HumanISE - Indexed Articles in Journals

Permanent URI for this collection


Recent Submissions

Now showing 1 - 5 of 170
  • Item
    Evaluation of a new optic-enabled portable XRF instrument for measuring toxic metals/metalloids in consumer goods and cultural products
    ( 2016) Diana Filipa Guimarães ; Praamsma,ML ; Parsons,PJ ; 6888
    X-ray fluorescence spectrometry (XRF) is a rapid, non-destructive multi-elemental analytical technique used for determining elemental contents ranging from percent down to the µg/g level. Although detection limits are much higher for XRF compared to other laboratory-based methods, such as inductively coupled plasma mass spectrometry (ICP-MS), ICP-optical emission spectrometry (OES) and atomic absorption spectrometry (AAS), its portability and ease of use make it a valuable tool, especially for field-based studies. A growing necessity to monitor human exposure to toxic metals and metalloids in consumer goods, cultural products, foods and other sample types while performing the analysis in situ has led to several important developments in portable XRF technology. In this study, a new portable XRF analyzer based on the use of doubly curved crystal optics (HD Mobile®) was evaluated for detecting toxic elements in foods, medicines, cosmetics and spices used in many Asian communities. Two models of the HD Mobile® (a pre-production and a final production unit) were investigated. Performance parameters including accuracy, precision and detection limits were characterized in a laboratory setting using certified reference materials (CRMs) and standard solutions. Bias estimates for key elements of public health significance such as As, Cd, Hg and Pb ranged from -10% to 11% for the pre-production, and -14% to 16% for the final production model. Five archived public health samples including herbal medicine products, ethnic spices and cosmetic products were analyzed using both XRF instruments. There was good agreement between the pre-production and final production models for the four key elements, such that the data were judged to be fit-for-purpose for the majority of samples analyzed. Detection of the four key elements of interest using the HD Mobile® was confirmed using archived samples for which ICP-OES data were available based on digested sample materials. The HD Mobile® XRF units were shown to be suitable for rapid screening of samples likely to be encountered in field based studies. © 2016 Elsevier B.V.
  • Item
    Evaluation of portable XRF instrumentation for assessing potential environmental exposure to toxic elements
    ( 2016) McIntosh,KG ; Diana Filipa Guimarães ; Cusack,MJ ; Vershinin,A ; Chen,ZW ; Yang,K ; Parsons,PJ ; 6888
  • Item
    The Structure of Climate Variability Across Scales
    ( 2020) Franzke,CLE ; Susana Alexandra Barbosa ; Blender,R ; Fredriksen,HB ; Laepple,T ; Lambert,F ; Nilsen,T ; Rypdal,K ; Rypdal,M ; Scotto,MG ; Vannitsem,S ; Watkins,NW ; Yang,LC ; Yuan,NM ; 6363
  • Item
    Ambient radioactivity and atmospheric electric field: A joint study in an urban environment
    ( 2020) Susana Alexandra Barbosa ; 6363
    Ambient radioactivity and atmospheric electricity are inextricably linked phenomena. In order to assess the role of ambient radioactivity in the local variability of the atmospheric electric field at an urban site, simultaneous measurements of radon concentration, gamma radiation, and atmospheric electric field are carried out in the city of Porto, Portugal. Both radon and gamma radiation display an average daily cycle peaking before sunrise, but with considerable variability from day to day, particularly in amplitude. The atmospheric electric field displays a daily cycle with a minimum at dawn and maximum in the early afternoon, as well as a secondary peak in the early morning. The temporal variation of the daily patterns is analysed by means of an empirical orthogonal function analysis, and related to local meteorological parameters. The variability of the local atmospheric electric field is mainly determined by aerosol transport and accumulation close to the surface associated with local meteorological conditions and atmospheric stability rather than by conductivity variations associated with ambient radioactivity. © 2020 Elsevier Ltd
  • Item
    Morphological controls and statistical modelling of boulder transport by extreme storms
    ( 2020) Oliveira,MA ; Scotto,MG ; Susana Alexandra Barbosa ; de Andrade,CF ; Freitas,MD ; 6363