DETERMINATION OF HEAVY METALS CONCENTRATION OF LOCAL AND IMPORTED WHEAT GRAINS STORAGE AND WHEAT FLOUR IN SOME SILOS of BAGHDAD CITY

The aim of this study was to estimate the levels of some toxic heavy metals such as (Cd, Pb,Cr,Ni,Zn,Cu,Fe,Co,As)by using the X-Ray fluorescence .in a total of forty-one samples of wheat grains which were (local, American, Australian, Canadian and mixing mills) samples collected randomly and seasonally from three silos in Baghdad ,also wheat flour collected from mills related to the manufactured of grains of each silo. The results showed that the levels of (Cadmium, Lead and Chromium) were surpassed the permissible safe limits according to FAO/WHO (2001).It was found that the highest concentration of cadmium detected in wheat flour in AL Dora silo for summer and spring seasons were 12.6mg/kg, as well as the high level of lead 1.021mg/kg detected in AL Dora silo in local wheat for winter and summer seasons and wheat flour for spring season, also in Australian wheat for spring season in Taji silo. Finally, the high value of chromium content was in wheat flour in Taji silo for spring season (4.686) mg/kg. Generally, analysis of these data shows significant effects (P≤0.05) of most samples analyzed for Cd >Pb >Fe >Zn >Cu >Ni >Cr >Co while AS show no significant difference in all samples. Keyword: X-Ray fluorescence, toxic, chromium, mixing mills, Arsenic ةيقارعلا ةيعارزلا مولعلا ةلجم 2021 : 52 ) 5 :) 1139 1149 نارمعو يدهم ت ـــــــ يكرت ريدق ـــــــ ز ضعب عملا ـــــــ يقثلا ندا ــــــ يف ةل بح ــــــ طنحلا بو ـــــــــ يلحملا ه ـــــــ تسملاو ه ـــــــ يقدو هدرو ـــــــــ لا ق ــــ مق ــــــ خم يف ح ـــــــ نزا صلا ضعب ــــــــ يف عماو نيدم ـــــــــــ ة غب ـــــــــ داد . غر ــــــــــــ ص د ـــــــ هم حلا ــــــ يد ف ـــــــ ظاك هزئا ــــــــ ع م ــــــــ نا رم ثحابلا تسا ـــــــــــ دعاسم ذا تسملا ــ خ ــــ صل هسا ردلا فدهت هيلاحلا تايوتسم ديدحت ىلا لثم هماسلا هليقثلا نداعملا ضعب ( مويمداكلا ، ،صاصرلا ،موركلا ،لكينلا ،كنزلا ،ساحنلا ،ديدحلا ،تلبوكلا )خينرزلا ،هيلحم(تناك ىتلا حمقلا بوبح نم هنيع نيعبراو ىدحا يف ،هيكيرما ،هيلا رتسا هيدنك )نحاطملا ةطلخو مادختساب هينيسلا هعشلاا ناضم عمج مت، جذامنلا قيقد كلذك ،دادغب يف عماوص ثلاث نم ايمسومو ايئاوشع ،مويمداكلا( تايوتسم نا جئاتنلا تحضوا .هعموص لك يف بوبحلا عينصتب هقلعتملا نحاطملا نم هعمج مت يذلا حمقلا )موركلاو صاصرلا هيملاعلا هحصلا همظنمو هعا رزلاو هيذغلاا ةمظنمل اقفو اهب حومسملا هنملأا دودحلا تزواجت دق ( 2001 ) لا قيقد يف هفاشتكا مت مويمداكللزيكرت ىلعا نا تدجوو، ناك عيبرلاو فيصلا مسومل هرودلا ةعموص يف حمق 12،6 ، مغك/غلم صاصرلل عفترملا ىوتسملا ناكو 1،021 مغك/مغلم حمقلا قيقدو فيصلاو ءاتشلا مسومل يلحملا حمقلا يف هرودلا ةعموص يف سلاا حمقلا يف كلذكو، عيبرلا مسومل ،ا ريخاو .يجاتلا ةعموص يف عيبرلا مسومل يلا رت يف موركلا ىوتحمل هيلاعلا هميقلا تناك يجاتلا ةعموص يف حمقلا قيقد عيبرلا مسومل 4،686 لكشب. مغك/مغلم ع ما هيونعمو هريبك تا ريثات تانايبلا هذه ليلحت رهظي، ل اهليلحت مت ىتلا تانيعلا مظعمل ( لكين>ساحن>كنز>ديدح>صاصر>مويمداك مورك> تلبوك> ) قرف يا خينرزلا رهظي لا امنيب تانيعلا عيمج يف يونعم . ملكلا ـــــــ ملا تا ـــــ يحاتف ـــــ :ه هينيسلا هعشلاا ناضم ، موركلا ،مومسلا . خينرزلا ،نحاطم هطلخ ، Received:13/3/2020, Accepted:9/6/2020 Iraqi Journal of Agricultural Sciences –2021:52(5):1139-1149 Mahdi & Omran 1140 INTRODUCTION Wheat is one of the most common staple food crops for more than one-third of the world’s population, it provides on average one-fifth of the total calorific input of the world’s population (4). Compare with other grains, Wheat contain a high proportion of protein, fat and fiber, also it is abundant in potassium, phosphorus, manganese, zinc, vitamin B6, folate, thiamine, riboflavin and niacin(7). The consumption of Food was identified as the main exposure pathway to Arsenic (As), cadmium (Cd) and lead (Pb), than other pathways of exposure, as inhalation and dermal contact (28). Moreover, these above elements can cause adverse effects on humans even at very small concentrations while exposure occurs over a long time period (19). The health risk associated with the ingestion of toxic metals can be valued via carcinogenic and non-carcinogenic ways. The Hazard Quotient (HQ) is a non-cancer risk valuation which is calculated thru using the ratio between the estimated of pollutant dose and the dose below level for which there will not be any risk noticeable (23). Majority of heavy metals accumulate in wheat organs reserved in glume, stem, and leaf after roots, and followed by grains, indicating that heavy metal was accrued from atmospheric dust more than to another sources (20). The stress of Cadmium, lead, Arsenic, mercury, and Chromium on wheat crops and components in the farmland and Wheat Consuming is regarded to be one of the main sources of heavy metals intake for individuals, whose can affect human health (21). The aim of this study is to determine the concentration of heavy metals (pb ,Zn,Hg,Fe,Cr,Co,Cd,Sn,Cu,As,Ni) in a local and imported wheat grains storage and wheat flour that may be found in some Silos of Baghdad. MATERIALS AND METHODS Description of the state of wheat grain stores and collection of samples The wheat