Smoke Samples Research Articles

Hydrocarbons in particulate samples from wildfire events in central Portugal in summer 2010

In summer 2010, twenty eight (14 PM2.5 samples plus 14 samples PM2.5–10) smoke samples were collected during wildfires that occurred in central Portugal. A portable high-volume sampler was used to perform the sampling, on quartz fibre filters of coarse (PM2.5–10) and fine (PM2.5) smoke samples. The carbonaceous content (elemental and organic carbon) of particulate matter was analysed by a thermal–optical technique. Subsequently, the particulate samples were solvent extracted and fractionated by vacuum flash chromatography into three different classes of organic compounds (aliphatics, polycyclic aromatic hydrocarbons (PAHs) and carbonyl compounds). The organic speciation was performed by gas chromatography–mass spectrometry (GC–MS). Emissions were dominated by the fine particles, which represented around 92% of the PM10. A clear predominance of carbonaceous constituents was observed, with organic to elemental carbon (OC/EC) ratios ranging between 1.69 and 245 in both size fractions. The isoprenoid ketone 6,10,14-trimethyl-2-pentadecanone, a tracer for secondary organic aerosol formation, was one of the dominant constituents in both fine and coarse particles. Retene was the most abundant compound in all samples. Good correlations were obtained between OC and both aliphatic and PAH compounds. Pyrogenic processes, thermal release of biogenic compounds and secondary processing accounted for 97% of the apportioned PM2.5 levels.

Organic tracers in aerosols from the residential combustion of pellets and agro-fuels

The consumption of pellets and alternative biofuels, such as some agricultural residues, has experienced a tremendous growth in Mediterranean countries, which has changed the panorama of biomass burning emissions. To apply source apportionment models, specific chemical signatures for smoke aerosols are necessary. In this study, filter samples of fine particles (PM2.5) from the combustion of four different types of pellets and three agro-fuels (shell of pine nuts, olive pit and almond shell) in a pellet stove were collected. The PM2.5 samples were extracted with dichloromethane/methanol and the dried extracts were silylated before injection into the gas chromatograph-mass spectrometer (GC-MS). The analysis included monosaccharide anhydrides, resin acids, methoxyphenols and sterols. The amounts emitted were highly variable and dependent on both biofuel and combustion temperature. On average, the anhydrosugar particle mass fractions for the seven biofuels were 30 to 70 times lower than the values reported for manually fired systems. The highest levoglucosan emissions were observed for olive pit. Levoglucosan to mannosan ratios ranged from values around 2 for pellets and shell of pine nuts to much higher quotients, similar to those reported for hardwood combustion. Irrespective of biofuel, vanillin and vanillic acid were always present in the smoke samples. Coniferyl alcohol was only detected in samples from the combustion of olive pit and pellets with the highest softwood content. Sinapyl alcohol was exclusively emitted by olive pit. Dehydroabietic and isopimaric acids were represented in emissions whether from all type of pellets or from shell of pine nuts, whilst abietic acid was only quantifiable in PM2.5 from the combustion of pellets made of coniferous wood. Sitosterol was solely detected in smoke particles from shell of pine nuts and olive pit.

Chemical and light absorption properties of humic-like substances from biomass burning emissions under controlled combustion experiments

