Publications by authors named "Brenda Howard"

Article Synopsis
  • Long-term experiments in the Chornobyl Exclusion zone studied technetium (Tc) transfer to various food plants from different soil types, revealing varying uptake levels.
  • In the first two years, soil type did not significantly influence Tc uptake, with radish and lettuce exhibiting high concentration ratios (CR) compared to potato and wheat.
  • After 8-9 years, Tc uptake by wheat decreased significantly, and most of the initial Tc had migrated or been absorbed by plants, indicating a relatively quick removal process from arable soil.
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The conditions of COVID-19 have caused moral distress in healthcare workers. Occupational therapists have had to adapt to these unknown times to best treat their clients. The purpose of this study was to explore the experience of moral distress in occupational therapists during the time of COVID-19.

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A prototype tool has been developed for deriving sediment distribution coefficients,, in the marine environment by harvesting simultaneous measurements of activity concentrations of radionuclides in seawater and sediments based on the International Atomic Energy Agency's Marine Radioactivity Information System (MARIS). As a case study, thevariability in the Baltic Sea was investigated as this region has been extensively monitored by HELCOM since 1984 resulting in a comprehensive dataset with good spatial and temporal coverage and required ancillary parameters. The prototype tool was used to derive a dataset ofapparentvalues derived from measurements of seawater and sediment in quasi-equilibrium conditions from the Baltic Sea over a period of approximately 35 years.

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An international review of radioecological data derived after the accident at the Fukushima Daiichi nuclear power plant was an important component of activities in working group 4 of the IAEA Models and data for radiological impact assessment, phase II (MODARIA II) programme. Japanese and international scientists reviewed radioecological data in the terrestrial and aquatic environments in Japan reported both before and after the accident. The environmental transfer processes considered included: (a) interception and retention radionuclides by plants, (b) loss of radionuclides from plant and systemic transport of radionuclides in plants (translocation), (c) behaviour of radiocaesium in soil, (d) uptake of radionuclides from soil by agricultural crops and wild plants, (e) transfer of radionuclides from feedstuffs to domestic and wild animals, (f) behaviour of radiocaesium in forest trees and forest systems, (g) behaviour of radiocaesium in freshwater systems, coastal areas and in the ocean, (h) transport of radiocaesium from catchments through rivers, streams and lakes to the ocean, (i) uptake of radiocaesium by aquatic organisms, and (j) modification of radionuclide concentrations in food products during food processing and culinary preparation.

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A revision of the International Atomic Energy Agency (IAEA) Technical Report Series No. 472 (TRS 472) transfer parameter data for root uptake of radionuclides by crops in tropical environments was conducted under the IAEA Modelling and Data for Radiological Impact Assessments (MODARIA II) programme (2016-2019). Data on concentration ratios between plant and soil (CR) were collated and summarised following a specific data selection process based on the Köppen-Geiger classification of tropical (class A) climates.

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There is a need to prioritise the requirements for data to assess the radiological risk for fauna and flora, as inevitable large data gaps occur due to the large number of combinations of radionuclides and organisms for which doses need to be assessed. The potentially most important dose-forming radionuclide-pathways combinations need to be identified to optimize filling these gaps. Few attempts have been made to classify the importance of isotopes with regard to radiation protection of the environment.

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Radiocaesium (Cs) mobility in soil is initially relatively high when the nuclide first comes into contact with soil, after which the mobile fraction decreases with time due to Cs fixation to soil particles (aging effect). Consequently, the Cs activity concentration in plants grown in soil was expected to decrease with time after the Fukushima Daiichi nuclear power plant accident in 2011. In this study, we collated data on concentration ratios (CR) of Cs between brown rice grain and paddy soil and compared CR values reported for periods before and after the accident.

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Many of the freshwater K values required for quantifying radionuclide transfer in the environment (e.g. ERICA Tool, Symbiose modelling platform) are either poorly reported in the literature or not available.

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In response to a critical need for tobacco cessation services among justice-involved populations, Arkansas Community Correction (ACC) partnered with the University of Colorado's Behavioral Health & Wellness Program in 2013 to implement the DIMENSIONS: Tobacco Free Program within all probation, parole, and drug court units. In the first 2 years of this statewide, evidence-based program, more than 1,100 individuals from 33 ACC area office locations attended tobacco-free group sessions and provided data on tobacco use and readiness to quit. Results demonstrated a significant reduction in tobacco use among participants as well as increased knowledge, confidence, and intent to quit.

