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Asian Journal of Research and Reviews in Physics
3(1): 8-16, 2020; Article no.AJR2P.53523
Evaluation of Radiation Hazard Indices in Mining
Sites of Nasarawa State, Nigeria
U. Rilwan
1*
, I. Umar
2
, G. C. Onuchukwu
3
, H. A. Abdullahi
4
and M. Umar
1
1
Department of Physics, Nigerian Army University, P.M.B 1500, Biu, Borno State, Nigeria.
2
Department of Physics, Nasarawa State University, P.M.B 1022, Keffi, Nasarawa State, Nigeria.
3
Vice Chancellor’s Office, Nigerian Army University, P.M.B 1500, Biu, Borno State, Nigeria.
4
National Agency for Science and Engineering Infrastructure, IduIndustrial Area, P.M.B 391, Garki,
Abuja, Nigeria.
Authors’ contributions
This work was carried out in collaboration among all authors. Author UR designed the study,
performed the statistical analysis, wrote the protocol and wrote the first draft of the manuscript.
Authors UR, IU and GCO managed the analyses of the study. Authors UR, HAA and MU managed
the literature searches. All authors read and approved the final manuscript.
Article Information
Editor(s):
(1)
Prof. Shi-Hai Dong, Department of Physics, School of Physics and Mathematics, National Polytechnic Institute, Building 9,
Unit Professional Adolfo Lopez Mateos, A. P. 07738, Mexico D. F., Mexico.
(2)
Dr. Jelena Purenovic, Assistant Professor, Department of Physics and Materials, Faculty of Technical Sciences,
Kragujevac University, Cacak, Serbia.
Reviewers:
(1) Wiseman Bekelesi, Hiroshima University, Japan.
(2)
Abiola Olawale Ilori, University of KwaZulu-Natal, South Africa.
(3)
Branko Vuković, University of Osijek, Croatia.
Complete Peer review History:
http://www.sdiarticle4.com/review-history/53523
Received 15 November 2019
Accepted 20 January 2020
Published 23 January 2020
ABSTRACT
This work evaluates the radiation hazard indices from some selected mining sites in Nasarawa
West, using Sodium Iodide Thallium Gamma Spectrometry. Ra
eq
ranged from 100.39-197.40 Bq/Kg
with a mean 161.44 Bq/Kg, which is lower than the average of 370 Bq/Kg. The GADR ranged from
44.85 nGy/hr-90.71 nGy/hr with the mean 73.68 nGy/hr. which is also below the average of 89
nGy/hr for soil. The AGED ranged from 315.77 mSv/yr-640.91 mSv/yr with the mean 519.19. Which
is above the threshold value of 300 mSv/yr. ACI ranged from 0.73-1.45 with the mean value 1.18
which is above the standard of unity. The AEDE (outdoor) ranges from 0.055 mSv/yr-0.111 mSv/yr
with the mean 0.090 mSv/yr which is above the 0.07 mSv/yr standard permissible limit. The AEDE
(indoor) ranged from 0.220 mSv/yr-0.445 mSv/yr, with the mean value 0.361mSv/yr. This is below
the 0.45 mSv/yr threshold. The ELCR ranged from 00.770-1.558 with the mean value 1.265 and
Original Research Article
Rilwan et al.;
AJR2P, 3(1): 8-16, 2020; Article no.AJR2P.53523
9
from 0.193-0.389 with the mean value 0.317 for outdoor and indoor respectively, which exceed the
0.29 X 10
-3
threshold limit. The External and Internal Hazard indices ranges from 0.271-0.533
and 0.289-0.675 as well as mean values 0.435 and 0.512 respectively, which are below the
threshold. Therefore, there may be serious radiological effects to the populace.
Keywords: Radionuclide; radiation; hazard indices; Nasarawa State.
1. INTRODUCTION
The assessment of radioactivity in our
environment allows the determination of
population radiation exposure. The occurrence of
radionuclides in soil depends on the soil
formation as well human activities in the area,
such as the geology of the area, tin mining and
use of fertilizers in agriculture [1,2]. Consumption
of ground water with elevated amounts of natural
radionuclides may increase the radioloxicity to
human and internal exposure [3] to radiation
caused by the decay of the natural radionuclides
taken into the body through ingestion as well as
inhalation. The decay process leads to the
release of several alpha and beta particles which
are responsible for the total radiation dose
received from natural radioactivity as well as
artificial [4,5]. The aim of this study was to
Evaluation of Radiation Hazard Indices in Mining
Sites of Nasarawa State. Nigeria.
