Evolution of particle composition in CLOUD nucleation experiments

Sulphuric acid, ammonia, amines, and oxidised organics play a crucial role in nanoparticle formation in the atmosphere. In this study, we investigate the composition of nucleated nanoparticles formed from these compounds in the CLOUD (Cosmics Leaving Outdoor Droplets) chamber experiments at CERN (Centre européen pour la recherche nucléaire). The investigation was carried out via analysis of the particle hygroscopicity, ethanol affinity, oxidation state, and ion composition. Hygroscopicity was studied by a hygroscopic tandem differential mobility analyser and a cloud condensation nuclei counter, ethanol affinity by an organic differential mobility analyser and particle oxidation level by a high-resolution time-of-flight aerosol mass spectrometer. The ion composition was studied by an atmospheric pressure interface time-of-flight mass spectrometer. The volume fraction of the organics in the particles during their growth from sizes of a few nanometers to tens of nanometers was derived from measured hygroscopicity assuming the Zdanovskii–Stokes–Robinson relationship, and compared to values gained from the spectrometers. The ZSR-relationship was also applied to obtain the measured ethanol affinities during the particle growth, which were used to derive the volume fractions of sulphuric acid and the other inorganics (e.g. ammonium salts). In the presence of sulphuric acid and ammonia, particles with a mobility diameter of 150 nm were chemically neutralised to ammonium sulphate. In the presence of oxidation products of pinanediol, the organic volume fraction of freshly nucleated particles increased from 0.4 to ~0.9, with an increase in diameter from 2 to 63 nm. Conversely, the sulphuric acid volume fraction decreased from 0.6 to 0.1 when the particle diameter increased from 2 to 50 nm. The results provide information on the composition of nucleated aerosol particles during their growth in the presence of various combinations of sulphuric acid, ammonia, dimethylamine and organic oxidation products

Simple Mercury Fractionation In Biological Samples By Cv Aas Following Microwave-assisted Acid Digestion Or Tmah Pre-treatment

