Concern about children's exposure to arsenic (As) from wood treated with chromated-copper-arsenate (CCA) led to its withdrawal from residential use in 2004. However, due to its effectiveness, millions of American homes still have CCA-wood decks on which children play. This study evaluated the effects of three deck-cleaning methods on formation of dislodgeable As and hexavalent chromium (CrVI) o...

This paper describes the relationships between ultra-violet emission, ozone generation and CrVI production in MIG welding which were measured as a function of shield gas flow rate, welding voltage, electrode stick-out and shield gas composition using an automatic welding rig that permitted MIG welding under reproducible conditions. The experimental results are interpreted in terms of the physic...

The remediation of chromium-contaminated sites requires knowledge of the processes that control the migration and transformation of chromium. Advection, dispersion, and diffusion are physical processes affecting the rate at which contaminants can migrate in the subsurface. Heterogeneity is an important factor that affects the contribution of each of these mechanisms to the migration of chromium...

Heavy metals that contaminate soils and water usually exist in various oxidation states and form a number of compounds with different physical and chemical characteristics. These differences are often reflected in dramatic variation in toxicokinetic and biologic properties. Such variation in properties, critical in determining intrinsic toxicity, often causes a great deal of uncertainty in anal...

Conventional soil solution sampling of species-sensitive inorganic contaminants, such as hexavalent chromium (CrVI), may induce interconversions due to disruption system equilibrium. The temporal resolution that these methods afford also be insufficient capture dynamic interactions or require time-consuming and expensive analysis. Microdialysis (MD) is emerging a minimally invasive passive meth...

Hexavalent chromium (VI) compounds are widely used in industry, while trivalent chromium (III) is used as a nutritional supplement. CrVI is generally considered more toxic and carcinogenic than its trivalent form and the toxicity of this metal is associated with free radical processes generating reactive oxygen species (ROS). The detailed mechanism of ROS formation by chromium and its compounds...

Ethylenediaminetetraacetic (EDTA), cyclohexane-1,2-diaminetetraacetic (CDTA) and diethylenetriaminepentaacetic (DTPA) acids were investigated and compared as complexing agents for the speciation of chromium(VI/III), vanadium(V/IV) and iron(III/II) ions by capillary electrophoresis. The chromium(III) was selectively chelated with DTPA in order to impart a negative charge and similar mobility to ...

BACKGROUND Evaluating the impact of federally funded research with a broad, methodical, and objective approach is important to ensure that public funds advance the mission of federal agencies. OBJECTIVES We aimed to develop a methodical approach that would yield a broad assessment of National Toxicology Program's (NTP's) effectiveness across multiple sectors and demonstrate the utility of the...

The objective of this study was to develop a low-cost and eco-friendly adsorbent from agro-industrial waste for the removal hexavalent chromium in aqueous medium. (BMC) produced yellow mombin (Spondias L.) seeds characterized by determination chemical composition, thermal analysis (thermogravimetric (TG) differential (DTA)), Fourier transform infrared spectroscopy (FTIR), pH suspension point ze...