grain stores of (Al Dora silo and Taji Silo) were a warehouse with cyclone dust and scattered grain residues on the ground of store, as well as the present of animal waste residues from birds and rodents, the aeration of the stores in silos were poor. On the other hand the silo of AlRusafa where the warehouse with average cleanliness and aeration also. As for the mills belonging to the General Company for the manufacture of grain, the stores were fairly clean and the flour material was supplying after grinding immediately.For each sampling one kg. of wheat grain and flour were put into sterile polyethylene bags and seal properly, amount from each sample discrete and divided into two parts which preserved in a sterile plastic containers, to estimate the chemical properties (heavy metals). Samples were transported to the laboratory at 25°C until analysis were performed. X-ray fluorescence XRF is emerging as an appropriate method for speedy quantification owing to, the nondestructive nature of analysis heavy metals in vegetables and other foodstuff, as contemporary study revealed that lead and other heavy metals are absorbed and transported from the soil into consumable vegetable tissues (12). The principle of XRF is simple: when an X-ray emission from a radioactive source strikes a sample, the X-ray can be either absorbed by atoms or scattered through the material. The atoms after absorption becomes “excited” and release a characteristic X-ray which energy level is matchless to the element impacted by the incident X-ray, this characteristic X-ray emission is invited X-ray fluorescence, or XRF. The separate energy measurement of the X-ray emitted is used to determine the types of minerals present, and the measurement of the number of X-ray emitted supplies a quantitative indication of the concentration of the metal present in sample. That confirmed that each of the atomic elements it is found in a sample that produces a unique set of distinctive X-rays that are a fingerprint of the specified element (5). Preparation and sample analysis Wheat grain samples were collected from silos, 10g of each of them were oven dried at around 70°C, and left to cool at room temperature 25 °C. The dried mass of each sample was grounded to fine powder using grain miller (BraBenDer company, Germany origin), preserved in a sterile plastic container with identification mark label until analysis. Three grams prepared of the powder samples Iraqi Journal of Agricultural Sciences –2021:52(5):1139-1149 Mahdi & Omran 1141 were weighed and pressed into pellets, the pellets were used for the determination of heavy metals such as(Hg , Pb ,Co, Cr, Fe, Cd, Ni, Ar ,Ag, Sn, Cu) levels were carried out using X-ray fluorescence spectrometry(Ametek company, Germany 2010 in origin) according to methods described previously (2) . Statistical analysis Statistical analysis (25) program was used to reveal the effect of differences agents on study parameters. LSD test (Least significant difference) was used for a significant difference for comparison between means. Correlation coefficient between traits was calculated. RESULTS AND DISCUSSION Cadmium (Cd) From the results obtained in this study, show in Figure1, the concentration value of cadmium in all samples analyzed of wheat grains and wheat flour ranged from (0.4-12.6) mg/kg=ppm. The highest concentration values detected in wheat flour and Australian wheat grain samples in Al Dora silo for summer and spring seasons which were 12.6 mg/kg and 12.1mg/kg respectively. While, the lowest concentration of Cd was detected in wheat flour samples and local wheat in Al Dora silo and AlRusafa silo for spring season and summer season respectively, the values were 0.4mg/kg and 0.5mg/kg respectively. These values of Cd in all samples analyzed were found to be above the permissible limits of 0.2mg/kg by FAO/WHO 2001 codex alimentarius commission(11).Statistical analysis revealed (Tabl11)that the means differed significantly at probability (P≤0.05) in the levels of Cd content in all samples analyzed of wheat grains and wheat flour in three silos for three seasons, high significant differed was observed in Al Dora silo for spring season which was (3.52*) and within the same sample of wheat flour LSD value was (2.87*). Cd is highly toxic non-essential elements and it does not have role in the biological process in living organisms, even lower concentration of Cd in the food chain could be harmful to living organisms (15).Furthermore, these results were agreed with study conducted by Chandra et al., 2009 found Cd content was1.06 mg/kg in wheat grains with soil irrigated with industrial wastewater (6). In previous studies found that application of sewage sludge to fields can an alternative to manure addition which lead to accumulation of cd in cereals. Moreover, Cadmium content of wheat grain or flour is influenced by several factors such as annual variation, cultivar differences, genetically and regional variations. Regional differences found in cadmium level are mainly affected by cadmium deposition via the atmosphere, soil