A simple and reliable method to determine total and inorganic mercury in biological certified reference material (CRM) by cold vapor atomic absorption spectrometry (CV AAS) is proposed. After the CRM treatment at room temperature with tetramethylammonium hydroxide (TMAH), inorganic mercury is determined by CV AAS. Total mercury is measured by the same technique, after sample acid digestion in a microwave oven. Organic mercury, basically methylmercury, is obtained by difference. In both procedures, the quartz tube is kept at room temperature. By means of analysis of the following reference materials: pig kidney, lobster hepatopancreas, dogfish liver and mussel tissue, it was clear that the difference between the total and inorganic mercury concentrations agrees with the methylmercury concentration. Only one calibration curve against aqueous standards in acidic medium was carried out for both procedures. The concentrations obtained by both procedures are in agreement with the certified values according to the t-test at a 95% confidence level. The relative standard deviations were lower than 3.0% for digested CRM and 6.0% for CRM treated with TMAH for most of the samples. The limits of detection in the samples were 0.02 μg g- 1 and 0.04 μg g- 1 for inorganic and total Hg, respectively, since the sample mass for total mercury was half of that for inorganic mercury determination. Simplicity and high efficiency without using chromatographic techniques are some of the qualities of the proposed method, being adequate for fractionation analysis of mercury in biological samples. © 2009 Elsevier B.V. All rights reserved.932206210Azevedo, F.A., (2003) Toxicologia do mercúrio, RiMa, São CarlosKaercher, L.E., Goldschmidt, F., Paniz, J.N.G., Flores, É.M.M., Dressler, V.L., Determination of inorganic and total mercury by cold vapor generation atomic absorption spectrometry using different temperatures of the measurement cell (2005) Spectrochim. Acta Part B, 60, pp. 705-710Vieira, M.A., Ribeiro, A.S., Curtius, A.J., Sturgeon, R.E., Determination of total and methylmercury in biological samples by photochemical vapor generation (2007) Anal. Bioanal. Chem., 388, pp. 837-847Tao, G., Willie, S.N., Sturgeon, R.E., Determination of total mercury in biological tissues by flow injection cold vapour generation atomic absorption spectrometry following tetramethylammonium hydroxide digestion (1998) Analyst, 123, pp. 1215-1218Welz, B., Sperling, M., (1999) Atomic Absorption Spectrometry. third ed., , Wiley-VCH, WeinheimTsalev, D., Sperling, M., Welz, B., On-line microwave sample pre-treatment for hydride generation and cold vapour atomic absorption spectrometry. Part 1. The manifold (1992) Analyst, 117, pp. 1729-1733Tsalev, D., Sperling, M., Welz, B., On-line microwave sample pre-treatment for hydride generation and cold vapour atomic absorption spectrometry. Part 2. Chemistry and applications (1992) Analyst, 117, pp. 1735-1741Tinggi, U., Craven, G., Determination of total mercury in biological materials by cold vapor atomic absorption spectrometry after microwave digestion (1996) Microchem. J., 54, pp. 