PM2.5 samples from biomass burning (BB) emissions of three types - rice straw (RS), pine needles (PN), and sesame stems (SS) - were collected through laboratory-controlled combustion experiments and analyzed for the mass, organic and elemental carbon (OC and EC), water-soluble organic carbon (WSOC), humic-like substances (HULIS), and water soluble inorganic species (Na+, NH4+, K+, Ca2+, Mg2+, Cl−, NO3−, SO42−, and oxalate). The combustion experiments were carried out at smoldering conditions. Water-soluble HULIS in BB samples was isolated using a one-step solid phase extraction method, followed by quantification with a total organic carbon analyzer. This study aims to explore chemical and light absorption characteristics of HULIS from BB emissions. The contributions of HULIS (=1.94 × HULIS-C) to PM2.5 emissions were observed to be 29.5 ± 2.0, 15.3 ± 3.1, and 25.8 ± 4.0%, respectively, for RS, PN, and SS smoke samples. Contributions of HULIS-C to OC and WSOC for the RS, PN, and SS burning emissions were 0.26 ± 0.03 and 0.63 ± 0.05, 0.15 ± 0.04 and 0.36 ± 0.08, and 0.29 ± 0.08 and 0.51 ± 0.08, respectively. Light absorption by the water extracts from BB aerosols exhibited strong wavelength dependence, which is characteristic of brown carbon spectra with a sharply increasing absorption as wavelength decreases. The average absorption Ångström exponents (AAE) of the water extracts (WSOC) fitted between wavelengths of 300–400 nm were 8.3 (7.4–9.0), 7.4 (6.2–8.5), and 8.0 (7.1–9.3) for the RS, PN, and SS burning samples, which are comparable to the AAE values of BB samples reported in previous publications (e.g., field and laboratory chamber studies). The average mass absorption efficiencies of WSOC measured at 365 nm (MAE365) were 1.37 ± 0.23, 0.86 ± 0.09, and 1.38 ± 0.21 m2/g⋅C for RS, PN, and SS burning aerosols, respectively. Correlations of total WSOC, hydrophilic WSOC (= total WSOC–HULIS-C), and HULIS-C concentrations in solution with the light absorption of WSOC at 365 nm indicate that the light absorption of WSOC from BB emissions was strongly associated with HULIS (R2 = 0.92) - i.e., a hydrophobic component of WSOC, rather than with the hydrophilic WSOC (R2 = 0.31).

Determination of major aroma components in mainstream cigarette smoke using cold trap followed by GC×GC-TOFMS

A qualitative and quantitative analytical method was developed and applied to the analysis of major aroma components present in mainstream tobacco smoke. The cigarette smoke samples were cold trapped using liquid nitrogen and then analysed by comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC×GC-TOFMS). Important experimental parameters, such as the type, volume of the extraction solvent, and flow rate of smoking were optimised to improve the analysis results. The results indicated that 180 mL of diethyl ether in the cold trap with a 4.0 mL·min-1 smoke flow rate were the optimal condition. Using this experimental setup, a total of 112 aroma components were identified and quantified using a mass spectral library search. Compared to the Cambridge filter pad method, a higher peak number and better repeatability were obtained using the cold trap method. The developed analytical method was applied to the classification of different cigarette styles.

Improved ninhydrin-based reagent for spectrophotometric determination of ppb levels of cyanide

ABSTRACTCyanide is an extremely severe poison that has been raising concerns and controversies regarding its toxic effects on humans and the environment. A short-term human exposure to elevated levels can induce coma or death. Toxic effects occur at blood cyanide concentrations of 0.05 mg/dL, while death can occur at levels of 0.3 mg/dL. Numerous law and systems regulate cyanide levels in various environments. To exemplify, the maximum contamination limit imposed by United States Environmental Protection Agency in drinking water is 200 µg/L, while the European Union presents a lower limit of 50 µg/L. Ninhydrin has proved to be an effective color reagent for the spectrophotometric determination of trace levels of cyanide. This article reports a ninhydrin-based color reagent that was employed in cyanide determination involving real samples of water, cigarette smoke, urine, and cyanogenic plants, achieving an appropriate sample pretreatment procedure for cyanide liberation and separation. The reaction between cyanide and ninhydrin is fast enough to be performed at ambient conditions, but the ninhydrin reagent must be freshly prepared in oxygen-free solvent. Beer's law is obeyed in the range between 20 and 400 ppb CN− (r = 0.992; N = 7) with molar absorptivity of 1.4 × 105 L mol−1 cm−1 and limit of detection of 8 ppb cyanide. Recovery at 100 ppb CN− was (100.5 ± 0.1) %, whereas precision was 1.7%. Also, absorbance at 485 nm proved to be temperature-dependent, with a maximum at ambient conditions. Throughout all measurements, the ninhydrin-based assay proved to be reliable, economical and environmentally friendly. Significance of the assay for the determination of cyanide in the field of environmental forensics, as well as its potential aid in elucidating incidents with legal consequences are highlighted.

