TREE project, Challenges and Future Updates Radiation Protection of the Environment (Environment Agency Course, July 2015)

Funded through RATE programme by NERC, EA & RWM Ltd. Objective: to reduce uncertainty in estimating the risk, to humans and wildlife, associated with exposure to radioactivity and to reduce unnecessary conservatism in risk calculations

to go on Newsletter

Challenge – transfer

CR pragmatic, but ….. Highly variable No data for many wildlife-radionuclide combinations ICRP Pub-114

Alternative model?

Alternative model? Cs by genus Bottom 25 REML adjusted mean

Cs – freshwater fish R 2 =0.83; slope=0.98±0.04

Challenge – exposure assessment Current assumption used in estimating dose fit for purpose?

What will TREE do?  Current simplistic assumptions ignore how animals utilise their environment = conservative?

Challenge - effects

Chernobyl – radiation effects on invertebrates

Into context ERICA ‘no effect level’

Into context ERICA ‘no effect level’ ICRP ‘expect effects’

Into context ERICA ‘no effect level’ UK natural background ICRP ‘expect effects’

Into context ERICA ‘no effect level’ UK natural background ICRP ‘expect effects’ Terrestrial population ‘no-effect’

Japan butterflies  Butterfly larvae fed plants harvested from Fukushima evacuated area  LD 50 = 1.9 Bq (?!)

Japan butterflies  Butterfly larvae fed plants harvested from Fukushima evacuated area  LD 50 = 1.9 Bq (?!)  LD 50 equates to a maximum of c. 8µGy/h  Below ‘no-effect’ and in natural background range?

Japan butterflies  Butterfly larvae fed plants harvested from Fukushima evacuated area  LD 50 = 1.9 Bq (?!)  LD 50 equates to a maximum of c. 8µGy/h  Below ‘no-effect’ and in natural background range?  From previous studies LD 50 for sub-adults ≥ 1 Gy

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What isTREE doing?

Wildlife cameras – estimate abundance of medium-large mammals

Controlled laboratory and parallel field studies

Future updates of the ERICA Tool  Multi site/time period entry capability  Continue to maintain the Wildlife Transfer Database and update ERICA as appropriate  Revise dosimetry approach to be the same as that used by ICRP and IAEA in forthcoming publications?  Add noble gases?  Consider IAEA and ICRP developments

IAEA activities  Updating SRS-19 report:  Volume 3 will include non-human biota  Somethings different to ERICA:  Direct deposition to vegetation surface (and subsequent consumption) included  Dosimetry – all daughters addressed individually (no <10d rule)  CRs corrected for radioactive decay

ICRP activities  RAPs to representative organisms  RAPs update  Scenarios  Further guidance on application of DCRLs in existing and emergency exposure situations

Trip to Chernobyl?