Gas Chromatography-mass Selective Detection Research Articles

Characterization of polycyclic aromatic hydrocarbons in mangrove sediments from Ifiekporo Creek, Warri, Nigeria

The occurrence and level of polycyclic aromatic hydrocarbons (PAHs) in mangrove sediment from Ifiekporo Creek in Warri, Delta State, Nigeria, were assessed in this study. The extraction of PAHs from the sediment samples was achieved using the PAH analytical test method (USEPA 8270). This method measures the individual concentrations of extractable PAHs in samples. The PAHs were quantified within the C11-C22 subgroup. The basic GC parameters for the analysis of polyaromatic hydrocarbons were analysed using a gas chromatography‒mass selective detector (GC‒MSD). The individual PAH concentrations in the mangrove sediment samples ranged from 850 µg/kg−1 to 3470 µg/kg−1. PAH source apportionment employing isomeric ratios and multivariate statistics indicated both pyrogenic and petrogenic source inputs in the sediment samples. The order of PAH homology in the sediment was 3-ring > 2-ring > 4-ring. The sediment samples were mostly dominated by LMW PAHs. The results of the ecological risk assessment in the study area indicate that there is low ecological risk associated with PAH exposure in sediment. These results provide data on the concentrations and compositional patterns of PAHs, which is useful for understanding the effects, sources, fates, and transport of PAHs in sediment in the study area, as well as for providing relevant information for environmental quality management and forensic studies.

Profile change of the volatile and non-volatile compounds in dried or baked laver by photooxidation.

Effects of light or dark storage condition on the profile changes of volatile and non-volatile compounds were evaluated in dried and baked laver for 60 days. Volatile and non-volatile compounds were analyzed using gas chromatography-mass selective detection and high-performance liquid chromatography-quadrupole-time of flight-mass spectrometry, respectively. Baked laver stored in light conditions for 60 days produced the most volatile compounds, whereas dried laver stored in the dark produced the least volatile compounds. Total 11 classes of volatile compounds were detected, including alkanes, alkenes, and ketones, with aldehydes being most abundant in dried laver stored under light. Metabolite analysis of non-volatile compounds led to the selection of 12 compounds with a higher variable importance projection (VIP) value of >1.0: 6 fatty acids (VIP 1.2-2.0), 2 flavanols (VIP 1.3-1.8), hydroxybenzoic acid (VIP 1.5), hydroxycinnamic acid (VIP 2.3), a phenolic acid ester (VIP 1.9), and phloroglucinol (VIP 1.2). Generally, levels of these compounds decreased more following storage in the light than under dark, irrespective of laver preparation. The content of linolenic acid was particularly affected by storage conditions, with light conditions causing a fourfold reduction in linolenic acid level compared with dark conditions, which could result in an increased formation of aldehydes. Gallic acid and sinapinic acid were detected in dried but not baked laver, as they are destroyed by heat treatment. Therefore, laver should be baked and stored in dark conditions to prevent the development of rancidity. PRACTICAL APPLICATION: Laver is one of the representative seaweeds, and the popularity among consumers increases. Although commercially available laver is prepared in dried or baked condition, scientific studies on the changes of metabolites, including volatile and non-volatile compounds during storage, are scarce. The results of this study can be applied to improve proper storage methods to maintain the quality of laver, which can be beneficial for consumers and food industry.

Spatial modeling of ambient concentrations of volatile organic compounds in Montreal, Canada.

Background:Volatile organic compounds (VOCs) are components of the complex mixture of air pollutants within cities and can cause various adverse health effects. Therefore, it is necessary to understand their spatial distribution for exposure assessment in epidemiological studies.Objectives:The objective was to model measured concentrations of five VOCs within the city of Montreal, Canada, developing spatial prediction models that can be used in health studies.Methods:We measured concentrations using 3M 3500 Organic Vapor Monitors, over 2-week periods, for three monitoring campaigns between 2005 and 2006 in over 130 locations in the city. Using GC/MSD (Gas Chromatography/Mass Selective Detector), we measured concentrations of benzene, n-decane, ethylbenzene, hexane, and trimethylbenzene. We fitted four different models that combine land-use regression and geostatistical methods to account for the potential spatial structure that remains after accounting for the land-use variables. The fitted models also accounted for possible variations in the concentration of air pollutants across campaigns.Results:The highest concentrations for all VOCs were found in December with hexane being the most abundant followed by ethylbenzene. We obtained predicted surfaces for the VOCs for the three campaigns and mean surfaces across campaigns. We found higher concentrations of some VOCs along highways and in the Eastern part of Montreal, which is a highly industrialized area.Conclusions:Each of the fitted models captured the spatial and across-campaigns variability for each VOC, and we found that different VOCs required different model structures.

