Radiation Protection of the Environment

Dr Mike Wood

5th International Summer School, JRC-Ispra, 9-13 September 2013

Learning outcomes

By the end of this lecture you should be able to:

1. Identify drivers for environmental radiation protection (ERP)

2. Describe a generic framework for environmental radiation risk assessment (ERRA)

3. Discuss strengths and limitations of common ERRA approaches

4. Identify challenges in ERRA in the context of waste management and decommissioning

5. Locate relevant sources of information on ERP

A wise Chinese dude once said...

I hear and I forget. I see and I remember. I do and I understand.

Confucius

Learning outcomes

By the end of this lecture you should be able to:

1. Identify drivers for environmental radiation protection (ERP)

2. Describe a generic framework for environmental radiation risk assessment (ERRA)

3. Discuss strengths and limitations of common ERRA approaches

4. Identify challenges in ERRA in the context of waste management and decommissioning

5. Locate relevant sources of information on ERP

Why is ERP required?

‘Although the principal objective of radiation protection is the achievement and maintenance of appropriately safe conditions for activities involving human exposure, the level of safety required for the protection of all human individuals is thought likely to be adequate to protect other species, although not necessarily individual members of these species. The Commission therefore believes that if man is adequately protected then other living things are also likely to be sufficiently protected.’

ICRP (1977)

Why is ERP required?

‘Although the principal objective of radiation protection is the achievement and maintenance of appropriately safe conditions for activities involving human exposure, the level of safety required for the protection of all human individuals is thought likely to be adequate to protect other species, although not necessarily individual members of these species. The Commission therefore believes that if man is adequately protected then other living things are also likely to be sufficiently protected.’

ICRP (1977)

Why is ERP required?

‘Although the principal objective of radiation protection is the achievement and maintenance of appropriately safe conditions for activities involving human exposure, the level of safety required for the protection of all human individuals is thought likely to be adequate to protect other species, although not necessarily individual members of these species. The Commission therefore believes that if man is adequately protected then other living things are also likely to be sufficiently protected.’

ICRP (1977)

Why is ERP required?

‘Although the principal objective of radiation protection is the achievement and maintenance of appropriately safe conditions for activities involving human exposure, the level of safety required for the protection of all human individuals is thought likely to be adequate to protect other species, although not necessarily individual members of these species. The Commission therefore believes that if man is adequately protected then other living things are also likely to be sufficiently protected.’

ICRP (1977)

Logical (man as most radiosensitive organism)

SOURCE: UNSCEAR, 1996

Why is ERP required?

‘Although the principal objective of radiation protection is the achievement and maintenance of appropriately safe conditions for activities involving human exposure, the level of safety required for the protection of all human individuals is thought likely to be adequate to protect other species, although not necessarily individual members of these species. The Commission therefore believes that if man is adequately protected then other living things are also likely to be sufficiently protected.’

ICRP (1977)

Logical (man as most radiosensitive organism)

BUT increasing calls to demonstrate adequate

protection of the environment per se

Recognised by ICRP in 2003, environment

explicitly considered in ICRP 2007

recommendations.....

...and many others

• E.g. JOINT CONVENTION ON THE SAFETY OF SPENT FUEL MANAGEMENT AND ON THE SAFETY OF RADIOACTIVE WASTE MANAGEMENT

– Ratified June 2012

– One of the aims: To ensure that there are effective defences against potential hazards so that individuals, society and the environment are protected now and in the future

National and International legislation

• EC, 1979. EC Birds Directive 79/409/EEC

– UK Parliament, 1981. Wildlife and Countryside Act

• EC, 1992. EC Habitats Directive 92/43/EEC

– UK Parliament, 1994. Conservation (Natural Habitats) Regulations

• Requires demonstration of protection of designated sites and species from ‘hazardous substances’

– Interpreted to include ionising radiation

• Environmental radiation protection assessments are required!

Public perception:

Public perception: Radioactivity is good!

Radium Water Jar (late 1920s, early 1930s)

Doramad Radioactive Toothpaste (ca. 1940-1945)

http://www.orau.org/ptp/collection/quackcures/quackcures.htm

Degnen's Radio-Active Eye Applicator (1915-1930)

http://www.orau.org/ptp/collection/quackcures/quackcures.htm

Public perception: Radioactivity is good!

http://www.orau.org/ptp/collection/quackcures/quackcures.htm

Public perception: Radioactivity is good!

Public perception: Radioactivity is bad!

• Manhattan project

• Hiroshima & Nagasaki

• Windscale

• Three Mile Island

• Chernobyl

• Litveneko

BUT climate change and energy shortage is worse!

International nuclear renaissance

The Fukushima Factor

• Impact on the nuclear renaissance?

