Exposure and health risk assessment of indoor volatile organic compounds in a medical university.

Many volatile organic compounds (VOCs) are used for experiments at universities, and most of them contain benzene, toluene, ethylbenzene, xylene, and an extraction solvent of dichloromethane. This study aimed to investigate the indoor concentrations of these five compounds in different locations on campus and to evaluate possible health risks for faculty members and students in a medical university. We selected 10 locations as sampling sites to conduct 4-h monitoring sessions on weekdays each season during 2019-2020. We used a 6-liter canister to collect air samples and analyzed these five VOCs via gas chromatography with a flame ionization detector. Monte Carlo simulation was performed to evaluate the carcinogenic and noncarcinogenic risks of these five VOCs. We found that dichloromethane was the most highly detected compound (median: 621.07 µg/m3; range: 44.01-8523.91 µg/m3), and the Department of Medicine had the highest concentration of the total of these VOCs among all of the locations (median: 5595.29 µg/m3; range: 1565.67-7398.66 µg/m3). The median carcinogenic risks of dichloromethane and benzene were 6.36 × 10-5 (95% confidence interval [CI]: 6.83 × 10-6-7.37 × 10-4) and 5.47 × 10-6 (95% CI: 4.03 × 10-7-2.42 × 10-5), respectively, for faculty members, and the lower risks of 3.14 × 10-5 (95% CI: 3.39 × 10-6-3.64 × 10-4) and 2.69 × 10-6 (95% CI: 1.97 × 10-7-1.19 × 10-5) were estimated for the students. The chronic noncarcinogenic risks of four VOCs were less than one, except for dichloromethane with a median hazard index of 1.92 (95% CI: 2.11 × 10-1-2.22 × 101). This study observed the spatial variation in the concentrations of the total of five VOCs and dichloromethane. The carcinogenic risks were classified as being at the possible level, and the noncarcinogenic risk of dichloromethane was greater than the acceptable level. Increasing local exhaust ventilation during the experiment and reducing the using amount of dichloromethane are recommended actions to reduce VOCs exposures in the medical university.

Occupational exposures of flour dust and airborne chemicals at bakeries in Taiwan.

Walk-through surveys were carried out for bakeries in this study to determine the environmental characteristics of bakeries in Taiwan. Questionnaires were administrated to discover whether job-related asthma-like symptoms occurred among workers. Air sampling and analysis were also performed. The results show that the levels of inhalable flour dust ranged from 0.01-0.83 mg m-3 with an average of 0.27 mg m-3. Among the samples collected, 23% of them had concentrations higher than the ACGIH TLV-TWA (0.5 mg m-3), which indicated that inhalable flour dust was an important air pollutant for bakery workers in Taiwan. Airborne chemicals such as diacetyl, acetoin, 2,3-pentanedione, 2,3-hexanedione, 2,3-heptanedione, furfural, and acetaldehyde were also found in various levels in this study. The concentrations of acetaldehyde measured in these bakeries were 37-83 times higher than what have been reported from other studies for residential areas and Chinese restaurants. In addition, the concentrations of total VOCs in the working areas of the bakeries were over 21 times higher than the levels determined in the non-working areas. Based on our results, there appears to be a need to improve the air quality of the working environments of bakeries in Taiwan.

Vertical variation of source-apportioned PM2.5 and selected volatile organic compounds near an elevated expressway in an urban area.

Fine particulate matter (PM2.5) and volatile organic compounds (VOCs) are associated with adverse health effects and show spatial variation in three dimensions. The present study attempted to evaluate source contributions of PM2.5 and toxic VOCs in a metropolitan area focusing on the associated vertical variations. A special emphasis is put on the effects of the elevated expressway on the vertical variability of contribution estimates of the identified sources. Nine source factors, i.e., soil dust, sea salt/oil combustion, secondary nitrate, industrial emission, aged VOCs/secondary aerosol, traffic-related I, solvent use/industrial process, secondary sulfate, and traffic-related II, were identified using positive matrix factorization (PMF). The main contributors to PM2.5 were secondary sulfate (19.1%) and traffic-related emissions (traffic-related I and II, 16.1%), whereas the largest contributors to VOCs were traffic-related emissions (37.6%). The influence of the elevated expressway is suggested to be particularly critical on vertical variations of traffic-related emissions, including aging and secondary formation of locally accumulated air pollutants near roads. Increasing the building porosity under the viaduct could reduce the accumulation of air pollutants caused by the shelter effect. Additionally, in-street barriers would be beneficial in reducing population exposure to traffic-related emissions by altering the airflows near roads.

Dietary intakes of trihalomethanes and haloacetic acids from ready-to-eat vegetables in taiwan.