2. MATERIALS AND METHODS
2.1 Materials
In the course of the radiometric study, the
following items or materials were used as shown
in Table 1.
2.2 Study Area
Four villages were chosen in Nasarawa LGA.
The villages are Eyenu, OPanda, Okereku and
Udegen-Mbeki abbreviated as NW1, NW2, NW3
and NW4 respectively. The villages NW1, NW2,
NW3 and NW4 are located at 08º24
'
38.2
''
N and
007º52
'
59.2
''
E, 08º21
'
24.9
''
N and 007º54
'
29.6
''
E,
08º24
'
04.1
''
N and 007º52
'
10.6
''
E and 08º25
'
56.3
''
N
and 007º53
'
49.3
''
E respectively. Columbite was
mined in all the four villages as represented in
Fig. 1.
2.3 Methods
2.3.1 Sample collection
Four sample locations were visited from all over
Nasarawa West, Nigeria, to conduct the
radiometry study. Three samples will be collected
from each sample area to make twelve samples
of soil. The samples were collected at 0.5 m
depth level from the surface of the soil. From
each area, as stated earlier, three samples were
collected as follows. Firstly from the mining spot,
secondly from a distance of 100 m away from the
mining spot, and thirdly, from the river area within
the mining spot. The collected samples were
sealed in a labeled polythene bags and enclose
into one sack for easiest transportation from the
mining or sample point to the house.
Meanwhile, when collecting the sample from the
mining spot, Inspector Alert Nuclear Radiation
Monitor was set at one meter above the ground
to measure the physical activity concentration of
the radionuclides present in the soil. In addition,
Global Positioning System (GPS) was used to
take the altitude of the area.
2.3.2 Sample preparation
The collected wet samples were taken to the
laboratory and left open for a minimum of 24
hours to dry under ambient temperature. The
samples were grounded using mortar and pestle
and allowed to pass through 5 mm-mesh sieve to
remove larger object and make it fine powder.
The samples were packed to fill 7 cm by 6 cm
cylindrical plastic container. Each container
accommodated 300 g of sample. They were
carefully sealed so as to prevent radon escape
and then stored for a minimum of 24 days to
allow radium attain equilibrium with the
daughters.
2.3.3 Sample analysis
Gamma-ray spectrometry technique was
employed in the spectral collection of the
prepared sample using the higher energy region
of the gamma-lines.
2.4 Data Analysis
The principal primordial radionuclides that was
discuss for all the radiological parameters
(Radium Equivalent Activity Ra
eq
, Absorbed
Dose Rate, Effective Dose Rate, External Hazard
Index H
(ex)
and Internal Hazard Index H
(in)
) in
this case are
226
Ra,
232
Th and
40
K.
Rilwan et al.;
AJR2P, 3(1): 8-16, 2020; Article no.AJR2P.53523
10
Table 1. Using items in the radiometric study
Materials
Specifications
Inspector Alert Nuclear
Radiation Monitor
This is a health and safety instrument that is optimized to detect
the physical levels of activity concentration of the radionuclides
present in the environment.
Global Positioning System
(G.P.S)
This is a space-based satellite navigation system that provides
location and time information in all weather, anywhere or near the
earth. This was used to locate the mining sites.
Disposable Hand Glove This is a shielding material used to protect the hands and fingers
from contacting any radioactive source.
Measuring Tape This was used to measure the depth of the pit and also to
measure the distance between two points.
Masking Adhesive Tape This was used to label the samples for easier identification.
Marker pen This was used to mark the masking tape attached to the
polythene bag for easy identification of the soil samples.
Mortar and Pestle This was used to ground the collected samples after being dried
at 60ºC to 80ºC for 24 hours in order to maintain the radioactive
equilibrium.
5mm-Mesh Sieve This was used to sieve the grounded samples in order to remove
any larger particles in it and make it a powder.
Cylindrical Plastic Container The sieved powder was packed into a cylindrical plastic container
and the cover will be sealed with a masking tape to prevent it from
any external radiation.
Electronic Analytical Balance The sealed containers were placed on the electronic analytical
balance to measure its weight in grams.
