University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Environmental

Classification: Environmental -> dust

Citations 3

"Inductively Coupled Plasma Spectrometry In The Study Of Childhood Soil Ingestion. 2. Methodology"
J. Anal. At. Spectrom. 1989 Volume 4, Issue 8 Pages 727-735
Xioaru Wang, Alexandra Lásztity, Miklós Viczián, Yescheskel Israel and Ramon M. Barnes

Abstract: In a study aimed at quantifying the amount of soil ingested by infants and toddlers, faeces and urine collected in commodes or on diapers, together with home and pre-school dust, soil and food samples, were analyzed for Al, Ba, Mn, Si, Ti, V, Y and Zr by ICP-AES with multi-channel and sequential instruments, and V, Y and Zr were also determined by ICP-MS with flow injection sample introduction. Protocols are described for sample prep., and for online dilution and calibration for ICP-MS. Results obtained on standard solution and on reference soil and dust were in good agreement with certified or recommended values, and results by ICP-AES and ICP-MS were not statistically different, although those by ICP-MS were more precise. Flow injection ICP-MS is recommended for determining V, Y and Zr, which are present at low concentration.
Aluminum Barium Manganese Silicon Titanium Yttrium Sample preparation Spectrophotometry Mass spectrometry Reference material

"Determination Of Low Amounts Of Platinum In Environmental And Biological Materials Using Thermospray Nebulization Inductively Coupled Plasma-mass Spectrometry"
Fresenius J. Anal. Chem. 1996 Volume 354, Issue 5-6 Pages 664-667
M. Parent, H. Vanhoe, L. Moens and R. Dams

Abstract: Freeze-dried urine (SRM 2670), plant tissue, and soil or dust (0.1 g) were decomposed with HNO3, HNO3/HClO4 or HNO3/HClO4/HF, respectively. The solutions were heated with aqua regia then HNO3 was removed by evaporation. SnCl2 was added to convert the Pt(IV) to Pt(II). The resulting bis(carboxymethyl)dithiocarbamate complex of Pt(II) was adsorbed on to XAD-4 resin, then back-eluted with ethanol (idem, Biol. Trace Elem. Res., 1994, 43-45, 109). The ethanol was evaporated and the residue was dissolved in 0.5 mL 0.14 M HNO3 containing IR as internal standard. This procedure separated Pt from most matrix elements including Hf. Portions (0.1 ml) were introduced by flow injection into a thermospray nebulizer and the Pt was determined by ICP-MS. Recoveries were variable (from 62-102%) so isotope dilution was carried out with a 194Pt-enriched Pt sponge before the decomposition. The detection limit was 1 pg absolute. The results compared well with those obtained by other methods, e.g., electrothermal AAS or NAA and the certified value.
Platinum Platinum-194 Sample preparation Mass spectrometry Mass spectrometry Reference material Method comparison

"Flow Injection Hydride-generation Atomic Absorption Spectrometry (FI-HG-AAS) And Spectrophotometric Methods For Determination Of Lead In Environmental Samples"
Environ. Technol. 1996 Volume 17, Issue 12 Pages 1327-1337
Samanta G.; Chakraborti D.

Abstract: Soil or dust (0.25-0.5 g) was digested with 2 mL HNO3 and 0.5 mL 30% H2O2 at 120°C in a PTFE bomb (details given). The digest was evaporated, the residue was dissolved in ~0.1N-HNO3 and the solution was filtered. A portion (50 µL) was injected into a stream (1 ml/min) of 6% HNO3 containing 9% ammonium persulfate which merged with a stream (1 ml/min) of 1% NaOH containing 8% NaBH4 for hydride generation, followed by AAS (details given). Alternatively, a portion of digest containing methyl orange indicator was adjusted to ~pH 3.6 with 0.1N-KOH, mixed with phthalate buffer of pH 3.6, and shaken with 10 mL portions of dithizone in CHCl3 until the organic phase became green. The aqueous phase was washed with CHCl3, then mixed with hydroxylammonium chloride and HCl. Pb was extracted by shaking the solution with dibenzyldithiocarbamate, the extract was evaporated, the residue heated with HClO4 and then boiled with water. The solution was mixed with ammonia buffer of pH 10 and 0.05% 4-(2-pyridylazo)resorcinol monosodium salt solution prior to absorbance measurement at 530 nm. The detection limits for the two methods were 2 µg/l Pb and 0.5 mg/l Pb, respectively. The results were compared with those obtained by ICP-AES and flame AAS.
Lead Spectrophotometry Method comparison Dithizone