Metabolite analysis and anti-obesity effects of celery seed in 3T3-L1 adipocytes.

Celery seeds were fractioned successively by organic solvents, and fractions were screened for their antioxidant properties. Metabolites of high antioxidative fractions were analyzed, and then anti-obesity properties and mechanisms of selected fractions were evaluated in 3T3-L1 adipocytes. Celery seed ethanol extract (CSE) and celery seed ethyl acetate fraction (CSEA) possessed higher in vitro antioxidant properties, including radical scavenging and total phenolic content, than that of hexane, butanol, and water fractions. Total of 43 and 19 metabolites were identified from CSE and CSEA, respectively, by gas chromatography-mass selective detector. Isoferulic acid and p-coumaric acid were only found in CSEA. CSEA possessed higher anti-adipogenesis in the 3T3-L1 cells than CSE by decreasing adipogenic hormones, including leptin and adiponectin. Expression levels of adipocyte-related transcription factors and genes such as C/EBPα, PPARγ, aP2, and FAS decreased to comparable levels of control. CSEA could be used as a natural ingredient with antioxidant and anti-obesity functionality.

In-situ penetration of ionic liquids during surface densification of Scots pine

Abstract The moisture-induced recovery of compressed wood is one of the major problems of wood densification technology. Achieving a cost-efficient surface densification process without the need for additional resins to eliminate the set-recovery may lead to an increase in value of low-density wood species. A previous study has shown that a pre-treatment with ionic liquids (ILs) can nearly eliminate the set-recovery. It was however observed that during the pre-treatment process the IL did not penetrate sufficiently deep into the wood to explain the achieved reduction in set-recovery. Based on these findings, the hypothesis was posed that further penetration of the IL into the wood occurs during the densification stage as a consequence of the applied heat and pressure. Thermo-gravimetric analysis (TGA) and gas-chromatography mass-selective-detection (GC-MSD) showed that the depth of penetration of the IL was greater after the densification process than before. Digital image correlation (DIC) showed that in regions with a high IL concentration, there was almost no set-recovery, and it gradually increased with a decrease in the IL concentration, as observed with TGA and GC-MSD analysis.

P5625Markers for cholesterol absorption are associated with In-stent-restenosis after coronary stenting in stable coronary artery disease: An Optical Coherence Tomography study