Cutlass This was used for clearing of the mining sites also for shallow
digging.
Sealer This was used to seal the sieved and labeled samples in their
respective container in order to avoid leakage also to prevent the
escape of gaseous
222
Rn from the sample.
Sodium Iodide-Thalium
Gamma Spectroscopic System
This is an instrument set in the laboratory, which was used to
analyze the soil samples.
2.4.1 Radium Equivalent Activity (Ra
eq
)
This first index can be calculated using [6]
relation:
Ra
eq
= A
Ra
+ 1.43A
Th
+ 0.077A
K
(1)
Where A
Ra
, A
Th
and A
K
are the specific activities
of
226
Ra,
232
Th and
40
K in Bq/kg, respectively.
2.4.2 Absorbed dose rate
According to UNSCEAR [7], conversion
factors to transform specific activities A
Ra
, A
Th
and A
K
of
226
Ra,
232
Th and
40
K, respectively, in
absorbed dose rate at 1meter above the
ground (in nGy/hr by Bq/kg) are calculated by
relation:
D(nGy/hr) = 0.0417A
K
+ 0.462A
Ra
+ 0.604A
Th
(2)
Where A
Ra
, A
Th
and A
K
are the activities of
226
Ra,
232
Th and
40
K in Bq/kg, respectively.
2.4.3 Annual Gonadal Equivalent Dose
(AGED)
According to Alam, et al. [8], AGED is calculated
with given activity concentration of
226
Ra,
232
Th
and
40
K (in Bq/Kg) using the relation:
AGED (mSv/yr) = 3.09A
Ra
+ 4.18A
Th
+0.314A
K
(3)
Where, A
Ra
, A
Th
, and A
K
are the radioactivity
concentration of
226
Ra,
232
Th and
40
K (in Bq/Kg)
in soil samples respectively.
2.4.4 Activity concentration index
(Representative gamma index)
According to Alam, et al. [8], the activity
concentration index is given by:
I
r
=
+
+
(4)
Where, A
Ra
, A
Th
, and A
K
are the radioactivity
concentration of
226
Ra,
232
Th and
40
K (in Bq/Kg)
in soil samples respectively.
2.4.5
Annual Effective Dose Equivalent
(AEDE)
According to UNCEAR [9] Veiga, et al. [10],
AEDE is determined by the equations below.
AEDE (Outdoor) (mSv/y) = D (nGy/ h) × 8760h ×
0.7 Sv/Gy× 0.2 × 10
−6
And
AEDE (Indoor) (mSv/y) = D (nGy/h) ×8760h ×
0.7 Sv/Gy× 0.8 × 10
−6
2.4.6 Excess Lifetime Cancer Risk (ELCR)
According to Taskin,
et al. [11], Excess lifetime
cancer risk (ELCR) is given by;
ELCR = AEDE × DL × RF
Where AEDE is the Annual Effective Dose
Equivalent, DL is the average duration of life
/ life expectancy (estimated as 70 years), and
RF is the Risk Factor (Sv
-1
), i.e. fatal cancer risk
per Sievert.
2.4.7 External hazard index
According to Beretka and Mathew [6], can be
calculated using the equation:
Rilwan et al.;
AJR2P, 3(1): 8-16, 2020
; Article no.
11
Fig. 1. Map of study area
Annual Effective Dose Equivalent
According to UNCEAR [9] Veiga, et al. [10],
AEDE is determined by the equations below.
AEDE (Outdoor) (mSv/y) = D (nGy/ h) × 8760h ×
(5)
AEDE (Indoor) (mSv/y) = D (nGy/h) ×8760h ×
(6)
2.4.6 Excess Lifetime Cancer Risk (ELCR)
et al. [11], Excess lifetime
(7)
Where AEDE is the Annual Effective Dose
Equivalent, DL is the average duration of life
/ life expectancy (estimated as 70 years), and
), i.e. fatal cancer risk
According to Beretka and Mathew [6], can be
H
ex
=
+
+
Where A
ra
, A
th
and A
k
are activity concentrations
of
226
Ra,
232
Th and
40
K in Bq/kg respectively.
2.4.8 Internal hazard index
According to Beretka and Mathew [6], is given by
the formula
H
in
=
+
+
Where A
ra
, A
th
and A
k
are activity concentrations
of
226
Ra,
232
Th and
40
K in Bq/kg respectively.
