Observations on the redistribution of plutonium and americium in the Irish Sea sediments, 1978 to 1996: concentrations and inventories

Transport of plutonium (239/240Pu) and caesium (137Cs) in the Irish Sea: comparison between observations and results from sediment and contaminant transport modelling

“…Both observations (Kershaw et al, 1999) and model results present similar and consistent patterns, with net loss from along the Cumbrian coast and gains in Liverpool Bay and the western Irish Sea. The increase in Liverpool Bay is somewhat patchier, and in places significantly smaller in the model than observed.…”

Diagenetic reactivity of the plutonium in marine anoxic sediments (Cumbrian mud patch - eastern Irish Sea)

“…Furthermore, trawling activities are liable to cause the resuspension of considerable amounts of sediments [7]. Together with post depositional evolution yielding the release of particulate-bound plutonium to the interstitial waters, these processes are liable to enhance the remobilisation and relocation of the plutonium back to the water-column, its advection to distant sites, or its transfer in the food chain.…”

Plutonium measurements by accelerator mass spectrometry at LLNL

“…1,2 Plutonium is found in fresh and sea waters, 3,4 sediments, 5,6 aerosol particles, ice cores, and groundwaters. 7 Because of the prevalence and potential health effects of these radionuclides, effort is devoted worldwide to actinide studies including basic actinide chemistry, environmental concentrations, speciation and partitioning, transport, evaluations of exposure pathways, 1,8,9 toxicokinetic studies, 10 bioassays of exposed populations, [11][12][13][14][15] risk assessments, 16 and nuclear non-proliferation and national security.…”

“…Many applications, particularly those most relevant to human health effects, require significantly higher sensitivity than is available with alpha spectrometry (~10 8 atoms 239,240 Pu per sample). As examples: daily urinary excretions of Pu in the general population are ~10 6 atoms; 11 plutonium bioassay programs require detection limits ~10 6 atoms per sample; 14 mean plutonium concentrations in non-occupationally exposed persons arẽ 10 6 -10 8 atoms per g of tissue; 1 and plutonium concentrations resulting from global fallout in the surface waters of the open ocean are ~10 6 -10 8 atoms per L. 4,21 Alpha spectrometry also does not provide 240 Pu/ 239 Pu isotopic information, which is important for understanding systems with multiple sources. Depending on the source, 240 Pu/ 239 Pu ratios can vary from <1% to greater than 30%, and significant variations exist even within global fallout.…”