fertilization and soil properties such as soil type, pH, origin and soil cadmium content .Also soil salinity enhances Cd uptake of many crops(9). Figure 1. The effect of location, season and type of wheat on cadmium conc Lead (Pb) the concentrations of lead in various samples of the wheat analyzed were ranged (0.092-1.021)mg/kg, shows in Figure 2. the maximum concentration of pb was detected in Al Dora silo in local wheat for winter and summer seasons and wheat flour for spring season which value was 1.021 mg/kg, furthermore the same value was detected in local wheat for winter season, in Australian wheat for spring season in Taji silo and mixing mills in Al Rusafa silo for summer season. While, the minimum level concentration of pb was detected in the local wheat sample in Taji silo for spring season which value was0.092 mg/kg. These values of pb in most samples analyzed were found to be above the permissible limits of 0.2mg/kg by (FAO/WHO) Codex alimentarius commission(11), except in Taji silo was detected in wheat flour sample for winter season 0.185 mg/kg, local wheat 0.092 mg/kg for spring season, mixing Mills for summer season 0.185 mg/kg, also in Al Rusafa silo Iraqi Journal of Agricultural Sciences –2021:52(5):1139-1149 Mahdi & Omran 1142 sample of wheat flour 0.186 mg/kg for winter season, finally in local wheat 0.185 mg/kg for summer season. That ingestion of lead is harmful at both high and low levels especially for the most sensitive populations (fetuses and young children). Chronic exposure to lead may cause birth defects, mental retardation, psychosis, hyperactivity, shaky hands, muscular weakness, paralysis (beginning in the forearms) and even death (26). Statistical analysis revealed (appendix2)that the means differed significantly at probability (P≤0.05) in the level of pb content in most samples of wheat grains and wheat flour analyzed, highest significant differences were detected in Al Dora silo for winter season (0.883*) and within the same samples of mixing mills were (0.723*).While, that the means didn’t differed significantly in the levels of pb contents were observed in Taji silo for summer season, and AlRusafa silo for both winter and spring seasons. These results agreed with previous study was conducted in A ( Table 2)dis Ababa which reported that pb level content in wheat grains was 1.02 mg/kg, while high value of pb content was detected in barley which was 2.23 mg/kg (13).These results were in disagreement with the study conducted by Shobha and Kalshetty, 2017 in India (27), which pb content ranged from (0.08-0.163) mg/kg. The main factor that affects the high content of lead in grain is absorption through air pollution as a result of the pollution from the highway traffics which can affect the irrigation water or farm soil of the plants, and related to the milling plates in both dry and wet conditions (8). Figure 2. The effect of location, season and type of wheat on lead conc Nickel (Ni) The concentrations of Ni ranged from (5.655 7.698) mg/kg. The highest concentration of Ni was detected in wheat flour samples in Taji silo for spring season which value was 7.698 mg/kg, and local wheat sample in Taji silo for winter season 7.46 mg/kg. While, the lowest concentration of Ni was detected in the samples of local wheat and mixing mills in Al Rusafa silo for summer season which values were 5.655 mg/kg. And the highest level in AlDora silo for summer season was detected in local wheat 7.22mg/kg, and the lowest value was 5.81mg/kg in American wheat sample. In general, the concentration of Ni in all samples were below the maximum permissible level 67.90 mg/kg according to the FAO/WHO 2001 (11). This result shows in Figure 3. Statistical analysis revealed (appendix3) that was significant difference at probability (P≤0.05) among means in the Ni content across most samples of wheat grains and wheat flour analyzed, high significant difference was detected in Taji silo for spring season (2.381*), and within the same samples of mixing mills which was (2.804*).Moreover, the differences didn’t significant in the level of Ni occurrence in AlRusafa silo for spring season. Ni play some role in body activities including enzyme function in very trace amounts, it could be beneficial to activate some systems, but its toxic at higher level however, Ni toxicity in human is not a very common occurrence because its absorption by the body is very low, also Ni enhances the absorption of Zn. (22) these results complies with (17) which reported that wheat grain and flour values up to 6.2 mg/kg (Table 3). Iraqi Journal of Agricultural Sciences –2021:52(5):1139-1149 Mahdi & Omran 1143 Iron (Fe) From the results obtain as can reveal in Figure 4 the concentration of Fe in wheat grains and wheat flour samples ranged from (8.429108.95)mg/kg (Talbe 4) The maximum concentration of Fe was found in the samples of local wheat in Al Dora silo for summer and winter season which values were 108.95 mg/kg and 73.45 mg/kg respectively .while, the minimum concentrations of Iron was detected in the samples of wheat