Publications

High As groundwater is widely distributed all over the world, which has posed a significant health impact on millions of people. Iron isotopes have recently been used to characterize Fe cycling in aqueous environments, but there is no information on Fe isotope characteristics in the groundwater. Since groundwater As behavior is closely associated with Fe cycling in the aquifers, Fe isotope signatu

Volcanic eruptions can produce a wide range of hazards. Although phenomena such as pyroclastic density currents and surges, sector collapses, lahars and ballistic blocks are the most destructive and dangerous, volcanic ash is by far the most widely distributed eruption product1 and the most likely to be encountered by the public. Following an eruption, the public, civil authorities and agricultura

Seepage of coal-bed methane (CBM) through soils is a potential source of atmospheric CH4 and also a likely source of ancient (i.e. 14C-dead) carbon to soil microbial communities. Natural abundance 13C and 14C compositions of bacterial membrane phospholipid fatty acids (PLFAs) and soil gas CO2 and CH4 were used to assess the incorporation of CBM-derived carbon into methanotrophs and other members o

Stream sediment, stream water, and fish were collected from a broad region to evaluate downstream transport and dispersion of mercury (Hg) from inactive mines in the Monte Amiata Hg District (MAMD), Tuscany, Italy. Stream sediment samples ranged in Hg concentration from 20 to 1,900 ng/g, and only 5 of the 17 collected samples exceeded the probable effect concentration for Hg of 1,060 ng/g, above w

Background: In 2010, Médecins Sans Frontières discovered a lead poisoning outbreak linked to artisanal gold processing in northwestern Nigeria. The outbreak has killed approximately 400 young children and affected thousands more. Objectives: Our aim was to undertake an interdisciplinary geological- and health-science assessment to clarify lead sources and exposure pathways, identify additional to

The levee system of the lower American River in Sacramento, California, is situated above a mixed lithology of alluvial deposits that range from clay to gravel. In addition, sand deposits related to hydraulic mining activities underlie the floodplain and are preferentially prone to scour during high-flow events. In contrast, sections of the American River channel have been observed to be scour res

Effects of contaminants on adult aquatic insect emergence are less well understood than effects on insect larvae. We compared responses of larval density and adult emergence along a metal contamination gradient. Nonlinear threshold responses were generally observed for larvae and emergers. Larval densities decreased significantly at low metal concentrations but precipitously at concentrations of m

In this study we report uranium analysis for human semen samples. Uranium quantification was performed by inductively coupled plasma mass spectrometry. No additives, such as chymotrypsin or bovine serum albumin, were used for semen liquefaction, as they showed significant uranium content. For method validation we spiked 2 g aliquots of pooled control semen at three different levels of uranium: low

Characterization of ore and waste-rock material using automated quantitative micro-mineralogical techniques (e.g., QEMSCAN® and MLA) has the potential to complement traditional acid-base accounting and humidity cell techniques when predicting acid generation and metal release. These characterization techniques, which most commonly are used for metallurgical, mineral-processing, and geometallurgica

Exposure to fine particulate matter (PM) is generally acknowledged to increase risk for human morbidity and mortality. However, particulate matter (PM) research has generally examined anthropogenic (industry and combustion by-products) sources with few studies considering contributions from geogenic PM (produced from the Earth by natural processes, e.g., volcanic ash, windborne ash from wildfires,

The Pebble deposit is located about 320 km southwest of and 27 km northwest of the village of Iliamna in Alaska (Fig. 1A). It is one of the largest porphyry deposits in terms of contained Cu (Fig. 2A) and it has the largest Au endowment of any porphyry deposit in the world (Fig. 2B). The deposit comprises the Pebble West and Pebble East zones that represent two coeval hydrothermal centers within a

Bromine and chlorine are important halogens for fluid source identification in the Earth's crust, but until recently we lacked routine analytical techniques to determine the concentration of these elements in situ on a micrometer scale in minerals and fluid inclusions. In this study, we evaluate the potential of in situ Cl and Br measurements by LA-ICP-MS through analysis of a range of scapolite g