A suite of untargeted methods has been applied for the characterization of aerosol from the Tobacco Heating System 2.2 (THS2.2), a heated tobacco product developed by Philip Morris Products S.A. and ...commercialized under the brand name
IQOS
®. A total of 529 chemical constituents, excluding water, glycerin, and nicotine, were present in the mainstream aerosol of THS2.2, generated by following the Health Canada intense smoking regimen, at concentrations ≥ 100 ng/item. The majority were present in the particulate phase (
n
= 402), representing more than 80% of the total mass determined by untargeted screening; a proportion were present in both particulate and gas-vapor phases (39 compounds). The identities for 80% of all chemical constituents (representing > 96% of the total determined mass) were confirmed by the use of authentic analytical reference materials. Despite the uncertainties that are recognized to be associated with aerosol-based untargeted approaches, the reported data remain indicative that the uncharacterized fraction of TPM generated by THS2.2 has been evaluated to the fullest practicable extent. To the best of our knowledge, this work represents the most comprehensive chemical characterization of a heated tobacco aerosol to date.
Graphical abstract
•Invasive Reed Canary offers low-cost biomass from poor soils across the globe.•Biomass is subjected to pyrolysis and thermogravimetric study.•Pyrolytic behavior and reaction mechanism of the biomass ...are described.•Reed Canary has bioenergy potential equal to well-known bioenergy crops.•Pyrolysis products are captured and characterized using FTIR and GC–MS techniques.
The present study investigates the pyrolysis kinetic and thermal behavior of Invasive Reed Canary (Phalaris arundinacea) and evaluate the potential of the biomass as a bioenergy feedstock. The biomass sample was collected from wild areas of Ontario, Canada. Thermal degradation analysis were conducted by exposing the dried and powdered biomass to four heating rates (10, 20, 30 and 40 K min-1) using a Thermogravimetric Analyzer in an inert environment. Thermal data was utilized to explain the reaction chemistry using iso-conversional models of Kissenger-Akahira-Sunose (KSA), Starink and Flynn–Wall–Ozawa (FWO). Evaluation of the kinetic parameters such as the activation energy and the pre-exponential factor illustrates the promising bioenergy potential of the biomass. Fourier-transform infrared spectroscopy and Gas chromatography techniques indicate existence of valuable pyrolysis products such as aliphatic hydrocarbons. Low cost in addition to the abundance of the biomass may facilitates the consumption of the biomass for bioenergy application in cost efficient and environmental friendly manners.
Concentrations of benzene, toluene, ethylbenzene, and xylene (BTEX) were investigated in indoor air quality of 50 beauty salons in Ardabil, Iran (2017). Ten liters of air samples were collected from ...each salons regarding the recommended method and analyzed by GC-FID for BTEX concentration. Also, structural and operational conditions of the salons were studied with a self-designed questioner. The results of this study show that the mean concentration of benzene (32.40 ± 26.38) higher than the recommended levels by Health Canada, ANSES and HKSAR. Among the BTEX, ethylbenzene (62.38 ± 32.37) has the most concentrations in the salons. Subsequently, the cancer risk values in different age groups of birth to <6, 6 to <21, and 21 to <81 for benzene (1.83 × 10−3, 2.76 × 10−4 and 1.50 × 10−4, respectively) and ethylbenzene (4.9 × 10−4, 7.30 × 10−5 and 3.52 × 10−5, respectively) for long time exposure were drastically higher than the recommended levels. The results showed that the benzene concentration is significantly influenced by the structural and operational conditions of type of ventilation system, area of the salons, the number of people in the salon, number of services in the salons, and while doing of bridal makeup.
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•BTEX concentrations in 50 beauty salons were investigated.•The mean concentration of benzene higher than guideline values (ANSES and HKSAR).•LTCR from birth to 81 old for benzene and ethylbenzene were drastically higher than guideline values.•Benzene concentration is influenced by the structural, ventilation system, area and the number of people and services in the salon.