flour in AlRusafa silo for summer season and winter season for the same silo, the values were 8.429 mg/kg and 9.302 mg/kg respectively. The current data exhibited that the levels of Fe was found to be below the permissible limits in all the samples analyzed according to the FAO/WHO 2001 (11) which was detected maximum limits for Fe Concentration 425 mg/kg. Statistical analysis revealed (appendix4) significant differences at probability (P≤0.05) in the level of Iron content in all samples of wheat grains and wheat flour analyzed. Highest significant mean detected in Al Dora silo for summer season (13.66*), while within the same samples of local wheat in all silos and for all season which was (13.47*). Iron is an essential element in man and plays a vital role in the formation of hemoglobin, oxygen and electron transport in human body, various diseases of the digestive tract (chronic gastritis, enteritis) can also contribute to development of iron deficiency. Excess of iron in the organism is also harmful, it can cause siderosis of lungs and eyes, a disease that arises due to deposition of excess iron compounds in the tissues of those organs (16). These results were agreed with study conducted by Shobha and Kalshetty, 2017 which recorded the concentration of Fe in wheat was 39.9mg/kg(27), another local study in Iraq recorded a high level of Fe in local wheat which was (56.323+/-9.213) mg/kg (18). The variation in Fe concentration can be traced back to the application of several types of fertilization and that mineral nutrition greatly affected the concentration of Fe in the grains, also the bioavailability of Fe in flours are highly effected by the milling process (10). Zinc (Zn) From the Figure 5 shows the concentration of Zn in wheat grains and wheat flour samples ranged from (56.51-15.66) mg/kg, the highest concentration of Zn was detected in samples of local wheat and Canadian wheat in Al Dora silo for spring season which values were 56.51 mg/kg and 55.836 mg/kg respectively (Table 5). While, the lowest concentration of Zn was detected in sample of wheat flour in AlRusafa silo for winter season 15.66 mg/kg. The content of Zn found in these study was generally lower than the permissible levels set by FAO/WHO 2001 (11), the maximum limits of Zn in wheat grain was 99.4 mg/kg. Statistical analysis revealed (appendix5) among means significant differences at probability (P≤0.05) in levels of Iraqi Journal of Agricultural Sciences –2021:52(5):1139-1149 Mahdi & Omran 1144 Zn content in all samples of wheat grains and wheat flour analyzed. The highest significant was detected in Al Dora silo for spring season (8.55*), while within the same samples of mixing mills (8.61*). Zn is essential to all organisms and has an important role in metabolism, cellular growth and development. Zn is known to be a co-factor of many enzymes involved in metabolic pathway in the body .Zn deficiency lead to Coronary heart diseases and various metabolic disorders (24).The obtained result has Consistent and close agreement with the earlier reported by Gezahegn et al., 2017 which Zn content in wheat was (32.3 ± 2.7) mg/kg (13). Figure 5. The effect of location, season and type of wheat on Zinc conc Copper (Cu) the results show in Figure 6, concentration of Cu ranged from (3.67511.104) mg/kg (Table 6) The highest concentration of Cu was detected in local wheat samples in Taji silo for summer season and Al Dora silo for winter season which values were 11.104 mg/kg and 10.22 mg/kg respectively. While, the lowest concentration of Cu was detected in sample of wheat flour in Al Rusafa silo for spring season which value was 3.675 mg/kg. The level of Cu in all samples were observed to be lower than the permissible limit in wheat grains 73.30 mg/kg according to FAO/WHO 2001 (11). Statistical analysis revealed (appendi6) a significant differences at probability (P≤0.05) in levels of Cu content in all samples analyzed. Highest significant was detected in Al Dora silo for winter season (3.59*).moreover, within the same samples of local wheat was (3.29*). Copper is an essential trace element in plants and animals in the gut Copper is absorbed that facilitates iron uptake. RBC formation, its shortage can produced anemia-such symptoms, bone abnormalities, cholesterol metabolism, increased incidence of infections, abnormalities in glucose and neutropenia. However, excessive consumption may result in serious health problems like kidney and liver damage (14). The results of Cu are in agreement with Jamali et al., 2009 (17), and the level of copper in wheat was found to be a close agreement with Gezahegn et al., 2017 between (3.7 ± 0.5 mg/kg) to (5.5 ± 0.4 mg/kg)(13). Figure 6.The effect of location, season and type of wheat on Copper conc Chromium (Cr) The results in Figure 7 show the different concentrations of Cr ranged from (4.6860.513) mg/kg.