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Evaluation of Radiation Hazard Indices in Mining Sites of Nasarawa State, Nigeria

Authors:
  • Nigerian Army University, Biu.
  • National Agency for Science and Engineering Infrastructure, Abuja -Nigeria

Abstract and Figures

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.
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*Corresponding author: E-mail: rilwanusmanloko4@gmail.com;
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
AJR2P.53523
(8)
(9)
-1
), Absorbed
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.
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... Naturally occurring radioactive materials (NORMs) are known as all the radionuclides existing naturally in the environment, which happens to be the primordial radionuclides 40 K, 232 Th and 238 Ra, and their decay products exist in different amounts within the earth [1][2][3][4]. Mostly, the concentration of NORMs in all substances in the environment can be neglected, but disposal of large quantities of certain minerals (mining) containing 40 K, 232 Th and 226 Ra and other radionuclides in the decay series of Th and U from the earth crust results in increase in the radionuclides concentrations [4][5][6][7][8][9]. This research will look at the radiological safety assessment of quarry Processing Site in Keffi, Nigeria Experimental Soil samples collection and preparation Samples of dry Soil were collected from five different processing site (Pyanku, Ungwan Kwara, Yalwa, Ungwan Tanko and Attab Filling Station) of Keffi, Nigeria. ...
... S. Smith's observation of the Virgo Cluster in 1936 also supports this conclusion [4]. An important evidence for the existence of dark matter comes from the 1970 study by Vera Rubin and Kent Ford on the rotation velocity of stars in the Andromeda Nebula [5]. Using high-precision spectral measurements, they can detect the relationship between the speed and distance of peripheral stars away from the galactic nucleus. ...
... S.Smith's observation of the Virgo Cluster in 19 also supports this conclusion [4]. An important evidence for t existence of dark matter comes from the 1970 study by Vera Rubin a Kent Ford on the rotation velocity of stars in the Andromeda Nebu [5].Using high-precision spectral measurements, they can detect t relationship between the speed and distance of peripheral stars aw from the galactic nucleus.According to Newton's law of gravity, if t mass of a galaxy is mainly concentrated on the visible stars in t nucleus of the galaxy, the velocity of the stars around the gala will decrease with the distance. But observations show that t velocity of stars around the galaxy is constant over a considerab range. ...
Article
Full-text available
Disposal of large quantities of certain minerals (mining) containing 40 K, 232 Th and 226 Ra and other radionuclides in the decay series of Th and U from the earth crust results in increase in the radionuclides concentrations. This research looks at the radiological safety assessment of quarry Processing Site in Keffi, Nigeria. The activity concentration of 226 Ra, 232 Th and 40 K in the five (5) different Soil samples, varied widely as 10.54±3.040 Bq/ kg, 2.61±1.170 Bq/kg and 36.99 ± 7.490 Bq/kg respectively. Ungwan Tanko (UTN) has the highest activity concentration of 14.90 ± 2.30 Bq/kg for 226 Ra while Pyanku (PYK) has the highest activity concentration of 4.52 ± 0.32 Bq/kg for 232 Th. Activity concentration of 40 K was highest (57.32 ± 2.530 Bq/kg) in Ungwan Kwara (UKW). It was also observed that Yalwa (YLW) had the lowest activity concentration of 02.20 ± 1.31 Bq/kg for 226 Ra, while Ungwan Tanko (UTN) had the lowest activity concentration values of 1.03 ± 1.74 Bq/kg for 232 Th and Attab Fueling Station (AFS) had the lowest activity concentration values of 13.67 ± 15.73 Bq/kg for 40 K. Radium equivalent activity Raeq (Bq/kg), alpha index, internal hazard index, and total cancer risk 17.52 Bq/kg 0.055, 0.077 and 6.82 x 10-7 respectively. Based on the results presented, the present quarry processing sites in Keffi has less effect on ingestion rate of Soil and may poses no radiological risk to the population.
