Download 1. Title: High natural background radiation areas in Ramsar, Iran

1.
Title: High natural background radiation areas in Ramsar, Iran: can inhabitants feel safe?
Ali Shabestani Monfared, Farzad Jalali, Sadegh Sedaghat, Esmail Mansoorizade, Alireza Jarrahi,
Mahmood Hajiahmadi, Hamid Samavat
1
Department of Medical Physics, Babol University of Medical Sciences, Babol, Iran.
2
Department of Internal Medicine and Cardiology, Babol University of Medical Sciences, Babol, Iran.
3
Department of Oncology, Babol University of Medical Sciences, Babol, Iran.
4
Babol University of Medical Sciences, Babol, Iran.
5
Department of Epidemiology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
6
Department of Social Medicine, Babol University of Medical Sciences, Babol, Iran.
7
Department of Medical Physics, Hamedan University of Medical Sciences, Hamedan, Iran
Abstract
Ramsar, a coastal city in the northern part of Iran, has one of the highest levels of natural radiation known to
exist in an inhabited area. The study of the effects of high natural background radiation on human health
was the main goal of this investigation. We also compared some features in relation with the health
between residents of high and normal natural background radiation areas in Ramsar. These preliminary
results showed a lack of ill effects among the population in the high background radiation area. These
results may indicate that the risk from the high levels of natural background radiation may be less than the
predictions of the LNT model of radiation dose response.
2.
Title: Cancer incidence in areas with elevated levels of natural radiation
Author: S.M.J. Mortazavi, M. Ghiassi-Nejad, P.A. Karam, T. Ikushima, A. Niroomand-Rad, J.R. Cameron
Address: National Radiation Protection Department (NRPD), Iranian Nuclear Regulatory Authority (INRA),
PO Box 14155-4494, Tehran, Iran and Medical Physics Department, School of Medicine, Rafsanjan
University of Medical Sciences, Imam Ali Blvd. Rafsanjan, Iran. ' National Radiation Protection Department
(NRPD), Iranian Nuclear Regulatory Authority (INRA), PO Box 14155-4494, Tehran, Iran and Biophysics
Department, Tarbiat Modares University (TMU), Tehran, Iran. ' Department of Environmental Medicine,
University of Rochester, 601 Elmwood Ave Box HPH, Rochester, NY 14642, USA. ' Biology Division, Kyoto
University of Education, Kyoto 612- 8522, Kyoto, Japan. ' Department of Radiation Medicine, Georgetown
University, LL Bles Building, 3800 Reservoir Road NY, Washington DC 20007-2197, USA. ' Departments of
Medical Physics, Radiology and Physics, University of Wisconsin, Madison, WI, USA
Journal: Int. J. of Low Radiation, 2006 Vol.2, No.1/2, pp.20 - 27
Abstract: It has been reported that on reaching a certain level of cell damage the production of repair
enzymes is triggered which decreases the chromosome aberrations. If this happens, prolonged exposure to
high levels of natural radiation in areas with elevated levels of background radiation could decrease the
frequency of chromosome aberrations. Recent epidemiological studies indicated that there is an increased
risk of cancer in healthy individuals with high levels of chromosomal aberrations. Studies performed in
Nordic countries as well as Italy, showed that increased levels of chromosome aberrations in lymphocytes
can be used to predict cancer risk in humans. One may conclude that a dose of ionising radiation sufficient
to produce a certain level of cell damage increases production of antioxidants and repair enzymes that
decrease either the frequency of chromosome aberrations or the cancer risk. People in some areas of
Ramsar, a city in northern Iran, receive an annual radiation dose from background radiation that is more
than five times higher than the 20 mSv. Yr-1 that is permitted for radiation workers. Inhabitants of Ramsar
have lived for many generations in these high background areas. If an annual radiation dose of a few
hundred mSv is detrimental to health, causing genetic abnormalities or an increased risk of cancer, it
should be evident in these people. The absorbed dose rate in some high background radiation areas of
Ramsar is approximately 55-200 times higher than that of the average global dose rate. It has been
reported that 3–8% of all cancers are caused by current levels of ionising radiation. If this estimation were
true, all the inhabitants of such an area with extraordinary elevated levels of natural radiation would have
died of cancer. Our cytogenetic studies show no significant differences between people in the high
background area compared to people in normal background areas. As there was no increased level of
chromosome aberrations, it may be predicted that the cancer incidence is not higher than in the
neighbouring areas with a normal background radiation level. Although there is not yet solid epidemiological
information, most local physicians in Ramsar report anecdotally that there is no increase in the incidence
rates of cancer or leukemia in their area. There are no data to indicate a significant increase of cancer
incidence in other high background radiation areas (HBRAs). Furthermore, several studies show a
significant decrease of cancer death rates in areas with high backgrounds. It can be concluded that
prolonged exposure to high levels of natural radiation possibly triggers processes such as the production of
antioxidants and repair enzymes, which decreases the frequency of chromosome aberrations and the
cancer incidence rate.
