Estimated the concentration of 238U, 232Th and 40K in flour samples of Iraq markets

Flour is a nutritious type of food that is widely consumed by various age groups in Iraq. This study investigates the presence of long-lived gamma emitters in different type of flour in Iraqi market. Uranium (238U), Thorium (232Th) and Potassium (40K) specific activity in (Bq.kg−1) were estimated in (15) unique kinds of flours that are accessible in Iraqi markets. The gamma spectrometry method with a NaI(Tl) detector has been utilized for radiometric measurements. Likewise right now have determined the internal hazard index. It is found that the specific activity in Flour samples were varied from (13.73± 1.89) Bq.kg−1 to (2.60± 0.30) Bq.kg−1 with an average (8.75) Bq.kg−1 for 238U, For 232Th From (67.79± 0.44) Bq.kg−1 to (9.96± 0.14) Bq.kg−1 with an average (21.88) Bq.kg−1 and for 40K from (2680.74 ± 23.60) Bq.kg−1 to (283.70± 3.41) Bq.kg−1 with an average (133.09) Bq.kg−1. Also, it is found that the Outdoor and indoor annual effective absorbed dose equivalent also (Hin) hazard indices was (0.302±0.014) and average annual committed effective dose(0.2205±0.030) mSv.y−1 in the flour samples. This study prove that the natural radioactivity and radiation danger records were low also estimated cancer risk has no significant health hazard in Iraqi Flour.


1.Introduction
Characteristic radioactivity is brought about by the nearness of Natural occurring radioactive matter (NORM) in the environment. Instances of normal radionuclides incorporate isotopes of Potassium ( 40 K), Uranium ( 238 U and its decay series), and Thorium ( 232 Th and its decay series). In Health Physics, radiation dosimetry is characterized as the estimation of radiation levels that sway on human health [1].The world population is subjected to different types of radiation sources including artificial radiation (15%)and natural radiation (85%) which contains food and drinks (11%). This may give a chance to the contamination of radioactive materials [2]. In fact, NORM can be moved from soil to plants. Thus, each sort of food may have some amount of radioactivity in it [3]. The world population is subjected to different types of radiation sources including artificial radiation, these radionuclides are commonly present in air, soil, and Flour in various sums and levels of movement [4]. Normal radionuclides are found in earthly and oceanic evolved ways of life, with consequent exchange to people through ingestion of nourishment. As such, worldwide endeavors were united cooperatively to apply sufficient strategies in researching radionuclides in food [5], and to set basic rules to secure against elevated levels of inner presentation that might be brought about by food consumption [6].
Since Flour is one of the essential food that is consumed in Iraqis daily lives, the longing to build up a national standard of radioactivity exposure from various kinds of Flour types that available in Iraq markets is very critical, Flour is a powder made from the grinding of wheat used for human consumption. Also, the "Staff of Life", has been an essential commodity to human existence through the centuries and is currently the most widely consumed staple food [7]. Moreover, numerous studied were conducted worldwide to research natural radionuclides in food consumed in various pieces of the world [8,9]. Another study on vegetables .The annual effective dose due to intake of these radionuclides through ingestion of vegetable samples was estimated to assess radiological risks, the average annual effective dose was found as 213.27 μ Sv y −1 [10] .Radioactivity measurements in staples are very important for checking radiation hazards on human health. where the another study in Iraq found the dose due to consumption of fish by the public has also been determined and it has been below the dose limit recommended by World Health Organization [11,12]. This paper aims to create radiological baseline data of the hazard radiation in involved foodstuff (Flour samples in Najaf/Iraq).
To achieve this aim, the radioactivity levels and radiation hazard indices of consumed Flour types in Najaf, Iraq are calculated and investigated. Since Flour is famous among all ages, the present study centers around limited the natural radioactive in this nourishment