... Heavy metals are the main pollutants and elements of risk in drinking water [3]. Investigation on water contamination by heavy metals has become the prime focus of environmental scientists in recent years [4]. More attention should be given to toxic heavy elements because of bio accumulation and bio magnification potential, and their persistence in the environment. ...
Article
Full-text available
It is evidently clear that water is one of the prime elements responsible for life on earth. Regrettably, even this small portion of fresh water is under pressure due to anthropogenic sources that results from rapid growth in population and industrial activities. Heavy metals are the main pollutants and elements of risk in drinking water. The results of the Assessment of Heavy Metals Concentration in some Selected Water Sources across Toto Local Government Area of Nasarawa State, Nigeria using Micro Plasma Atomic Emission Spectrometer have been presented. Four heavy metals along with their respective concentrations in mg/l (Zn (0.35), Cu (0.02), Pd (0.04) and Ni (0.003) were found in the water samples. One of the major points of concern in this research is the concentration of Lead (Pb) in all the water samples under investigation which was found to be higher than the World recommended limit of 0.01 mg/l. However, finding of this study have revealed that the mean Concentration of the analyzed heavy metals in all the water samples arranged in decreasing order is Zn > Pb > Cu > Ni. It was also found that the Mean Daily Intake in mg/l/day, carcinogenic risk assessments (Risk Pathway and Total Risk) and the non-carcinogenic risk assessments (Hazard Quotient and Hazard Index) were found to be lower than the WHO's recommended value of unity in all the heavy metals for all locations under investigation. This implies that the mean concentration level of most of heavy metals like Zn, Cu and Ni in those areas is not significant and may not cause radiological hazard to the populace unless when accumulated over a long period of time. However, high concentration of lead was recorded which could be attributed to both natural and man-made activities such as geological formation of the study Area, fertilizer, herbiside, pestiside application by farmers, artisenanl mining activities, activities of metal scrap businesses taking place in the area and so on. Hence, it can be concluded that the mean concentration level of heavy metals in those areas may cause health hazard to the populace as a result of accumulation of Pb in the body over time.
... The miners brought soil and stones rich in tin mineral to the surface for processing, the tailings generated are exposed to wind and the prevailing weather conditions resulting in transportation of the particles containing radionuclides to once uncontaminated areas [7]. The populace relies on untreated ground water (shallow wells and boreholes) for drinking, edible plants as their daily food and other household activities which may contain high radon concentrations [8]. This work may call the attention of the stakeholders to give more attention to the environmental impacts of NORMs and motivate further research into controlling NORMs radiation levels in the country [9]. ...
Article
Full-text available
Naturally occurring radioactive materials (NORMs) refers to all the radionuclides that exist in the environment naturally, which are the primordial radionuclides 40 K, 232 Th and 226 Ra, and their decay products which are present in varying amounts within the earth crust. This study reports the extent of contamination and pollution of soil, water and edible plant by the concentration of 40 K, 226 Ra and 232 Th and associated radiological parameters of Jos East and Jos South artisanal tin mining areas in Plateau State, Nigeria. The results showed that the contamination factors of Soil in Jos East have the total values in trend with 232 Th (1.145) > 40 K (0.779) > 226 Ra (0.729) while that of Jos South have the total values in trend with 226 Ra (0.914) > 232 Th (0.914) > 40 K (0.816). The contamination factors of water in Jos East have the total values in trend with 232 Th (1.116) > 40 K (0.756) > 226 Ra (0.696) while that of Jos South has the total values in trend with 232 Th (0.890) > 226 Ra (0.889) > 40 K (0.791). The contamination factors of Edible Plants in Jos East have the total values in trend with 232 Th (1.088) > 40 K (0.731) > 226 Ra (0.662) while that of Edible Plants in Jos South have the