10.1504/06.7892
3.New findings in the very high natural radiation area of Ramsar, Iran
•
M. Ghiassi-Nejada, b,
•
M.M. Beitollahia,
•
N. Fallahiana,
•
M. Saghirzadehb
•
a
,
,
National Radiation Protection Department, Iranian Nuclear Regulatory Authority, Tehran, Iran
•
b
•
http://dx.doi.org/10.1016/j.ics.2004.11.087, How to Cite or Link Using DOI
Department of Biophysics, Tarbiat Modarres University, P.O. Box 14155-4838 Tehran, Iran
Abstract
Ramsar, a northern coastal city of Iran, has some high levels of natural radiation areas
(HLNRAs) as well as about 50 hot springs with low and high radium contents usually used for
medical treatment purposes. Different radiological measurements, as well as cytogenetical,
immunological and preliminary biological and epidemiological studies have already been
performed in this region. The purpose of this study is to review new findings in very high
background radiation areas of Ramsar, in order to identify information relevant to exposures in
these areas and the potential and known impacts of such exposures on public health, and also to
make recommendations for further studies. At present, there is no reliable radio-epidemiological
data regarding the incidence of cancer in HLNRAs of Ramsar. In this regard, more extensive
researches are invited, in particular on epidemiology and radiobiology as well as on internal dose
assessment.
4.Cancer risk due to exposure to high levels of natural radon in the
inhabitants of Ramsar, Iran
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S.M.J. Mortazavia,
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M. Ghiassi-Nejadb,
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M. Rezaieanc
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a
Medical Physics Department, School of Medicine, Rafsanjan University of Medical Sciences (RUMS), Rafsanjan, Iran
•
b
National Radiation Protection Department (NRPD), Iranian Nuclear Regulatory Authority (INRA), P.O. Box 14155-4494,
,
,
Tehran, Iran
•
c
•
http://dx.doi.org/10.1016/j.ics.2004.12.012, How to Cite or Link Using DOI
•
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Social Medicine Department, School of Medicine, Rafsanjan University of Medical Sciences (RUMS), Rafsanjan, Iran
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Abstract
Inhabitants of Ramsar, a city in northern Iran, are exposed to levels of natural radiation as high
as 55–200 times higher than the average global dose rate. Furthermore, radon levels in some
regions of Ramsar are up to 3700 Bq m−3. To assess the association between the radon
concentration and frequency of lung cancer, lung cancer patients recorded over the past 2 years
in eight districts of Ramsar with different levels of radon were studied. Data from the Ramsar
Health Network show that both crude lung cancer rate and adjusted lung cancer rate in one
district with the highest recorded levels of external radiation and radon concentration are lower
than those of the other seven districts. It can be concluded that lung cancer rate may show a
negative correlation with natural radon concentration.
Figures and tables from this article:
<img hspace="2" height="51" border="0" align="middle" width="125"
vspace="2" alt="Full-size image (24 K)" title="Full-size image (24 K)"
src="http://ars.els-cdn.com/content/image/1-s2.0-S0531513104018461-gr1.sml"
data-thumbsrc="http://ars.els-cdn.com/content/image/1-s2.0-S0531513104018461-gr1.sml"
data-fullsrc="http://ars.els-cdn.com/content/image/1-s2.0-S0531513104018461-gr1.jpg">
Fig. 1. Panel A. Ramsar is divided into eight health districts. Panel B. The highest lung cancer mortality rate
was in Galesh Mahaleeh, where the radon levels were normal. On the other hand, the lowest lung cancer
mortality rate was in Ramak, where the highest concentrations of radon in the dwellings were found.
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