Abstract Background Plant sterols are suspected to exert atherosclerotic propensity. Modern drug-eluting stents are superior to bare metal stents but show a late catch up phenomenon for restenosis. Due to its superb resolution, optical coherence tomography (OCT) has the capability to identify and quantifiy very early patterns of in-stent proliferation. Studies have shown that in-stent neointimal proliferation is linked to late in-stent stenosis. Purpose This study aimed to analyze associations of plasma levels for markers of cholesterol homeostasis such as campesterol and sitosterol (markers for cholesterol absorption) as well as lanosterol (marker for cholesterol synthesis)and and their respective oxides with In-stent restenosis after stent deployment in stable coronary artery disease. Methods Plasma cholesterol was measured by gas chromatography-flame ionization detection. Plasma campesterol, sitosterol and lanosterol and their oxides were analyzed by gas chromatography-mass selective detection. In-stent proliferation (restenosis) was assessed after six months by OCT in 33 patients (21 males). A quantitative OCT algorithm was applied to each stent by steps of one mm and in-stent proliferation volumes and areas were calculated and normalized to stent length and area. In-stent proliferation can be measured by OCT as global volumes and focal areas. Results No clinically significant restenosis or angiographic restenosis of >30% was observed at 6-month f/u. Mean cholesterol level was 166,5±62,8 mg/dl and positively correlated with proliferation volume/cm (r=0.316, p=0.037) and absolute median proliferation area (r=0.322, p=0.029). Absolute median proliferation area and relative median proliferation area correlated positively with markers for cholesterol absorption such as campesterol-to-cholesterol (r=0.277, p=0.07 and 0.315, p=0.037) and sitosterol-to-cholesterol (r=0.237, p=0.092 and 0.322, p=0.034), whereas lanosterol (a marker for cholesterol synthesis) and its ratio to cholesterol correlated negatively with proliferation volumes and areas (p<0.05; table). Moreover, 7-beta-OH-campesterol correlated positively with proliferation volumes and areas (p<0.05, table). Also, the ratio of 7-beta-OH-campesterol-to-cholesterol correlated positively with proliferation volumes and areas (p<0.1,; table), but did not reach significance in this relatively small sample size. Morevover, there was a positive association of the sum of all plant sterol oxides with In-stent restenosis (data not shown). Conclusions In this hypothesis-generating study, in-stent proliferation assessed by OCT at six months follow-up was positively associated with markers for cholesterol absorption and negatively associated with markers for cholesterol synthesis. Larger studies will have to evaluate whether patients with high cholesterol absorption might benefit in particular from combined-lipid-lowering therapy with a statin and a cholesterol absorption Inhibitor.

VOLATOLOMICS COMBINED TERAHERTZ TIME - DOMAIN SPECTRAL ANALYSES OF COLON CANCER IN VITRO

Terahertz time-domain spectroscopy (THz-TDS) offers a great advantage for the analysis of biological samples. In this study, we combined THz-TDS with volatolomics analysis and analyzed 2 colon cell lines via in vitro settings. The release of volatile organic compounds (VOCs) was measured from the normal colon (CCD112CoN) and cancer colon (COLO320DM) cell lines which were grown in sealed flasks. Data validation were carried out with principal component analysis (PCA) and partial least square (PLS) scores while the chemometric analyses were performed using Camo Unscrambler X software. In-depth THz-TDS spectral analysis of the cancer colon (COLO320DM) cell line shows significant traces of benzamide gas when validated using gas chromatography-mass selective detection (GC-MSD) system. This preliminary data shows the potential use of identification and quantification of benzamide compound in the cancer colon cells and this could provide useful insight towards cancer drug design and therapy.

Experimental Study of Destructive Distillation of Maiganga Coal: Analysis of Products’ Yield and Composition

The research involves destructive distillation of Maiganga coal, analysis of the yields and characterization of condensable products. Maiganga coal was distillated in a pyrolyser, the condensable products were recovered in a three stage separator, and the products were collected over a range of temperatures. The yields’ of the char was obtained by measuring the weight of the char and then divided by the starting weight of the coal sample. The condensable products yields were obtained in similar manner as the char. The yield of the gaseous product was obtained by subtracting the sum of yields of char and condensable products from unity. The yields of semi-coke, water and tar were 63, 11, and 7%, respectively. The tar obtained was characterize using GC/MS to determine the chemical composition. The characterization was carried out using Agilent Gas Chromatography/ Mass Selective Detector (GC/MSD). The GC/MSD results show that the dominant compounds in the tar are aromatic, acid, and esters. However sulphur, nitrogen, chlorine, and fluorine compounds were present. The specific dominant compound is Benzeneacetic acid, 4-tetradecyl ester, (C₂₂H₃₆O₂) about 33%, and the least were 1H-Thiopine, 2,3,6,7-tetrahydro-4,5-didehydro-3,3,6,6-tetramethyl (C₁₀H₁₆OS), 1-oxide, 4-(2,5-Dihydro-3-methoxyphenyl)butylamine (C₁₁H₁₉NO) about 6%. The coal may serve as feedstock for production of coke and aromatic compounds.

