Jessica Velicogna

Bio: Jessica Velicogna is an academic researcher from Environment Canada. The author has contributed to research in topics: Eisenia andrei & Loam. The author has an hindex of 3, co-authored 3 publications receiving 89 citations.

Extracting Metallic Nanoparticles from Soils for Quantitative Analysis: Method Development Using Engineered Silver Nanoparticles and SP-ICP-MS

Abstract: The lack of an efficient and standardized method to disperse soil particles and quantitatively subsample the nanoparticulate fraction for characterization analyses is hindering progress in assessing the fate and toxicity of metallic engineered nanomaterials in the soil environment. This study investigates various soil extraction and extract preparation techniques for their ability to remove nanoparticulate Ag from a field soil amended with biosolids contaminated with engineered silver nanoparticles (AgNPs), while presenting a suitable suspension for quantitative single-particle inductively coupled plasma mass spectroscopy (SP-ICP-MS) analysis. Extraction parameters investigated included reagent type (water, NaNO3, KNO3, tetrasodium pyrophosphate (TSPP), tetramethylammonium hydroxide (TMAH)), soil-to-reagent ratio, homogenization techniques as well as procedures commonly used to separate nanoparticles from larger colloids prior to analysis (filtration, centrifugation, and sedimentation). We assessed the ef...

Estimation of the bioaccumulation potential of a nonchlorinated bisphenol and an ionogenic xanthene dye to Eisenia andrei in field-collected soils, in conjunction with predictive in silico profiling.

Abstract: In silico–based model predictions, originating from structural and mechanistic (e.g., transport, bioavailability, reactivity, and binding potential) profiling, were compared against laboratory-derived data to estimate the bioaccumulation potential in earthworms of 2 organic substances (1 neutral, 1 ionogenic) known to primarily partition to soil. Two compounds representative of specific classes of chemicals were evaluated: a nonchlorinated bisphenol containing an –OH group (4,4′-methylenebis[2,6-di-tert-butylphenol] [Binox]), and an ionogenic xanthene dye (2′,4′,5′,7′-tetrabromo-4,5,6,7-tetrachloro-3′,6′-dihydroxy-, disodium salt [Phloxine B]). Soil bioaccumulation studies were conducted using Eisenia andrei and 2 field-collected soils (a clay loam and a sandy soil). In general, the in silico structural and mechanistic profiling was consistent with the observed soil bioaccumulation tests. Binox did not bioaccumulate to a significant extent in E. andrei in either soil type; however, Phloxine B not only accumulated within tissue, but was not depurated from the earthworms during the course of the elimination phase. Structural and mechanistic profiling demonstrated the binding and reactivity potential of Phloxine B; this would not be accounted for using traditional bioaccumulation metrics, which are founded on passive-based diffusion mechanisms. This illustrates the importance of profiling for reactive ionogenic substances; even limited bioavailability combined with reactivity can result in exposures to a hazardous substance not predictable by traditional in silico modeling methods. Environ Toxicol Chem 2014;33:308–316. © 2013 SETAC

Mass Loading and Fate of Linear and Cyclic Siloxanes in a Wastewater Treatment Plant in Greece

Abstract: The occurrence and fate of 5 cyclic (D3 to D7) and 12 linear (L3 to L14) siloxanes were investigated in raw and treated wastewater (both particulate and dissolved phases) as well as in sludge from a wastewater treatment plant (WWTP) in Athens, Greece. Cyclic and linear siloxanes (except for L3) were detected in all influent wastewater and sludge samples at mean concentrations of (sum of 17 siloxanes) 20 μg L(-1) and 75 mg kg(-1), respectively. The predominant compounds in wastewater were L11 (24% of the total siloxane concentration), L10 (16%), and D5 (13%), and in sludge were D5 (20%) and L10 (15%). The distribution of siloxanes between particulate and dissolved phases in influents differed significantly for linear and cyclic siloxanes. Linear siloxanes showed higher solid-liquid distribution coefficients (log K(d)) than did cyclic compounds. For 10 of the 16 compounds detected in influents, the removal efficiency was higher than 80%. Sorption to sludge and biodegradation and/or volatilization losses are important factors that affect the fate of siloxanes in WWTPs. The mean total mass of siloxanes that enter into the WWTP via influent was 15.1 kg per day(-1), and the mean total mass released into the environment via effluent was 2.67 kg per day(-1).

A critical review of single particle inductively coupled plasma mass spectrometry – A step towards an ideal method for nanomaterial characterization

Abstract: Single particle inductively coupled plasma mass spectrometry (spICP-MS or SP-ICP-MS depending on the author) is becoming an important tool for the characterization of nanoparticles (NPs). The method allows determining the size, size distribution, and particle number concentrations of NPs in suspensions after a mere few minutes of measurement. This review is modeled after the concept of “an ideal method for atomic spectroscopy” introduced by Gary M. Hieftje in his publication dedicated to Howard Malmstadt. This review discusses the instrumental developments in spICP-MS of recent years step-by-step, from the sample introduction system to the detector. The authors identify necessary improvements and suggest directions for further developments which have the potential to bring the method closer to “an ideal method for atomic spectroscopy”. The review also discusses the literature on coupling spICP-MS to separation and fractionation techniques including capillary electrophoresis (CE), field flow fractionation (FFF), and differential mobility analysis (DMA). The second part of the review is dedicated to the applications of spICP-MS. Key steps in sample preparation and selected instrumental conditions that were used in the published literature are summarized in a tabular form. Most frequently, spICP-MS is used for silver (Ag), gold (Au), and titanium dioxide (TiO2) nanomaterial analysis. Data acquisition was typically performed with millisecond dwell times in the past while a time resolution of hundreds of microseconds has been used more often in the last five years. The table may serve as a guide to choose an experimental procedure depending on the matrix that is present in the sample under investigation.