Ewa Dabek-Zlotorzynska

Analysis of the Unresolved Organic Fraction in Atmospheric Aerosols with Ultrahigh-Resolution Mass Spectrometry and Nuclear Magnetic Resonance Spectroscopy: Organosulfates As Photochemical Smog Constituents†

Complementary molecular and atomic signatures obtained from Fourier transform ion cyclotron resonance (FTICR) mass spectra and NMR spectra provided unequivocal attribution of CHO, CHNO, CHOS, and CHNOS molecular series in secondary organic aerosols (SOA) and high-resolution definition of carbon chemical environments. Sulfate esters were confirmed as major players in SOA formation and as major constituents of its water-soluble fraction (WSOC). Elevated concentrations of SO(2), sulfate, and photochemical activity were shown to increase the proportion of SOA sulfur-containing compounds. Sulfonation of CHO precursors by means of heterogeneous reactions between carbonyl derivatives and sulfuric acid in gas-phase photoreactions was proposed as a likely formation mechanism of CHOS molecules. In addition, photochemistry induced oligomerization processes of CHOS molecules. Methylesters found in methanolic extracts of a SOA subjected to strong photochemical exposure were considered secondary products derived from sulfate esters by methanolysis. The relative abundance of nitrogen-containing compounds (CHNO and CHNOS series) appeared rather dependent on local effects such as biomass burning. Extensive aliphatic branching and disruption of extended NMR spin-systems by carbonyl derivatives and other heteroatoms were the most significant structural motifs in SOA. The presence of heteroatoms in elevated oxidation states suggests a clearly different SOA formation trajectory in comparison with established terrestrial and aqueous natural organic matter.

Capillary electrophoresis: the state-of-the-art in metal speciation studies

An overview of the state-of-the-art of capillary electrophoresis (CE) for metal speciation analysis is presented. Various CE separation approaches and detection modes applied are discussed. A comprehensive description of reported methods to date in CE speciation studies of individual metals in different oxidation states, metal complexes with inorganic and organic ligands, oxoanions and organometallic compounds is demonstrated. The potential of CE for characterisation of metal interactions with large molecules like humic substances and proteins is also described. Several examples are presented to demonstrate CEs ability to solve real-world speciation problems. Further, the current strengths and limitations of CE with regard to speciation studies are discussed. The performance of CE is also critically evaluated in relationship to conventional chromatographic techniques used in metal speciation determination.

Application of capillary electrophoresis in atmospheric aerosols analysis : determination of inorganic and organic anions

The usefulness of capillary electrophoresis in the analysis of inorganic and organic anions in atmospheric aerosols was investigated. Various electrolytes based on chromate, pyromellitate (PMA), phthalate and 2,6-naphthalenedicarboxylate (NDC) were tested. Two separate electrolyte systems (PMA and NDC) are recommended for determination of anions with different mobility. Results obtained by parallel analysis of sulphate by capillary electrophoresis and ion chromatography in atmospheric aerosols are presented.

Determination of dimethylamine and other low-molecular-mass amines using capillary electrophoresis with laser-induced fluorescence detection

The potential of capillary electrophoresis (CE) with laser-induced fluorescence (LIF) detection for the separation and determination of dimethylamine (DMA) and other low-molecular-mass amines involving precolumn derivatization with fluorescein isothiocyanate isomer I (FITC) was investigated. Different variables that affect derivatization (pH, FITC concentration, reaction time and temperature) and separation (buffer concentration, addition of various organic modifiers, applied voltage and length of capillary) were studied. The linearity, reproducibility and reliability of the method were evaluated. The estimated instrumental detection limit for a 2-s pressure injection of the FITC-DMA derivative was 50 pg/ml (10(-9) M), using LIF detection with excitation and emission wavelengths of 488 nm and 520 nm, respectively. However, for practical reasons, a minimum of 5 ng/ml DMA should be subjected to the derivatization. The applicability of the described method to the extract of atmospheric aerosol samples was demonstrated.

Temporal and spatial relationships in fine particle strong acidity, sulphate, PM1O, and PM2.5 across multiple canadian locations

The Canadian Acid Aerosol Measurement Program (CAAMP) was established in 1992 to gain a better understanding of the atmospheric behaviour of fine particle strong acidity (“acid aerosols”) and to facilitate an assessment of the potential health risks associated with acid aerosols and particles in general. During 1992. 1993 and 1994, annular denuder and filter measurements were taken at four sites in Ontario, two in Quebec, three in the Atlantic Provinces and one in the greater Vancouver area. Mean fine particle sulphate concentrations (SO42−) were highest in southern Ontario (annual average ranged from 40–70 nmol m−3), lowest at a site in the Vancouver area (average = 16 nmol m−3) and second lowest in rural Nova Scotia. However, mean fine particle strong acid concentrations (H+) were geographically different. The highest mean concentrations were at the east coast sites (annual average of up to 30 nmol m−3). Acidities were lower in areas where the fine particle acidity experienced greater neutralization from reaction with ammonia. This included the major urban centres (i.e. Toronto and Montreal) and areas with greater amounts of agricultural activity, as in rural southern Ontario. On average, ambient concentrations of fine and coarse particle mass were larger in the urban areas and also in areas where SO42− levels were higher. All the particle components were episodic. However, compared to SO42− and fine particles (PM2.5 or PM2.1, depending upon inlet design), episodes of H+ tended to be less frequent and of shorter duration, particularly in Ontario. Saint John, New Brunswick, had the highest mean annual H+ concentration, which was 30 nmol m−3. H+ episodes (24 h concentration > 100 nmol m−3) were also the most frequent at this location. The high levels in Saint John were partially due to local sulphur dioxide sources and heterogeneous chemistry occurring in fog, which, on average, led to a 50% enhancement in sulphate, relative to upwind conditions. There was a substantial amount of intersite correlation in the day to day variations in H+, SO42− , PM2.5 and PM10 (fine + coarse particles) concentrations, which is due to the influence of synoptic-scale meteorology and the relatively long atmospheric lifetime of fine particles. Sulphate was the most regionally homogenous species. Pearson correlation coefficients comparing SO42− between sites ranged from 0.6 to 0.9, depending on site separation and lag time. In many cases, particle episodes were observed to move across the entire eastern portion of Canada with about a two-day lag between the SO42− levels in southern Ontario and in southern Nova Scotia.

