Aerosolomics based approach to discover source molecular markers: A case study for discriminating residential wood heating vs garden green waste burning emission sources.

Biomass burning is a significant source of particulate matter (PM) in ambient air and its accurate source apportionment is a major concern for air quality. The discrimination between residential wood heating (RWH) and garden green waste burning (GWB) particulate matter (PM) is rarely achieved. The objective of this work was to evaluate the potential of non-targeted screening (NTS) analyses using HRMS (high resolution mass spectrometry) data to reveal discriminating potential molecular markers of both sources.

Per- and polyfluoroalkyl substances (PFAS) in surface sediments: Occurrence, patterns, spatial distribution and contribution of unattributed precursors in French aquatic environments.

While perfluoroalkyl sulfonic acids (PFSAs) and perfluoroalkyl carboxylic acids (PFCAs) are ubiquitous in aquatic environments, non-targeted methods have recently revealed the presence of numerous unidentified per- and polyfluoroalkyl substances (PFAS). Besides those methods, the total oxidizable precursor (TOP) assay has proved useful to estimate the contribution of unattributed perfluoroalkyl acids precursors (pre-PFAAs). In this study, an optimized extraction method was developed to examine the spatial distribution of 36 targeted PFAS in surface sediments collected at French nationwide scale (n = 43), including neutral, anionic and zwitterionic molecules.

Ultrasound-assisted sample preparation for simultaneous extraction of anionic, cationic and non-ionic surfactants in sediment.

Despite their very wide use in various fields, knowledge concerning surfactants in environmental solid matrices is generally poor. One of the difficulties encountered in the analysis of surfactants is their very diverse physicochemical properties which require different extraction techniques. The objective of this work was therefore to develop an extraction method in sediments that allows the simultaneous analysis of anionic, cationic and non-ionic surfactants.

Emission factors and chemical characterization of particulate emissions from garden green waste burning.

This work provides an evaluation of the emission factors (EFs) of typical garden waste burning (fallen leaves and hedge trimming) in terms of particulate matter (PM), elemental and organic carbon (EC-OC) together with a detailed chemical characterization of 88 particle-bound organic species including polycyclic aromatic hydrocarbons (PAHs), levoglucosan and its isomers, lignin breakdown products (methoxyphenols), cholesterol, alkanes, polyols and sugars. Furthermore, wood-log based burning experiments have been performed to highlight key indicators or chemical patterns of both, green waste and wood burning (residential heating) sources, that may be used for PM source apportionment purposes. Two residential log wood combustion appliances, wood stove (RWS) and fireplace, under different output conditions (nominal and reduced) and wood log moisture content (mix of beech, oak and hornbeam), have been tested.

A multi-family offline SPE LC-MS/MS analytical method for anionic, cationic and non-ionic surfactants quantification in surface water.

Of the large number of emerging pollutants discharged from wastewaters into surface waters, surfactants are among those with the highest concentrations. However, few monitoring in river waters of these substances have already been performed and only on a few families, mostly anionic. This work aimed to develop a multi-family analytical strategy suitable for the quantification of low concentrations of surfactant in surface waters.

Characterizing environmental geographic inequalities using an integrated exposure assessment.

Background: At a regional or continental scale, the characterization of environmental health inequities (EHI) expresses the idea that populations are not equal in the face of pollution. It implies an analysis be conducted in order to identify and manage the areas at risk of overexposure where an increasing risk to human health is suspected. The development of methods is a prerequisite for implementing public health activities aimed at protecting populations.

Spatio-temporal assessment of pregnant women exposure to chlorpyrifos at a regional scale.

Background: The aim of this study was to use an integrated exposure assessment approach, combining spatiotemporal modeling of environmental exposure and fate of the chemical to assess the exposure of vulnerable populations. In this study, chlorpyrifos exposure of pregnant women in Picardy was evaluated at a regional scale during 1 year. This approach provided a mapping of exposure indicators of pregnant women to chlorpyrifos over fine spatial and temporal resolutions using a GIS environment.