168-173Rezende, M.C.R., Campos, R.C., Curtius, A.J., Speciation of mercury in fish samples by solvent extraction, methyl-mercury reduction directly in the organic medium and cold vapour atomic absorption spectrometry (1993) J. Anal. At. Spectrom., 8, pp. 247-251Matusiewicz, H., Golik, B., Determination of major and trace elements in biological materials by microwave induced plasma optical emission spectrometry (MIP-OES) following tetramethylammonium hydroxide (TMAH) solubilization (2004) Microchem. J., 76, pp. 23-29Tao, G., Willie, S.N., Sturgeon, R.E., Determination of inorganic mercury in biological tissues by cold vapor atomic absorption spectrometry following tetramethylammonium hydroxide solubilization (1999) J. Anal. At. Spectrom., 14, pp. 1929-1931Willie, S.N., Grégoire, D.C., Sturgeon, R.E., Determination of inorganic and total mercury in biological tissues by electrothermal vaporization inductively coupled plasma mass spectrometry (1997) Analyst, 122, pp. 751-754Jimenez, M.S., Sturgeon, R.E., Speciation of methyl- and inorganic mercury in biological tissues using ethylation and gas chromatography with furnace atomization plasma emission spectrometric detection (1997) J. Anal. At. Spectrom., 12, pp. 597-601Torres, D.P., Vieira, M.A., Ribeiro, A.S., Curtius, A.J., Determination of inorganic and total mercury in biological samples treated with tetramethylammonium hydroxide by cold vapor atomic absorption spectrometry using different temperatures in the quartz cell (2005) J. Anal. At. Spectrom., 20, pp. 289-294Serafimovski, I., Karadjova, I., Stafilov, T., Cvetkovic, J., Determination of inorganic and methylmercury in fish by cold vapor atomic absorption spectrometry and inductively coupled plasma atomic emission spectrometry (2008) Microchem. J., 89, pp. 42-47Yang, L., Mester, Z., Sturgeon, R.E., Determination of methylmercury in fish tissues by isotope dilution SPME-GC-ICP-MS (2003) J. Anal. At. Spectrom., 18, pp. 431-436Leermakers, M., Baeyens, W., Quevauviller, P., Horvat, M., Mercury in environmental samples: speciation, artifacts and validation (2005) Trends in Anal. Chem., 24, pp. 383-393Krivan, V., Haas, H.F., Prevention of loss of mercury(II) during storage of dilute solutions in various containers (1988) Fresenius Z. Anal. Chem., 332, pp. 1-6Parker, J.L., Bloom, N.S., Preservation and storage techniques for low-level aqueous mercury speciation (2005) Sci. Total Environ., 337, pp. 253-263Santos, E.J., Herrmann, A.B., Frescura, V.L.A., Sturgeon, R.E., Curtius, A.J., A novel approach to cold vapor generation for the determination of mercury in biological samples (2008) J. Braz. Chem. Soc., 19, pp. 929-934Ribeiro, A.S., Vieira, M.A., Curtius, A.J., Slurry sampling for Hg determination in sediments, sewage sludge and coal samples by cold vapor atomic absorption spectrometry (2004) J. Braz. Chem. Soc., 15, pp. 825-831Skoog, D.A., West, D.M., Holler, F.J., Crouch, S.R., (2004) Fundamentals of Analytical Chemistry. seventh ed., , Thomson, Belmon

Determination Of Mercury In Gasoline Diluted In Ethanol By Gf Aas After Cold Vapor Generation, Pre-concentration In Gold Column And Trapping On Graphite Tube