Determination of hydroxylated polycyclic aromatic hydrocarbons by HPLC-photoionization tandem mass spectrometry in wood smoke particles and soil samples.

A simple and fast method for analysis of hydroxylated polycyclic aromatic hydrocarbons using pressurized liquid extraction and high performance liquid chromatography utilizing photoionization tandem mass spectrometry was developed. Simultaneous separation and determination of nine hydroxylated polycyclic aromatic hydrocarbons and two hydroxy biphenyls could be performed in negative mode with a run time of 12min, including equilibration in 5min. The calibration curves were in two concentration ranges; 1-50ng/mL and 0.01-50μg/mL, with coefficients of correlation R (2) > 0.997. The limits of detection and method quantification limits were in the range of 9-56pg and 5-38ng/g, respectively. A two-level full factorial experimental design was used for screening of conditions with the highest impact on the extraction. The extraction procedure was automated and suitable for a large number of samples. The extraction recoveries ranged from 70 to 102% and the matrix effects were between 92 and 104%. The overall method was demonstrated on wood smoke particles and soil samples with good analytical performance, and five OH-PAHs were determined in the concentration range of 0.19-210μg/g. As far as we know, hydroxylated polycyclic aromatic hydrocarbons were determined in wood smoke and soil samples using photoionization mass spectrometry for the first time in this present study. Accordingly, this study shows that high performance liquid chromatography photoionization tandem mass spectrometry can be a good option for the determination of hydroxylated polycyclic aromatic hydrocarbons in complex environmental samples. Graphical Abstract The method developed in this study was used to determine hydroxylated polycyclic aromatic hydrocarbons in wood smoke and soil.

Automatic cleaning system of sample preparation of flue gas tester

It is shown a detailed description of the operation of the automatic cleaning at different modes and levels of concentration of dust and gas stream pollution of flue gas. The basis of an automatic cleaning system of dust filters before gas analyzers based on the principle of a closed system of automatic control. The system constantly compares the real current flow rate with a fixed current pre-entered in the control unit. The control unit sends a signal to the switching system of solenoid valves when reducing the flow of the sample, due to contamination (clogging) of filters below a fixed level and with the help of flow booster begins to reverse blowing of dust filter from dust in the chimney. During investigation it is found that the best operation mode of system actuation is a 25-30 % decrease in the expense of the nominal value of the primary sample flow while clean filter. Another important feature of the system is the choice of performance and power of flow boosters for blowdown. The power of flow booster was 1,5-2,0 kW during investigations on the smokestacks of coal boilers, TPC with the dust concentration of 120-150 mg/m 3 with ensuring a flow rate of smoke samples in the range of 8-10 l/min. The proposed system is simple in construction, does not require a significant investment for its implementation and provides automatic cleaning of dust filters without operator. Automatic cleaning of filter dust is recommended for stationary systems for monitoring the concentration of toxic components of flue gases for industry, energy, cement, brick and asphalt concrete plants, everywhere where the treatment and control of flue gas is carried out by gas analyzers.