– Some political U-turns (e.g. Germany)

– Many other nations continue to pursue nuclear energy

• Heightened (and renewed) public awareness of risks

• Accountable to increasingly ‘educated’ public

• ....Need environmental radiation protection models that are

– Fit-for-purpose

– Stand up to scientific & public scrutiny (stakeholder acceptance)

Points to note

• ERP primarily a regulatory response (linked to public perception)

• Does not reflect any expectation that regulated discharges will result in significant environmental impacts (Higley & Alexakhin, 2004)

Learning outcomes

By the end of this lecture you should be able to:

1. Identify drivers for environmental radiation protection (ERP)

2. Describe a generic framework for environmental radiation risk assessment (ERRA)

3. Discuss strengths and limitations of common ERRA approaches

4. Identify challenges in ERRA in the context of waste management and decommissioning

5. Locate relevant sources of information on ERP

A Generic Framework for Environmental Radiation Risk

Assessment (ERRA)

• Reference organisms

“a series of entities that provide a basis for the estimation of radiation dose rate to a range of organisms which are typical, or representative, of a contaminated environment. These estimates, in turn, would provide a basis for assessing the likelihood and degree of radiation effects” (ERICA)

• Target of protection = Population

A Generic Framework

for Environmental Radiation Risk Assessment

(ERRA)

A Generic Framework

for Environmental Radiation Risk Assessment

(ERRA)

Stakeholder input

Media activity concentrations

A Generic Framework

for Environmental Radiation Risk Assessment

(ERRA)

Measurement

Measurement

BUT.....

– Protected

– Ethics

• Instantaneous equilibrium

Prediction (Concentration Ratio)

) dry weight kg (Bq soilin ion concentratActivity

ht)fresh weig kg (Bq organism in wholeion concentratActivity CR

1-

-1

soil-wo

)l (Bqin water ion concentratActivity

ht)fresh weig kg (Bq organism in wholeion concentratActivity CR

1-

-1

water-wo

Other parameters to define ‘reference organisms’

• Occupancy factor = Proportion of time spent in different exposure geometries

• Dimensions

– Used in dosimetry

– Assume homogenous contamination

– Ellipsoids

Other parameters to define ‘reference organisms’

• Occupancy factor = Proportion of time spent in different exposure geometries

• Dimensions

– Used in dosimetry

– Assume homogenous contamination

– Ellipsoids

A Generic Framework

for Environmental Radiation Risk Assessment

(ERRA)

Putting results in context

• Screening dose rate recommended by EC Projects [ERICA & PROTECT] = 10 µGy h-1

– Population level effects < 10 µGy h-1 = not of concern

– 10 µGy h-1 is NOT a limit = Part of a Tiered Approach

• No internationally agreed limits

• FREDERICA Database (http://www.frederica-online.org/mainpage.asp)

• ICRP Derived Consideration Reference Levels (DCRLs)

‘a band of dose rates within which there is likely to be some chance of deleterious effects of ionising radiation occurring to individuals’ = a point of reference

Some software Tools....

R&D128/SP1a

ERICA

RESRAD-BIOTA

Learning outcomes

By the end of this lecture you should be able to:

1. Identify drivers for environmental radiation protection (ERP)

2. Describe a generic framework for environmental radiation risk assessment (ERRA)

3. Discuss strengths and limitations of common ERRA approaches

4. Identify challenges in ERRA in the context of waste management and decommissioning

5. Locate relevant sources of information on ERP

Strengths and Weaknesses

• Pragmatic – allows ERP to be operationalised through ERRA

• Resource efficient

• International consensus on generic framework

• Software tools freely available

• Uncertainty communicable

• Realism

• Homogenous contamination

• Whole-body dose rate

• Equilibrium (not accident)

• No international consensus on ‘screening dose rates’, ‘action levels’ or ‘limits’

• Software tools freely available (open to misuse)

• Uncertainty (esp CRs)

Strengths and Weaknesses

• Pragmatic – allows ERP to be operationalised through ERRA

• International consensus on generic framework

• Software tools freely available

• Uncertainty communicable

• Realism

• Homogenous contamination

• Whole-body dose rate

• Equilibrium (not accident)

• No international consensus on ‘screening dose rates’, ‘action levels’ or ‘limits’

• Software tools freely available (open to misuse)

• Uncertainty (esp CRs)

Scale of the issue

• Many

– radionuclide – reference organism combinations

– radionuclide transfer pathways

• IAEA EMRAS II WG 5: TRS Handbook on Radionuclide Transfer to Wildlife

• Online database to collate CR data

– Freely available!

