Atomic Energy Organization of Iran

1
Atomic Energy Organization of Iran Iran Nuclear
Regulatory Authority (INRA)
Ramsar the Radioactive Nature
Presented by Naser Rastkhah Head of INRA
2
Ramsar is a coastal city located in the north of
Iran . And is well known for highest level of
natural radiation among the worlds high levels of
natural radiation areas (HLNRAs) such as Kerala
in India, Yangjiang in China, Guarapariin in
Brazil , ). Since 1959 this area is recognized
as HLNRA and has been the subject of
environmental radioactivity and epidemiological
studies. Several national and international
research teams visited the area and curried our
research projects
3
An international conference on high levels of
Natural Radiation was held in Ramsar jointly with
WHO , UNEP and IAEA in 1990
4
The natural radiation in Ramsar is mainly due to
the transfer of the dissolved radium in water to
the ground surface through the hot springs. So
the natural gamma dose rate is high in some
areas. Outdoor gamma dose rate is dependent on
the distribution of hot spring residues including
Ra-226. In some places it is 22µGy/h at height of
1 m and 73µGy/h on the surface.
5
Hot Springs as a Source of Natural Radionuclide
in Ramsar Region

• There are more than 9 hot springs with different
  concentrations of Ra-226 in Ramsar which people
  believe that they do well for rheumatism,
  neurotic and muscular pains, and skin diseases.
• Inhabitants who live in some houses in this area
  receive annual doses as high as 132 mSv.
• Cytogenetic studies show no significant
  differences between people living in the high
  background radiation areas comparing to those
  living in normal background areas.

6
Radon concentration at many homes is higher
comparing to those homes constructed in normal
areas.
Location (Houses, Schools and Hotels) 222Rn Concentration (kBq/m3)
Indoors 3.1
Outdoors 0.5
7
Some homes constructed with the stones
containing high value of Ra-226 and having high
level of Radon-222 concentration (3kBq/M3)
8
Since 1996, High Natural Radiation Research
Center has been established in Ramsar to conduct
research projects on high natural background
radiation and epidemiological studies at the
national and international level. Some
laboratories such as radioecology, sample
preparation as well as dosimetry have been
established and equipped with the radiation
detection equipments.
9
equipments in use for Gamma dose measurement
Passive Method
Active Method
TL environmental Dosimeter (GR-200)
Proportional Gamma counter
10
Radon Diffusion Chamber
Passive Radon Measurements (in Air)
Detector -Lexan Polycarbonate
Electrochemical Etching
Condition -Solution 15 KOH40
C2H5OH45 H2O -Field Strength 32
kV/cm -Frequency 2 kHz -Temperature
25?C
11
Active Radon Measurements
AlphaGuard
Pylon AB-5
Measurement of dissolved Radon in water
12
A comprehensive action plan approved and
scheduled by INRA in 2008 which consisted of 4
projects a) Preparing the natural
radioactivity map of Ramsar including
measurement of gamma dose rate on the ground
surface, radionuclide content of the soil,
radium-226 and Rn-222 content of the drinking
water, Rn-222 concentration at homes following
standard protocols. b) To determine precisely the
exposure of people considering all pathways such
as inhalation, ingestion and external
exposure. c) To do a health surveillance programe
for the people living in the area considering
natural exposure. d) To provide guidelines and
solutions to the inhabitants to reduce their
exposure considering the social and economical
impacts.
13
The area of Ramsar is about 729.8 Km2. The
central and most populated area (Red line) was
selected for investigation and was divided to
2500 cells of dimension 50x50 m2. The gamma dose
rate was measured at 5 Cm and 100 Cm above the
ground using scintilation survey meter. Maximum,
minimum and average dose rate along with the
georaphical specification of the cells registered
for each cell.
14
Gamma dose rate measurement at 1 m above the
ground
15
Project a) was ended by 2012 and Gamma Dose map
of Ramsar at 1 meter above the ground was
prepared. This project shall be extended to cover
also the suburb of Ramsar
150 lt nSv/h 150 lt lt 300 300lt
lt600 600lt lt1000 1000lt
lt3000 3000lt lt6000 6000lt lt10000 10000lt
lt15000 gt15000
16
Project a) Gamma Dose map of Ramsar at 5 Cm
above the ground was
150 lt nSv/h 150 lt lt 300 300lt
lt600 600lt lt1000 1000lt
lt3000 3000lt lt6000 6000lt lt10000 10000lt
lt15000 gt15000
17
INRA in Corporation with the Road, Housing and
Urban Development Research Center approved the
Regulation for the protection of buildings agaist
the penetration of Radon gas to be implemented in
high natural radiation areas
18
More budget and investment is needed to complete
high natural background radiation research center
of Ramsar. All researchers and interested
research institutes and universities are highly
welcomed for defining and performing common
projects jointly with INRA as well as sponsorship
to equip laboratories
19
Thank you for your attention