Plasma levels of the oxyphytosterol 7α-hydroxycampesterol are associated with cardiovascular events

Background and aimsThere are safety issues regarding plant sterol ester-enriched functional food. Oxidized plant sterols, also called oxyphytosterols, are supposed to contribute to plant sterol atherogenicity. This study aimed to analyze associations of plasma oxyphytosterol levels with cardiovascular events. MethodsPlasma cholesterol was measured by gas chromatography-flame ionization detection. Plasma campesterol and sitosterol and their 7-oxygenated metabolites were analyzed by gas chromatography-mass selective detection. ResultsIn 376 patients admitted for elective coronary angiography, who were not on lipid-lowering drugs, 82 cardiovascular events occurred during a follow-up period of 4.2 ± 1.8 years. Patients with cardiovascular events had significantly higher 7α-hydroxycampesterol plasma levels (median, 0.46; [interquartile range (IQR) 0.22–0.81] nmol/L vs. median, 0.25 [IQR, 0.17–0.61] nmol/L; p = 0.003) and 7α-hydroxycampesterol-to-cholesterol ratios (median 0.08 [IQR, 0.04–0.14] nmol/mmol vs. median, 0.05 [IQR 0.03–0.11] nmol/mmol; p = 0.005) than controls without such events. Patients above the median were characterized by higher cumulative event rates in Kaplan-Meier-analysis (Logrank-test p = 0.084 and p = 0.025) for absolute and cholesterol corrected 7α-hydroxycampesterol, respectively. After adjustment for influencing factors and related lipids, the hazard ratios per one standard deviation of the log-transformed variables (HR) were 1.19 [95% confidence interval (CI), 0.95–1.48], p = 0.132 for 7α-hydroxycampesterol and HR, 1.18 [95% CI, 0.94–1.48], p = 0.154 for 7α-hydroxycampesterol-to-cholesterol ratio. None of the other investigated oxyphytosterols showed an association with cardiovascular events. ConclusionsIn patients not on lipid-lowering drugs, absolute plasma levels of 7α-hydroxycampesterol and their ratios to cholesterol are associated with cardiovascular events. Further research is required to elucidate the role of OPS in cardiovascular diseases.

Bioremediation of hexachlorocyclohexane (HCH) in soil using spent mushroom compost of Pleurotus ostreatus

Hexachlorocyclohexane (HCH), a highly chlorinated pesticide, was used worldwide in the 1950s and 1960s. HCH toxic residues are still detected in environmental compartments. Thus, effective, viable and eco-friendly strategy is required for its remediation. In this study, degradation of four HCH isomers was evaluated by amending contaminated soil using four treatments of spent mushroom compost (SMC) of Pleurotus ostraetus. The soil was incubated for 5 weeks and was sampled every seven days. Quantitative attenuation in HCH was calculated using gas chromatography–electron capture detector (GC-ECD) and metabolite was identified using gas chromatography–mass selective detector (GC-MSD). Maximum reduction 58%, 26%, 45%, and 64% for α-, β-, γ- and δ-HCH isomers, respectively, using SMC and soil (both unsterilized) showed that this treatment was the best for bioremediation of HCH in soil. However, when one of the factors, either soil or SMC, was sterilized, a significant reduction in HCH degradation was noticed. The second most reduction of isomers was seen during treatment where unsterilized SMC was added in sterilized soil followed by treatment where SMC was sterilized but soil was not. Abiotic control did not remove any significant quantities of HCH. Simple first-order (SFO) kinetic confirmed that SMC reduced the half-live manifolds as compared to biotic control. Only one metabolite δ-PCCH was identified during the course of study.

ENVIRONMENTAL IMPACT OF VOLATILE ORGANIC COMPOUNDS EMITTED FROM ASPHALT PAVEMENT

Hot mix asphalt (HMA) is a major construction material used for building roads, airport runways, and parking lots (ASCE 2014). During HMA construction, a massive amount of volatile organic compounds (VOC'Ss) is emitted from the hot asphalt mixtures, creating a potential health risk to on-site workers. Few studies have quantitatively investigated (Chong et al., 2013). The constituents and the potential health effects of the VOC's generated from HMA pavement construction were studied. This paper presents the results of a study in which air samples were collected at multiple locations and time points of several projects during HMA pavement construction and were their chemical compositions and concentrations subsequently characterized by using gas chromatography/mass selective detector (GC/MSD). Although the individual concentrations of the identified chemicals were found to be below various exposure limits, their collective effect on human health remains unknown and may not be ignored (Chong et al., 2013).

