Assessing radiation impact at a protected coastal sand dune site: an intercomparison of models for estimating the radiological exposure of non-human biota

This paper presents the application of three publicly available biota dose assessment models (the ERICA Tool, R&D128/SP1a and RESRAD-BIOTA) to an assessment of the Drigg coastal sand dunes. Using measured ⁹⁰Sr, ⁹⁹Tc, ¹³⁷Cs, ²³⁸Pu, ^239+240Pu and ²⁴¹Am activity concentrations in sand dune soil, activity concentration and dose rate predictions are made for a range of organisms including amphibians, birds, invertebrates, mammals, reptiles, plants and fungi. Predicted biota activity concentrations are compared to measured data where available. The main source of variability in the model predictions is the transfer parameters used and it is concluded that developing the available transfer databases should be a focus of future research effort. The value of taking an informed user approach to investigate the way in which models may be expected to be applied in practice is highlighted and a strategy for the future development of intercomparison exercises is presented.     

Post-rehabilitation environmental hazard of Cu, Zn, As and Pb at the derelict Conrad Mine, eastern Australia

A post-rehabilitation audit of the derelict Conrad base metal mine, eastern Australia, indicates ongoing environmental hazard regarding acid mine drainage and concentrations of arsenic and lead to 3 wt% in the soil and sediment. In order to rehabilitate remote contaminated sites effectively, on-site analyses should be carried out to ensure that the materials used to rehabilitate the site are not contaminant-bearing. Understanding the geomorphic setting of the rehabilitated areas is also important in understanding where, and for what period, contaminated materials might be stored in fluvial systems downstream of mine workings. Chemical and geomorphic audits should form a fundamental part of all rehabilitation works to ensure favourable environmental outcomes.     

New Zealand kiwifruit growers’ vulnerability to climate and other stressors

Commercial cultivation of kiwifruit in New Zealand is concentrated in a relatively small area of the North Island. Cultivation is economically significant and growing quickly. However, current understanding of vulnerability for this, and other primary sector activities in New Zealand, makes almost exclusive use of linear outcome-oriented frameworks. Drawing on in-depth, semi-structured interviews with kiwifruit growers and orchard managers, workshops and analysis of secondary data, a “bottom-up” contextual assessment of vulnerability was developed and empirically applied. The findings suggest that climate and markets are the main sources of exposure for growers, with sensitivity moderated by location. Growers employ mostly short-term, reactive adaptive strategies to manage climate exposure and sensitivity, but have less capacity to respond to market-related stressors. Warmer and drier conditions are likely to have adverse effects for kiwifruit production and compound existing vulnerabilities. An ageing population and other processes of rural change may also constrain future adaptation. In order to realise opportunities and minimise losses, longer-term strategic responses are required. The paper demonstrates the need to move beyond outcome-oriented and model-based vulnerability assessments in New Zealand, to consider the broad range of the factors that contribute to vulnerability in the nation’s agricultural sectors. It provides a basis for further consideration of multiple exogenous impacts in the industry and confirms the critical importance of qualitatively vulnerability assessments to determine spatially specific outcomes.     

Possible maternal offloading of metals in the plasma,uterine and capsule fluid of pregnant ragged-tooth sharks (Carcharias taurus) on the east coast of South Africa

Environmental Science and Pollution Research - We studied the possible metal offloading onto the progeny of three pregnant female ragged-tooth sharks (Carcharias taurus) (C. taurus). The presences...     

Water quality impacts on sorbent efficacy for per- and polyfluoroalkyl substances treatment of groundwater

Per- and polyfluoroalkyl substances (PFAS) are a large group of synthetic compounds that have emerged as chemicals of concern in drinking water and groundwater. Typically, such waters are treated to remove PFAS by passing the water through a bed of sorbent material (e.g., activated carbon and anion exchange resins [AIX]). However, the efficacy of these sorbents varies depending on the types and concentrations of PFAS, in addition to water quality conditions such as organic matter content and conductivity (ionic strength). The choice of sorbent material to effectively treat PFAS in complex natural waters will, therefore, depend upon site water quality and PFAS conditions. To help inform these decisions, a series of evaluations using a rapid small-scale column test approach was conducted with two sorbent materials (a granulated activated carbon [GAC] and an AIX), individually and combined, under conditions where conductivity, pH, and organic carbon concentrations were varied in a semifactorial approach. Artificial groundwater batches were prepared to meet these test conditions and spiked with six PFAS compounds (perfluorobutane sulfonic acid [PFBS], perfluorobutanoic acid [PFBA], perfluorohexane sulfonic acid [PFHxS], perfluorohexanoic acid [PFHxA], perfluorooctane sulfonic acid [PFOS], and perfluorooctanoic acid [PFOA]), passed through small columns packed with ground sorbent material for ∼30,000 bed volumes of water for single sorbent treatments and ∼20,000 bed volumes for combined sorbent treatments, during which samples of effluent were captured and analyzed to quantify breakthrough of PFAS from the sorbent materials over time. AIX was found to be more effective than GAC at removing the tested perfluoroalkyl sulfonic acids (PFBS, PFHxS, and PFOS), but GAC was similarly or more effective than AIX at removing perfluorocarboxylic acids (PFBA, PFHxA, and PFOA) under high conductivity conditions. Overall, the efficacy of AIX at removing PFAS was more strongly impacted by organic carbon and conductivity than GAC, while pH had less of an effect on either sorbent's efficacy compared to the other test conditions.