A5042247746- Heavy metals in environment
- Radioactivity and Radon Measurements
- Heavy Metal Exposure and Toxicity
- Geochemistry and Geologic Mapping
- Arsenic contamination and mitigation
- Mine drainage and remediation techniques
- Soil Geostatistics and Mapping
- Geophysical Methods and Applications
- Seismic Waves and Analysis
- Soil and Unsaturated Flow
- Chromium effects and bioremediation
- Toxic Organic Pollutants Impact
- Geophysical and Geoelectrical Methods
- Soil Carbon and Nitrogen Dynamics
- Environmental and Social Impact Assessments
- CO2 Sequestration and Geologic Interactions
- Effects and risks of endocrine disrupting chemicals
- Drilling and Well Engineering
- Groundwater flow and contamination studies
- Air Quality and Health Impacts
- Soil erosion and sediment transport
- Therapeutic Uses of Natural Elements
- Methane Hydrates and Related Phenomena
- Radioactive element chemistry and processing
- Pesticide Exposure and Toxicity
British Geological Survey
2012-2021
Queen's University
2010
Geological Survey of Canada
2010
Natural Resources Canada
2010
DHI
2006
The Ohio State University
2006
Nederlandse Internisten Vereniging
2006
Ghent University
2002-2006
Royal Military College of Canada
2006
Institut national de l'environnement industriel et des risques
2006
Soil ingestion can be a major exposure route for humans to many immobile soil contaminants. Exposure contaminants overestimated if oral bioavailability is not taken into account. Several in vitro digestion models simulating the human gastrointestinal tract have been developed assess mobilization of from during digestion, i.e., bioaccessibility. Bioaccessibility crucial step controlling To what extent determination bioaccessibility method dependent has, until now, studied. This paper...
The relative bioavailability of arsenic, antimony, cadmium, and lead for the ingestion pathway was measured in 16 soils contaminated by either smelting or mining activities using a juvenile swine model. contained 18 to 25 000 mg kg–1 As, 60 Sb, 20 184 Cd, 1460 40 214 Pb. kidney, liver, bone, urine soluble salts four elements. variety soil types, total concentrations elements, range bioavailabilities found were considered be suitable calibrating vitro Unified BARGE bioaccessibility method....
Bioaccessibility tests and mineralogical analyses were performed on arsenic-contaminated tailings soils from gold mine districts of Nova Scotia, Canada, to examine the links between soil composition, mineralogy, arsenic bioaccessibility. Arsenic bioaccessibility ranges 0.1% 49%. A weak correlation was observed total bioaccessible concentrations, not correlated with other elements. Bulk X-ray absorption near-edge structure analysis shows in these near-surface samples is mainly pentavalent...
This paper presents a multi-laboratory comparison study of in vitro models assessing bioaccessibility soil-bound lead the human gastrointestinal tract under simulated fasted and fed conditions. Oral bioavailability data from previous vivo on same soil served as reference point. In general, bioaccessible fraction was significantly (P<0.05) different between methods ranged for 2% to 33% 7% 29%. The literature were 26.2+/-8.1% conditions, compared 2.5+/-1.7% Under all returned higher values...
ABSTRACT The internal moisture dynamics of an aged (> 100 years old) railway earthwork embankment, which is still in use, are investigated using 2D and 3D resistivity monitoring. A methodology was employed that included automated ERT data capture telemetric transfer with on‐site power generation, the correction models for seasonal temperature changes translation subsurface distributions into content based on petrophysical relationships developed embankment material. Visualization as...
An investigation for assessing pulmonary bioaccessibility of metals from reference materials is presented using simulated lung fluids. The objective this paper was to contribute an enhanced understanding airborne particulate matter and its toxic potential following inhalation. A large set metallic elements (Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sr, Zn) investigated three fluids (phosphate-buffered saline, Gamble's solution artificial lysosomal fluid) on standard representing different types...