FATTY ACIDS COMPOSITION IN MACADAMIA SEDES OIL (MACADAMIA INTEGRIFOLIA) FROM ECUADOR

Objective: The aim of this study was to determine the fatty acids composition in a macadamia seeds oil sample cultivated in Ecuador.Materials & Methods: macadamia oil was obtained of macadamia seeds using the cold pressing method. Fatty acids analysis was carried out using the Gas Chromathography method with a Mass Selective Detector (GC/MSD) and using the data base Library NIST14.L to identify the compounds.Results: macadamia seeds have a high content of unsaturated fatty acids with 41.36% of oleic acid. Macadamia seeds oil has 37.77% of polyunsaturated fatty acids of which 3.79% ɷ6 α- Linoleic and 33.98% of ɷ3 α- Linolenic. Macadamia seeds only have 9.33% of palmitic acid. Conclusions: Macadamia seeds are a good source of monounsaturated fatty acids oleic acid and with a good content of ɷ6 α- Linoleic and ɷ3 α- Linolenic. This profile enables their use as a good and healthy oil to be used in the food industry in Ecuador. Keywords: Macadamia, Macadamia integrifolia, Fatty acids, Gas chromatography-mass selective detector, Methyl ester, Omega acids.

버스 정비 작업자에 대한 석면 및 디젤 엔진 배출물질 노출 평가

Objectives: Lung cancer occurred with worker working in an urban bus garage. A survey was conducted to investigate whether lung cancer had causal relationship with work. Exposure to asbestos and diesel engine exhaust were suspected. Methods: Airborne asbestos was sampled on membrane filter and analyzed using phase-contrast microscopy. Airborne diesel exhaust was sampled using quartz filter and analyzed with thermal-optical analyzer. Polynuclear aromatic hydrocarbons was sampled using PTFE filter and XAD-2 tube and analyzed with gas chromatography-mass selective detector. Results: Airborne asbestos concentration was under 0.01 fiber/cc. Worker who warmed up an engine of urban bus for 2 hours was exposed to elemental carbon concentration, <TEX>$15.5{\mu}g/m^3$</TEX>. Only naphtalene among polynuclear aromatic hydrocarbons was detected. Conclusions: It was difficult to conclude about worker exposure to asbestos because working hour related asbestos was too short. In reviewing papers, the exposure to asbestos over 0.01 fiber/cc during exchange brake lining was found. It was identified that worker's occupational exposure to diesel exhaust based on elemental carbon was higher than the other occupational exposure to diesel exhaust.

Micro-solid phase extraction followed by thermal extraction coupled with gas chromatography-mass selective detector for the determination of polybrominated diphenyl ethers in water

A method of analyzing environmental contaminants in water based on micro-solid phase extraction (μ-SPE) followed by thermal extraction (TE) and a cold-trapping step, coupled with gas chromatography-mass selective detection (GC–MSD) was developed and validated. μ-SPE–TE– GC–MSD was employed in the determination of five polybrominated diphenyl ethers. The μ-SPE sorbent was chitosan-graphene oxide (CS-GO) composite, which was prepared by mixing CS and GO by means of ultrasonication. The CS in the composite was cross-linked with glutaraldehyde. After μ-SPE, the analytes in the extract were extracted thermally in a thermal desorption unit tube combined with a cooled injection system, coupled to GC–MSD. The extraction conditions were optimized for the detection of the target compounds in water. This method provided linearity ranges of between 0.1 and 20μgL−1 (depending on the analytes), with coefficients of determination, r2, ≥0.9982. The calculated relative recoveries were between 71.52 and 96.15% whereas precision (based on % relative standard deviations) was between 3.54 and 11.36%. The method showed limit of detection and limit of quantification ranges of between 0.007 and 0.016μgL−1, and between 0.023 and 0.054μgL−1, for the two groups of analytes, respectively. The method was applied to the determination of the target analytes in water.