Owing to their stability at high temperature, low biodegradation, low water solubility, and low vapor pressure, substituted diphenylamines are used as antioxidants in rubber, foamed polymers, and as ...high-temperature functional fluids (e.g., lubricants, gear oils, and hydraulic fluids). There are few existing environmental measurements of these substances in any environmental medium. In this study, a method was developed for the determination of 10 substituted diphenylamines in wastewater, biosolids, and sediments using gas chromatography-tandem mass spectrometry (GC-MS/MS). The substituted diphenylamines that were measured were two styrenated diphenylamines isomers, three di-styrenated diphenylamine isomers, tert-butyl-diphenylamine, tert-octyl-diphenylamine, di-tert-butyl-diphenylamine, tert-butyl/tert-octyl-diphenylamine, and di-tert-octyl-diphenylamine. The instrument limits of detection (LODs) and limits of quantitation (LOQs) were 0.02–0.1 and 0.06–0.3 ng mL
–1
, respectively. Target compounds were spiked into sediment, effluent water, influent water, and biosolids at the 100- and 1000-ng levels (
N
= 6). Analyte recoveries ranged from 71.5 to 117 % with relative standard deviations (RSDs) of 2.12–12.4 %. The method was applied to the analysis of influent, effluent, and biosolid samples; the sum of substituted diphenylamines were 48.1–713, 1.04–28.5 ngL
–1
, and 85.3–1184 ngg
–1
dw (median: 71.0, 7.30 ngL
–1
, and 402 ngg
–1
dw), respectively. Nine sediment samples collected in Ontario, Canada contained concentrations of the sum of substituted diphenylamines ranging from 1.55 to 897 ngg
–1
dw.
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•A combined biofilm-biochar approach for contaminant removal was evaluated.•Biotic-biochar was more effective at removing naphthenic acids vs. sterile biochar.•Evidence for enhanced ...organics removal by biotic-biochar in the presence of metals.•Greater metal sorption evident with biofilm-attached biochar.•This combined approach was more effective at removal than either independently.
This study evaluated the efficacy of using a combined biofilm-biochar approach to remove organic (naphthenic acids (NAs)) and inorganic (metals) contaminants from process water (OSPW) generated by Canada’s oil sands mining operations. A microbial community sourced from an OSPW sample was cultured as biofilms on several carbonaceous materials. Two biochar samples, from softwood bark (SB) and Aspen wood (N3), facilitated the most microbial growth (measured by protein assays) and were used for NA removal studies performed with and without biofilms, and in the presence and absence of contaminating metals. Similar NA removal was seen in 6-day sterile N3 and SB assays (>30%), while biodegradation by SB-associated biofilms increased NA removal to 87% in the presence of metals. Metal sorption was also observed, with up to four times more immobilization of Fe, Al, and As on biofilm-associated biochar. These results suggest this combined approach may be a promising treatment for OSPW.
Tris(chloropropyl) phosphate (TCPP) is an environmentally abundant organophosphate ester (OPE). TCPP is comprised of four isomers with seven possible structures, eight CAS numbers, and even more ...common names. A review of 54 studies reporting one or more TCPP isomers confirmed that the most abundant and most often reported TCPP isomer was tris(2-chloro-1-methylethyl) phosphate, also known as tris(chloroisopropyl) phosphate (TCiPP, referred to hereafter as TCPP1). Full-scan gas chromatography-mass spectrometry (GC-MS) was used to identify the other three isomers numbered here according to their elution order on a non-polar GC column (DB-5): bis(2-chloro-1-methylethyl) (2-chloropropyl) phosphate (TCPP2), bis(2-chloropropyl)(2-chloro-1-methylethyl) phosphate (TCPP3), and tris(2-chloropropyl) phosphate (TCPP4). GC with a flame ionization detector (FID) was used to identify the relative abundances of the isomers in commercially available standards with unknown isomer composition. In technical TCPP, TCPP1–4 isomers averaged 71 ± 1, 26 ± 0.4, 3 ± 0.5, and 0.1 ± 0.02%, respectively. When these percent masses are incorporated into GC-MS quantification, response factors (RFs) for TCPP1 and TCPP2 are significantly different from TCPP3 and TCPP4, indicating that the multiple RF approach is more accurate than the commonly employed single RF method. Samples from urban streams and wastewater treatment plant (WWTP) effluent from Toronto, Canada, had isomeric ratios of TCPP1/2 that were not significantly different from a technical mixture whereas rain had a significantly different ratio indicating enrichment in the more volatile TCPP1 isomer. Reporting TCPP isomers can provide insight into sources, transport, and fate of TCPP in the environment.