A health risk assessment of Arabian incense (Bakhour) smoke in the United Arab Emirates

Burning Arabian incense (Bakhour) is a common practice in the Middle East and Arabian Gulf. Although the incense generates large amounts of chemicals and air pollutants, little is known with regard to the nature of these chemicals and their potential health risks. The aim of this study is to provide a comprehensive characterization of the chemical constituents emitted in Bakhour smoke, and subsequently to examine the associated health implications of these components. Thermo-gravimetric analysis was used to investigate the presence and the thermal profile of volatile organic compounds in three different samples of Bakhour smoke. Thermal desorption–gas chromatography–mass spectrometry was then applied to isolate all the volatile and semi-volatile compounds present in the Bakhour smoke samples. Using a spectral library and an extensive literature search, all organic compounds detected were analyzed for potential health risks. A total of 859 compounds were emitted from burning the different Bakhour samples. The novel finding of this research shows that 42 detected compounds are suspected/known carcinogens, 20 are known to have toxic effects, and at least 200 compounds are known irritants to the eyes, skin, respiratory and digestive tracts, as reported in human and/or animal studies. Our study suggests that inhaled Bakhour smoke contains a substantial number of adverse compounds, which are known to be detrimental to human health. Moreover, the evidence presented shows that incense burning is a significant source of environmental pollution; with the potential of significant health concerns particularly with long term exposure. As the majority of the compounds detected have no reported clinical data, there is an urgent need for significant research in this field.

Coupling gas chromatography and electronic nose detection for detailed cigarette smoke aroma characterization

Aroma characterization of whole cigarette smoke samples using sensory panels or electronic nose (E-nose) devices is difficult due to the masking effect of major constituents and solvent used for the extraction step. On the other hand, GC in combination with olfactometry detection does not allow to study the delicate balance and synergetic effect of aroma solutes.To overcome these limitations a new instrumental set-up consisting of heart-cutting gas chromatography using a capillary flow technology based Deans switch and low thermal mass GC in combination with an electronic nose device is presented as an alternative to GC–olfactometry. This new hyphenated GC–E-nose configuration is used for the characterization of cigarette smoke aroma. The system allows the transfer, combination or omission of selected GC fractions before injection in the E-nose. Principal component analysis (PCA) and discriminant factor analysis (DFA) allowed clear visualizing of the differences among cigarette brands and classifying them independently of their nicotine content. Omission and perceptual interaction tests could also be carried out using this configuration. The results are promising and suggest that the GC–E-nose hyphenation is a good approach to measure the contribution level of individual compounds to the whole cigarette smoke.

Comparative Study of Cigarette Smoke Cytotoxicity Using Two In Vitro Assay Systems

SUMMARY The aim of this study was to compare the results obtained from two in vitro cytotoxicity assays that depend upon different mechanisms/modes of action. The Neutral Red Uptake (NRU) assay is based on endocytotic activity whereas the Water Soluble Tetrazolium Salts (WST-1) assay is based on mitochondrial dehydrogenase activity. Both were investigated in light of their wide use and documented validation. The total particulate matter (TPM) and gas vapor phase (GVP) of main stream smoke derived from Kentucky reference cigarettes 3R4F and 10 test cigarettes made of 100% flue-cured or 100% Burley tobacco were individually applied to the two assays using CHO-K1 cells. In addition, cigarette smoke constituents and known cytotoxic agents, documented to affect specific endpoints, were evaluated within both assays. Although the NRU assay was primarily more sensitive than the WST-1 assay, both assays provided comparable results in terms of the rank order for the cytotoxicity of cigarette smoke samples. In addressing the cytotoxicity of constituents in cigarette smoke, acrolein, hydroquinone and catechol gave clear dose-related decreases in cell viability (an end point common in both assays). Moreover, enzyme inhibitors of the mitochondrial respiratory chain and chemicals causing membrane disruption also showed similar responses regardless of the specific endpoint addressed within the cytotoxicity assay. In conclusion, results from the NRU and WST-1 assay are comparable therefore indicating results were independent of the different assay detection mechanisms/modes of action. [Beitr. Tabakforsch. Int. 26 (2014) 98-108]