Experimental Investigation on Hydrogen Production by Anthracene Gasification in Supercritical Water

Char conversion is the rate-determining step for coal gasification in supercritical water, because the main components of char are polycyclic aromatic hydrocarbons (PAHs) with chemical stability. Anthracene was selected as the model PAH compound to explore the gasification mechanism of coal in supercritical water. The experimental parameters investigated with autoclaves were within the following ranges: temperature, 600–750 °C; residence time, 5–30 min; and pressure, 23–25 MPa. The main gas products were H2 and CO2. The liquid intermediates were analyzed by gas chromatography–mass-selective detection (GC-MSD) for qualitative analysis and quantitative analysis, respectively. Benzene and naphthalene were found to be relatively stable compounds in the liquid products. Effective catalyst and appropriate temperature were obtained to enhance the gasification process.

Characteristics and reactivity of volatile organic compounds from non-coal emission sources in China

Volatile organic compounds (VOCs) were sampled from non-coal emission sources including fuel refueling, solvent use, industrial and commercial activities in China, and 62 target species were determined by gas chromatography-mass selective detector (GC-MSD). Based on the results, source profiles were developed and discussed from the aspects of composition characteristics, potential tracers, BTEX (benzene, toluene, ethylbenzene and xylene) diagnostic ratios and chemical reactivity. Compared with vehicle exhausts and liquid fuels, the major components in refueling emissions of liquefied petroleum gas (LPG), gasoline and diesel were alkenes and alkanes. Oppositely, aromatics were the most abundant group in emissions from auto-painting, book binding and plastic producing. Three groups contributed nearly equally in printing and commercial cooking emissions. Acetone in medical producing, chloroform and tetrachloroethylene in wet- and dry-cleaning, as well as TEX in plastic producing etc. were good tracers for the respective sources. BTEX ratios showed that some but not all VOCs sources could be distinguished by B/T, B/E and B/X ratios, while T/E, T/X and E/X ratios were not suitable as diagnostic indicators of different sources. The following reactivity analysis indicated that emissions from gasoline refueling, commercial cooking, auto painting and plastic producing had high atmospheric reactivity, and should be controlled emphatically to prevent ozone pollution, especially when there were large amounts of emissions for them.

In vivo absorption and disposition of α-cedrene, a sesquiterpene constituent of cedarwood oil, in female and male rats

This study aimed to evaluate the potential of α-cedrene as a new anti-obesity drug by characterizing absorption, metabolism and pharmacokinetics in rats. α-Cedrene was administered intravenously (10 and 20 mg/kg) and orally (50 and 100 mg/kg) to female and male Sprague–Dawley rats. Blood, tissues, urine, and feces were collected at predetermined times. α-Cedrene concentrations were determined by a validated gas chromatography–tandem mass spectrometry (GC–MS/MS). A gas chromatography–mass selective detection (GC–MSD) method was used to identify the major metabolite. After i.v. injection, α-cedrene exhibited a rapid clearance (98.4–120.3 ml/min/kg), a large distribution volume (35.9–56.5 l/kg), and a relatively long half-life (4.0–6.4 h). Upon oral administration, it was slowly absorbed (Tmax = 4.4 h) with bioavailability of 48.7–84.8%. No gender differences were found in its pharmacokinetics. Upon oral administration, α-cedrene was highly distributed to tissues, with the tissue-to-plasma partition coefficients (Kp) far greater than unity for all tissues. In particular, its distribution to lipid was notably high (Kp = 132.0) compared to other tissues. A mono-hydroxylated metabolite was identified as a preliminary metabolite in rat plasma. These results suggest that α-cedrene has the favorable pharmacokinetic characteristics to be further tested as an anti-obesity drug in clinical studies.