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Extensive remediation was conducted on contaminated landscapes after the Chernobyl accident in 1986 and the Fukushima Daiichi accident in 2011. A comparison is made of a range of different features relevant to each accident including the characteristics of the contamination and the landscapes affected, the radiological criteria, the designation of areas to be remediated and the remediation measures adopted.

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The quality and quantity of data used to derive transfer parameter values for milk are variable and there are many data gaps for elements/radionuclides which may need to be considered for risk assessment of the agricultural foodchain. There has been a recent focus on critically evaluating current methods to fill data gaps and on identifying extrapolation methods to derive suitable values for the elements, and particularly radioisotopes, with no or sparse data. The relationship between fractional absorption of elements in the ruminant gastrointestinal tract and transfer to milk has been explored to determine whether knowledge of the former can be used to predict the latter.

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Since the Fukushima Dai-ichi accident, monitoring of tissues from hunted game animals ensures compliance with the standard food limits for radionuclides in Japan. We quantified the transfer of (137)Cs from contaminated land to game animals using the Aggregated transfer factor (Tag = activity concentration in meat [Bq kg(-1) fw]/amount in soil [Bq m(-2)]) of (137)Cs for Asian black bear, wild boar, sika deer, green pheasant, copper pheasant and wild duck, collected between 2011 and 2015. Open data sources were used from Fukushima, Miyagi, Ibaraki, Tochigi, and Gunma prefectures.

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Long term spatial and temporal variations in radionuclide activity have been measured in a contaminated ungrazed saltmarsh near Ravenglass, Cumbria. Over a twenty-five year period there has been a decrease in activity concentration with (106)Ru and (137)Cs showing the highest rate of change followed by Pu alpha and (241)Am. A number of factors contribute to the reduction with time; including radiological half lives, discharge and remobilisation.

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The transfer characteristics of (137)Cs, (85)Sr and (65)Zn to earthworms (Eisenia andrei) in soils with different amounts of the radionuclides have been investigated. The time-dependent whole-body concentration ratios (CR) were derived for worms in artificially contaminated soils with three different activity concentrations. Two parameters of a first order kinetic model, the equilibrium concentration ratio (CR(eq)) and the effective loss rate constant (k), were estimated by a comparison of experimental CR results with model predictions.

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Initial information since the releases of radioactive materials from the Fukushima Daiichi nuclear power plant, in Japan, shows that some animal food products are contaminated with 131I (mostly milk) and, to a lesser extent with 134Cs and 137Cs. Current knowledge on the transfer of these radioisotopes to animal products and available relevant countermeasures and management options to reduce radiation doses to humans are summarized. Much of this knowledge was obtained during the years of global fallout from atmospheric nuclear weapons tests and the response to the Chernobyl accident, in Ukraine in 1986.

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Environmental monitoring programs often measure contaminant concentrations in animal tissues consumed by humans (e.g., muscle).

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Criteria are needed to be able to judge the level of risk associated with dose rates estimated for non-human biota. In this paper, European guidance on the derivation of predicted no-effect chemical concentrations has been applied to appropriate radiation sensitivity data. A species sensitivity distribution fitted to the data for all species resulted in a generic predicted no-effect dose rate of 10 microGy h(-1).

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Few data are available to quantify the transfer of both natural and anthropogenic radionuclides to detritivorous invertebrates to facilitate estimation of the internal dose to such biota in models used to assess radiation exposure. To enhance the available data, activity concentrations of (137)Cs, (40)K, (90)Sr, (239 + 240)Pu, (241)Am, (235)U and (238)U were measured in ants (Formicidae) and corresponding undisturbed soil collected from the Zlatibor mountain in Serbia and ant/soil concentration ratios (CR) calculated. The (241)Am concentration ratios for ants were fourfold higher than those calculated for ants in a previous study whereas they are similar to the more numerous data previously reported for a range of detritivorous invertebrates in other studies.

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Over the last decade a number of models and approaches have been developed for the estimation of the exposure of non-human biota to ionising radiations. In some countries these are now being used in regulatory assessments. However, to date there has been no attempt to compare the outputs of the different models used.

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A wide range of different countermeasures has been used to mitigate the consequences of the Chernobyl accident for agriculture in affected regions in Belarus, Russia and Ukraine. The paper comprehensively brings together key data on countermeasure application over twenty years for all three countries and critically evaluates the response to the accident with respect to agriculture. The extents of countermeasures implementation in various periods following the ChNPP accident are documented.

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