환경담배연기로 인한 실내공기 중 PM2.5 및 미량성분 오염 특성

Environmental tobacco smoke (ETS) samples were collected separately in mainstream and side-stream smoke using a self-designed smoking machine, and a total 40 of PM2.5 was collected with low volume air sampler at indoor environments with and without ETS in Daejeon, Korea. About 20 trace elements including toxic metals like As, Cr, Mn, Se, V, and Zn were determined in PM2.5 and ETS samples by instrumental neutron activation analysis (INAA). It is found that the emission factors of K, Cl, Na, and Al were much higher than those of toxic elements for both mainstream and side-stream smoke. The average concentration of PM2.5 was enriched by 1.5 times at smoking area (58.7±18.1 µg/m 3 ) than at smoking free area (38.6±12.7 µg/m 3 ). The concentration ratio of each element between smoking and smoking free area were ranged from 1.1 to 6.0 except Cu (1.0); especially, Ce (6.0), La (5.2), K (2.3), and Co (2.0) showed higher ratio, which suggests that the ETS is one of the possible increasing factors of PM2.5 and elemental concentration at indoor environment.

Chemical properties of insoluble precipitation residue particles

Precipitation chemistry can provide unique insights into the composition of aerosol particles involved in precipitation processes. Until recently, precipitation chemistry studies focused predominantly on soluble components. Analyzing the single particle insoluble components in addition to soluble ions in precipitation can provide detailed information on the individual particles originally in the cloud or removed by precipitation as well as the source of the aerosols. Herein, we present an in-depth analysis of resuspended residues from precipitation samples collected at a remote site in the Sierra Nevada Mountains in California during the 2009–2011 winter seasons. In addition, we present results from laboratory control experiments of dust, leaf litter, smoke, and sea salt samples that were conducted to better understand how insoluble and soluble residues are distributed during the atomization process and aid in the classification of the residue compositions in the precipitation samples. Further, immersion freezing ice nuclei (IN) measurements of insoluble residues from precipitation water enabled the determination of residue types that likely seeded clouds. Long-range transported dust mixed with biological material tended to be more IN active, while purely biological residues contained a variety of high and low temperature IN. Overall, results from this study can be used as a benchmark for classification of insoluble precipitation residues in future studies. Knowledge of the precipitation chemistry of insoluble residues coupled with meteorological and cloud microphysical measurements will ultimately improve our understanding of the link between aerosols, clouds, and precipitation.

Atmospheric PM and volatile organic compounds released from Mediterranean shrubland wildfires

Wildfires produce a significant release of gases and particles affecting climate and air quality. In the Mediterranean region, shrublands significantly contribute to burned areas and may show specific emission profiles. Our objective was to depict and quantify the primary-derived aerosols and precursors of secondary particulate species released during shrubland experimental fires, in which fire-line intensity values were equivalent to those of moderate shrubland wildfires, by using a number of different methodologies for the characterization of organic and inorganic compounds in both gas-phase and particulate-phase. Emissions of PM mass, particle number concentrations and organic and inorganic PMx components during flaming and smouldering phases were characterized in a field shrubland fire experiment. Our results revealed a clear prevalence of K+ and SO42− as inorganic ions released during the flaming–smouldering processes, accounting for 68–80% of the inorganic soluble fraction. During the residual-smouldering phases, in addition to K+ and SO42−, Ca2+ was found in significant amounts probably due the predominance of re-suspension processes (ashes and soil dust) over other emission sources during this stage. Concerning organic markers, the chromatograms were dominated by phenols, n-alkanals and n-alkanones, as well as by alcohol biomarkers in all the PMx fractions investigated. Levoglucosan was the most abundant degradation compound with maximum emission factors between 182 and 261 mg kg−1 in PM2.5 and PM10 respectively. However, levoglucosan was also observed in significant amounts in the gas-phase. The most representative organic volatile constituents in the smoke samples were alcohols, carbonyls, acids, monocyclic and bicyclic arenes, isoprenoids and alkanes compounds. The emission factors obtained in this study may contribute to the validation and improvement of national and international emission inventories of this intricate and diffuse emission source.

