Proceedings of the 4 th Environmental Physics Conference, 10-14 March 2010, ,

THE ANNUAL DOSE FOR POPULATION DUE TO CONSUME THE ANIMAL PRODUCTS

S. Harb, K. Salahel Din, A. Abbady and Nagwa Saad

Physics Dept., Faculty of Science, , 83523, Qena, Egypt

Several kinds of cattle and poultry fodder samples collected from South Valley University and Qena governorate farm, Qena, were estimated for their natural radioactivity concentrations due to Ra226, Ra228, Th232 and K40 radionuclides. Twenty nine samples were analyzed by using lowlevel gamma spectrometric. Based on radionuclides concentrations in animal fodder and annual consumption rate, the human health risk from irradiation due to indirect ingestion can be assessed. The annual effective dose from these radionuclides, which may reach the local consumer through beef, milk, poultry and eggs consumption have been estimated as 2.7E+00, 1.4E+01, 1.0E01 and 1.4E01 Sv/y, respectively.

Keyword s: Radioactivity , Natural radionuclides, Gamma spectrometric, Animal and poultry feed , Annual effective dose

1. INTRODUCTION

Radiation from natural sources gives more than 80 % of the total exposure received by the average member of a population and a portion of this exposure comes from dietary intake [1]. The natural radioactivity elements are distributed everywhere in the environmental with different concentrations, their concentrations have been found to depend on the local geological condition and as such they vary from one place to another. It is necessary to monitor release of radioactivity into the environment in order to be able to provide an appropriate protection of humans [2]. Radionuclides in soil are taken up by plants, thereby becoming available for further redistribution within food chains these plants may be involved directly in human food or indirectly such as animal fodder [3]. Over the years much work on radioactive food contamination in the environment and its transfer or pathway mechanism to plants, animals and human population has been reported [4, 5]. Ingestion of natural radionuclides depends on the consumption rates of food and water and on the radionuclide concentrations. The supply of meat in Egypt comes from four major sources. These are cattle, poultry, goat meat and mutton. Cattle contribute the highest percentage of 44.54 % and poultry takes second place with 36.86 % while mutton contributes (sheep and goat) 3.8 % each [6]. The aim of this study is to calculate the doses received by population in Qena governorate owing to consume products from south valley university farm and

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Proceedings of the 4 th Environmental Physics Conference, 10-14 March 2010, Hurghada, Egypt governorate farm. In order to accomplish this objective we measured the activity concentration levels due to naturally occurring radionuclides in animal's food and then using theoretical calculation to calculate the annual doses received by population in Qena governorate due to consume the animal products.

2 MATERIALS AND METHODS

The animal and poultry fodder samples were collected from South Valley University (S.V.U.) and Qena Governorate (Q.G.) farms on Qena road in Qena governorate figure 1. Fodder samples for each location were dried in air to obtain a constant dry weight. The samples were powdered and then transferred into cylindrical plastic containers. These samples were sealed and left for a period of one month to allow Ra and its shortlived progenies to reach secular radioactive equilibrium. Specific activity of each radionuclide was calculated using the following equation [7]:

As = C n / ( ε P γ M s) (1) where, A s is the specific activity of each radionuclide in sample (Bq/kg), Cn is count per second, ε is the detector efficiency, Pγ is the emission probability, and M s is sample weight (kg).

Figure 1. Qena governorate map.

Each sample was measured with a NaI (Tl) detector, although the NaI (Tl) gammaray spectrometer has poor energy resolution but its high efficiency allows fast and precise determinations of Ra226, Ra228, Th232 and K40 concentrations in samples. The results depend on the accuracy of the energy calibration procedure that takes into account the possible interference of each nuclide in each peak region. In order to minimize the background radiation, the detection system and the sample container were placed inside a shield, composed by lead layer, with thickness of 5 cm.