3.
RESULTS AND DISCUSSION
3.1 Results
This shows the experimental results obtained
from the spectra of twelve
soil samples under
investigation. For the effective computation of the
experimental data from Count Dose Rate (cpm)
to Exposure Dose Rate (µSvhr
Dose Rate (nGyhr
-1
), Annual Effective Dose Rate
(mSvyr
-1
), Annual Gonadal Equivalent Dose Rate
(m
Sv/yr), Activity Concentration Index
; Article no.
AJR2P.53523
(8)
are activity concentrations
K in Bq/kg respectively.
According to Beretka and Mathew [6], is given by
(9)
are activity concentrations
K in Bq/kg respectively.
RESULTS AND DISCUSSION
This shows the experimental results obtained
soil samples under
investigation. For the effective computation of the
experimental data from Count Dose Rate (cpm)
to Exposure Dose Rate (µSvhr
-1
), Absorbed
), Annual Effective Dose Rate
), Annual Gonadal Equivalent Dose Rate
Sv/yr), Activity Concentration Index
Rilwan et al.;
AJR2P, 3(1): 8-16, 2020; Article no.AJR2P.53523
12
(representative gamma index), Excess Lifetime
Cancer Risk, External Hazard Index (Bq/Kg) and
Internal Hazard Index (Bq/Kg); Equation 1 to 9
was used and the results are presented in the
Table 2.
3.2 Result Analysis
The data in Table 2 were used to plot chats (see
Figs. 2 to 11) so as to analyze the results and
compare them with those of regulatory bodies.
3.3 Discussion
From Table 2 and the charts plotted it is possible
to see that, all the locations have their Radium
Equivalent Activity ranging between 100.39
Bq/Kg and 197.40 Bq/Kg with a mean value of
161.44 Bq/Kg. The Gamma Absorbed Dose
Rates calculated ranged from 44.85 nGy/hr to
90.71 nGy/hr with the mean of 73.68 nGy/hr.
Annual Gonadal Equivalent Dose (AGED)
obtained ranged from 315.77 mSv/yr to 640.91
mSv/yr with the mean of 519.19 mSv/yr. Activity
Concentration Index (ACI) calculated for the
locations ranged from 0.73 to 1.45 with the
mean value of 1.18. The AEDE (outdoor) value
ranges between 0.055 mSv/yr and 0.111 mSv/yr
with the mean of 0.090 mSv/yr. On the other
hand, the AEDE (indoor) value ranged from
0.220 mSv/yr to 0.445 mSv/yr, with the mean
value of 0.361 mSv/yr. Excess Lifetime Cancer
Risk Index (ELCR) obtained ranged from 00.770
to 1.558 with the mean value of 1.265 and from
0.193 to 0.389 with the mean value of 0.317 for
outdoor and indoor respectively. External and
Internal Hazard indices ranged from 0.271 Bq/kg
to 0.533 Bq/kg and 0.289 Bq/kg to 0.675 Bq/kg
as well as mean values of 0.435 Bq/kg and 0.512
Bq/kg respectively. The results showed trends
that are generally high for most radiation
hazard indices calculated except for few
indices whose values are below the
recommended thresholds.