(Table 7) The maximum concentration Cr was detected in the samples of wheat flour In Taji silo for spring season and in Australian wheat in Al Dora silo for spring season which values were 4.686 mg/kg and 4.413 mg/kg respectively, these values were above the permissible limits as 2.3 mg/kg set by FAO/WHO 2001 (11), while the lowest concentration of Cr was detected in most samples analyzed which valued 0.513 mg/kg. Statistical analysis revealed (Table 7) significant differences at probability (P≤0.05) in level of Cr content in Al Dora silo for spring season which value was (1.382*), in Taji silo for spring season LSD was (1.437*), in Iraqi Journal of Agricultural Sciences –2021:52(5):1139-1149 Mahdi & Omran 1145 AlRusafa silo for winter season was (0.544*).Moreover, within the same samples of wheat flour, Canadian wheat and Australian wheat were (1.226*, 0.639*.and 1.662*), respectively. While, in level of Cr occurrence in Al Dora silo for winter and summer seasons, Taji silo for winter and summer seasons and AlRusafa silo for spring and summer seasons, also within the same samples of local wheat, American wheat and mixing mills LSD value had no significant differences. These results obtained was a close agreement with study with study conducted by Gezahegn et al., 2017 in Addis Ababa reported Cr content in wheat grains as (2.5±0.2) mg/kg(13). Cr is important for effective insulin activity and DNA transcription (15). However, chronic exposure to Cr may have an effect on the liver (29).The observed variations in the concentration of Cr may be due to change of cereals variety, growing area, type of soil, climate, used fertilizer, water and agricultural practice.(13). Figure 7.The effect of location, season and type of wheat on Chromium conc Arsenic (As) From Figure 8 we can observe the different concentrations of As in all samples of wheat grains and wheat flour were the same concentration which was 0.265 mg /kg. In general, the As content in samples analyzed was below the maximum permissible safe limits in cereals 0.43 mg/kg according FAO/WHO 2001 (11). Statistical analysis revealed (Table 8) didn’t significant differences among means in levels of As content in all samples analyzed. As is extremely toxic and is thought to be carcinogenic for human. Long term exposure results in health effects like cardiovascular diseases and diabetes (1). The main source of AS to the environment is agrochemicals (pesticides) or volcanic eruption. Study conducted for distribution of As in wheat plant that the maximum level was found in Mardan 0.363 mg/kg, while the lowest level was observed in the Shergarh area 0.049 mg/kg (3).Another study AS content was found in a very low level and almost same in all studied cereals and wheat grain which was 0.2 mg/kg (13). Figure 8. The effect of location, season and type of wheat on Arsenic conc Cobalt (Co) From the results obtained in this study, as can be show from the Figure 9, the content of (Co) in all samples analyzed were the same concentration which was 3.067 mg/kg. The concentration of (Co) in all samples analyzed were below the maximum permissible safe limits in cereals 50 mg/kg according to the codex alimentarius commission ( Table 9) (11). Statistical analysis revealed (appendix9) significant differences in level of (Co) content in all samples analyzed except in Al Rusfa silo for spring season, within the same samples of wheat flour and local wheat which was no significant differences. Moreover, high significant differences was detected within the same samples of American wheat was (1.58*) and in Al Dora silo for spring season was (1.57*).A similar study for survey heavy metals in wheat grains conducted in India the Iraqi Journal of Agricultural Sciences –2021:52(5):1139-1149 Mahdi & Omran 1146 maximum concentration of Cobalt found in wheat 0.49 ppm and minimum value of Cobalt found 0.13 ppm in the same location. (27). Co is an important component of the vitamin B-12 molecule. It's required in the manufacture of RBC and in preventing anemia. Additionally, Vitamin B-12 prevents nerve damage by contributing to the formulation of the protective sheath that insulates nerve cells. An excess intake of cobalt may cause the overproduction of red blood cells (16). Figure 9.The effect of location, season and type of wheat on cobalt conc Table 1. Effect of Location, Season and Type of wheat sample on Cadmium concentration LSD value Type of wheat sample Season Location Wheat Flour Mixing Mills Canadian Wheat Australian Wheat American Wheat Local Wheat 1.39 * 1.4 1.8 0 1.6 1.6 1.4 Winter ecember 2018/12/19 Al Dora Silo 3.52 * 0.4 10.8 1.5 12.1 0 10.4 Spring March 2019 /3/27 Al Dora Silo 3.07 * 12.6 0 0 0 0 7.1 Summer May 2019 /5/19 Al Dora Silo 2.15 * 6.7 9.6 0 2.3 1.2 0.9 Winter December 2018/120/2 Taji Silo 2.33 * 8 3.4 0 1.3 2.6 1 Spring April 2019/4/3 Taji Silo 1.18 * 1.7 0.9 1.1 0 0 1 Summer June 2019/6/17 Taji Silo 1.79 * 1.5 5.2 0 8.1 6.1 2.3 Winter January 2019/1/17 AlRusfa Silo 2.05 * 1.5 1.9 1.3 7.6 0.8 2.8 Spring March 2019/3/26 AlRusfa Silo 1.72 * 1.6 1.1 3.3 0 0 0.5 Summer May 2019/5/7 AlRusfa Silo --2.87 * 2.68 * 1.55 * 2.82 * 1.93 * 2.48 * LSD value


INTRODUCTION