BACKGROUND: Chlorine-based disinfectants are often used to sanitize fruit and vegetables to produce a product called ready-to-eat (RTE) vegetables. During the disinfection process, disinfection byproducts (DBPs), such as trihalomethanes (THMs) and haloacetic acids (HAAs), might be formed via chlorination. OBJECTIVE: To determine the amounts of DBPs that occur in RTE vegetables in Taiwan, an analytical method which can detect THMs and HAAs simultaneously was developed for this study. METHODS: For HAAs, dimethyl sulfate (DMS) was first added into the sample as derivatization reagent and tetrabutylammonium hydrogen sulfate (TBA-H2SO4) was used as the ion-pairing agent to improve the derivatization process. Afterwards, the solid-phase microextraction (SPME) procedure coupled with gas chromatography with tandem mass spectrometers (GC/MS/MS) was performed to measure the HAAs derivatives and THMs in the sample. RESULTS: A total of 92 single RTE ingredients were analyzed in this study. Among various THMs and HAAs, the results showed that dibromochloromethane (21%) and dichloroacetic acid (12%) had the highest detection rates, respectively. Compared with fruits, vegetables were more easily to contain DBPs. For adults in Taiwan, the maximum daily exposure of THMs and HAAs estimated via the consumption of RTE vegetables were 28.53 and 77.83 µg, respectively. SIGNIFICANCE: The findings from this study suggest that the exposure of DBPs from RTE vegetables is an important food safety issue in Taiwan.

Polo­like kinase 1 selective inhibitor BI2536 (dihydropteridinone) disrupts centrosome homeostasis via ATM­ERK cascade in adrenocortical carcinoma.

Adrenocortical carcinoma (ACC) is a rare but malignant tumor. Surgical removal, radiotherapy and combined chemotherapy are commonly used to treat ACC. Despite efforts for several decades, the mortality rate of ACC remains high after treatments. Therefore, identifying a novel therapeutic molecule is important to increase the survival rate of patients with ACC. The centrosome is a microtubule organizing center, and it also functions as a signaling hub to coordinate cell cycle progression. Deficiencies in the regulation of centrosome copy numbers may cause cell cycle arrest or even apoptosis. BI2536 is a polo like kinase 1­selective inhibitor and has been tested for the treatment of several types of cancer, including lung, oral and gastric cancer. However, to the best of our knowledge, its effects on ACC have not yet been examined. The present study revealed that BI2536 inhibited Y1 ACC cell proliferation in a time­ and dose­dependent manner. BI2536 blocked cell cycle progression and also induced cell apoptosis as shown by flow cytometry. Furthermore, following BI2536 treatment, centrosome amplification was induced, which resulted in aberrant mitosis. In terms of the mechanism, BI2536 induced DNA damage as evidenced by γH2AX staining and comet assay, followed by activation of ATM serine/threonine kinase­ERK signaling to promote centrosome amplification. Therefore, the present study suggested that BI2536 could be used as an adjuvant therapy in the treatment of ACC, and also revealed the underlying molecular mechanism.

Indoor Air Pollution Increases the Risk of Lung Cancer.

(1) Background: Cooking and burning incense are important sources of indoor air pollutants. No studies have provided biological evidence of air pollutants in the lungs to support this association. Analysis of pleural fluid may be used to measure the internal exposure dose of air pollutants in the lung. The objective of this study was to provide biological evidence of indoor air pollutants and estimate their risk of lung cancer. (2) Methods: We analyzed 14 common air pollutants in the pleural fluid of 39 cases of lung adenocarcinoma and 40 nonmalignant controls by gas chromatography-mass spectrometry. (3) Results: When we excluded the current smokers and adjusted for age, the adjusted odds ratios (ORs) were 2.22 (95% confidence interval CI = 0.77-6.44) for habitual cooking at home and 3.05 (95% CI = 1.06-8.84) for indoor incense burning. In females, the adjusted ORs were 5.39 (95% CI = 1.11-26.20) for habitual cooking at home and 6.01 (95% CI = 1.14-31.66) for indoor incense burning. In pleural fluid, the most important exposure biomarkers for lung cancer were naphthalene, ethylbenzene, and o-xylene. (4) Conclusions: Habitual cooking and indoor incense burning increased the risk of lung adenocarcinoma.

Biological monitoring of low-level 2-butoxyethanol exposure in decal transfer workers in bicycle manufacturing factories.