total values in trend with 226 Ra (0.925) > 232 Th (0.870) > 40 K (0.859). The pollution load index of radioactive trace elements from soil samples of Jos East is in decreasing order trend with 232 Th (3.985) > 40 K (0.023) > 226 Ra (0.013) with the total value of 1.340, on the other hand, that of Jos South is in decreasing order trend with 226 Ra (0.328) > 232 Th (0.172) > 40 K (0.043) with the total value of 0.181. The pollution load index of radioactive trace elements from water samples of Jos East is in decreasing order trend with 232 Th (2.910) > 40 K (0.015) > 226 Ra (0.007) with the total value of 0.977, on the other hand, that of Jos South is in decreasing order trend with 226 Ra (0.130) > 232 Th (0.077) > 40 K (0.018) with the total value of 0.120. The pollution load index of radioactive trace elements from edible plant samples of Jos East is in decreasing order trend with 232 Th (2.107) > 40 K (0.009) > 226 Ra (0.004) with the total value of 0.707, on the other hand, that of Jos South is in decreasing order trend with 226 Ra (0.130) > 232 Th (0.077) > 40 K (0.018) with the total value of 0.075. Based on the results presented, the soil, water and edible plants in Jos East is moderately contaminated and highly polluted with Thorium-232 (232 Th) but less contaminated with Radium-226 (226 Ra) and Potassium-40 (40 K). Meanwhile, Jos South have less contaminated soil for both Thorium-232 (232 Th), Radium-226 (226 Ra) and Potassium-40 (40 K) considering the World Health Organization recommended limit of CF < 1. Therefore, it can be concluded that the soil, water and plants in the Jos East are moderately contaminated and highly polluted, which calls for serious concern and regulatory control.
... Genotoxic carcinogens are those which initiate carcinogenesis by direct interaction with DNA, resulting in DNA damage or chromosomal aberrations that can be detected by genotoxicity tests [3]. On the other hand, nongenotoxic carcinogens are agents that indirectly interact with the DNA, causing indirect modification to DNA structure, amount, or function that may result in altered gene expression or signal transduction [4]. Substances that induce tumors in animals are also considered human carcinogens until proven otherwise [5]. ...
Article
Full-text available
Carcinogenic substances are those that induce tumors (benign or malignant), increase their incidence or malignancy or shorten the time of tumor occurrence when they get into the body through inhalation, injection, dermal application or ingestion. The aim of this work is to unveil the extent to which radioactive trace elements (40 K, 226 Ra and 232 Th) accumulates in soil, water and edible plants and assess their carcinogenic role to biological tissue that might result in cancer. The results showed that the soil in Barkin Ladi, has the mean I geo decreasing in the order of 40 K (7.744) > 232 Th (4.642) > 226 Ra (3.886). The soil in Mangu, has the mean I geo decreasing in the order of 40 K (7.705) > 232 Th (4.382) > 226 Ra (4.128). The water in Barkin Ladi, has the mean I geo decreasing in the order of 232 Th 40 K (7.685) > 232 Th (4.598) > 226 Ra (3.804). The water in Mangu, has the mean I geo decreasing in the order of 40 K (7.575) > 232 Th (4.303) > 226 Ra (4.037). The edible plants in Barkin Ladi, has the mean I geo decreasing in the order of 40 K (7.582) > 232 Th (4.496) > 226 Ra (3.540). The edible plants in Mangu, has the mean I geo decreasing in the order of 40 K (7.520) > 232 Th (4.122) > 226 Ra (3.817). Based on the findings of this study, 100 % of the area under study has its geo-accumulation index ratio "> 1" which implies higher accumulation of trace element in soil, plant and water. It can therefore be concluded that the water, soil and edible plants in the study area are issue of health concern which on high consumption without regulatory control can lead to cancer effects, even though, researches of contamination factor and pollution load index of the radioactive trace elements in the study areas are recommended.
... Accumulation of radioactive trace elements in soils is accelerated by industrial and other human activities such as mining, smelting, cement-pollution, energy and fuel production, power transmission, traffic activities, intensive agriculture, sludge dumping and melting operations [1, 2,3,4,5,6]. Plants received these radioactive trace elements from soils through ionic exchange, redox reactions, precipitation-dissolution, and so on [7]. ...