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Proceedings of the 4 th Environmental Physics Conference, 10-14 March 2010, Hurghada, Egypt

Every sample was counted for 10 to 15 h depending on the level of concentrations of the radionuclides. System was calibrated for efficiency using a mixed ten radionuclides gamma standard QCY48 (obtained from Physikalisch Technische Bundesanstalt PTB, Germany) [8], before the sample was placed in detection system. Prior to sampling counting, background were normally taken every week under the same condition of sample measurement and then subtracted from the samples counted during that week. The spectra were evaluated with the computer software program Maestro (EG&GORTIC). Figure 2 show gamma lines which are measured by NaI. The Ra226 concentration was determined from the gamma lines of 352 keV and 609 keV from Pb 214 and Bi214. Ra226 concentration was calculated as the mean value of the results of these gamma lines. The Th232 concentration was determined from the gamma lines of 238 keV, 911 keV from Pb212 and Ac228, respectively and Ra228 was determined from the gamma line 911 KeV from Ac228. K40 was determined from its gamma lines of 1460 keV.

10000

Pb212 214 - Pb-214 Bi Bi-214 Ac228

K-40 Bi214

1000 Tl208

100

Log Count

10

1 0 500 1000 1500 2000 2500 3000 Energy (Kev)

Figure 2. The gamma spectra of radionuclides from fodder samples (Rs).

3 RESULTS AND DISCUSSION

Table 1 presents the result of the specific activities of R226, Ra228, Th232 and K40 in the different samples under investigations.

Cattle fodder The average value of Ra226, Ra228, Th232 and K40 concentration in South Valley University farm fodder were 0.30 ± 0.01, 0.31± 0.02, 0.28 ± 0.02 and 83.52 ± 2.99 Bq/Kg, respectively, in Fodder mixture, while in grass fodder (Silage and Rice straw)

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Proceedings of the 4 th Environmental Physics Conference, 10-14 March 2010, Hurghada, Egypt

they ranged from 3.58 ± 0.17 to 4.31 ± 0.17, 2.63 ± 0.15 to 5.33 ± 0.23, 1.99 ± 0.13 to 2.51 ± 0.14 and 282.72 ± 10.13 to 397.12 ± 14.15 Bq/Kg, respectively. The mean values of these radionuclides in Qena Governorate farm fodder mixture were 1.62 ± 0.06, 1.85 ± 0.07, 0.23 ± 0.04 and 195.26 ± 6.36 Bq/Kg, respectively, while in grass fodder (Hay and Rice straw), they were 3.20 ± 0.15, 3.31 ± 0.22, 2.36 ± 0.17 and 377.02 ± 13.33 Bq/kg, respectively. The results showed that the average values of Qena Governorate farm were higher than South Valley University farm values. Table 1. Ra226, Ra228, Th232 and K40 activity concentrations (Bq/kg) in fodder samples from two farms. Activity concentration (Bq/Kg) (dry weight) Samples

Farm Farm Ra226 Ra228 Th232 K40

Type feed Type feed Fodder mixture (FM) 0.30 ± 0.01 0.31 ± 0.02 0.28 ± 0.02 83.52 ± 2.99 Silage (Zea mays) (Sz) 3.58 ± 0.17 3.16 ± 0.18 1.99 ± 0.13 282.72 ± 10.13 Silage (Sorghum) (Ss) 4.31 ± 0.17 5.33 ± 0.23 2.17± 0.15 363.08 ± 12.31

Cattle’s food Cattle’s food Rice straw (Rs) 3.91 ± 0.17 2.63 ± 0.15 2.51± 0.14 397.12 ± 14.15 Poultry feed 1 (PF1) 0.35 ± 0.02 0.95 ± 0.05 0.27 ± 0.03 62.98 ± 2.25 S.V.U. farm S.V.U. farm

food Poultry feed 2 (PF2) 0.38 ±0.02 0.49 ± 0.03 0.33 ± 0.02 60.51 ± 2.13 Poultry’s

Fodder mixture (FM) 1.62±0.06 1.85±0.07 0.23±0.04 195.26±6.36 Hay (H) 2.46±0.11 2.82±0.24 1.87±0.17 292.95±10.51 food Cattle’s Rice straw (Rs) 3.93±0.19 3.79±0.20 2.85±0.16 461.09±16.15

Q.G. farm farm Q.G. Poultry feed 1 (PF1) 1.12±0.06 1.33±0.05 0.84±0.04 80.87±2.87

s foods 1.17±0.04 1.58±0.08 1.07±0.06 91.21±3.19

Poultry’ Poultry feed 2 (PF2)

