Impacts of the Fukushima nuclear power plants on marine radioactivity

Author Posting. © American Chemical Society, 2011. This article is posted here by permission of American Chemical Society for personal use, not for redistribution. The definitive version was published in Environmental Science and Technology 45 (2011): 9931–9935, doi:10.1021/es202816c.The impacts on the ocean of releases of radionuclides from the Fukushima Dai-ichi nuclear power plants remain unclear. However, information has been made public regarding the concentrations of radioactive isotopes of iodine and cesium in ocean water near the discharge point. These data allow us to draw some basic conclusions about the relative levels of radionuclides released which can be compared to prior ocean studies and be used to address dose consequences as discussed by Garnier-Laplace et al. in this journal.(1) The data show peak ocean discharges in early April, one month after the earthquake and a factor of 1000 decrease in the month following. Interestingly, the concentrations through the end of July remain higher than expected implying continued releases from the reactors or other contaminated sources, such as groundwater or coastal sediments. By July, levels of 137Cs are still more than 10 000 times higher than levels measured in 2010 in the coastal waters off Japan. Although some radionuclides are significantly elevated, dose calculations suggest minimal impact on marine biota or humans due to direct exposure in surrounding ocean waters, though considerations for biological uptake and consumption of seafood are discussed and further study is warranted.Funding for this work to KOB is from the Gordon and Betty Moore Foundation as well as the Chemical Oceanography Program of the US National Science Foundation

‘Can you dig it?’ Developing an approach to validly assessing diverse skills in an archaeological context

This paper outlines a case study of an assessment development process which contrasts with more recent ‘top-down’ trends in assessment which tend to leave assessment development processes opaque to users. This paper describes the processes of a collaborative, multi-agency project which set out to develop an assessment framework which would appropriately recognise the various skills present in the Higher Education Field Academy; a widening participation programme aiming to boost the educational aspirations, enthusiasm and attainment of secondary school students through their engagement in archaeological excavation. The case study describes the stages of building an assessment framework that was sympathetic to the intentions of a learning programme whilst providing robust observation-based outcomes that avoided heavy assessment processes that could corrupt learning relationships. The challenges involved in this development process have important parallels with vocational assessment; not least in providing an example of a localised development of an observation-based assessment model which can be used in diverse settings. The insights gained from this case study are useful for others who are engaged in localised assessment development processes

radionuclides behavior in fruit plants

This paper summarizes research carried out on fruits by the Universita Cattolica del Sacro Cuore (UCSC) in Piacenza, Italy. Among the fruit crops studied, strawberry, blackberry, grapevine, apple, pear, and olive, research on strawberry and blackberry was funded by the Food Standard Agency (UK). Fruit plants were grown in pots, kept under tunnels or in open field, and contaminated with 134Cs and 85Sr via leaves or via soil. Interception in strawberry plants ranges 39–17 % for 134Cs, from anthesis (April) to predormancy (November). Leaf-to-fruit translocation occurs to a greater extent for 134Cs than for 85Sr. The distribution of contamination in fruit crops is an element-specific process: 134Cs is preferentially allocated to fruits and 85Sr to leaves. However, the activity in leaves is also species-specific: fruit species show different leaf-to-fruit translocation. Results on apple, pear, and grape crops indicate that the highest transfer from leaf to fruit occurs in apple crops. Olive plants also show 134Cs translocation from leaves to trunks. Grapevines grown on mineral soil show a root uptake higher for 85Sr than for 134Cs, while strawberries grown on a peat substrate show a root uptake higher for 134Cs than for 85Sr. Rinsing directly contaminated fruits removes 85Sr (36 %) to a greater degree than 134Cs (24 %). Transfer to olive oil is low. A 57 % of 134Cs is transferred from grapes to white wine