Further improvements in the application of high-performance liquid chromatography, capillary electrophoresis and capillary electrochromatography to the analysis of algal toxins in the aquatic environment

The presence of algal toxins in the aquatic environment represents an important socioeconomic concern in many places worldwide, due to the toxicity that these compounds can induce in seafood or freshwater organisms at very low levels. Several analytical alternatives have been proposed over the last years for the control of these contaminants, which acute or chronic toxicity requires low detection levels and demands for the search of sensitive methods for their detection and determination. HPLC has been widely used for this purpose, although several alternatives such as CE or capillary electrochromatography (CEC) are being lately developed with this aim. In this work we report on the application of improved HPLC, as well as CE and CEC, for the analysis of diarrhetic shellfish poisoning toxins, amnesic shellfish poisoning (ASP) toxins and microcystins (MCs) present in different matrices such as water, shellfish or algae. Improvements in sample preparation for increasing sensitivity and selectivity are also shown. While UV and fluorimetric detection are the detection methods generally used, mass spectrometric detection was also applied for ASP toxins and MCs, especially for confirmatory purposes. From the results obtained it can be concluded that both HPLC and CE offer a good potential for a sensitive and selective determination of these algal toxins in such complex matrices. The results obtained for CEC allow also to conclude that this technique can result in a promising technique for such application.

Recent advances in capillary electrophoresis and capillary electrochromatography of pollutants.

Recent advances in capillary electrophoresis (CE) and capillary electrochromatography (CEC) separation, detection and sample preparation methodologies applied for the determination of a variety of pollutants is overviewed. The reviewed literature illustrates the wide range of CE applications, indicating the continuing interest in CE and CEC in the environmental field.

Inorganic environmental analysis by capillary electrophoresis

a Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Kosygin Str. 19, 117975 Moscow, Russian Federation b Analysis and Air Quality Division, Environmental Technology Centre, Environment Canada, 3439 River Road, Ottawa, ON K1A OH3, Canada c Laboratory of Inorganic Analytical Chemistry, National Institute of Public Health and the Environment, P.O. Box 1, 3720 BA Bilthoven, The Netherlands

Capillary zone electrophoresis with indirect UV detection of organic anions using 2,6-naphthalenedicarboxylic acid

2,6-Naphthalenedicarboxylic acid (NDC) was characterized as a carrier electrolyte for a separation of organic anions by capillary zone electrophoresis (CZE) with indirect UV detection. Parameters which influence CZE separations such as concentration of NDC, electrolyte pH and various electroosmotic flow modifiers were investigated. The sensitivity obtained with the NDC electrolyte was five times higher than with phthalate, which is commonly used for the separation of organic anions. This method was applied to the determination of organic anions in the ambient air.

Windsor, Ontario Exposure Assessment Study: Design and Methods Validation of Personal, Indoor, and Outdoor Air Pollution Monitoring

ABSTRACT The Windsor, Ontario Exposure Assessment Study evaluated the contribution of ambient air pollutants to personal and indoor exposures of adults and asthmatic children living in Windsor, Ontario, Canada. In addition, the role of personal, indoor, and outdoor air pollution exposures upon asthmatic childrens respiratory health was assessed. Several active and passive sampling methods were applied, or adapted, for personal, indoor, and outdoor residential monitoring of nitrogen dioxide, volatile organic compounds, particulate matter (PM; PM ≤ 2.5 μm [PM2.5] and ≤ 10 μm [PM10] in aerodynamic diameter),elemental carbon, ultrafine particles, ozone, air exchange rates, allergens in settled dust, and particulate-associated metals. Participants completed five consecutive days of monitoring during the winter and summer of 2005 and 2006. During 2006, in addition to undertaking the air pollution measurements, asthmatic children completed respiratory health measurements (including peak flow meter tests and exhaled breath condensate) and tracked respiratory symptoms in a diary. Extensive quality assurance and quality control steps were implemented, including the collocation of instruments at the National Air Pollution Surveillance site operated by Environment Canada and at the Michigan Department of Environmental Quality site in Allen Park, Detroit, MI. During field sampling, duplicate and blank samples were also completed and these data are reported. In total, 50 adults and 51 asthmatic children were recruited to participate, resulting in 922 participant days of data. When comparing the methods used in the study with standard reference methods, field blanks were low and bias was acceptable, with most methods being within 20% of reference methods. Duplicates were typically within less than 10% of each other, indicating that study results can be used with confidence. This paper covers study design, recruitment, methodology, time activity diary, surveys, and quality assurance and control results for the different methods used. IMPLICATIONS It is important to obtain data to identify any factors that can influence the relationships among personal, indoor, and outdoor concentrations for a range of air pollutants. Ensuring that the methods used are valid and comparable to reference methods used in typical air pollution, monitoring is crucial for data to be of use to regulators. These exposure data can then be used to develop risk management policies that reduce personal and indoor exposures to air pollutants.