Poultry fodder In South Valley University farm, the mean values of Ra226, Ra228, Th232 and K40 activity concentrations were 0.35±0.02, 0.95±0.05, 0.27±0.03 and 62.98 ±2.25 Bq/kg, respectively for (Pf1), whereas corresponding values in (Pf2) were 0.38±0.02, 0.49±0.03, 0.33±0.02 and 60.51±2.13 Bq/kg. Whereas the mean values of these radionuclides in Qena Governorate farm are 1.12±0.06, 1.33±0.05, 0.84±0.04 and 80.87±2.87 (Bq/kg), respectively in Poultry feed1 and in Poultry feed2 are 1.17±0.04, 1.58±0.08, 1.07±0.06 and 91.21±3.19 (Bq/kg), respectively. From results the average values of these radionuclides in poultry fodder from Qena Governorate farm were higher than South Valley University farm values.

Annual Dose from Animal Products . The annual effective dose for humans ingesting farm products could be calculated using the equation [5, 9]: D = C ×U × D (1) i i i

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Proceedings of the 4 th Environmental Physics Conference, 10-14 March 2010, Hurghada, Egypt

Where D i the annual effective dose, U i is the annual consumption rate of farm products (kg/y), D is the dose conversion factor for ingestion of radionuclide (Sv/Bq). C i is the concentration of radionuclide in farm products (beef, milk, poultry and eggs) (Bq/kg) and it was calculated using the equation [5, 10]: C = C ×Q × F (2) i j j i

Where C i is predicted concentration in farm products (beef, milk, poultry and eggs) (Bq/kg) at time of consumption, C j is the mean concentration of radionuclides in fodder, Q j is the amount of fodder consumed by cattle or poultry each day (kg/d) and F i is the average fraction of the animal’s daily intake of radionuclide that appears in each kg of product [11]. The used D values for our computation are listed in UNSECR 2000 [12] and the annual consumption rate of products in Egypt is considered applied from food balance sheet 2006 [13]. Based on the activity concentrations of fodder, listed in table 1, the activity concentration of Ra226, Ra228, Th232 and K40 in farm products from two farms were calculated using Eq.2 and the obtained values are shown in Table 2. From table 2 we can notice that • The highest value of Ra226 and Ra228 were recorded in milk of both of two farms that is may be attributed to Ra solubility in water is high in addition to daily intake of Ra226 and Ra228 by milk cattle is high. • The highest value of K40 was recorded in beef. Table 2. The concentration of Ra226, Ra228, Th232 and K40 (Bq/Kg) in two farms products. Products Activity concentration (Bq/Kg) Farm Ra226 Ra228 Th232 K40 beef 1.8E02 1.6E02 5.0E04 4.4E+01 S.V.U milk 3.3E02 2.7E02 8.1E05 2.0E+01 poultry 8.8E04 1.1E03 1.5E04 1.9E+00 egg 1.3E03 3.6E03 1.3E04 7.9E+00 beef 1.63E02 1.78E02 2.94E04 4.33E+01 Q.G. milk 3.24E02 3.52E02 5.59E05 2.14E+01 poultry 2.70E03 3.6E03 4.94E04 2.81E+00 egg 4.21E03 5.0E03 4.18E04 1.01E+01 • The activity concentration of natural radionuclides under investigation in poultry and egg from Qena governorate farm are higher than the activity concentration of these radionuclides in poultry and egg from South Valley University farm. That is because the activity concentration of those radionuclides in poultry fodder of Qena governorate farm was the high. • The activity concentration of Th232 in milk and beef from South Valley University farm is higher than the activity concentration of these radionuclides in milk and beef from Qena governorate farm. That is attributed to the activity concentration of those radionuclides in cattle fodder of South Valley University farm was the high.

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Proceedings of the 4 th Environmental Physics Conference, 10-14 March 2010, Hurghada, Egypt

• The value of Ra226, Ra228 and K40 in milk and beef from two farms are approximately similar, that was due to the daily intake of Ra226, Ra 228, Th232 and K40 by cattle in two farms is approximately similar. Table 3 summarized the values of Ra226, Ra228, Th232 and K40 concentrations in some countries compared with the present wok. From the table (3) it can be seen that in milk, Ra226 activity concentrations obtained in present work is higher than that reported by M.S. Choi et al (2008) [16] in Korean, but the mean values of Ra228 and K40 are higher than that reported by M.S. Choi et al (2008) [16] in Korean. While the mean values of Ra226, Ra228, Th232 and K40 in beef and poultry in present work are lower than that reported by M.S. Choi et al (2008) [16] in Korean.