Fig. 2. Radium Equivalent Activity (Ra
eq
) compared with the threshold
Fig. 3. Gamma absorbed dose rate compared with the threshold
Fig. 4. Annual Gonadal Equivalent Dose (AGED) compared with the threshold
0
200
400
NW1 A
NW1 B
NW1 C
NW2 A
NW2 B
NW2 C
NW3 A
NW3 B
NW3 C
NW4 A
NW4 B
NW4 C
Radium Equivalent Activity (Raeq)
Theshold (370Bq/kg)
0
100
NW1
A
NW1
B
NW1
C
NW2
A
NW2
B
NW2
C
NW3
A
NW3
B
NW3
C
NW4
A
NW4
B
NW4
C
Gamma Absorbed Dose Rate (nGy/hr) Theshold (89nGy/hr)
0
200
400
600
800
NW1 A
NW1 B
NW1 C
NW2 A
NW2 B
NW2 C
NW3 A
NW3 B
NW3 C
NW4 A
NW4 B
NW4 C
Annual Gonadal Equivalent Dose (mSv/yr) Theshold (300mSv/yr)
Rilwan et al.;
AJR2P, 3(1): 8-16, 2020; Article no.AJR2P.53523
13
Table 2. Evaluated results for radiation hazard indices
Sample
Code
Ra
eq
(Bq/kg)
G.A.D.R
(nGy/hr)
A.G.E.D
(mSv/yr)
Iγr
(Bq/kg)
AEDE Outdoor
(mSv/yr)
AEDE Indoor
(mSv/yr)
E.L.C.R Indoor
(mSv/yr)
E.L.C.R Outdoor
(mSv/yr)
H
ex
(Bq/kg)
H
in
(Bq/kg)
NW1A 177.54 80.99 572.87 1.31 0.099 0.397 1.390 0.347 0.479 0.532
NW1B 162.74 74.65 527.55 1.20 0.092 0.366 1.281 0.322 0.439 0.507
NW1C 164.62 75.73 534.00 1.21 0.093 0.372 1.302 0.326 0.445 0.535
NW2A 100.39 44.85 315.77 0.73 0.055 0.220 0.770 0.193 0.271 0.289
NW2B 102.27 46.47 326.26 0.74 0.057 0.228 0.798 0.200 0.276 0.332
NW2C 197.40 90.71 640.40 1.45 0.111 0.445 1.558 0.389 0.533 0.529
NW3A 153.54 67.08 460.64 1.07 0.082 0.329 1.152 0.287 0.415 0.536
NW3B 170.95 78.70 556.02 1.26 0.097 0.386 1.351 0.340 0.462 0.552
NW3C 189.00 89.13 640.91 1.43 0.109 0.437 1.530 0.382 0.505 0.554
NW4A 181.35 83.03 584.22 1.32 0.102 0.407 1.425 0.357 0.489 0.592
NW4B 195.30 87.27 605.22 1.38 0.107 0.428 1.498 0.375 0.527 0.675
NW4C 142.16 65.55 466.44 1.06 0.080 0.322 1.127 0.280 0.384 0.415
Range 100.39-197.40 44.85-90.71 315.77-640.91 0.73-1.45 0.055-0.111 0.220-0.445 0.770-1.558 0.193-0.389 0.271-0.533 0.289-0.675
Mean 161.44 73.68 519.19 1.18 0.090 0.361 1.265 0.317 0.435 0.512
Rilwan et al.;
AJR2P, 3(1): 8-16, 2020; Article no.AJR2P.53523
14
Fig. 5. Activity Concentration Index (ACI) compared with the threshold
Fig. 6. Annual Effective Dose Equivalent, AEDE (Outdoor) compared with the threshold
Fig. 7. Annual Effective Dose Equivalent, AEDE (Indoor) compared with the threshold
Fig. 8. Excess lifetime cancer risk (Outdoor), compared with the threshold
0
0.5
1
1.5
2
NW1 A
NW1 B
NW1 C
NW2 A
NW2 B
NW2 C
NW3 A
NW3 B
NW3 C
NW4 A
NW4 B
NW4 C
Activity Concentration Index (Representative Gamma Index)
Theshold (1.0Bq/kg)
0
0.02
0.04
0.06
0.08
0.1
0.12
NW1 A
NW1 B
NW1 C
NW2 A
NW2 B
NW2 C
NW3 A
NW3 B
NW3 C
NW4 A
NW4 B
NW4 C
Annual Effective Dose Equivalent (Outdoor), (mSv/yr)
Theshold (0.07mSv/yr)
0
0.2
0.4
0.6
NW1 A
NW1 B
NW1 C
NW2 A
NW2 B
NW2 C
NW3 A
NW3 B
NW3 C
NW4 A
NW4 B
NW4 C
Annual Effective Dose Equivalent (Indoor), (mSv/yr)
Theshold (0.45mSv/yr)
0
0.2
0.4
0.6
NW1 A
NW1 B
NW1 C
NW2 A
NW2 B
NW2 C
NW3 A
NW3 B
NW3 C
NW4 A
NW4 B
NW4 C
Excess Lifetime Cancer Risk (Outdoor), (mSv/yr)
Theshold (0.00029mSv/yr)
Rilwan et al.;
AJR2P, 3(1): 8-16, 2020; Article no.AJR2P.53523
15
Fig. 9. Excess lifetime cancer risk (Indoor) compared with the threshold
Fig. 10. External Hazard Index (H
ex
) compared with the threshold
Fig. 11. Internal Hazard Index (H
in
) compared with the threshold
4. CONCLUSION
Therefore, it can be concluded that, there may be
serious immediate radiological effects to the
populace and the environment in these areas
except for few locations where the risk due to
radiation is less significant even though, it can be
recommended that, all the locations may need
further investigation and monitoring using the
High Purity Germanium (HPGe) detector for the
locations.
