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Ramsar as a Very High Background Radiation Area
I received the follwoing from my very good friend, Dr. John Cameron.
I am posting this on Radsafe, since it is extremely interesting, and,
timely based on recent discussions:
-----------
Sandy, I think there should be a web page to make articles like this
available to a wider audience. Any suggestions? John
You may also be interested in the following material I just sent to my
RSH colleagues.
Dear Colleagues, I thought some of you may be unaware (as I was) of perhaps
the highest natural background radiation in the world. If you want the
author's e-mail address, I have it somewhere. He (I believe) started the
interesting web page while in Japan located at
http://www.angelfire.com/mo/radioadaptive which gives much information on
hormesis and related areas. Best wishes, John
Ramsar as a Very High Background Radiation Area and the Radiation
Protection Policy of the Iranian Government
S. Mohammad Javad Mortazavi2
Rafsanjan University of Medical Sciences, Rafsanjan, Iran
Ramsar a beautiful city located in north Iran; has the highest level of
natural radioactivity studied so far. The radioactivity of the area is due
to Ra-226 and its decay products, which have been brought up to earth
surface by the water of warm springs. The radiation rate in these areas was
first supposed to range from 0.08 mR/h to 5.5 mR/h; but recent studies
indicated that the dose rate is up to 9 mR/h. The effective dose
equivalents in the high background radiation areas (HBRAs) of Ramsar in
particular in Talesh Mahalleh, are few times higher than the dose limits
for radiation workers. The basic aim of this paper is to answer the
question on whether populations living in these areas should be relocated.
Despite the fact that cytogenetic studies have shown some significant
differences between the results of the exposed group and the control, the
public is still appreciate enjoying the beautiful natural environment,
especially using the spas.Å@The persons who live in the HBR areas of Ramsar
do not have any increased cancer, or leukemias. Obviously this may be
attributed to the difference in individual susceptibilities to radiation
exposure, so at present time we are conducting an experiment to assess the
possible existense of a radioadaptive response in the inhabitants of these
areas. On the other hand there are many other areas with a high level of
background radiation in the world, and epidemiological studies have
indicated that natural radiation in these areas is not harmful for the
inhabitants. It can be concluded that the health effects of natural
radiation are seperated by a threshold from the harm of large doses. This
threshold seems to be much higher than the greatest level of natural
radiation (e.g. lifetime doses up to 3 Sv in Ramsar). Despite the fact that
more research is needed to evaluate the biological effects of high levels
of natural radiation in Ramsar, the Iranian government doesn't need to
evacuate this city.
Following is a proposal to do research on the population of his area.
Atomic Energy Organization of Iran (AEOI)
National Radiation Protection Department (NRPD)
RRA Project
The Search for Raioadaptation in the Inhabiatants of the High Background
Radiation Areas (HBRAs) of Ramsar
Members of the research team:
1. Mehdi Ghiasee Nejad, Ph.D (Chairman of the National Radiation Protection
Department (NRPD) of the Atomic Energy Organization of Iran (AEOI).
2. S. M. Javad Mortazavi, Ph.D (Assistant professor of Medical Physics of
Rafsanjan University of Medical Sciences).
3. Masood Momen Beitollahi, M.Sc (Vice-chairman of the National Radiation
Protection Department (NRPD) of the Atomic Energy Organization of Iran
(AEOI).
4. Reza Gholi Asaiee, M.Sc (Director of the Medical Section at National
Radiation Protection Department (NRPD) of the Atomic Energy Organization of
Iran (AEOI).
5. Ahmad Heidari, B.Sc (Scientific member of the Medical Section at
National Radiation Protection Department (NRPD) of the Atomic Energy
Organization of Iran (AEOI).
6. Farideh Zakeri, M.Sc (Scientific member of the Medical Section at
National Radiation Protection Department (NRPD) of the Atomic Energy
Organization of Iran (AEOI).
7. Roshan Varzegar, B.Sc (Scientific member of the Medical Section at
National Radiation Protection Department (NRPD) of the Atomic Energy
Organization of Iran (AEOI).