Table 3. Values of Ra226, Ra228, Th232 and K40 (Bq/Kg) for all product samples under investigation beside other countries. type of Activity concentration (Bq/Kg) Country Ref. product Ra226 Ra228 Th232 K40 Egypt present 3.3E02 2.7E02 0.08E03 2.0E+01 (S.V.U. farm) work Egypt (Q.G. 2.14E+01 present 3.24E02 3.52E02 0.06E03 farm) work milk 5.0 E+017.5 [14] Argentinean E+01 Syria 5.40E+01 [15] Korean 2.2E02 4.1E02 0.08E03 5.29E+01 [16] United States 0.57 E02 0.27 E03 [12] Egypt present 1.8E02 1.6E02 0.50E03 4.4E+01 (S.V.U. farm) work Egypt (Q.G. present 1.63E02 1.78E02 0.29E03 4.33E+01 farm) work beef 0.3E03 [12] United States 2.0E02 2E03 China 4.1E02 12E02 4.30E03 [12] Nigeria 2.4E+00 2.66E+02 [17] Korean 3.6E02 2.1E02 1.45E03 9.01E+01 [16] Egypt present 0.09E02 0.11E02 0.15E03 1.9E+00 (S.V.U. farm) work poultry Egypt (Q.G. present 0.27E02 0.36E02 0.49E03 2.81E+00 farm) work Korean 2.6E02 2.4E02 1.27E03 5.85E+01 [16]

By using the values in table 2 and applying Eq. 1, the annual effective dose from Ra226, Ra228, Th232 and K40 that may be incurred through farm product consumption have been estimated and shown in table 4. From Table 4, the annual effective doses due to the ingestion of Ra226, Ra228, Th 232 and K40 in milk are higher than the other farm products (1.44E+01 and 1.35E+01Sv/y in Q.G. and S.V.U. farm, respectively). Also from the table 4 we can see that the lowest value of annual effective dose in poultry (1.25E01 and 0.76E 01Sv/y). The annual effective dose from South Valley University farm products (milk

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Proceedings of the 4 th Environmental Physics Conference, 10-14 March 2010, Hurghada, Egypt

and beef) ingestion was approximately similar with the value from Qena Governorate farm products (milk and beef) ingestion. This is because of activity concentration of Ra226, Ra228 and K40 in cattle products from two farms is approximately similar. Whereas annual effective dose from Qena Governorate farm products (poultry and eggs) ingestion was high.

Table 4. The annual effective dose (Sv/y) from Ra226, Ra228, Th232 and K40 from two farms products consumption. Annual effective dose (Sv/y) Farm products Ra226 Ra228 Th232 K40 total beef 4.7E02 1.0E01 1.1E03 2.6E+00 2.70E+00 milk 80.7E02 1.6E+00 1.6E03 1.1E+01 1.35E+01 poultry 0.15E02 4.7E03 2.1E04 6.9E02 7.57E02

S.V.U egg 0.09E02 5.9E03 7.4E05 1.2E01 1.24E01 beef 4.2E02 1.1E01 6.3E04 2.5E+00 2.65E+00 milk 78.7E02 2.1E+00 1.1E03 1.2E+01 1.44E+01 poultry 0.45E02 1.5E02 6.8E04 1.0E01 1.25E01

Q.G. egg 0.28E02 0.83E02 2.3E04 1.5E01 1.62E01

From Figure 3 we can notice that high dose contributor is caused by K40 for local consumer, while Ra228 ranks the second contributor to the dose. The most important contributed of dose is Ra228 where its metabolic behavior in the body is similar to that of calcium [18] while K40 concentration in the body is under homeostatic control [12]. Ra226 1.75% Ra228 Ra226 Ra228 3.77% Th232 5.99% 0.04% 12.19% K40 Th232 81.81% 0.01%

K40 94.44% Beef Milk

Ra226 Ra228 Ra226 Ra228 Th232 0.71% 4.76% 1.95% 6.19% Th232 0.06% 0.28%

K40 K40 94.47% 91.58% Poultry Eggs

Figure 3a. The relative contributions to annual effective dose due to S.V.U. farm products consumption owing to Ra226, Ra228, Th232 and K40. 43

Proceedings of the 4 th Environmental Physics Conference, 10-14 March 2010, Hurghada, Egypt

Ra226 Ra226 Ra228 5.46% Ra228 1.60% 4.32% Th232 14.63% 0.02% Th232 0.01%

K40 K40 79.90% 94.06% Beef Milk

Ra228 Ra228 Ra226 Ra226 5.11% 12.10% Th232 3.64% 1.75% 0.14% Th232 0.55%

K40 K40 83.71% 93.00% Poultry Eggs

Figure 3b. The relative contributions to annual effective dose due to Q.G. farm products consumption owing to Ra226, Ra228, Th232 and K40.