Article
Full-text available
Accumulation of radioactive trace elements in soils is accelerated by industrial and other human activities such as mining, smelting, cement-pollution, energy and fuel production, power transmission, traffic activities, intensive agriculture, sludge dumping and melting operations. The aim of this work is to assess the contamination factor (CF) of radioactive traces like 40 K, 226 Ra and 232 Th. The results showed that the soil in Barkin Ladi, has mean CF decreased in the order of 232 Th (1.064) > 40 K (0.812) > 226 Ra (0.758). The soil in Mangu, has mean CF decreased in the order of 232 Th (0.922) > 226 Ra (0.878) > 40 K (0.809). The water in Barkin Ladi, has mean CF decreased in the order of 232 Th (1.033) > 40 K (0.783) > 226 Ra (0.719). The water in Mangu, has mean CF based on sample points decreased in the order of 232 Th (0.874) > 226 Ra (0.826) > 40 K (0.749). The edible plants in Barkin Ladi, has mean CF decreased in the order of 232 Th (0.961) > 40 K (0.737) > 226 Ra (0.614). The edible plants in Mangu, has mean CF decreased in the order of 226 Ra (0.883) > 232 Th (0.797) > 40 K (0.782). Based on the findings of this study, 75 % of the area under study has its contamination factor ratio "> 1" which implies higher contamination of trace element in soil, plant and water. It can be concluded that the water, soil and edible plants in the study area are issue of health concern which on high consumption without regulatory control can lead to cancer effects, even though, researches of geo-accumulation index and pollution load index of the radioactive trace elements in the study areas are recommended.
... The minerals occurrence in this area is often associated with viscose biotite granite. This abundance of minerals results in the activities of mining and exploration in the area since 1904 [3,4]. The mining has been operating for the past 50 years, and radioactive nature of the minerals was realized not before 1974 [5,6]. ...
Article
Full-text available
Abundance of resinized biotite results in the activities of mining and exploration in the Jos since 1904. The mining has been operating for the past 50 years, and radioactive nature of the minerals was realized not before 1974. This work intends to unveil the extent to which K 40 , Ra 226 , and Th 232 transfers from soil to water and various species of food crops in Bassa. The results revealed that, the TF for different trace elements in soil-edible plants for all points decreased in the order P12 (0.716) > P04 (0.660) > P07 (0.581) > P02 (0.579) > P06 (0.574) > P10 (0.568) > P05 (0.542) > P08 (0.540) > P01 (0.534) > P09 (0.532) > P03 (0.520) > P11 (0.517). Considering the individual radioactive traces, the TF decreased in the following order: 232 Th (0.666) > 226 Ra (0.557) > 40 K (0.473). The total TF for different trace elements in soil-water for all points decreased in the order P04 (0.930) > P06 (0.787) > P07 (9.786) > P10 (0.780) > P08 (0.765) > P03 (0.759) > P11 (0.755) > P02 (0.720) > P01 (0.665) > P05 (0.600) > P12 (0.576) > P09 (0.398). Also considering the individual radioactive traces, the TF decreased in the order 232 Th (0.828) > 40 K (0.715) > 226 Ra (0.587). It can be concluded that the water and edible plants in the study area are good for public consumption, though, regular checking of radioactive traces in the study areas are recommended.
... Aggregation of radioactive trace elements in soils is instigated by industrial and other human activities such as mining, smelting, cement-pollution, energy and fuel production, power transmission, traffic activities, intensive agriculture, sludge dumping and melting operations [1,2,3,4,5,6,7]. Plants received these radioactive trace elements from soils through ionic exchange, redox reactions, precipitation-dissolution, and so on. ...
