TITRE DE LA PRESENTATION

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Towards a protection of species at the
population level derivation of PNEDR values by
modelling population responses to ionizing
radiations Emilie Lance, Frédéric Alonzo,
Jacqueline Garnier-Laplace
EMRAS Meeting, 26-27/01/2010, Vienna, Austria
Direction de lEnvironnement et de
lIntervention Service dEtude du Comportement
des Radionucléides dans les Ecosystèmes Laboratoir
e de Modélisation Environnementale
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Evaluation of environmental risk from ionizing
radiations
Background on ERICA and PROTECT recommendation

• IAEA standards for environmental
  radioprotection
• ICRP recommendation of similar method than for
  chemical substances, 2005 Sept

European projects

• FASSET (2001-2004) 5th PCRD
• ERICA (2004-2007) 6th PCRD
• PROTECT (2006-2008) 6th PCRD

Risk assessment screening dose or dose rate,
benchmarks for the protection of wild species
againts impact of ionizing radiations.
EMRAS Meeting, 2010-01-26/27, Vienna, Austria
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FREDERICA database effects of ionizing
radiations on non-human organisms
Background on ERICA and PROTECT data set

• Ecotoxicity data
• 25000 couples (dose or dose rate, effect) from
  1040 references
• 16 pseudo-taxonomic groups
• 3 ecosystems

EMRAS Meeting, 2010-01-26/27, Vienna, Austria
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Which data for the derivation of benchmarks ?
Background on ERICA and PROTECT data set

• Effects observed at the individual and
  sub-individual level

4 categories - (1) morbidity growth rate,
immune system, behavior (impact on
the central nervous system),
- (2) mortality also mutations that
affect life expectancy
- (3) reproductive capacity fertility,
fecundity, hatching/survival of embryos
- (4) mutations of
somatic and reproductive cells

• On the first hand, data on chronic exposure to
  gamma radiation, external radiation exposure
  (µGy.h-1)

EMRAS Meeting, 2010-01-26/27, Vienna, Austria
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Derivation of criteria for the protection of
populations
Background on ERICA and PROTECT method

• Radiotoxicity data relative to life-history
  traits (protection of the population)
• Dose (rate)-effect relationships critical data,
  EDR10 (dose rate inducing 10 of effect on the
  endpoint in comparison with controls)
• For a given species, if an EDR10 is available
  for several endpoints, the most sensitive is
  selected

EMRAS Meeting, 2010-01-26/27, Vienna, Austria
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Derivation of criteria for the protection of
populations
Background on ERICA and PROTECT method

• Extrapolation model  Species Sensitivity
  Distribution  (SSD)
• HDR5 Dose rate protecting 95 of species (95
  are affected at maximum 10 of effect in
  comparison with controls)

Garnier-Laplace et al. (2008)
HDR5 / safety factor PNEDR (Predicted No Effect
Dose Rate)
EMRAS Meeting, 2010-01-26/27, Vienna, Austria
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Background on ERICA and PROTECT possible
improvements
Sensitivity of the population growth rate to
impact on individuals endpoints
Ecosystem level
Community level
Population level
Ecotoxicity data at the individual level
Whole organism level
Life history strategies
Physiological level
Life-history traits survival, growth, fecundity
impact
Biochemical level
Time scale
EMRAS Meeting, 2010-01-26/27, Vienna, Austria
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Background on ERICA and PROTECT possible
improvements
Population dynamic depending on survival and
reproduction in each life stage
1) Population structured per age classes
2) Cohorts vary over time depending on survival
and fecundity
? Modeling population size in number
? Determination of population growth rate
EMRAS Meeting, 2010-01-26/27, Vienna, Austria
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Background on ERICA and PROTECT possible
improvements
Comparison of population sensitivity to changes
in different endpoints and different species
Alonzo et al., 2008
Delay in population growth (relative to
generation time T)
T 10 days
T 12 weeks
Individual level effect
? Sensitivity of population depends on individual
endpoints

• Sensitivity of population depends on life
  history strategy of different species

EMRAS Meeting, 2010-01-26/27, Vienna, Austria
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Toward a protection of species at the population
level
Method and required data a first theoretical step
2nd step utilization of data from FREDERICA

Simulation of population dynamics of each species
in control conditions and with 0 to 100
decrease in each life-history trait

Dose rate ?

• 10 on the
• population
• growth rate

modélisation
Pop-EDR10 Dose rate inducing 10 decrease in
population growth rate
EMRAS Meeting, 2010-01-26/27, Vienna, Austria
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Toward a protection of species at the population
level
Derivation of benchmarks

• Extrapolation model  Species Sensitivity
  Distribution  (SSD) with pop-EDR10 at the
  population level
• New HDR5 Dose rate protecting population
  dynamics for 95 of species (decrease in
  population growth rate of less than 10 in
  comparison with controls)

Pop-EDR10
EMRAS Meeting, 2010-01-26/27, Vienna, Austria
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Thanks for your attention
// more informations on European program
ERICA Risques des substances radioactives pour
lenvironnement http//www.erica-project.org Euro
pean program PROTECT Protection of the
environment from ionising radiation in a
regulatory context http//www.ceh.ac.uk/protect/
FREDERICA Radiation Effects Database
http//87.84.223.229/fred/mainpage.asp http//w
ww.irsn.org/ CIPR http//www.icrp.org NEA
http//www.nea.fr
EMRAS Meeting, 2010-01-26/27, Vienna, Austria