1. Background Information
1.1. Ramsar as a HBRA
Ramsar a very beautiful northern city of Iran located at the foot of the
Alburz mountains and overlooking the Caspian Sea, has some high background
radiation areas (HBRAs). Talesh Mahalle, Chaparsar and Ramak are among the
most well known HBRAs in Ramsar. Furthermore, there are more than 50 hot
springs with different concentrations of radium in this city. These springs
are usually used as spas by the residents. According to the results of the
surveys performed by the Atomic Energy Organization of Iran (AEOI), the
radioactivity seems to be first due to the mineral water springs passing
through streams leaving radioactivity residues filtered by the soil and
second due to some travertine deposits having a thorium content more than
that of uranium (Sohrabi 1990). The results of environmental gamma
exposures measured in different areas of Ramsar, both indoor and outdoor
ranged from 0.05 to 9 mR/h. The dose received by the individuals monitored
in the area, ranged up to 132 mSv/y. It can be concluded that the effective
dose equivalents of inhibitants of HBRAs of Ramsar can be few times higher
than the accepted dose limits for radiation workers (Sohrabi 1990).
Considering these data, it can be claimed that Ramsar has the highest level
of natural radioactivity studied so far (Sohrabi 1990)
1.2. Radioadaptation
It is now clearly known that ionizing radiation and a variety of DNA
damaging stresses such as UV, alkylating or oxidizing agents and heat can
induce responses which are related to repair of the initial damage. The
results of many studies indicated that when cells are exposed to low doses
of these agents, they often become less sensitive to the harmful effects of
a subsequent higher dose. This type of induced repair is called adaptive
response (AR). The induction of adaptive response was first reported by
Samson and Carins (1977). Using Escherichia Coli, they showed that
bacterial cells which had been exposed to low levels of alkylating agents,
became less susceptible to the subsequent high doses of the same agent or
other similar compounds.
Later it was first found that in vitro pretreatment of human lymphocytes
with tritiated thymidine, caused these cells become less susceptible to
cytogenetic damage of a subsequent high dose X-ray (Olivieri et al. 1984).
They reported that surprisingly the frequency of chromatid aberrations were
up to 50% less than expected. Since then, many reports have been world wide
published. These articles demonstrated the induction of radioadaptive
response (RAR) in cultured human lymphocytes, embryonic and HeLa cells,
occupationally exposed persons, residents of contaminated areas by
Chernobyl accident, cultured animal lymphocytes and in vivo studies with
animals. Radioadaptive response has been found to be dependent upon many
factors including adapting dose, dose rate, cell cycle, pH, and culture
condition. The induction of radioadaptive response has been observed for
several end-points including chromosomos aberrations, micronuclei
formation, sister chromatid exchange and mutation induction at the HPRT
locus.
1.3. High Levels of Background Radation as an Adapting Dose
Epidemiological evidences have indicated that the natural radiation in
HBRAs is not harmful to residents. Furthermore, cancer mortality rate is
significantly lower in the high background areas than in the control areas
(Ikushima 1999). This is one of typical examples of radiation hormesis, but
If we want to claim that high background radiation act as an adapting dose,
we should study the radio-resistance of residents in these areas after
receiving a high dose (Ikushima 1999).
2. Objectives
The primary project goals are to
… Assess the possible induction of radioadaptive response (RAR) in
inhabitants of HBRAs of Ramsar.
… Determine the magnitude of RAR in responders.
… Determine the role of the annual effective dose on the magnitude of RAR
in responders.
3. Proposed Research Plan
Considering published data on the average annual effective dose of
inhabitants of HBRAs of Ramsar, the blood donors will be selected from 3
different HBRAs (with different levels of background radiation) and a
normal background radiation area (NBRA) with similar socioecologic
condition.Blood samples will be irradiated with different doses og Gamma
rays (0, 1.5, 2, 3 Gy). Using chromosome aberration study, MN assay and
FISH as the main endpoints, the possible induction of RAR in inhabitants of
HBRAS will be studied.
4. Project Timeline
Preliminary experiments 4 months
Cytogenetic studies 12 months
Data analysis 2 months
Total 18 months
5. Funding for the Project
The National Radiation Protection Department (NRPD) of the Atomic Energy
Organization of Iran (AEOI) will provide the initial funds. Rafsanjan
University of Medical Sciences will also provide available support for the
project.
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Sandy Perle Tel:(714) 545-0100 / (800) 548-5100
Director, Technical Extension 2306
ICN Worldwide Dosimetry Division Fax:(714) 668-3149
ICN Biomedicals, Inc. E-Mail: sandyfl@earthlink.net
ICN Plaza, 3300 Hyland Avenue E-Mail: sperle@icnpharm.com
Costa Mesa, CA 92626
Personal Website: http://www.geocities.com/capecanaveral/1205
ICN Worldwide Dosimetry Website: http://www.dosimetry.com
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