Article
Full-text available
Plants received these radioactive trace elements from soils through ionic exchange, redox reactions, precipitation-dissolution. The same trace elements can contaminate water through erosion, where radioactive trace elements are flushed to our rivers and streams and we consume them. Contamination factor of soil, water and edible plants is studied using an index called Contamination Factor (CF). The result revealed that, the total CF for different trace elements in soil based on sample points decreased in the order P06 (1..75), considering the individual trace elements, the total CF decreased in the 232 Th (1.90) > 40 K (1.21) > 226 Ra (0.92). The total CF for different trace elements in water based on sample points decreased in the order P06 (1.), considering the individual trace elements, the total CF decreased in the order: 232 Th (1.59) > 40 K (0.79) > 226 Ra (0.58). The total CF for different trace elements in edible plant based on sample points decreased in the order of Shuwaka (1.01)>Water Leaf (0.98)>Rogo (0.92)>Zogale (0.89)>Karkashi (0.83)>Kuka (0.81)>Kabeji (0.79)>Rama (0.77)>Yakuwa (0.75)>Ugu (0.58)>Alayyahu (0.47)>Yateya (0.46), considering the individual trace elements, the total CF decreased in the order 232 Th (1.28) > 40 K (0.55) > 226 Ra (0.48).
... With an area of 26,899 square kilometers, the State has an estimated population of about three million people. It is located between latitude 08°24'N and longitude 008°32' and 010°38' east [17][18][19] . ...
Article
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The association of radiation with matter, being it from external means (i.e. external sources) or from internal pollution of the body by toxic substances, can pose biological hazard which may show the clinical symptoms later. The nature and extent of these symptoms and the time they take to appear are a function of the amount of radiation absorbed and the rate at which it is received. This study aimed at assessing the health effects of radiation exposure to human sensitive organs across some selected mining sites of Plateau State Nigeria. Finding of this study have revealed that the mean D organ values for the lungs, ovaries, bone marrow, testes, kidney, liver and whole body for different mining points of Plateau State are 0.29 mSv/y, 0.26 mSv/y, 0.31 mSv/y, 0.36 mSv/y, 0.28 mSv/y, 0.21 mSv/y and 0.30 mSv/y respectively. From the findings presented, it can be concluded that the background radiation in Plateau State is not an issue of health concern in regards to sensitive organs and may not course immediate health effect except when accumulated over long period of time which may cause cancer to the indoor members on approximately seventy years of exposure.
... Furthermore, flowing water encounters shelves, sedimentary rocks, igneous rock s and phosphate rocks all of which are radioactive (Sanchi and Honey Man 1989). All these contribute to the level of radioactivity in water [4]. ...
Article
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Water is an essential substance for human existence and his environment but water sources are often polluted by human activities and some natural phenomena which arises from waste and sewage disposal into rivers and streams. This study intends to assess the gross alpha and beta in Gashua, Yobe state, Nigeria using the protean MPC-2000-DP Proportional counter. The results revealed that, for the gross alpha, the activities concentration varied from 0.091 ± 0.0058 to 1.990 ± 0.1010 mSv/yr with an average of 0.574 ± 0.0308 mSv/yr, while for the gross beta, the values varied from 0.55 ± 0.014 to 9.47 ± 0.240 mSv/yr with an average of 2.91 ± 0.068 mSv/yr. Also, for the alpha, the CED values for the adult varied from 0.146 ± 0.009 to 3.196 ± 0.162 mSv/yr with an average of 0.922 ± 0.049 mSv/yr, the CED values for the children varied from 0.073 ± 0.006 to 1.598 ± 0.081 mSv/yr with an average of 0.461 ± 0.025 mSv/yr and the CED values for the infants varied from 0.037 ± 0.002 to 0.799 ± 0.041 mSv/yr with an average of 0.231 ± 0.012 mSv/yr. For the beta, the CED values for the adult varied from 0.883 ± 0.022 to 15.21 ± 0.385 mSv/yr with an average of 4.667 ± 0.110 mSv/yr, the CED values for the children varied from 0.442 ± 0.011 to 7.604 ± 0.193 mSv/ yr with an average of 2.334 ± 0.055 mSv/yr and the CED values for the infants varied from 0.221 ± 0.006 to 3.802 ± 0.096 mSv/yr with an average of 1.167 ± 0.027 mSv/yr. Based on the findings presented, most of these values are found to be above the World Health Organization recommended limit of 1 Bq/l except for few points. It is therefore assumed that the aggressive gross alpha activity might be attributed to uranium and radium and its alpha daughters which are contained in some of agro chemicals such as fertilizers while enhancement of gross beta activity in the area may be due to the increase in potassium concentration. agricultural fertilizers product contained various trace of elements such as Uranium and Thorium decay series members and 40K. It is therefore concluded that the water in the area under investigation is not a safe water for drinking, for this reason, it strongly recommended that there should be public health law, to safeguard the lives of the inhabitants, seasonal study of the radioactivity of ground water in the mentioned areas should be conducted to check whether the radio activity is affected by season and there is also need to extend these research in the entire Gashua town so as to have a comprehensive study of the entire ground water in the town.