average cleanliness and aeration also. As for the mills belonging to the General Company for the manufacture of grain, the stores were fairly clean and the flour material was supplying after grinding immediately.For each sampling one kg. of wheat grain and flour were put into sterile polyethylene bags and seal properly, amount from each sample discrete and divided into two parts which preserved in a sterile plastic containers, to estimate the chemical properties (heavy metals). Samples were transported to the laboratory at 25°C until analysis were performed. X-ray fluorescence XRF is emerging as an appropriate method for speedy quantification owing to, the nondestructive nature of analysis heavy metals in vegetables and other foodstuff, as contemporary study revealed that lead and other heavy metals are absorbed and transported from the soil into consumable vegetable tissues (12). The principle of XRF is simple: when an X-ray emission from a radioactive source strikes a sample, the X-ray can be either absorbed by atoms or scattered through the material. The atoms after absorption becomes "excited" and release a characteristic X-ray which energy level is matchless to the element impacted by the incident X-ray, this characteristic X-ray emission is invited X-ray fluorescence, or XRF. The separate energy measurement of the X-ray emitted is used to determine the types of minerals present, and the measurement of the number of X-ray emitted supplies a quantitative indication of the concentration of the metal present in sample. That confirmed that each of the atomic elements it is found in a sample that produces a unique set of distinctive X-rays that are a fingerprint of the specified element (5). Preparation and sample analysis Wheat grain samples were collected from silos, 10g of each of them were oven dried at around 70°C, and left to cool at room temperature 25 °C. The dried mass of each sample was grounded to fine powder using grain miller (BraBenDer company, Germany origin), preserved in a sterile plastic container with identification mark label until analysis. Three grams prepared of the powder samples were weighed and pressed into pellets, the pellets were used for the determination of heavy metals such as(Hg , Pb ,Co, Cr, Fe, Cd, Ni, Ar ,Ag, Sn, Cu) levels were carried out using X-ray fluorescence spectrometry(Ametek company, Germany 2010 in origin) according to methods described previously (2) . Statistical analysis Statistical analysis (25) program was used to reveal the effect of differences agents on study parameters. LSD test (Least significant difference) was used for a significant difference for comparison between means. Correlation coefficient between traits was calculated.

RESULTS AND DISCUSSION Cadmium (Cd)
From the results obtained in this study, show in Figure1, the concentration value of cadmium in all samples analyzed of wheat grains and wheat flour ranged from (0.4-12.6) mg/kg=ppm. The highest concentration values detected in wheat flour and Australian wheat grain samples in Al Dora silo for summer and spring seasons which were 12.6 mg/kg and 12.1mg/kg respectively. While, the lowest concentration of Cd was detected in wheat flour samples and local wheat in Al Dora silo and AlRusafa silo for spring season and summer season respectively, the values were 0.4mg/kg and 0.5mg/kg respectively. These values of Cd in all samples analyzed were found to be above the permissible limits of 0.2mg/kg by FAO/WHO 2001 codex alimentarius commission(11).Statistical analysis revealed (Tabl11)that the means differed significantly at probability (P≤0.05) in the levels of Cd content in all samples analyzed of wheat grains and wheat flour in three silos for three seasons, high significant differed was observed in Al Dora silo for spring season which was (3.52*) and within the same sample of wheat flour LSD value was (2.87*). Cd is highly toxic non-essential elements and it does not have role in the biological process in living organisms, even lower concentration of Cd in the food chain could be harmful to living organisms (15).Furthermore, these results were agreed with study conducted by Chandra et al., 2009 found Cd content was1.06 mg/kg in wheat grains with soil irrigated with industrial wastewater (6). In previous studies found that application of sewage sludge to fields can an alternative to manure addition which lead to accumulation of cd in cereals. Moreover, Cadmium content of wheat grain or flour is influenced by several factors such as annual variation, cultivar differences, genetically and regional variations. Regional differences found in cadmium level are mainly affected by cadmium deposition via the atmosphere, soil fertilization and soil properties such as soil type, pH, origin and soil cadmium content .Also soil salinity enhances Cd uptake of many crops(9).  Figure  2. the maximum concentration of pb was detected in Al Dora silo in local wheat for winter and summer seasons and wheat flour for spring season which value was 1.021 mg/kg, furthermore the same value was detected in local wheat for winter season, in Australian wheat for spring season in Taji silo and mixing mills in Al Rusafa silo for summer season.