Volatile Flavor Compounds in the Leaves of Fifteen Taxa of Korean Native Chrysanthemum Species

This study was conducted to compare the volatile flavor compounds found in the leaves of 15 taxa of Korean native Chrysanthemum species. The volatile flavor compounds from the taxa were collected using a simultaneous steam distillation and extraction technique and were analyzed using gas chromatography/mass selective detector (GC/MSD). A total of 45 volatile flavor compounds were identified with six functional groups: 14 alcohols, 4 ketones, 19 hydrocarbons, 5 esters, 2 acids, and 1 aldehyde. The main functional group in 15 taxa of Chrysanthemum species was alcohols, accounting for 28.7% of volatile flavor compounds, followed by ketones (21.2%) and hydrocarbons (13.2%). Camphor, which is known for its antimicrobial properties, was the most abundant volatile compound (30%) in C. zawadskii ssp. latilobum and var. leiophyllum. In particular, C. indicum subspecies and C. boreale contained <TEX>${\alpha}$</TEX>-thujone, which has outstanding anti-bacterial, anti-cancer, anti-inflammatory, anti-ulcer, and anti-diabetic efficacies. C. indicum var. albescens could be used in perfumes, since it showed 21 times more camphene than C. indicum. In addition, C. indicum var. acuta contained a fairly high content of 1,8-cineole, which has an inhibitory effect on mutagenesis. C. lineare contained only pentadecanoic acid compounds, whereas other taxa hexadecanoic acids. Overall, the Korean native Chrysanthemum species had considerable variation in volatile flavor compounds in their leaves. This study provides a good indication of specific potential use for various applications.

Concentration, Source, and Carcinogenic Risk of PAHs in the Soils from Jiaozhou Bay Wetland

16 surface soil samples were collected from Jiaozhou Bay wetland. The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) were measured by gas chromatography-mass selective detector (GC/MS). The total concentration of PAHs ranged from 176.1–563.3 ng/g dry weight, with a mean of 345.3 ng/g dry weight. Factor analysis was calculated to apportion sources of PAHs. It was found that the PAHs mainly from coal burning, traffic sources, diesel leakage, coke production, oil exploitation and petroleum leakage. Seven carcinogenic PAHs classified by the IARC were calculated for the health risk assessment. Two groups of people (children and adults) were selected to estimate the carcinogenic risk via ingestion, inhalation, and dermal contact. As a result, the total carcinogenic risks for children and adults were 4.8 × 10−7 and 8.8 × 10−7, respectively, and the carcinogenic risks were at acceptable range. Sensitivity analysis was conducted to evaluate the parameters which contributed most to the carcinogenic risk assessment. As as a result, the average lifespan (AT), body weight (BW), BaPeq concentrations (CS), exposure frequency (EF), and exposure duration (ED) contribute most to the carcinogenic risk assessment, and these should be acquired on a site-specific basis.

Secondhand Smoke Exposure and Urine Cotinine Concentrations by Occupation among Korean Workers: Results from the 2008 Korea National Survey for Environmental Pollutants in the Human Body

This study aimed to estimate the status of secondhand smoke (SHS) exposure through urine cotinine analysis among nonsmoking workers in Korea and to analyze factors affecting urine cotinine concentrations. Data were based on “The 2008 Korea National Survey for Environmental Pollutants in the Human Body,” a cross-sectional study of the National Institute of Environmental Research of Korea. We selected 1448 nonsmoking adult workers from 200 localities to participate in this survey. Urine cotinine concentrations were analyzed using a gas chromatograph-mass selective detector. We calculated separate covariate-adjusted geometric means for socio-demographic variables for males, females, and total subjects by analysis of covariance (ANCOVA). Statistical analyses were performed using SPSS version 18.0 (SPSS Inc., Chicago, Ill.). The prevalence of self-reported exposure to SHS was 36.9%. The geometric mean (95% confidence interval) of urine cotinine concentrations among all participants was 16.50 (14.48–18.80) μg/L. Gender, living area, education, and SHS exposure showed significant differences in urine cotinine concentrations. The urine cotinine concentrations of farmworkers and blue-collar workers such as skilled agricultural, forestry, and fishery workers, and elementary occupations were higher than those of white-collar workers such as clerical support workers, technicians, and associate professionals. Such a high proportion of the population having high urine cotinine levels indicates widespread exposure to SHS among nonsmoking workers in Korea. Furthermore, the urine cotinine levels among nonsmoking workers exposed to SHS varied by occupation. The measured urine cotinine concentration is suggested to be a valuable indication of SHS exposure in Korea.