Exposure to Atmospheric Particulate Matter Enhances Th17 Polarization through the Aryl Hydrocarbon Receptor

Lung diseases, including asthma, COPD, and other autoimmune lung pathologies are aggravated by exposure to particulate matter (PM) found in air pollution. IL-17 has been shown to exacerbate airway disease in animal models. As PM is known to contain aryl hydrocarbon receptor (AHR) ligands and the AHR has recently been shown to play a role in differentiation of Th17 T cells, the aim of this study was to determine whether exposure to PM could impact Th17 polarization in an AHR-dependent manner. This study used both cell culture techniques and in vivo exposure in mice to examine the response of T cells to PM. Initially experiments were conducted with urban dust particles from a standard reference material, and ultimately repeated with freshly collected samples of diesel exhaust and cigarette smoke. The readout for the assays was increased T cell differentiation as indicated by increased generation of IL-17A in culture, and increased populations of IL-17 producing cells by intracellular flow cytometry. The data illustrate that Th17 polarization was significantly enhanced by addition of urban dust in a dose dependent fashion in cultures of wild-type but not AHR-/- mice. The data further suggest that polycyclic aromatic hydrocarbons played a primary role in this enhancement. There was both an increase of Th17 cell differentiation, and also an increase in the amount of IL-17 secreted by the cells. In summary, this paper identifies a novel mechanism whereby PM can directly act on the AHR in T cells, leading to enhanced Th17 differentiation. Further understanding of the molecular mechanisms responsible for pathologic Th17 differentiation and autoimmunity seen after exposure to pollution will allow direct targeting of proteins involved in AHR activation and function for treatment of PM exposures.

Comparative Safety Analysis of Surgical Smoke From Transurethral Resection of the Bladder Tumors and Transurethral Resection of the Prostate

To analyze the gas generated from the transurethral resection of the prostate (TURP) and transurethral resection of bladder (TURB) tumor. Thirty-six smoke samples were collected from a continuous irrigation suction system during the TURP and the TURB. Then, they were subdivided into 2 groups: the group I (n = 18; gases generated from the TURP) and the group II (n = 18; gases generated from the TURB). We performed qualitative and quantitative analysis of the samples on gas chromatography/mass spectrometry. A more diverse type of gas was generated from the TURB as compared with the TURP. A further quantitative analysis was performed for 7 of 16 gases and 13 of 39 gases in the group I and group II, respectively. This showed that there was no significant difference in the concentration of propylene (propylene: 148.36 ± 207.72 ug/g vs 96.956 ± 135.138 ug/g) and 1-pentene (5137.08 ± 2935.48 ug/g vs 4478.259 ± 5787.351 ug/g) between the TURP and the TURB (P >.05). Our results showed that 39 and 16 types of gases were generated from the TURB and the TURP, respectively. There were differences in the types of gases between benign hypertrophic prostate and malignant bladder tumor tissues. This indicates that electrosurgery of malignant tissue is possibly more hazardous to those who are involved in the surgical operation.

Heart-cutting two-dimensional gas chromatography in combination with isotope ratio mass spectrometry for the characterization of the wax fraction in plant material

Gas chromatography coupled to isotope ratio mass spectrometry after on-line combustion (GC–C-IRMS) and high temperature conversion (GC–HTC-IRMS) is used for compound specific isotope ratio determination. This determination can only be performed successfully if the target solutes are fully resolved from other compounds. A new instrumental set-up consisting of heart-cutting two-dimensional GC based on capillary flow technology and a low thermal mass GC oven in combination with an isotope ratio mass spectrometer is presented. Capillary flow technology was also used in all column and interface connections for robust and leak-free operation. The new configuration was applied to the characterization of wax compounds in tobacco leaf and corresponding smoke samples. It is demonstrated that high accuracy is obtained, both in the determination of δ13C and δ2H values, allowing the study of biosynthesis and delivery mechanisms of naturally occurring compounds in tobacco.