While, the minimum level concentration of pb was detected in the local wheat sample in Taji silo for spring season which value was0.092 mg/kg. These values of pb in most samples analyzed were found to be above the permissible limits of 0.2mg/kg by (FAO/WHO) Codex alimentarius commission(11), except in Taji silo was detected in wheat flour sample for winter season 0.185 mg/kg, local wheat 0.092 mg/kg for spring season, mixing Mills for summer season 0.185 mg/kg, also in Al Rusafa silo sample of wheat flour 0.186 mg/kg for winter season, finally in local wheat 0.185 mg/kg for summer season. That ingestion of lead is harmful at both high and low levels especially for the most sensitive populations (fetuses and young children). Chronic exposure to lead may cause birth defects, mental retardation, psychosis, hyperactivity, shaky hands, muscular weakness, paralysis (beginning in the forearms) and even death (26). Statistical analysis revealed (appendix2)that the means differed significantly at probability (P≤0.05) in the level of pb content in most samples of wheat grains and wheat flour analyzed, highest significant differences were detected in Al Dora silo for winter season (0.883*) and within the same samples of mixing mills were (0.723*).While, that the means didn't differed significantly in the levels of pb contents were observed in Taji silo for summer season, and AlRusafa silo for both winter and spring seasons. These results agreed with previous study was conducted in A ( Table 2)dis Ababa which reported that pb level content in wheat grains was 1.02 mg/kg, while high value of pb content was detected in barley which was 2.23 mg/kg (13).These results were in disagreement with the study conducted by Shobha and Kalshetty, 2017 in India (27), which pb content ranged from (0.08-0.163) mg/kg. The main factor that affects the high content of lead in grain is absorption through air pollution as a result of the pollution from the highway traffics which can affect the irrigation water or farm soil of the plants, and related to the milling plates in both dry and wet conditions (8).   Figure 3. Statistical analysis revealed (appendix3) that was significant difference at probability (P≤0.05) among means in the Ni content across most samples of wheat grains and wheat flour analyzed, high significant difference was detected in Taji silo for spring season (2.381*), and within the same samples of mixing mills which was (2.804*).Moreover, the differences didn't significant in the level of Ni occurrence in AlRusafa silo for spring season. Ni play some role in body activities including enzyme function in very trace amounts, it could be beneficial to activate some systems, but its toxic at higher level however, Ni toxicity in human is not a very common occurrence because its absorption by the body is very low, also Ni enhances the absorption of Zn. (22) these results complies with (17) which reported that wheat grain and flour values up to 6.2 mg/kg (Table 3).

Iron (Fe)
From the results obtain as can reveal in Figure  4 the concentration of Fe in wheat grains and wheat flour samples ranged from ( significant differences at probability (P≤0.05) in the level of Iron content in all samples of wheat grains and wheat flour analyzed. Highest significant mean detected in Al Dora silo for summer season (13.66*), while within the same samples of local wheat in all silos and for all season which was (13.47*). Iron is an essential element in man and plays a vital role in the formation of hemoglobin, oxygen and electron transport in human body, various diseases of the digestive tract (chronic gastritis, enteritis) can also contribute to development of iron deficiency. Excess of iron in the organism is also harmful, it can cause siderosis of lungs and eyes, a disease that arises due to deposition of excess iron compounds in the tissues of those organs (16). These results were agreed with study conducted by Shobha and Kalshetty, 2017 which recorded the concentration of Fe in wheat was 39.9mg/kg (27), another local study in Iraq recorded a high level of Fe in local wheat which was (56.323+/-9.213) mg/kg (18). The variation in Fe concentration can be traced back to the application of several types of fertilization and that mineral nutrition greatly affected the concentration of Fe in the grains, also the bioavailability of Fe in flours are highly effected by the milling process (10). Figure 5 shows the concentration of Zn in wheat grains and wheat flour samples ranged from (56.51-15.66) mg/kg, the highest concentration of Zn was detected in samples of local wheat and Canadian wheat in Al Dora silo for spring season which values were 56.51 mg/kg and 55.836 mg/kg respectively (Table 5). While, the lowest concentration of Zn was detected in sample of wheat flour in AlRusafa silo for winter season 15.66 mg/kg. The content of Zn found in these study was generally lower than the permissible levels set by FAO/WHO 2001 (11), the maximum limits of Zn in wheat grain was 99.4 mg/kg. Statistical analysis revealed (appendix5) among means significant differences at probability (P≤0.05) in levels of Zn content in all samples of wheat grains and wheat flour analyzed. The highest significant was detected in Al Dora silo for spring season (8.55*), while within the same samples of mixing mills (8.61*). Zn is essential to all organisms and has an important role in metabolism, cellular growth and development. Zn is known to be a co-factor of many enzymes involved in metabolic pathway in the body .Zn deficiency lead to Coronary heart diseases and various metabolic disorders (24).The obtained result has Consistent and close agreement with the earlier reported by Gezahegn et al., 2017 which Zn content in wheat was (32.3 ± 2.7) mg/kg (13).  