OBJECTIVES: In this study, exposures to ethylene glycol monobutyl ether (or 2-butoxyethanol, 2-BE) in decal transfer workers in the bicycle manufacturing industry were investigated. Personal air sampling and biological monitoring were used to assess total uptake through inhalation and dermal exposure. Haemoglobin was also analysed to evaluate the effects of exposure on the haematopoietic system. METHODS: 80 workers in two bicycle factories completed a questionnaire. NIOSH method 1403 was adopted for air sampling and analysis of 2-BE. Prework and postwork urine samples were also collected for determination of total 2-butoxyacetic acid (BAA) after hydrolysis. Haemoglobin tests were performed using an automated haemoglobin analysis system. RESULTS: The 31 decal transfer workers whose hands were in direct contact with a dilute aqueous solution of 2-BE, were exposed to an average of 1.7 ppm (8.1 mg/m(3)) of 2-BE in air. Correlation of 2-BE in air and postshift urinary BAA levels (after hydrolysis) was poor. Postshift total BAA levels in urine on Monday and Friday (446.8 and 619.4 mg/g creatinine) were around 223% and 310% of the ACGIH proposed Biological Exposure Index (BEI; 200 mg/g creatinine). Higher levels of total BAA were observed in the urine of subjects exposed to low-level 2-BE in air, presumably because of direct dermal contact. CONCLUSIONS: The mean preshift BAA on Friday was significantly higher than that on Monday, implying that the more days of exposures, the higher the accumulation. Since accumulation occurred with low-level exposure to 2-BE, it is recommended that urine samples be collected at the end of the working week.

The investigation of the volatile metabolites of lung cancer from the microenvironment of malignant pleural effusion.

For malignant pleural effusions, pleural fluid cytology is a diagnostic method, but sensitivity is low. The pleural fluid contains metabolites directly released from cancer cells. The objective of this study was to diagnose lung cancer with malignant pleural effusion using the volatilomic profiling method. We recruited lung cancer patients with malignant pleural effusion and patients with nonmalignant diseases with pleural effusion as controls. We analyzed the headspace air of the pleural effusion by gas chromatography-mass spectrometry. We used partial least squares discriminant analysis (PLS-DA) to identify metabolites and the support vector machine (SVM) to establish the prediction model. We split data into a training set (80%) and a testing set (20%) to validate the accuracy. A total of 68 subjects were included in the final analysis. The PLS-DA showed high discrimination with an R2 of 0.95 and Q2 of 0.58. The accuracy of the SVM in the test set was 0.93 (95% CI 0.66, 0.998), the sensitivity was 83%, the specificity was 100%, and kappa was 0.85, and the area under the receiver operating characteristic curve was 0.96 (95% CI 0.86, 1.00). Volatile metabolites of pleural effusion might be used in patients with cytology-negative pleural effusion to rule out malignancy.

Characterization of volatile organic compounds in the vicinity of an optoelectronics industrial park in Taiwan.

This study aimed to determine the concentration of volatile organic compounds (VOCs) and investigate the impacts of traffic and industrial activities on the concentration of VOCs near the Central Taiwan Science Park (CTSP) in Taiwan during 2005. Twelve-hour canister sampling was performed at 10 sites near CTSP every season. Samples were analyzed by gas chromatography with a mass-selective detector. The traffic flow rate, industrial production rates, and meteorological information were also collected to assess their impacts on VOC concentrations using multiple linear regression models. The major components determined in the atmosphere were toluene (29.4-218.8 microg m(-3)), acetone (30-71.3 microg m(-3)), m/p-xylene (7.8-51.7 microg m(-3)), and ethanol (16.4-47.8 microg m(-3)); only ethanol revealed a pattern of increasing concentration from spring to winter. The log-transformed mean concentrations of toluene, acetone, and ethanol were significantly associated with the production rates of the optoelectronic companies after adjustment for traffic flow and meteorological factors (P < 0.05). There was no significant association between the total traffic flow rate and any log-transformed mean concentrations of VOCs. Each $1 million (U.S.) increase in optoelectronic sales was significantly associated with increasing mean concentrations of 1.29 +/- 1.08 microg m(-3) for toluene, 1.13 +/- 1.05 microg m(-3) for acetone, and 1.25 +/- 1.09 microg m(-3) for ethanol. The authors' findings suggest that optoelectronic industrial activities are still the predominant source for VOC emissions surrounding this industrial park.

Cordycepin Inhibits Human Gestational Choriocarcinoma Cell Growth by Disrupting Centrosome Homeostasis.