A simple method for the determination of mercury in gasoline samples diluted with ethanol by graphite furnace atomic absorption spectrometry (GF AAS) after cold vapor (CV) generation, pre-concentration in a gold column and trapping on a graphite tube is proposed. The methodology is based upon conventional analytical processes that can be performed by any laboratory with a chemical generation and gold amalgamation systems coupled to the atomic absorption spectrometer. The GF AAS temperature was optimized, being the retention, pyrolysis and atomization temperatures, respectively, 100°C, 150°C and 800°C. Gasoline samples were prepared simply by forming a 2-fold diluted solution in ethanol. The mercury formed vapors by reacting the sample with the reducing agent were pre-concentrated in a gold column and further retained on a graphite tube, coated with gold as permanent modifier. Five samples from different gas stations around the UFSC Campus (Florianópolis, Brazil) were analyzed and the Hg concentrations were found to be in the range from 0.40μgL-1 to 0.90μgL-1. Calibration against aqueous standard solutions in acidic medium was carried out. The standard solutions had about the same viscosity as the gasoline diluted in ethanol. The relative standard deviations were lower than 2.4% for the samples. The limits of detection in the samples were 0.08 and 0.14μgL-1, with and without pre-concentration in the gold column, respectively. The accuracy of the method was estimated by applying the recovery test and recovery values between 92 and 100% were obtained. A sample throughput of 4h-1 was achieved. Simplicity and high detection capability are some of the qualities of the method. © 2010 Elsevier B.V.9613236Saint'Pierre, T.D., Dias, L.F., Maia, S.M., Curtius, A.J., Determination of Cd, Cu, Fe, Pb and Tl in gasoline as emulsion by electrothermal vaporization inductively coupled plasma mass spectrometry with analyte addition and isotope dilution calibration techniques (2004) Spectrochim. Acta. Part B., 59, pp. 551-558Brandão, G.P., Campos, R.C., Luna, A.S., Determination of mercury in gasoline by cold vapor atomic absorption spectrometry with direct reduction in microemulsion media (2005) Spectrochim. Acta. Part B., 60, pp. 625-631Wilheim, S.M., Bloom, N., Mercury in petroleum (2000) Fuel Process. Technol., 63, pp. 1-27Saint'Pierre, T.D., Dias, L.F., Pozebon, D., Aucélio, R.Q., Curtius, A.J., Welz, B., Determination of Cu, Mn, Ni and Sn in gasoline by electrothermal vaporization inductively coupled plasma mass spectrometry, and emulsion sample introduction (2002) Spectrochim. Acta. Part B., 57, pp. 1991-2001Liang, L., Horvat, M., Fajon, V., Prosenc, N., Li, H., Pang, P., Comparison of improved combustion/trap technique to wet extraction methods for determination of mercury in crude oil and related products by atomic fluorescence (2003) Energy Fuels, 17, pp. 1175-1179Bloom, N.S., Analysis and stability of mercury speciation in petroleum hydrocarbons (2000) Fresenius' J. Anal. Chem., 366, pp. 438-443Liang, L., Horvat, M., Danilchik, P., A novel analytical method for the determination of pictogram levels of total mercury in gasoline and other petroleum based products (1996) Sci. Total Environ., 187, pp. 57-64Kelly, W.R., Long, S.E., Mann, J.L., Determination of mercury in SRM crude oil and refined products by isotope dilution cold vapor ICP-MS using closed-system combustion (2003) Anal. Bioanal. Chem., 376, pp. 753-758dos Santos, W.N.L., Dias, F., Reboucas, M.V., Pereira, M., Pereira, M., Teixeira, L.S.G., Mercury determination in petroleum products by electrothermal atomic absorption spectrometry after in situ preconcentration using multiple injections (2006) J. Anal. At. Spectrom., 21, pp. 1327-1330Cassela, R.J., Barbosa, B.A.R.S., Santelli, R.E., Rangel, A.T., Direct determination of arsenic and antimony in naphta by electrothermal atomic absorption spectrometry with microemulsion sample introduction and iridium permanent modifier (2004) Anal. Bioanal. Chem., 379, pp. 66-71Chang, Y.T., Jiang, S.J., Determination of As, Cd and Hg in emulsified vegetable oil by flow injection chemical vapour generation inductively coupled plasma mass spectrometry (2008) J. Anal. At. Spectrom., 23, pp. 140-144Rivaro, P., Ianni, C., Soggia, F., Frache, R., Mercury speciation in environmental samples by cold vapour atomic absorption spectrometry with in situ preconcentration on a gold trap (2007) Microchim. Acta., 158, pp. 345-352Welz, B., Sperling, M., (1999) Atomic Absorption Spectrometry, , WILEY-VCH, Weinheim, GermanyConaway, C.H., Mason, R.P., Steding, D.J., Flegal, A.R., Estimate of mercury emission from gasoline and diesel fuel consumption, San Francisco Bay area, California (2005) Atmos. Environ., 39, pp. 101-105Won, J.H., Park, J.Y., Lee, T.G., Mercury emissions from automobiles using gasoline, diesel and LPT (2007) Atmos. Environ., 41, pp. 7547-7552Flores, E.M.M., Welz, B., Curtius, A.J., Determination of mercury in mineral coal using cold vapor generation directly from slurries, trapping in a graphite tube, and electrothermal atomization (2001) Spectrochim. Acta. Part B., 56, pp. 1605-161