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The objective of this study is to evaluate and map soil radionuclides' activity concentrations and environmental outdoor gamma dose rates (terrestrial and cosmic) in Kirklareli, Turkey. The excess lifetime cancer risks are also calculated. Outdoor gamma dose rates were determined in 230 sampling stations and soil samples were taken from 177 locations. The coordinates of the readings were determined by the Global Positioning System (GPS). The outdoor gamma dose rates were determined by Eberline smart portable device (ESP-2) and measurements were taken in air for two minutes at 1 m from the ground. The average outdoor gamma dose rate was 118 ± 34 nGy h−1. Annual effective gamma dose of Kirklareli was 144 μSv and the excess lifetime cancer risk of 5.0 × 10−4. Soil samples were analyzed by gamma spectroscopy. The average 226Ra, 238U, 232Th, 137Cs, and 40K activities were 37 ± 18 Bq kg−1, 28 ± 13 Bq kg−1, 40 ± 18 Bq kg−1, 8 ± 5 Bq kg−1 and 667 ± 281 Bq kg−1, respectively. The average soil radionuclides' concentrations of Kirklareli were within the worldwide range although some extreme values had been determined. Annual effective gamma doses and the excess lifetime risks of cancer were higher than the world's average.
Article
The radioactivity concentrations of 232Th, 226Ra, 40K and 137Cs were measured using high-resolution γ-ray spectrometry in limestone, powdered lime, by-product lime and cement used in Bangladesh. The activity concentrations, Ra equivalent activities, representative level index values for all samples and the effective dose equivalents due to the intake of the above-mentioned radionuclides in limestone and powdered lime by the adult group were estimated. The mean activity concentrations of 232Th, 226Ra and 40K were 60.8, 60.2 and 928Bqkg-1, respectively for limestone, 107, 68.0 and 1660Bqkg-1, respectively, for powdered lime and 83.0, 31.0 and 972 Bq kg-1, respectively, for by-product lime. For cement, the mean activity concentrations of 232Th, 226Ra and 40K were observed to be 54.3, 29.7 and 523Bqkg-1, respectively. The presence of 137Cs was not detectable in any of the studied samples. The measured average activities of 232Th, 226Ra and 40K for all samples were relatively higher than the world typical values except for 226Ra in cement and by-product lime. The calculated mean Ra equivalent values for limestone, powdered lime, by-product lime and cement were 219, 349, 224 and 148 Bq kg-1, respectively. The corresponding representative level index values were found to be 1.63, 2.63, 1.68 and 1.09, respectively. The mean effective dose equivalent values of 232Th, 226Ra and 40K for limestone were 56.5×10-7, 41.6×10-8 and 50.8×10-10 Svg-1, respectively, and those for powdered lime were 99.5×10-7, 46.9×10-8 and 91.3×10-10 Svg-1, respectively.