COMPETING INTERESTS
Authors have declared that no competing
interests exist.
REFERENCES
1. Pujol L, Sanechez-Cebeza JA. Natural and
and artificial radioactivity in surface waters
of the Ebro River Basin (Northeast Spain).
Journal of Environ, Radioactivity. 2000;51:
181–210.
2. Solomon AO. A study of natural radiation
levels and distribution of dose rates within
the younger granites province of Nigeria. A
Ph.D Thesis, University of Jos, Nigeria.
2005;1:12.
3. Dinh Chau N, Dulinski M, Jodlowski P,
Nowak J, Rozanski K, Sleziak M,
Wachniew P. Natural radioactivity in
0
0.5
1
1.5
2
NW1 A
NW1 B
NW1 C
NW2 A
NW2 B
NW2 C
NW3 A
NW3 B
NW3 C
NW4 A
NW4 B
NW4 C
Excess Lifetime Cancer Risk (Indoor), (mSv/yr) Theshold (0.00029mSv/yr)
0
0.5
1
1.5
NW1 A
NW1 B
NW1 C
NW2 A
NW2 B
NW2 C
NW3 A
NW3 B
NW3 C
NW4 A
NW4 B
NW4 C
External Hazard Index (Bq/kg)
Theshold (1.0Bq/kg)
0
0.5
1
1.5
NW1 A
NW1 B
NW1 C
NW2 A
NW2 B
NW2 C
NW3 A
NW3 B
NW3 C
NW4 A
NW4 B
NW4 C
Internal Hazard Index (Bq/kg)
Theshold (1.0Bq/kg)
Rilwan et al.;
AJR2P, 3(1): 8-16, 2020; Article no.AJR2P.53523
16
groundwater–A review. Isotopes in
Environmental and Health Studies. 2011;
47(4):415-437.
4. Karahan G, Ozturk N, Ahmed B. Natural
radioactivity in various surface waters in
Istanbul, Turkey. Water Resources. 2000;
24:4367–70.
5. Nguelem EJM, Darko EO, Ndontchueng
MM, Schandorf C, Akiti TT, Muhulo AP,
Bam EKP. The natural radioactivity in
groundwater from selected areas in greater
accra region of ghana by gross alpha and
gross beta measurements. Radiation
Protection and Environment. 2013;36(1):
14.
6. Beretka J, Mathew PJ. Natural radioactivity
of australian building materials, industrial
wastes and byproducts. Health Physics.
1985;48.
7. UNSCEAR. Exposure of public and
workers from various sources of radiation.
United Nation Scientific Committee on
Effect of Atomic Radiation UNSCEAR
Report. 1988;1:12.
8. Alam MN, Miah MMH, Chowdhury MI,
Kamal M, Ghose S, Islam MN, Mustafa
MN, Miah MSR. Radiation dose estimation
from radioactivity analysis of lime and
cement used in Bangladesh. Journal of
Environmental Radioactivity. 1999;4:
21.
9. UNCEAR. Radiological Protection Bulletin.
United Nations Scientific Committee on the
effect of Atomic Radiation No. 20000.
2000;224:21. New York.
10. Veiga RG, Sanches N, Anjos RM, Macario
K, Bastos J, Iguatemy M, Auiar JG, Santos
AM, Mosquera B, Carvalho C, Baptista
Filho M, Umisedo NK. Measurement of
natural radioactivity in Brazillian beach
sands. Journal of Radiation Measurement.
2006;41:189.
11. Taskin H, Karavus M, Ay P, Topozoglu A,
Hindiroglu S, Karahan G. Radionuclide
concentrations in soil and life time cancer
risk due to gamma radioactivity in
Kirklareli, Turkey. Journal of Environmental
Radioactivity. 2009;35:53.
_________________________________________________________________________________
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provided the original work is properly cited.
Peer-review history:
The peer review history for this paper can be accessed here:
http://www.sdiarticle4.com/review-history/53523