2.Materials and Methods
collection and Preparation (15) samples of the most available kinds of Flour were gathered from the local markets in Iraq to measure natural activity. The types of samples are listed in Table (1) where was the Wight of each sample was 600gm. After collection, each Flour sample was kept in a plastic bag and marked by its name. After collection, these samples were packed in a 1 L polyethylene plastic container of constant volume to arrive at a geometric homogeneity around the Detector, then the respective net weights were measured and recorded with a high sensitive digital weighing balance with a percent of ±0.01%. the plastic container were sealed with adhesive tape, the samples were kept in container for one month to confirm the radioactive equilibrium to take place between the series 222 Rn and their short lived progenies [10].  Characteristic radioactivity levels were estimated utilizing a gamma spectrometer which incorporates gamma multichannel analyzer outfitted with NaI(Tl) indicator of crystal dimension(3"*3"). The gamma spectra were analyzed using the ORTEC Maestro-32 information procurement and analysis system. The detector had coaxial closed-facing geometry with the following specifications. The calculated resolution is 7.9% f or energy of ( Calculation of Activity. Since the counting rate is proportional to the amount of the radioactivity in a sample, is the Activity Concentration of each radionuclide in Bq.kg -1 ,which can be determined as a specific activity as the follows [13]: where is the specific activity of each radionuclide in Bq.kg -1 , C _the count rate in cps f or sample, the count rate in cps for background, ε γ and are detection efficiency and emission probability of γ-ray , is the checking time and is the mass of the sample in Kg .
Where , ℎ and are the specific activity of 238 U, 232 Th and 40 K respectively.
The internal hazard index has to be less than one as well to provide safe radionuclide levels in all samples .In the event that the determined estimations of files are more prominent than solidarity, radioactivity may make hurt the populace. The annual effective dose equivalent from outdoor terrestrial gamma radiation is [16]: .
Where DCFi is the dose convection factor for ingestion, for each radionuclide (i.e., 4.5 × 10 - Average annual committed effective dose(AACED) measurements The AACED due to the ingestion of naturally occurring radioactive materials (NORMs) in was estimated according to Equation 9, AACED for an individual is directly proportional to the consumption rate of the  [18].

3.Result and Discussion
The specific activity of 238 U, 232 Th and 40 K in various types of Flour samples has been measured as appeared in Table (  There is a variety in the specific activity of radionuclides in different Flour samples, in the sample (F 9 ) which is Iraqi (Al rahab company) has height concentration for( 40 K and 232 Th) while (F 13 ) which is Turkish (Ameen) was height for ( 238 U). The results obtained show that the specific activity of 238 U, 232 Th and 40 K in all Flour samples seemed lower than recommended limit of UNSCEAR (2008) .we noted from our results that all average is higher than values in another publishers [6,20].
The Outdoor annual effective dose equivalent, Indoor annual effective dose equivalent and the Total annual effective dose equivalent due to 238 U, 232 Th and 40 K in different kinds of Flour samples has been measured as shown in Table (3) and Figures 4 -6 respectively. Where was in sample (F 10 ) Turkish(soft) was height in all this parameters while was low in sample (F 5 ) Iraqi (Al Ihasan).

Excess lifetime Cancer risk:
The risk of cancer due to radiation effects which is called excess lifetime cancer risk (ELCR) can be calculated from the following equation [21] ELCR =(AACD) Sv.y -1 * Rf (Sv -1 ) Where, (AACD) the annual committed effective dose of the average duration for adult members of public and risk factor respectively. The value of risk factor (Rf) in the public is 0.05 per Sievert as recommended by ICRP for stochastic effects [22].The average annual committed effective dose for the measured flour in this study, 0.2205mSv, is used to estimate cancer risk for an adult person using the equation (11) above was estimated to be 0.0110 mSv, which gives a risk factor of 5.512*10 -4 .The estimated values are significantly less than the ICRP cancer risk of 2.5 × 10 -3 based on annual dose limit of 1mSv for general public. Which mean the average of all samples is saving healthy.

4.Conclusions
The current study is the significant at the national level to study radioactivity of Flour that is available in Iraqi markets. It is found that utilization of Flour as the staple is safe for all ages of individuals in Iraq. Potassium ( 40 K) specific activity in (Bq.kg -1 ) were very high compared with other studies [23] ,especially in sample F 9 which may be because the type of soil or Fertilizers which added for soil containing potassium, this work will help in building up a gauge of radioactivity exposure to the public from ingestion of foodstuff. Also have been found the outdoor and indoor annual effective absorbed dose equivalent derived from activity Internal radiation hazard and average annual committed effective dose for Flour samples were the results fall within the permissible limits internationally that mean we estimated from this study the cancer risk has no significant health hazard and Iraqi Flour which used in markets are radiologically safe, as per international standards.