Journal of Environmental Protection, 2014, 5, 193-199
Published Online February 2014 (http://www.scirp.org/journal/jep )
http://dx.doi.org/10.4236/jep.2014.53023
OPEN ACCESS JEP
Analysis of Radium Isotopes in Surface Waters nearby a
Phosphate Mining with NORM at Santa Quitéria, Brazil
Wagner de S. Pereira
1,2
, Alphonse Kelecom
2
, Juliana R. de S. Pereira
3
1
Multidisciplinary Group of Radioprotection (GMR), Serviço de Radioproteção, Unidade de Tratamento de Minério, Indústrias
Nucleares do Brasil, Caldas, Brazil;
2
Laboratory of Radiobiology and Radiometry Pedro Lopes dos Santos (LARARA-PLS), Group
of Environmental Themes Assessment (GETA), Universidade Federal Fluminense (UFF), Niterói, Brazil;
3
Interdisciplinary Under-
Graduation in Science and Technology, Universidade Federal de Alfenas, Poços de Caldas, Brazil.
Email: pereiraws@gmail.com
Received November 30
th
, 2013; revised December 28
th
, 2013; accepted January 25
th
, 2014
Copyright © 2014 Wagner de S. Pereira et al. This is an open access article distributed under the Creative Commons Attribution
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ABSTRACT
The radium isotopes
226
Ra and
228
Ra were analyzed in surface water at six points in the neighborhood of a mine
of phosphate, associated with uranium, in the region of Santa Quitéria, state of Ceará, Brazil. Water samples
were collected during twenty months, filtered and the concentrations of activity determined in the soluble and
particulate phases. The results were analyzed using the Principal Component Analysis (PCA) for ordination of
environmental data, and also by ANOVA, Tukey and Z tests to compare sets of data considering the radionu-
clides, the two analyzed phases and the six collecting points. The PCA identified four groups that included all
collecting points, using aggregation features such as radionuclide and analyzed phase. The first group is com-
posed by the samples of
226
Ra in the soluble phase; the second group by samples of
226
Ra in the particulate phase;
the third one by
228
Ra in the soluble phase, and finally, the fourth group by
228
Ra in the particulate phase. This
last group has two discrepant points (01 and 06). Statistical analysis identified differences between the concen-
trations of activity of radionuclides (
228
Ra higher than
226
Ra) and in analyzed phases (soluble phase higher than
the particulate one) but showed no differences between sampled points.
KEYWORDS
Radioecology; Environmental Radioprotection; NORM Mining; Radium Isotopes; PCA
1. Introduction
Phosphate mining and processing can cause significant
radiological impacts due to the amount of radionuclides
present in the ore [1]. Phosphogypsum e.g., a by-product
of phosphate mining, is contaminated by heavy metals
and radionuclides, especially
226
Ra [2]. Mining of phos-
phate with associated Naturally Occurring Radioactive
Materials must thus be considered as a NORM activity.
There has been an increased awareness of the radio-
logical impacts of NORM non-nuclear mining pointing
that this activity may cause radioactive contamination
due to the by-products, wastes and to the installations
themselves [3]. In this respect, the environmental impact
was analyzed in three practices related to phosphate pro-
duction: mines, phosphate fertilizers factory and phos-
phate export platforms. Air particulates, soil, water (lake,
river and sea water), biota and plant samples were col-
lected and analyzed. An increase of natural radionuclides
in the surroundings of the three enterprises was observed,
with fallout being the principal contamination way [4].
Accordingly, the phosphate industry has been recently
included within the European regulatory scope.
226
Ra was
recognized as the major contaminant. It is found mainly
in the processing waters, and the major releasing way is
via the liquid effluents [5].
Located in the central-north region of the state of
Ceará, Brazil, the “Santa Quitéria” Unit is a phosphate
associated with uranium mining installation in predeve-
lopment stage that belongs to the “Indústrias Nucleares
do Brasil” (INB). The deposit has recoverable reserves of