4. CONCLUSION

The estimated annual effective dose from cattle products ingestion from two farms was approximately small. This is because of daily intake of Ra226, Ra228, Th 232 and K40 by cattle in two farms is approximately similar. Whereas annual effective dose from Qena Governorate farm products (poultry and eggs) ingestion was higher than that of South Valley University. The estimated annual effective dose rates to local consumers in Qena governorate are lower than those predicted by UNSCEAR2000 [12].

5. REFERENCE

[1] Carter, M.W., Radionuclides in the Food Chain, New York: SpringerVerlag , 1988, pp. 58 71. [2] Yaxin Yang, Xinmin Wu, Zhongying Jianga, WeixingWang, Jigen Lua, Jun Lina, Lei MingWang and Yuanfu Hsia.. Applied Radiation and Isotopes 63, 255259 (2005). [3] Ciuffo, L.E.C., Belli, M., Pasquale, A., Menegon, S. and Velasco, H. R., The Science of the Total Environment 295, 6980 (2002). [4] Gaso, M.I., Segovia, N., Cervantes, M.L., Herrera, T., and PrerezSilva, E., Radiation Protection Dosimetry 87, 213216 (2000). [5] Jibiri, N.N. and Ajao, A.O., Journal of Environmental Radioactivity 78, 105111 (2005).

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Proceedings of the 4 th Environmental Physics Conference, 10-14 March 2010, Hurghada, Egypt

[6] FAO statistics (Food and agriculture organization of united nations, FAOSTAT 2004, http://faostat.fao.org. [7] International Atomic Energy Agency, Measurement of radionuclides in food and the environment. Guide book. Technical report series No 295, IAEA, Viennia (1989). [8] PTB, (Certified of multinuclear QCY48), Physikalisch Technische Bundesanstalt PTB, Germany (2007). [9] Lentzner, L. Howard, Siemering, S. Geoff and Rath, S. Karen, LLNL Environmental Report (1998), Appendix A: (author: S. Ring Peterson). [10] Till, J.E., Moore, R.E., Health Physics 55, 541–548 (1988). [11] Staven, L.H., Rhoads, K., Napier, B.A. and Strenge, D.L., A Compendium of Transfer Factors for Agricultural and Animal Products, Washington: Pacific Northwest National Laboratory Richland, operated for the United States Department of Energy (2003). [12] UNSCEAR, 2000. United Nations Scientific Committee on the effects of Atomic Radiation, United Nations, New York, p 9396, p124127. [13] Food balance sheet, Ministry of Agriculture and Land Reclamation, Economic Affairs Sector, Egypt (in language), pp. 22 23 (2006). [14] Desimoni, J., Sives, F., Errico, L., Mastrantonio, G., Taylor, M.A., Journal of Food Composition and Analysis 22, 250253 (2009). [15] AlMasri, M.S., Mukallati, H., AlHamwi, A., Khalili, H., Hassan, M., Assaf, H., Amin, Y., Nashawati, A., Journal of Radioanalytical and Nuclear Chemistry, 260, 405412 (2004). [16] Choi, MinSeok, Lin, XiuJing, Lee, Sun Ah, Kim, Wan, Kang, HeeDong, Doh, SihHong, Kim, DoSung and Lee, DongMyung, Journal of Environmental Radioactivity 99, 1319–1323 (2008). [17] Akinloye, M.K., Olomo, J.B., Olubunmi, P.A., Nuclear Instruments and Methods in Physics Research A 422, 795800 (1999). [18] Wrenn, M.E., Durbin, P. W., Howard, B., Lipsztein, J., Rundo, J., Still, E.T., and Willis, D.I., Health Physics, 48, 601633 (1985).

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