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EAN NORM Workshop, Hasselt, November 2011
The fate and behaviour of
NORM with respect to
environmental protection
Boguslaw Michalik
Laboratory of Radiometry, Central Mining Institute, Katowice, POLAND
ICRP vs. protection of environment
„the level of safety required for the protection of all human
individuals is thought likely to protect other species,
although not necessarily individual members of those
species. The Commission therefore believes that if
man is adequately protected then other living
things are also likely to be sufficiently protected „
(ICRP, 1977, § 14).
ICRP vs. protection of environment
„The standard of environmental control needed to protect man to the degree
currently thought desirable will ensure that other species
are not put at risk. Occasionally, individual members of non-human species
might be harmed, but not to the extent of endangering whole species or
creating imbalance between species. At the present time, the
Commission concerns itself with mankind’s environment only with
regard to the transfer of radionuclides through the environment,
since this directly affects the radiological protection of man „
(ICRP, 1991, § 16).
In 2007 the Commission continues to believe
that this is likely to be the case… but
„…also believes that it is necessary to consider a
wider range of environmental situations,
irrespective of any human connection with them.”
(ICRP, 2007)
Trends in legislation
IAEA BSS: Safety Principle 7: People and the environment,
present and future, must be protected against
radiation risks
European Basic Safety Standards:
Chapter I: Subject matter and scope
The scope is broadened to include the exposure of space crew to cosmic
radiation, domestic exposure to radon gas in indoor air, external
exposure to gamma radiation from building materials, and
the protection of the environment beyond
environmental pathways leading to human exposure
environmental risk caused by NORM
Features of environmental impact of NORM residues:
physical appearance
source geometry, location and possible
dispersion models: typical NORM
repositories have the appearance of common
waste dumps and tend to have more in common
with ordinary industrial waste than with spent
nuclear fuel or dispensable radioactive sources;
total amount: NORM residues are usually
bulk materials, e.g. phosphogypsum, slag,
sediments, sometimes water;
ambient conditions: residues are usually in
direct contact with environment, it means that
they are exposed to meteorological conditions
(water and wind erosion) and unlimited access
by biota;
Frequently they are associated with other pollutants as heavy metals,
sulphates, hydrocarbons.
Features of environmental impact of NORM residues:
radionuclides fractionation
238U
decay chain
Remain in native rock
U -238
Th -234
Remain in water or
Remain in air accumulates in sediment
Pa -234
U -234
Th -230
Leaching
Ra -226
Rn -222
exhalation
Po -218
precipitation
exhalation
Rn -222
Po -218
Pb -214
Pb -214
Bi -214
Bi -214
Po -214
Po -214
Pb -210
Pb -210
Bi -210
deposition
Leaching
deposition Bi -210
Po -210
Pb -206
bioaccumulation
Pb-210
anthropogenic
bioaccumulation
Po -210
Po -210
Pb -206
Pb -206
Features of environmental impact of NORM residues:
radionuclides fractionation
232Th
decay chain
Remain in water or
accumulates sediment
Remain in native rock
Th -232
Leaching
Ra -228
precipitation
Ac -228
precipitation
Th -228
Ra -224
Leaching
Leaching
Th -228
Ra -224
Rn -220
Rn -220
Po -216
Po -216
Pb -212
Pb -212
Bi -212
Bi -212
Po -212
Po -212
Tl -208
Tl -208
Pb -208
Pb -208
Features of environmental impact of NORM residues:
activity concentration evolution
226Ra
+
228Ra
210Pb
222Rn
228Th
+
210Bi
and short lived progeny
and short lived progeny
+
210Po
Total
228Ra
decay chain
Total 226Ra decay chain
Total natural radionuclides suite
Features of environmental impact of NORM residues:
alpha particles within uranium decay series
238
U
234
4.47••109yea
rt
Pa
234m
U
2.45••105yea
r
99.37
%230
Th
0.63%
4
1.17min.
234
Th
24.1day
8••10 year
234
Pa
6.7hour
226
Ra
1600
year
222
Rn
218
3.823day
218
At
1.75sekundy
218
Po
3.05min.
214
Pb
0.1%
0.03% 99.9%
99.97
%
26.8min.
Rn
0.019sec.
214
214
Po
210
1.64••10-4sec
Bi
210
99.96
19.7min.
%210
Pb
0.04%
Bi
5.01day
Tl
1.32min.
99.99995
%
5••10-5%
22.3 year
210
Po
138.4day
206
Pb
stable
206
Tl
4.19min.
European Basic Safety Standards
• Article 76
• Environmental criteria
Member States shall include, in their legal framework for
radiation protection and in particular within the overall
system of human health protection, provision for the
radiation protection of non-human species in the
environment.
environment
This legal framework shall introduce environmental
criteria aiming to protect populations of vulnerable
or representative non-human species in the light of
their significance as part of the ecosystem. Where
appropriate, types of practices shall be identified for
which regulatory control is warranted in order to
implement the requirements of this legal framework
How to define the critical
effect on the
environment ?
How it should be
quantified ?
How provide a
reliable evidence that
environment in well
protected?
Occurrence of radionuclides
=
effect on environment
Knowing natural radionuclides activity concentration in particular
compartment of environment is by far too less to assess any
environmental effect ......
Environmental effects ????
an reductionistic approach:
Reflected in the concept of
„reference organism”
• early mortality
• morbidity
• reduced reproductive success
ICRP 2008: Environmental Protection – the Concept and Use of Reference Animals and Plants.
ICRP Publication 108
ECOLOGY & EVOLUTION
BIOCENOZIS
Carnivores
Herbivores
Primary production
BIOTOPE
ENERGY FLOW
ECOSYSTEM
Detritivores
Decomposers
Autotrophs
photoautotrophs
chemoautotrophs
ABIOTIC ENVIRONMENT
TIME - INFORMATION FLOW
Effects on biota
Interaction of
contaminants with living
matter takes place at the
cellular level
Cellular response is:
the first manifestation of harmful effects
Genetic test-systems can be applied for an early
and reliable displaying of the alterations in
ecosystems
What is the expected effect on environment ?
Effect on cellular level
Cytotoxic
Genotoxic
Organ or tissue
disorder
Gene disruption or
mutation
Whole organism
dysfunction
Phenotype disorder
Environment risk assessment procedure
radionuclides distinction
radionuclides bioavailability
radionuclides inventory
radionuclides transfer to biota
radionuclides migration
external dose
internal dose
effects:
one cell
on individuals
mortality
morbidity
on population
disadvantage/
advantage
on ecosystem
reduced reproductive
success
Conclusion
Advantages:
The assumption:
No observed effect at cellular level = no effect on biota at all
Is easy to defended and no one is able to challenge this,
Tests of genotoxicity and cytotoxicity when applied widely are justified
enough from economic point of view
Disadvantages:
The presence of other pollutants can blur the results of applied tests
Thank you for your attention
This article was prepared in frame of „PORANO” project supported
by a grant from Norway through the Norwegian Financial Mechanism