Emission factors and detailed chemical composition of smoke particles from the 2010 wildfire season

This paper complements the information previously published (Atmospheric Environment 45, 641–649) on gaseous and particulate emissions from wildfires in Portugal for summer 2009, in an attempt at obtaining more extensive, complete and representative databases on emission factors and detailed chemical characterisation of smoke particles. Here, emission factors for carbon oxides (CO2 and CO), total hydrocarbons (THC), fine (PM2.5) and coarse (PM2.5–10) particles obtained for fires occurring in Portugal in summer 2010 are presented. The carbonaceous content (OC and EC), water-soluble ions, elements and organic composition of smoke particles were, respectively, analysed by a thermal-optical transmission technique, ion chromatography, instrumental neutron activation analysis (INAA) and gas chromatography-mass spectrometry (GC–MS). The particle mass concentrations were in the ranges 0.69–25 mg m−3 for PM2.5 and 0.048–3.1 mg m−3 for PM2.5–10. PM2.5 particles represented 91 ± 5.7% of the PM10 mass. The OC/EC ratios in fine and coarse particles ranged from 2.5 to 205 and from 1.7 to 328, respectively. The water-soluble ions represented, on average, 3.9% and 2.8% of PM2.5 and PM2.5–10 mass, respectively. In general, the dominant ions in the water extracts were Na+, NH4+, Cl− and NO3− for the PM2.5 fraction, and K+, Mg2+, Ca2+ and SO42− for the PM2.5–10 fraction. The K+/EC and K+/OC ratios obtained in this study were, on average, 0.22 ± 0.23 and 0.011 ± 0.014 for PM2.5 and 0.83 ± 1.0 and 0.024 ± 0.023 for PM2.5–10 particles, respectively. The K+/levoglucosan ratio was, on average, 2.0 for PM2.5 and 3.1 for PM2.5−10 particles. Levoglucosan was detected at mass fractions of 1.6–8.7 mg g−1 OC in PM2.5 and 2.7–56 mg g−1 OC in PM2.5–10. The dominant elements detected in the smoke samples were Na, Br, Cr, Fe, K, Rb and Zn. The most representative organic constituents in the smoke samples were acids, alcohols, terpenoid-type compounds, sugars and phenols, in both size fractions.

Emission of Polycyclic Aromatic Hydrocarbons from Beech Wood Combustion

This study reports results on 16 EU priority polycyclic aromatic hydrocarbons in smoke produced by beech wood combustion from Zlatibor region, Serbia. Smoke samples were collected with two different types of tubes (PUF and XAD-2), at a height of 2 and 5 m away from the firebox; 16 EU priority polycyclic aromatic hydrocarbons [European Commission (2005), Commission Recommendation 2005/108/EC, Official Journal of European Union L34:43–45; JECFA (2005), Summary and Conclusion. Paper No. JECFA/64/SC, Joint FAO/WHO Expert Committee on Food Additives, Sixty-Fourth Meeting, Rome, Italy, February 8–17] were identified and quantified by Fast-GC/HRMS. The analyzed PAHs were: benzo[c]fluorene (BcL), benzo[a]anthracene (BaA), cyclopenta[c,d]pyrene (CPP), chrysene (CHR), 5-methylchrysene (5MC), benzo[b]fluoranthene (BbF), benzo[j]fluoranthene (BjF), benzo[k]fluoranthene (BkF), benzo[a]pyrene (BaP), benzo[g,h,i]perylene (BgP), dibenzo[a,h]anthracene (DhA), indeno[1,2,3-cd]pyrene (IcP), dibenzo[a,e]pyrene (DeP), dibenzo[a,h]pyrene (DhP), dibenzo[a,i]pyrene (DiP) and dibenzo[a,l]pyrene (DlP). Results show that total emission of polycyclic aromatic hydrocarbons at a height of 2 m was 6.7 and 7.4 mg m−3 , in PUF and XAD-2 tubes, respectively. At height of 5 m polycyclic aromatic hydrocarbons emission was 2.4 and 4.3 mg m−3 , in PUF and XAD-2 tubes, respectively. BaP contribution to total sum of 16 EU priority polycyclic aromatic hydrocarbons was 4% (PUF tubes) and 7.2% (XAD-2 tubes) at a height of 2 m, and 5% (PUF tubes) and 8.3% (XAD-2 tubes) at a height of 5 m. Total benzo[a]pirene equivalent concentrations (BaPeq) in smoke samples were calculated.