Analytical methods for the determination of oil carryover from CNG/biomethane refueling stations recovered in a solvent.

Vehicle gas is often compressed to about 200 bar at the refueling station prior to charging to the vehicle's tank. If a high amount of oil is carried over to the gas, it may cause damage to the vehicles; it is therefore necessary to accurately measure oil carryover. In this paper, three analytical methods for accurate quantification of the oil content are presented whereby two methods are based on gas chromatography and one on FTIR.

The strength in numbers: comprehensive characterization of house dust using complementary mass spectrometric techniques.

Untargeted analysis of a composite house dust sample has been performed as part of a collaborative effort to evaluate the progress in the field of suspect and nontarget screening and build an extensive database of organic indoor environment contaminants. Twenty-one participants reported results that were curated by the organizers of the collaborative trial. In total, nearly 2350 compounds were identified (18%) or tentatively identified (25% at confidence level 2 and 58% at confidence level 3), making the collaborative trial a success.

Occurrence survey and spatial distribution of perfluoroalkyl and polyfluoroalkyl surfactants in groundwater, surface water, and sediments from tropical environments.

The occurrence and spatial distribution of 22 selected perfluoroalkyl and polyfluoroalkyl substances (PFASs) in surface water (n=75), groundwater (n=80) and surficial sediment (n=15) were investigated for the first time in the tropical areas constituted by the French Overseas Territories (French Guiana, Guadeloupe, Martinique, Mayotte and Reunion). Descriptive statistics and correlations between PFASs were evaluated through the use of specific statistical treatments to handle left-censored data ("non-detects"). PFASs were ubiquitous in these samples and detection frequencies as high as 79% for perfluorooctane sulfonate (PFOS) and 65% for perfluorooctanoate (PFOA) were reported in surface waters.

Analysis of zwitterionic, cationic, and anionic poly- and perfluoroalkyl surfactants in sediments by liquid chromatography polarity-switching electrospray ionization coupled to high resolution mass spectrometry.

A new analytical method is proposed for the determination of a wide span of fluoroalkylated surfactants (PFASs) of various chain lengths and polarities in sediments, including newly-identified compounds such as zwitterionic and cationic PFASs. Extraction conditions were optimized so as to maintain a common preparation procedure for all analytes (recovery range: 60-110%). Instrumental analysis was performed with ultra-high performance liquid chromatography coupled to Orbitrap mass spectrometry through polarity-switching electrospray ionization.

Assessment of background concentrations of organometallic compounds (methylmercury, ethyllead and butyl- and phenyltin) in French aquatic environments.

The aim of this work is to estimate background concentrations of organometallic compounds, such as tributyltin (TBT), dibutyltin (DBT), monobutyltin (MBT), triphenyltin (TPhT), diphenyltin (DPhT), monophenyltin (MPhT), methylmercury (MeHg), inorganic mercury (iHg) and diethyllead (Et2Pb) in the aquatic environment at the French national scale. Both water and sediment samples were collected all over the country, resulting in 152 water samples and 123 sediment samples collected at 181 sampling points. Three types of surface water bodies were investigated: rivers (140 sites), lakes (19 sites) and coastal water (42 sites), spread along the 11 French river basins.

PBPK modeling of the cis- and trans-permethrin isomers and their major urinary metabolites in rats.

Permethrin, a pyrethroid insecticide, is suspected to induce neuronal and hormonal disturbances in humans. The widespread exposure of the populations has been confirmed by the detection of the urinary metabolites of permethrin in biomonitoring studies. Permethrin is a chiral molecule presenting two forms, the cis and the trans isomers.

Development of liquid chromatography methods coupled to mass spectrometry for the analysis of substances with a wide variety of polarity in meconium.

Meconium is the first fecal excretion of newborns. This complex accumulative matrix allows assessing the exposure of the fetus to xenobiotics during the last 6 months of pregnancy. To determine the eventual effect of fetal exposure to micropollutants in this matrix, robust and sensitive analytical methods must be developed.