Graphical Abstract
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We present two novel earth observation products derived from the BESD and EMMA XCO2 products which were respectively retrieved from SCIAMACHY and GOSAT observations within the GreenHouse Gas project ...of ESA's Climate Change Initiative (GHG-CCI). These products are inferred by a Carbon Cycle Data Assimilation System (CCDAS) and consist of net and gross biosphere-atmosphere fluxes of carbon dioxide on a global 0.5° grid. As a further dataset provided by the CCI, the burnt area product developed by its Fire忌i project was used in the CCDAS to prescribe the emission component from biomass burning. The new flux products are provided with per-pixel uncertainty ranges. Fluxes with uncertainty ranges can also be provided aggregated in space and time, e.g. over given regions or as annual means. For both, posterior flux fields inferred from BESD and EMMA products, transport model simulations show reasonable agreement with the atmospheric carbon dioxide concentration observed at flask sampling stations. This means that the information provided by the terrestrial and transport models, the respective GHG ECV product, the burnt area ECV product, a product of the Fraction of Absorbed Photosynthetically Active Radiation used to drive the model, and the atmospheric flask samples is largely consistent.
The most prominent feature in the posterior net flux is the tropical source of CO2 inferred from both products. But for the EMMA product this release, especially over South America, is with 300gC/m2/year much more pronounced than for BESD. This confirms findings by a recent intercomparison of transport inversions using GOSAT data by Houweling et al. (2015). The reason for the larger net flux is increased heterotrophic respiration. For both products the posterior 2010 sink over Europe (without Russia) is in the range of a recent compilation of European flux estimates by Reuter et al. (2016b). The posterior 2010 uptake of Australia (including Oceania) inferred from the EMMA product is 1.3 ± 0.2PgC/year and appears to confirm the high sink also derived from GOSAT by Detmers et al. (2015) over a slightly different period and area. While for some regions (USA, Canada, Europe, Russia, Asia) the one standard deviation uncertainty ranges derived from BESD and EMMA do overlap, for some other regions (Brazil, Africa, Australia) this is not the case. It is not clear yet whether this is due to the uncertainty specifications in the respective products or the handling of uncertainty in the assimilation chain. Assumptions on correlation of observational uncertainty in space and time have a considerable impact on the inferred flux fields (≈ 60gC/m2/year). The effect of adding an uncertainty that approximates the error in the retrieval system is of similar size.
•Demonstrates for the first time the use of XCO2 as a data stream in a CCDAS•Finds terrestrial source in the tropics•Inferred fluxes are consistent with atmospheric flask samples.•Demonstrates the importance of uncertainty correlations in XCO2 products
Our study aimed to estimate the prevalence of heavy fetal alcohol exposure through the analysis of meconium FAEEs as an objective biomarker of fetal exposure. We conducted a study on meconium samples ...collected nationwide through the Maternal-Infant Research on Environmental Chemicals (MIREC) Study Group. FAEE in meconium was quantified by an established headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (SPME GC-MS). Out of 1315 samples collected in 10 Canadian obstetric units coast to coast between 2008-2011, the estimated prevalence of positive meconium FAEE ranged between 1.16% and 2.40%, translating into at least 1800 new cases of FASD in Canada each year. Positive maternal self- reports of heavy alcohol use were tenfold lower (0.24%). Use of meconium FAEE revealed tenfold more cases of heavy exposure to maternal drinking than did maternal reports. The use of objective measures of maternal alcohol exposure is critical in accurately estimating risks and in monitoring effective prevention of FASD.
In this study a ceiling tile (CT) was selected as a sorptive passive panel, and the effect of environmental conditions on its formaldehyde removal efficiency was evaluated. Experiments were performed ...in a 0.4 m3 chamber with the air flow rate of 0.2 m3 h−1, the air exchange rate of the 0.5 h−1, and the loading ratio of 0.23m2m-3. The range of temperature humidity levels varied between 21 °C ± 2 °C–26 °C ± 2 °C, and 30% ± 5%–75% ± 5%, respectively, to simulate the indoor conditions for Canadian homes during most months of the year. Results demonstrated formaldehyde removal efficiency between 40% and 75% depending on the applied environmental conditions. GC/MS and HPLC trace analyses revealed that only very low concentrations of by-products were formed. The by-product formation increased slightly when exposing the ceiling tile to relatively high relative humidity (RH = 75%) and temperature (T = 26 °C). Given a loading factor of only 0.23 m2 m−3in our test chamber, which in most scenarios underestimates the loading factor in real settings, our findings suggest that ceiling tiles used as passive removal panels have the potential to lower formaldehyde concentrations under the Health Canada's guideline for residential settings under real-life conditions.
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•The used sorptive ceiling tiles (CTs) significantly reduce formaldehyde concentrations in air.•In dynamic chamber experiments the CT lowers formaldehyde concentrations by 40%–75%.•The efficiency of the examined CT depends on the applied environmental conditions.•The concentrations of volatile by-products are very low, close to the detection limit.•Sorptive CTs are therefore a promising approach to better indoor air quality.
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