A-Stomach region (ST): -

R1(t)=Ao e-(ST +R) t

B-Small intestine region (SI): -



AST ST R2(t )  e SI R B t  e ST R t ST  SI  B



C-Upper large intestine region (ULI): -

R3(t )



ASI SI  e ULI R t  e SI R t SI  ULI



D-Lower large intestine region (LLI): -

R4(t )

AULI ULI  e LLI R t  e ULI R t ULI  LLI





Ao= The rate of ingestion of activity of the radionuclides at time (t) (Bq/day), which is calculated by the following steps: -

1-Estimated of radionuclides concentrations that transferred from soil to plant, which is done by using the equation below: -

CV = BV CS CV = The concentration of radionuclide in plant derived food (Bq/kg). BV = soil to plant transfer factor.

CS = The concentration of radionuclide in soil derived food (Bq/kg).

2-Estimated of radionuclides concentrations that transferred from plant to animals’ product (meat and milk), which is done by using the most general type of models that have been used to find the degree of transfer of radionuclide from feed, forage and/or drinking water to animal products, which is as follows:-

CP = FP (CV QV) CP = The average concentration of the radionuclide in type (P) animal product (Bq/kg for meat) and (Bq/L for milk).

FP = The transfer factor of the radionuclide from daily intake to type (P) animal product (d/kg for meat) and (d/L for milk). CV = The concentration of radionuclide in forage or type (V) feed ingestion by the animal (Bq/kg).

QV = The average daily intake of contaminated forage or type (V) feed ingestion by the animal (kg/d).

3-Estimated of radionuclides concentrations that transferred from animals’ product (meat and milk) to human by multiplying the average concentration of the radionuclide in type (P) animal product by the average daily intake of human from contaminated animal product (kg/d for meat) and (L/d milk).

Calculation of Total Dose We calculated daily inhalation and ingestion doses by using the following equation: EF = AC. DCF EF = The Effective dose (Sv/day). AC = The radioactivity that be taken through inhalation or ingestion (Bq/day). DCF = The dose conversion factor (Sv/Bq).

Calculation the Possibility of Death To estimate the probability of death occurrence due to cancer, ICRP use the following method: A-In case of people of different age expose to internal doses, the collective effective dose is used: Collective effective dose (man.Sv)= The average of internal radioactive doses (Sv) x Number of expose people (man)

B-The possibility of death that occur due to cancer: The possibility of death (man.year)= Collective effective dose (man.Sv) x Probability coefficients for cancer (1/Sv)

Depleted Uranium has been detected in two regions that located in the South West of IRAQ. These regions are Al-Nukhaib and Al-Salman.

Many samples are collected from these two mentioned regions. From these samples we chose five samples from Al-Nukhaib and five samples from Al-Salman, which are more suitable and more benefit in this research.

The spectrum of SA5.SPM

The spectrum of SA4.SPM

The Radioactivity and the percentage between 234Th/ 234mPa

The percentage between 235U/238U according to Kosovo method The percentage between 235U/238U that calculated according to Kosovo method shown that the percentage of Depleted Uranium (DU) in the samples are 0% for SA5.SPM, and SA9.SPM; 50 % for SA2.SPM, and SA3.SPM; 100 % for SA1.SPM, SA4.SPM, SA6.SPM, SA7.SPM, SA8.SPM, and SA10.SPM.

The percentage between 235U/238U according to Vienna method rm(Unat)

DU is detected in samples when the values of Ru (rm) below 0.007 and not detected when the values of Ru (rm) above 0.007.

235U/238U

according to Vienna and Kosovo method

When we compare the results of 235U/238U we see that there is an approximation in the percentage that obtained according to International Atomic Energy Agency method (Vienna) with the percentage that obtained according to Kosovo method.

The wind rose according to the frequency % for Al-Nukhaib and Al-Salman regions

The concentration of contamination dispersion to the surrounding areas for Al-Nukhaib region

The concentration of contamination dispersion to the surrounding areas for Al-Salman region

The summation of inhalation doses for 238U for moderate respiration

The summation of inhalation doses for 235U for moderate respiration

The summation of ingestion doses for 238U for meat

The summation of ingestion doses for 235U for meat

The summation of ingestion doses for 238U for milk

The summation of ingestion doses for 235U for milk

The total radioactive inhalation and ingestion doses

Possibility of Death Incidence The incidences of death depending on the total internal doses that effect the human bodies from both 235U and 238U. The total radioactive doses that the human bodies exposed are depend on the percentage of contamination.

The number of death incidence due to stochastic effects

The probability of the fatal cancer for individual tissue and organ

Aggregated detriment for individual tissue and organ

After broad observation to this study we would conclude the following: 1-This study confirm that there is a contamination in the South West region of our country due to the presence of DU near the destroy vehicles and tanks. 2-The dispersion of contamination to different directions and dimensions has environmental danger to the people. 3-According to the data that obtain from I.M.O, the dominant wind blown in these two regions are from NW direction, so most contamination will pass to SE direction. 4-The radioactive doses are less than the permissible dose for samples that are far from contamination, but for the samples that are near the contamination the radioactive doses is higher than the permissible dose.

5-The death incidence is high for the contaminated samples, and low for samples that are less contaminated.

1-Performing similar research in all the government of Iraq to check the extension and the spreading of the radioactive pollution. 2-The destroyed artilleries stockyard is still consider a source of pollution to these areas in addition to many other destroyed armors that are still scattered in different locations surrounding the study areas, So these artilleries must be removed from these areas. 3-Series steps must be taken and great efforts are required for the clearing up of this contamination that has resulted from the use of DU in these two regions during 1991. 4-Further studies should be conducted to investigate the biological health effects on plants, animals, and humans resulted from the contamination and to calculate the effective doses resulting from the radioactive pollutants. 5-Investigation the population health condition in the study area through evaluating the increase of updated cancer and related disease among people due to exposed to the radiation.

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