Figure 6, concentration of Cu ranged from (3.675-11.104) mg/kg (Table 6) The highest concentration of Cu was detected in local wheat samples in Taji silo for summer season and Al Dora silo for winter season which values were 11.104 mg/kg and 10.22 mg/kg respectively. While, the lowest concentration of Cu was detected in sample of wheat flour in Al Rusafa silo for spring season which value was 3.675 mg/kg. The level of Cu in all samples were observed to be lower than the permissible limit in wheat grains 73.30 mg/kg according to FAO/WHO 2001 (11). Statistical analysis revealed (appendi6) a significant differences at probability (P≤0.05) in levels of Cu content in all samples analyzed. Highest significant was detected in Al Dora silo for winter season (3.59*).moreover, within the same samples of local wheat was (3.29*). Copper is an essential trace element in plants and animals in the gut Copper is absorbed that facilitates iron uptake. RBC formation, its shortage can produced anemia-such symptoms, bone abnormalities, cholesterol metabolism, increased incidence of infections, abnormalities in glucose and neutropenia. However, excessive consumption may result in serious health problems like kidney and liver damage (14). The results of Cu are in agreement with Jamali et al., 2009 (17), and the level of copper in wheat was found to be a close agreement with Gezahegn et al., 2017 between (3.7 ± 0.5 mg/kg) to (5.5 ± 0.4 mg/kg)(13).

Figure 6.The effect of location, season and type of wheat on Copper conc Chromium (Cr)
The results in Figure 7 show the different concentrations of Cr ranged from (4.686-0.513) mg/kg. (Table 7) The maximum concentration Cr was detected in the samples of wheat flour In Taji silo for spring season and in Australian wheat in Al Dora silo for spring season which values were 4.686 mg/kg and 4.413 mg/kg respectively, these values were above the permissible limits as 2.3 mg/kg set by FAO/WHO 2001 (11), while the lowest concentration of Cr was detected in most samples analyzed which valued 0.513 mg/kg. Statistical analysis revealed (Table 7) significant differences at probability (P≤0.05) in level of Cr content in Al Dora silo for spring season which value was (1.382*), in Taji silo for spring season LSD was (1.437*), in AlRusafa silo for winter season was (0.544*).Moreover, within the same samples of wheat flour, Canadian wheat and Australian wheat were (1.226*, 0.639*.and 1.662*), respectively. While, in level of Cr occurrence in Al Dora silo for winter and summer seasons, Taji silo for winter and summer seasons and AlRusafa silo for spring and summer seasons, also within the same samples of local wheat, American wheat and mixing mills LSD value had no significant differences. These results obtained was a close agreement with study with study conducted by Gezahegn et al., 2017 in Addis Ababa reported Cr content in wheat grains as (2.5±0.2) mg/kg (13). Cr is important for effective insulin activity and DNA transcription (15). However, chronic exposure to Cr may have an effect on the liver (29).The observed variations in the concentration of Cr may be due to change of cereals variety, growing area, type of soil, climate, used fertilizer, water and agricultural practice. (13).  (Table 8) didn't significant differences among means in levels of As content in all samples analyzed. As is extremely toxic and is thought to be carcinogenic for human. Long term exposure results in health effects like cardiovascular diseases and diabetes (1). The main source of AS to the environment is agrochemicals (pesticides) or volcanic eruption. Study conducted for distribution of As in wheat plant that the maximum level was found in Mardan 0.363 mg/kg, while the lowest level was observed in the Shergarh area 0.049 mg/kg (3).Another study AS content was found in a very low level and almost same in all studied cereals and wheat grain which was 0.2 mg/kg (13).

Figure 8. The effect of location, season and type of wheat on Arsenic conc Cobalt (Co)
From the results obtained in this study, as can be show from the Figure 9, the content of (Co) in all samples analyzed were the same concentration which was 3.067 mg/kg. The concentration of (Co) in all samples analyzed were below the maximum permissible safe limits in cereals 50 mg/kg according to the codex alimentarius commission ( Table 9) (11). Statistical analysis revealed (appendix9) significant differences in level of (Co) content in all samples analyzed except in Al Rusfa silo for spring season, within the same samples of wheat flour and local wheat which was no significant differences. Moreover, high significant differences was detected within the same samples of American wheat was (1.58*) and in Al Dora silo for spring season was (1.57*).A similar study for survey heavy metals in wheat grains conducted in India the maximum concentration of Cobalt found in wheat 0.49 ppm and minimum value of Cobalt found 0.13 ppm in the same location. (27). Co is an important component of the vitamin B-12 molecule. It's required in the manufacture of RBC and in preventing anemia. Additionally, Vitamin B-12 prevents nerve damage by contributing to the formulation of the protective sheath that insulates nerve cells. An excess intake of cobalt may cause the overproduction of red blood cells (16).