Local And Temporal Variations In Essential Elements And Agar Of The Marine Algae Pterocladia Capillacea

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The concentrations of B, Ca, Co, Cu, Fe, K, Mg, Mn, Na, P, Zn and agar were determined in samples of the red alga, Pterocladia capillacea, collected during one year in three distinct locations having different hydrologic characteristics, close to the city of Arraial do Cabo, Rio de Janeiro, Brazil. Pattern recognition methods showed that, although these concentrations are subject to temporal variations, they are more dependent on the location from which the samples were collected. Algae from locations with high human activity were richer in P, B, Co, Zn and agar than those from other locations. © 1990 Kluwer Academic Publishers.1942143148FAPESP; São Paulo Research FoundationFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Determination Of Trace Elements In Liquid Aspartame Sweeteners By Icp Oes And Icp-ms Following Acid Digestion

In order to determine inorganic constituents and contaminants in liquid aspartame sweeteners, different brands of this product were analyzed by ICP OES and ICP-MS. The samples were submitted to acid digestion and parameters such as internal standardization and wavelengths, in the case of ICP OES, and a recovery test were evaluated. The analytes studied were As, Ca, Cd, Co, Cu, K, Fe, Mg, Mn, Na, Ni, Pb, Se and Zn. Since there is not a certified reference material for sweeteners, the accuracy of the proposed method was evaluated by recovery tests and the values were in the range of 90-110% for the majority of the analytes. The detection limits for the elements determined by ICP OES were in the range 0.01 (Mn)- 2.0 (K) μg g-1 while those determined by ICP-MS were 0.001 μg g-1 for all the elements except Mn and As (0.002 μg g-1). The relative standard deviations were below 12% for ICP OES and below 14% for ICP-MS determinations. The mean concentration of the elements detected by ICP OES (Ca, Fe, K, Mg, Na, and Zn) varied according to the brand. The other analytes, were determined by ICP-MS. For these elements, a significant variation in their concentrations was also found for different samples, except for Co and Ni. The use of both multielemental techniques allowed the evaluation of the inorganic composition and the rapid determination of several elements in aspartame sweeteners, with adequate accuracy. © 2007 Springer-Verlag.15903/04/15241246Henin, N., Intake of sweeteners, physiological and nutritional aspects (2001) Int Sugar J, 103, p. 346Mitchell, H., Dedman, J., Garman, C., Alternative sweeteners: Finding the correct technical and nutritional balance (2001) Int Sugar J, 103, p. 324Kretchmer, N., Hollenbeck, C.B., (1991) Sugars and Sweeteners, p. 17. , CRC Press Boca RatonGerhartz, W., (1985) Ullmann's Encyclopedia of Industrial Chemistry, p. 573. , 5 A11 VCH New YorkJost, R., Monti, J.C., Schauhelberger, U., Analysis of the dipeptide sweetener aspartame (1982) Int J Vitam Nutr Res, 52, p. 229Sales, J.A., Cardeal, Z.D., Headspace solid-phase micro-extraction gas chromatography method for the determination of methanol in aspartame sweeteners (2003) Food Add Cont, 20, p. 519Saurina, J., Hlabangana, L., García-Milla, D., Hernández-Cassou, S., Flow-injection determination of amine contaminants in cyclamate samples based on temperature for controlling selectivity (2004) Analyst, 129, p. 468Sousa, R.A., Baccan, N., Cadore, S., Analysis of liquid stevioside and cyclamate-saccharin dietetic sweeteners by inductively coupled plasma optical emission spectrometry without sample preparation (2006) J Braz Chem Soc, 17, p. 1393Montaser, A., Golightly, D.W., (1992) Inductively Coupled Plasmas in Analytical Atomic Spectrometry, p. 262. , 2 VHC New YorkNóbrega, J.A., Gelinas, Y., Krushvska, A., Barnes, R.M., Direct determination of major and trace elements in milk by inductively coupled plasma atomic emission and mass spectrometry (1997) J Anal Atom Spectrom, 12, p. 1243Miller-Ihli, N.J., Baker, S.A., Trace element composition of municipal waters in the United States: A comparison of ICP-AES and ICP-MS methods (2001) J Food Comp Anal, 14, p. 619Jarvis, K.E., Gray, A.L., Houk, R.S., (1996) Inductively Coupled Plasma Mass Spectrometry, p. 180. , Blackie Academic & Professional LondonNóbrega, J.A., Santos, M.C., Sousa, R.A., Cadore, S., Barnes, R., Tatro, M., Sample preparation in alkaline medium (2006) Spectrochim Acta B, 61, p. 465Sousa, R.A., Baccan, N., Cadore, S., Direct determination of metals in Brazilian coconut water utilizing an inductively coupled plasma optical emission spectrometer (2005) J Braz Chem Soc, 16, p. 540Silva, J.C.J., Santos, D.M., Cadore, S., Nóbrega, J.A., Baccan, N., Evaluation of inductively coupled plasma optical emission spectrometers with axial configuration in organic medium: Interfaces with end-on gas and shear gas (2004) Microchem J, 77, p. 185Boss, C.B., Fredeen, K.J., (1999) Concepts, Instrumentation and Techniques in Inductively Coupled Plasma Optical Emission Spectrometry, p. 48. , 2 Perkin-Elmer Corp NorwalkSousa, R.A., Silva, J.C.J., Baccan, N., Cadore, S., Direct determination of metals in bottled Brazilian coconut water using a double-view inductively coupled plasma optical emission spectrometer (2005) J Food Comp Anal, 18, p. 399Brenner, I.B., Zander, A.T., Axially and radially viewed inductively coupled plasmas - A critical review (2000) Spectrochim Acta B, 55, p. 1195McKinstry, P.J., Indyk, H.E., Kim, N.D., The determination of major and minor elements in milk and infant formula by slurry nebulisation and inductively coupled plasma-optical emission spectrometry (ICP-OES) (1999) Food Chem, 65, p. 245Jenniss, S.W., Katz, A.S., Lynch, R.W., (1997) Applications of Atomic Spectrometry to Regulatory Compliance Monitoring, p. 15. , 2 Wiley-VHC New Yorkhttp://e-legis.bvs.br/leisref/public/showAct.php?id=90&mode= PRINT_VERSION, accessed in August 2006http://www.codexalimentarius.net/web/stand;CAC/GL39-2001, accessed in August 2006http://www.codexalimentarius.net/web/stand;CODEXSTAN210-2001, accessed in August 200