Systems and methods are described for monitoring temporal spatial moisture content changes in clay embankments using electrical resistivity tomography (ERT) imaging. The methodology is based upon development of a robust relationship between fill its use the transformation image differences terms relative changes. Moisture level movement applications exemplified two case histories from UK. first BIONICS embankment, near Newcastle (NE England), which was constructed 2005 varying degrees...
Abstract Bioaccessibility is a measurement of substance's solubility in the human gastro-intestinal system, and often used risk assessment soils. The present study was designed to determine variability among laboratories using different methods measure bioaccessibility 24 inorganic contaminants one standardized soil sample, standard reference material NIST 2710. Fourteen total 17 extraction methods. between assessed by calculating reproducibility relative deviations (RSDs), where sum...
The population of the semi-arid areas countries in East African Rift Valley (EARV) is faced with serious problems associated availability and quality drinking water. In these areas, water supply largely relies on groundwater characterised by elevated fluoride concentration (> 1.5 mg/L), resulting from interactions surrounding alkaline volcanic rocks. This geochemical anomaly often presence other naturally occurring potentially toxic elements (PTEs), such as As, Mo, U, V, which are known to...
A fed state in vitro methodology capable of use commercial testing laboratories has been developed for measuring the human ingestion bioaccessibility polyaromatic hydrocarbons (PAHs) soil (Fed ORganic Estimation Simulation Test- FOREhST). The protocol PAHs simulated gastro-intestinal fluids used methanolic KOH saponification followed by a combination polymeric sorbent solid phase extraction and silica cartridges sample cleanup preconcentration. analysis was carried out using high pressure...
Twenty samples from soils developed over the Northampton Sand ironstone formation were collected from, in and around town of Wellingborough, Northamptonshire, UK. The total arsenic (As) content ranged ca. 20–100 mg kg− 1and bioaccessible As content, as measured by a physiologically based vitro extraction test, 1 to 6 1. A chemometric algorithm for mixture resolution, when applied element organic carbon concentration soils, was able identify chemically distinct soil constituents their...
The objective of this study was to develop an in vitro respiratory uptake test determine the bioaccessibility lead derived from mining waste tailings and dusts. Samples were collected abandoned area mid-Wales, UK, < 10 μ m fraction characterized using SEM 100 XRD techniques. Gamble's Solution employed as synthetic lung fluid tests run for 630 hours a specially designed water bath. long duration specified because particulates after inhalation. Bioaccessible determined throughout final values...
Aggregate stability is an important physical indicator of soil quality, and so methods are required to measure it rapidly cost‐effectively that sufficient data can be collected detect change with adequate statistical power. The standard water‐stable aggregates (WSA) in involve sieving, but these have limitations could overcome if the were measured a laser granulometer (LG) instrument. We present novel method which LG used make two measurements continuous size distribution (<2000 µm)...
Abstract. The spatial distribution and accessibility of organic matter (OM) to soil microbes in aggregates – determined by the fine-scale, 3-D OM, pores mineral phases may be an important control on magnitude heterotrophic respiration (SHR). Attempts model SHR fine scales requires data transition probabilities between adjacent pore space a measure microbial latter. We used combination osmium staining synchrotron X-ray computed tomography (CT) determine (voxel) these three (scale 6.6 µm)...
The prime aim of our work is to report and comment on the bioaccessible concentrations - i.e., soluble content chemical elements in gastrointestinal environment that available for absorption a number essential mineral nutrients potentially harmful (PHEs) associated with deliberate ingestion African geophagical materials, namely Calabash chalk Undongo. pseudo-total 13 nutrients/PHEs were quantified following nitric-perchloric acid digestion nine different samples, contents eight these...
The relationship between As bioaccessibility using the physiologically based extraction test (PBET) and extracted by hydroxylamine hydrochloride (HH), targeting dissolution of amorphous Fe oxyhydroxides, is established in soils from British Geological Survey Geochemical Baseline SW England, UK, to represent low background high mineralised/mined soils. HH-extracted was same order magnitude as proved be a better estimate bioaccessible than total (bioaccessible - As: r = 0.955; 0.974; p-values...