– 50,000 entries • 87,000 CRwo-media values

• 520 data sources

http://www.wildlifetransferdatabase.org/

Freshwater

Radionuclide Fish Vascular plant Mollusc Reptile Algae Phytoplankton Crustacean Insect larvae Insect Zooplankton Mammal Amphibian

Cs

Sr

Am Cm

Pu

Ra

Ce

Co

Mn

U

Pb

Cd

Po

Sb

Se

I

Ni

Th

Zr

Eu

Ru

Cl

P

Np S

Tc

Te

Ag

Nb

n≤10 n>10<20 n>20<100 n≥100

Slide source: Brenda Howard, CEH

But do we need CRs for everything?

• Which knowledge gaps are ‘important’?

– Likely pathways

– Relevant organisms

– Dose contributors

• Prioritise research to reduce uncertainty

– MODARIA

– IUR TG on non-lethal methods

Learning outcomes

By the end of this lecture you should be able to:

1. Identify drivers for environmental radiation protection (ERP)

2. Describe a generic framework for environmental radiation risk assessment (ERRA)

3. Discuss strengths and limitations of common ERRA approaches

4. Identify challenges in ERRA in the context of waste management and decommissioning

5. Locate relevant sources of information on ERP

Challenges

• Time horizons

– Stakeholder perceptions aren’t static • So neither are risk judgements

– Predicting future environments

Challenges

• Time horizons

– Stakeholder perceptions aren’t static • So neither are risk judgements

– Predicting future environments

• Harmonise with human assessments

Surely we can find commonalities!?!

Challenges

• Time horizons

– Stakeholder perceptions aren’t static • So neither are risk judgements

– Predicting future environments

• Harmonise with human assessments

• Multiple stressors

Learning outcomes

By the end of this lecture you should be able to:

1. Identify drivers for environmental radiation protection (ERP)

2. Describe a generic framework for environmental radiation risk assessment (ERRA)

3. Discuss strengths and limitations of common ERRA approaches

4. Identify challenges in ERRA in the context of waste management and decommissioning

5. Locate relevant sources of information on ERP

Some sources of information...

• ICRP

– Committee 5 on Protection of the Environment (http://www.icrp.org/icrp_group.asp?id=12)

• IAEA

– EMRAS/EMRAS II (http://www-ns.iaea.org/projects/emras/emras2/default.asp?s=8&l=63)

– MODARIA (http://www-ns.iaea.org/projects/modaria/default.asp?s=8&l=116)

• EC

– STAR (https://wiki.ceh.ac.uk/display/star/The+Radioecology+Exchange)

• BIOPROTA (http://www.bioprota.com/)

Some sources of information...

Some sources of information...

m.d.wood@salford.ac.uk

Learning outcomes

By the end of this lecture you should be able to:

1. Identify drivers for environmental radiation protection (ERP)

2. Describe a generic framework for environmental radiation risk assessment (ERRA)

3. Discuss strengths and limitations of common ERRA approaches

4. Identify challenges in ERRA in the context of waste management and decommissioning

5. Locate relevant sources of information on ERP

Learning outcomes

By the end of this lecture you should be able to:

1. Identify drivers for environmental radiation protection (ERP)

2. Describe a generic framework for environmental radiation risk assessment (ERRA)

3. Discuss strengths and limitations of common ERRA approaches

4. Identify challenges in ERRA in the context of waste management and decommissioning

5. Locate relevant sources of information on ERP

Learning outcomes

By the end of this lecture you should be able to:

1. Identify drivers for environmental radiation protection (ERP)

2. Describe a generic framework for environmental radiation risk assessment (ERRA)

3. Discuss strengths and limitations of common ERRA approaches

4. Identify challenges in ERRA in the context of waste management and decommissioning

5. Locate relevant sources of information on ERP

Learning outcomes

By the end of this lecture you should be able to:

1. Identify drivers for environmental radiation protection (ERP)

2. Describe a generic framework for environmental radiation risk assessment (ERRA)

3. Discuss strengths and limitations of common ERRA approaches

4. Identify challenges in ERRA in the context of waste management and decommissioning

5. Locate relevant sources of information on ERP

Learning outcomes

By the end of this lecture you should be able to:

1. Identify drivers for environmental radiation protection (ERP)

2. Describe a generic framework for environmental radiation risk assessment (ERRA)

3. Discuss strengths and limitations of common ERRA approaches

4. Identify challenges in ERRA in the context of waste management and decommissioning

5. Locate relevant sources of information on ERP

Learning outcomes

By the end of this lecture you should be able to:

1. Identify drivers for environmental radiation protection (ERP)

2. Describe a generic framework for environmental radiation risk assessment (ERRA)

3. Discuss strengths and limitations of common ERRA approaches

4. Identify challenges in ERRA in the context of waste management and decommissioning

5. Locate relevant sources of information on ERP

Questions???