A Comparative Study Of Homemade C18 And Commercial C 18 Sorbents For Preconcentration Of Lead By Minicolumn Solid Phase Extraction

A comparative study of commercial C18 chemically immobilized on silica and homemade C18, as sorbents for Pb complexed with O,O-diethyl-dithiophosphate (DDTP) in a flow injection preconcentration system is reported. The homemade C18 sorbent was obtained by sorption of poly(methyloctadecylsiloxane) (PMODS) on the silica support followed by immobilization using thermal treatment. The method follows the concept of green chemistry, since there are no toxic residues after synthesis. The complexed Pb was formed in 1.0∈mol∈L-1 HCl medium and retained on the minicolumn filled with the sorbents. The elution was carried out using ethanol, and the richest 210∈μL fraction was collected and analyzed by flame atomic absorption spectrometry. Chemical and flow variables were optimized for each sorbent. The results demonstrated that the performance of the proposed homemade C18 sorbent for preconcentration of Pb complexed with DDTP is very similar to commercial C18 chemically bonded on silica. By processing 25∈mL, the enrichment factors were 129 and 125 for commercial C18 and homemade C18, respectively. The limit of detection for commercial and homemade C18 was 0.2∈μg∈L -1 and 0.6∈μg∈L-1, respectively. The relative standard deviation (RSD) was lower than 1.2% for both sorbents for a Pb concentration of 100∈μg∈L-1. The method was also applied successfully to the analysis of water samples, and the accuracy was tested by recovery measurements on spiked samples and biological reference material. © Springer-Verlag 2003.1441-31721Ruzicka, J., Arndal, A., (1989) Anal Chim Acta, 2, pp. 243-255Xu, S.K., Sperling, M., Welz, B., (1992) Frezenius J Anal Chem, 64, pp. 3101-3108Bertoli, A., Gerotto, M., Marchiori, M., Mariconti, F., Palonta, M., Troncon, A., (1996) Microchem J, 54, pp. 402-411Iyer, C.S.P., Rao, T.P., Kartikeyan, T., Damodaran, A.D., (1994) At Spectrosc, 15, pp. 234-236Tony, K.A., Kartikeyan, S., Vijayalaksshmy, B., Rao, T.P., Iyer, C.S.P., (1999) Analyst, 134, pp. 191-195Kartikeyan, S., Vijayalaksshmy, B., Chandramoulesswaran, S., Rao, T.P., Iyer, C.S.P., (1997) Anal Lett, 30, pp. 1037-1050Ali, A., Yin, X.F., Shen, H., Ye, Y.X., Gu, X., (1999) Anal Chim Acta, 392, pp. 283-289Sella, S.M., Avila, A.K., Campos, R.C., (1999) Anal Lett, 32, pp. 2091-2104Quináia, S.P., Da Suva, J.B.B., Rollemberg, M.C.E., Curtius, A.J., (2001) Talanta, 54, pp. 687-696Ivanova, E., Van Mol, W., Adams, F., (1998) Spectrochimica Acta B, 53, pp. 1041-1048Akapo, S.O., Dimandja, J.M.D., Matyska, M.T., Pesek, J.J., (1996) J Microcol Sep, 42, pp. 189-200Nawrocki, J., Dabrowska, A., (2000) J Chromatogr A, 868, pp. 1-12Melo, L.F.C., Jardim, I.C.S.F., (1999) J Chromatogr A, 845, pp. 423-431Melo, L.F.C., Collins, C.H., Collins, K.E., Jardim, I.C.S.F., (2000) J Chromatogr A, 869, pp. 129-135Gushikem, Y., Rosatto, S.S., (2001) J Braz Chem Soc, 12, pp. 695-705Silva, R.B., Collins, C.H., (1999) J Chromatogr A, 845, pp. 417-422Jardim, I.C.S.F., Collins, K.E., Anazawa, T.A., (1999) J Chromatogr A, 849, pp. 299-307Bachmann, S., Melo, L.F.C., Suva, R.B., Anazawa, T.A., Jardim, I.C.S.F., Collins, K.E., Collins, C.H., Albert, K., (2001) Chem Mater, 13, pp. 1874-1879Tonhi, E., Bachmann, S., Albert, K., Jardim, I.C.S.F., Collins, K.E., Collins, C.H., (2002) J Chromatogr A, 97, pp. 97-107Tonhi, E., Collins, K.E., Collins, C.H., (2002) J Chromatogr A, 948, pp. 109-119Queiroz, S.C.N., Melo, L.F.C., Jardim, I.C.S.F., (2002) J Chromatogr A, 948, pp. 171-176Carasek, E., (2000) Talanta, 51, pp. 173-178Pozzebon, J.M., Queiroz, S.C.N., Melo, L.F.C., Kapor, M.A., Jardim, I.C.S.F., (2003) J Chromatogr A, 987, pp. 381-38

Determination of total and inorganic mercury in whole blood by cold vapor inductively coupled plasma mass spectrometry (CV ICP-MS) with alkaline sample preparation

A simple method with a fast sample preparation procedure for total and inorganic mercury determinations in blood samples is proposed based on flow injection cold vapor inductively coupled plasma mass spectrometry (FI-CV ICP-MS). Aliquots of whole blood (500 L) are diluted 1 + 1 v/v with 10.0% v/v tetramethylammonium hydroxide (TMAH) solution, incubated for 3 h at room temperature and then further diluted 1 + 4 v/v with 2.0% v/v HCl. The inorganic Hg was released by on-line addition of L-cysteine and then reduced to elemental Hg by SnCl2. On the other hand, total mercury was determined by on-line addition of KMnO4 and then reduced to elemental Hg by NaBH4. Samples were calibrated against matrix-matching. The method detection limit was found to be 0.80 g L-1 and 0.08 g L-1 for inorganic and total mercury, respectively. Sample throughput is 20 samples h-1. The method accuracy is traceable to Standard Reference Material (SRM) 966 Toxic Metals in Bovine Blood from the National Institute of Standards and Technology (NIST). For additional validation purposes, human whole blood samples were analyzed by the proposed method and by an established CV AAS method, with no statistical difference between the two techniques at 95% confidence level on applying the t-test.24101414142