Investigation of Arsenic Airborne in Particulate Matter around Caterers’ Wood Fires in the Cape Town Region

Smoke from wood fires has long been recognized as a significant health hazard. Our recent work has reported on the occurrence of waste timber previously treated by chromated copper arsenate (CCA) insecticide in the fuel supplies of informally operating caterers in the Cape Town region. The main objective of this paper is to report evidence that the burning of CCA-treated wood by informal caterers does lead to arsenic enrichment of the smoke. Atmospheric particulate matter with aerodynamic diameter ≤ 10 μm (PM10) was collected using an Air Metrics MiniVol portable aerosol sampler onto quartz filters for durations varying from 1 h to 4 h, at 5 L/min. Smoke was first sampled under controlled conditions, in which CCA-treated samples (of hazard classes H5 and H2) and two untreated wood samples were burned. 18 field samples were collected, from Nyanga, Langa and Khayelitsha (Cape Town) and Kayamandi (Stellenbosch). The PM10 concentrations were calculated and the smoke samples were microwave-digested using nitric acid for metals analysis by ICP-AES. Under controlled conditions, the concentrations of arsenic volatilised from (H2 and H5) were 19 and 52 μg/m 3 , and the As:Cu and As:Cr ratios strongly increased compared the ratios found in the timber. The lowest concentration of PM10 was found around the Nyanga taxi rank at a distance of ± 100 m from caterers, at 33 μg/m 3 , while the highest concentration was 8139 μg/m 3 for a 1-hour sample representing occupational exposure close to wood burning fires. Arsenic was detected in 15 smoke samples. The average arsenic level of positive samples was 1.3 μg/m 3 . The arsenic levels measured exceed normal background levels, which have been reported by the WHO to be 0.02–4 ng/m 3 in rural air and up to 30 ng/m 3 in urban air.

Comparison of the effects of e-cigarette vapor and cigarette smoke on indoor air quality

Context: Electronic cigarettes (e-cigarettes) have earned considerable attention recently as an alternative to smoking tobacco, but uncertainties about their impact on health and indoor air quality have resulted in proposals for bans on indoor e-cigarette use.Objective: To assess potential health impacts relating to the use of e-cigarettes, a series of studies were conducted using e-cigarettes and standard tobacco cigarettes.Methods and materials: Four different high nicotine e-liquids were vaporized in two sets of experiments by generic 2-piece e-cigarettes to collect emissions and assess indoor air concentrations of common tobacco smoke by products. Tobacco cigarette smoke tests were conducted for comparison.Results: Comparisons of pollutant concentrations were made between e-cigarette vapor and tobacco smoke samples. Pollutants included VOCs, carbonyls, PAHs, nicotine, TSNAs, and glycols. From these results, risk analyses were conducted based on dilution into a 40 m3 room and standard toxicological data. Non-cancer risk analysis revealed “No Significant Risk” of harm to human health for vapor samples from e-liquids (A-D). In contrast, for tobacco smoke most findings markedly exceeded risk limits indicating a condition of “Significant Risk” of harm to human health. With regard to cancer risk analysis, no vapor sample from e-liquids A-D exceeded the risk limit for either children or adults. The tobacco smoke sample approached the risk limits for adult exposure.Conclusions: For all byproducts measured, electronic cigarettes produce very small exposures relative to tobacco cigarettes. The study indicates no apparent risk to human health from e-cigarette emissions based on the compounds analyzed.