Spatial distribution and partitioning behavior of selected poly- and perfluoroalkyl substances in freshwater ecosystems: a French nationwide survey.

The spatial distribution and partitioning of 22 poly- and perfluoroalkyl substances (PFASs) in 133 selected rivers and lakes were investigated at a nationwide scale in mainland France. ΣPFASs was in the range View Article and Find Full Text PDF

Towards a generic variable column length method development strategy for samples with a large variety in polarity.

The development of a novel set-up for the sequential analysis of compounds with a large variety in polarity on HILIC and reversed-phase columns, coupled in series, is discussed. For this purpose, a commercially available ultra-high performance LC system, equipped with two switching valves is employed. The switching valves allow connecting the HILIC and reversed-phase columns either in series or in parallel to the system.

Development of a multi-residue method in a fetal matrix: analysis of meconium.

Meconium is the earliest stool of newborns. It is a complex matrix that reflects the degree of fetal exposure to environmental pollutants. To investigate exposure to xenobiotics, an analytical method was developed to identify and quantify some pesticides and their metabolites and BTEX metabolites in meconium.

A national reconnaissance for selected organic micropollutants in sediments on French territory.

To collect a large data set regarding the occurrence of organic substances in sediment, this study presents the examination of 20 micropollutants, as a national survey. The list of target compounds contains two alkylphenols, three polycyclic aromatic hydrocarbons (PAHs) not commonly included in monitoring programmes, six pesticides or metabolites, five pharmaceutical compounds, two hormones, one UV filter and bisphenol A. The selective and sensitive analytical methods, based on quick, easy, cheap, effective, rugged, and safe (QuEChERS) sample preparation followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) or gas chromatography-time-of-flight mass spectrometry (GC-ToF-MS), allow the quantification at limits comprised between 0.

Analysis of BTEX and chlorinated solvents in meconium by headspace-solid-phase microextraction gas chromatography coupled with mass spectrometry.

Meconium is the earliest stool of newborns, and is a complex matrix that reflects the degree of exposure of the fetus to xenobiotics. To investigate fetal exposure to volatile organic compounds, an analytical method was developed to identify and quantify BTEX (benzene, toluene, ethylbenzene, and o,m,p-xylene) and two chlorinated solvents (trichloroethylene and tetrachloroethylene) in meconium. Headspace-solid-phase microextraction coupled with gas chromatography-mass spectrometry was selected because it is simple, sensitive, can be automated, and requires no extensive sample preparation.

Development of an analytical strategy based on LC-MS/MS for the measurement of different classes of pesticides and theirs metabolites in meconium: application and characterisation of foetal exposure in France.

It is important to evaluate the impact of pesticides on human health because exposure to these compounds has been linked to harmful effects in many research studies. This exposure may be particularly harmful during the early stages of development (e.g.

Effects of bisphenol A on different trophic levels in a lotic experimental ecosystem.

Bisphenol A (BPA) is commonly used by manufacturers and can be found in many aquatic ecosystems. Data relative to BPA ecotoxicity are only available for studies in laboratory conditions on macro-invertebrates and fish. There is thus a lack of information for other trophic levels such as macrophytes.

A variable column length strategy to expedite method development.

A variable length method development (or VL-MD)strategy, exploiting the potential of an automatic column coupling system, is proposed and has been applied to a number of different pharmaceutical and environmental samples with a varying degree of complexity. The proposed strategy consistently produced separation methods that had at least an equally good critical pair resolution and an equally short run time to those of methods produced using commercially available MD assistance software. In some cases, the VL-MD strategy allowed the MD time to be drastically shortened from >30 h to an overnight run of only 12 h.

Evaluation of 1.0 mm i.d. column performances on ultra high pressure liquid chromatography instrumentation.

The present study focuses on the evaluation of 1.0 mm i.d.