Radiation can be carried long distances by marine currents, concentrated in sediments, and carried in sea spray 16km or more inland, writes Tim Deere-Jones. So Fukushima poses a hazard to coastal populations and any who eat produce from their farms. So what are the Japanese Government and IAEA doing? Ignoring the problem, and failing to gather data.
The strategy it has adopted, with the support of the IAEA, consistently ignores the latest evidence about the way marine radioactivity behaves in inshore marine environments and the potential radiological risks to coastal populations.
This strategy is based on a flawed hypothesis, developed by the nuclear industry through the late 1940s and early 1950s, when both oceanography and the study of the behaviour and fate of radioactivity in marine environments were in their absolute infancy.
As a result, the principal conclusions on the marine impact of the Fukushima event put forward in recent reports from the IAEA, the Government of Japan and it’s relevant agencies, minimise the environmental and public health negatives and emphasise a range of hypothetical ‘positives’.
This is a major flaw because the empirical evidence from ‘non-aligned’ research in the UK is that coastal communities are subjected to highly enriched doses of marine radioactivity through pathways of exposure, and from environmental parameters, which will not be analysed and researched under current Fukushima monitoring plans.[…]
Review also confirms a major focus on short lived Caesium isotopes, with a secondary focus on a limited number of other beta emitters, also with short half lives. By contrast, there is an almost total absence of any work on the long lived alpha emitters, which have been only sparsely studied in the relatively small sea area immediately adjacent to the Fukushima outfalls.
In the context of the high risks to be incurred from internal doses of such alpha emitters, and their well-attested transportability in marine environments, this is an astonishing omission.
The nuclear industry hypothesis proposed that fully soluble radioactivity, such as Caesium, mixes very well in the marine water body and thus is dispersed and diluted to infinity or background. On page 39: of Technical Volume 4/5. of the IAEAs 2015 ‘Fukushima Daiichi Accident Report’, the IAEA repeat this assertion.
Radiation is concentrated in marine sediments
However, empirical evidence from UK research (all cited in my testimony to the House of Commons) powerfully refutes this claim and demonstrates that soluble radioactivity is transported over hundreds of kilometres in sea water and then re-concentrated (relative to ambient sea water) in both pore-water and fine sediments deposited out of the water column and into coastal mud flats and salt marsh.
There is a wealth of empirical field data to show that, wherever investigated, sea borne Caesium transfers across the UK surf line by a variety of mechanisms including coastal flooding, and also marine aerosols and sea sprays, where Caesium may undergo enrichment relative to seawater.
The nuclear hypothesis proposed that insoluble radioactivity, like alpha emitting Plutonium and Americium (which partition out of the water column by ad-sorbing to the outer surface of suspended sedimentary particles), becomes attached to suspended particles in the marine water column, deposits out on the sea bed near the end of discharge pipelines and there remains immobilised and sequestered from human beings.
UK empirical evidence also refutes this claim and demonstrates that such ‘insoluble radioactivity’ is also highly mobile, can travel 100s of kms in marine water columns, deposit out in inshore mud flats and salt marshes where it can become enriched by a factor of ten.
In marine aerosols and sea spray it may be enriched by up to factor of 400 (relative to ambient seawater) and, wherever investigated, transfers across the surf line and into the coastal, terrestrial zone.
On the basis of their flawed original hypothesis it has become an article of faith for the nuclear industry and the IAEA to insist that dietary doses of marine radioactivity are only received by sea food consumers (seaweed, shell fish, crustaceans and fin fish). Thus the Japanese Government / IAEA plan sets out a strategy for the monitoring of such sea foods, but not to monitor other forms of dietary consumption of marine radioactivity.
Transported hundreds of kilometres, reaches at least 16km inland
UK empirical evidence refutes this claim: and has demonstrated that dietary doses of marine radioactivity are also received from coastal, terrestrial foodstuffs (animal, arable and horticultural products and wild foods) grown and harvested in coastal areas (16km or more inland) which are subjected to sea to land transfer mechanisms from sediment rich, inshore waters contaminated by liquid nuclear waste discharges, and facing prevailing onshore winds.
UK research shows that such mechanisms can occur at least 200km (by sea) distant from the point source of radioactivity, and that populations living in such areas are exposed to terrestrial food stuffs which can deliver a higher marine radioactivity (dietary) dose than do locally harvested sea foods.
Analysis of this research has shown that coastal populations ‘distant’ from a discharge point of ‘liquid’ radioactive wastes, may receive higher doses of marine radioactivity through their local terrestrial diet, than populations living adjacent to liquid radioactive waste point sources receive through their local sea foods.
UK research clearly shows that coastal zone populations are exposed to doses of marine radioactivity under the following set of environmental parameters:
resident in coastal zones up to at least 200kms downstream of a source of liquid radioactive discharges to sea
resident in coastal zones adjacent to coastal waters with high suspended sediment loadings
resident in coastal zones adjacent to extensive fine sediment inter tidal/sub tidal sediment deposits (salt marsh, mud flats etc)
resident in coastal zones subject to prevailing onshore winds and storm or tidal conditions generating marine aerosols, sea spray and coastal inundation
resident in coastal zones where such parameters (A to D above) have, elsewhere, been shown to enable/facilitate the penetration of marine radioactivity for across the shoreline and up to 10 miles inland from the coast.