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Gross-α and gross-β, activities of eight well and five tap water samples taken in İstanbul were determined. Ra226, Rn222, Pb214, Bi214, K40, Cs137 activity concentrations in four lake, four sea water, one snow and one rain water samples were also analyzed in order to determine their radioactivity. The results obtained showed that, in general, natural activities in drinking water samples did not exceed WHO and ITS guidelines. In sea and lake water, four samples were over WHO and TSI guidelines. Concentrations ranging from 0.007 to 0.04 Bq l−1 and from 0.02 to 0.1 Bq l−1 were observed for drinking water and the gross-α and gross-β activities, respectively. For all samples the gross-β activities were higher than the corresponding gross-α activities. In order to evaluate the annual effective dose equilavent of ingestion of these waters, a conservative dosimetric calculation was carried out using dose conversion factor suggested by the ICRP. An average annual effective dose equivalent of 0.84 μSv y−1 for Ra226 was calculated.
Article
A radiological characterisation of surface waters of the Ebro river basin was carried out during November 1994. For this purpose, 75 water samples were collected from points distributed throughout the Ebro river basin. Analysis included gross alpha and gross beta activities, relevant natural radionuclides (, , -uranium total-) and several artificial radionuclides (, and radiocaesium). Mean gross alpha and gross beta activities in surface waters of the river's main course were 0.095±0.004 and 0.213±0.012 Bq l−1, respectively. Mean activities of , and uranium (total) were 0.132±0.009, 0.0282±0.0008 and 0.053±0.006 Bq l−1, respectively. Regarding artificial radionuclides, the mean activity was 6.6±0.3 mBq l−1, was detected in 8% of the samples, and radiocaesium was not detected in any sample. It is estimated that almost 100% of gross alpha and 97% of gross beta activities of surface waters in the Ebro river came from natural sources. Furthermore, results showed that the geological setting, large cities, agricultural areas and dams strongly influence the occurrence of natural radionuclides. Contamination from nuclear power plants located along the river was not detected. Finally, we estimated that the annual dose equivalent due to the hypothetical ingestion of Ebro river waters was 7.59 μSv y−1, which represented only 0.3% of the average annual effective dose attributable to natural background radiation in the area.
Article
A THESIS SUBMITTED TO THE SCHOOL OF POSTGRADUATE STUDIES, UNIVERSITY OF JOS, IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE AWARD OF THE DEGREE OF DOCTOR OF PHILOSOPHY IN UNIVERSITY OF JOS A study of natural radiation levels and distribution of dose rates in parts of the Younger Granite Province of Nigeria constitutes this work. It has established the extent and distribution of various parameters of ionizing radiation across the area. By using a combined solid scintillation and gas filled radiation detection techniques, gross gamma as well as gross alpha/beta radiations were detected and measured within the different rock units, the result of which show that radiation levels are high within the younger granites and in parts of the basement areas but low within the basalts. Radiation maps prepared for this area show a good correlation with existing geological maps of the area signifying that natural terrestrial radiation signatures can be used as a tool for regional geological mappings especially in poorly exposed plains. The maps indicate that absorbed dose rates in air range from 0.030-0.431 μGyh-1, while dose equivalents and effective dose rates are well in excess of 1mSv/yr maximum permissible limits in some areas, suggesting a reasonably good chance of radiation hazards in those places. Highest values were found within the Ririwai Sheet 126, attributable to high concentration of radionuclides within both the peralkaline and non-peralkaline granites that constitute the complex. People living in areas identified with high background radiation levels in this study should therefore be made aware of the potential radiation related health problems, while government should also do more to stop the common practice of using mine wastes for foundation fillings and block construction because of the radiological implications.
Exposure of public and workers from various sources of radiation
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.
Measurement of natural radioactivity in Brazillian beach sands
  • R G Veiga
  • N Sanches
  • R M Anjos
  • K Macario
  • J Bastos
  • M Iguatemy
  • J G Auiar
  • A M Santos
  • B Mosquera
  • C Carvalho
  • Baptista Filho
  • M Umisedo
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.