INTRODUCTION: Human gestational choriocarcinoma, a type of gestational trophoblastic disease, occurs after miscarriage, abortion, ectopic pregnancy, or molar pregnancy. Despite recent advances in the mechanism of anticancer drugs that induce human gestational choriocarcinoma apoptosis or block its growth, new therapeutic approaches are needed to be established. Cordycepin is an active anti-cancer component extracted from Cordyceps sinensis. It prevents cell proliferation both in vitro and in vivo. MATERIALS AND METHODS: Here, we examined cell growth by counting cell numbers, and performing a flow cytometry assay and EdU incorporation assay. Centrosome and cytoskeleton-related structures were observed by immunofluorescence assay. The DNA damage-related signaling was examined by Western blot assay. RESULTS: Here, we showed that cordycepin inhibited human gestational choriocarcinoma cell proliferation and induced cell death. In addition, treatment with cordycepin activated DNA-PK and ERK, thus inducing centrosome amplification and aberrant mitosis. These amplified centrosomes also disrupted microtubule arrays and actin networks, thus leading to defective cell adhesion. Furthermore, cordycepin induced autophagy for triggering cell death. CONCLUSION: Thus, our study demonstrates that cordycepin inhibits cell proliferation and disrupts the cytoskeleton by triggering centrosome amplification.

Vertical distribution of source apportioned PM2.5 using particulate-bound elements and polycyclic aromatic hydrocarbons in an urban area.

Receptor models have been widely used for identifying and quantifying source-specific contributions from mixtures of air pollutants. Nonetheless, our knowledge is still limited on how various components of air pollution are vertically distributed and the sources of such pollutants. In this study, we collected 135 samples of PM2.5 (particles with aerodynamic diameter less than or equal to 2.5 µm) from building balconies at three altitudes in the metropolis of Taipei (Taiwan) and analyzed the samples for elements and polycyclic aromatic hydrocarbons that could be used to identify the sources of those pollutants. We used positive matrix factorization (PMF) to identify seven likely sources, including combustion, sulfur-rich aerosol, fresh traffic, industry/Cr-rich, oil combustion/vehicle, dust, and traffic. Although PM2.5 mass differed significantly between low-level and mid-level sites, the largest contributor to PM2.5 mass (sulfur-rich aerosol, 35.2%) showed nonsignificant variation in the vertical distribution. In contrast, oil combustion/vehicle, which exhibited significant difference between mid-level sites and the other two altitudes, might be a determinant in the vertical variation of PM2.5. We also observed negative trends with sampling height for combustion and traffic emissions.

A novel lung alveolar cell model for exploring volatile biomarkers of particle-induced lung injury.

Quartz can increase oxidative stress, lipid peroxidation, and inflammation. The objective of this study was to explore the volatile biomarkers of quartz-induced lung injury using a lung alveolar cell model. We exposed the human alveolar A549 cell line to 0, 200, and 500 µg/mL quartz particles for 24 h and used gas chromatography-mass spectrometry to measure the volatile metabolites in the headspace air of cells. We identified ten volatile metabolites that had concentration-response relationships with particles exposure, including 1,2,4-oxadiazole, 5-(4-nitrophenyl)-3-phenyl- (CAS: 28825-12-9), 2,6-dimethyl-6-trifluoroacetoxyoctane (CAS: 61986-67-2), 3-buten-1-amine, N,N-dimethyl- (CAS: 55831-89-5), 2-propanol, 2-methyl- (CAS: 75-65-0), glycolaldehyde dimethyl acetal (CAS: 30934-97-5), propanoic acid, 2-oxo-, ethyl ester (CAS: 617-35-6), octane (CAS: 111-65-9), octane, 3,3-dimethyl- (CAS: 4110-44-5), heptane, 2,3-dimethyl- (CAS: 3074-71-3) and ethanedioic acid, bis(trimethylsilyl) ester (CAS: 18294-04-7). The volatile biomarkers are generated through the pathways of propanoate and nitrogen metabolism. The volatile biomarkers of the alkanes and methylated alkanes are related to oxidative and lipid peroxidation of the cell membrane. The lung alveolar cell model has the potential to explore the volatile biomarkers of particulate-induced lung injury.

Sclera-related gene polymorphisms in high myopia.

PURPOSE: Transforming growth factor-beta2 (TGF-beta2), basic fibroblast growth factor (bFGF), and fibromodulin (FMOD) are important extracellular matrix components of the sclera and have been shown to be associated with the development of high myopia. Our aim was to examine the association between myopia and the polymorphisms within TGF-beta2, bFGF, and FMOD. METHODS: The study group comprised of patients (n=195; age range: 17-24 years) with a spherical equivalent of -6.5 diopters (D) or a more negative refractive error. The control group comprised of individuals (n=94; age range: 17-25 years) with a spherical equivalent ranging from -0.5 D to +1.0 D. The subjects with astigmatism over -0.75 D were excluded from the study. High resolution melting (HRM) genotyping and restriction fragment length polymorphism (RFLP) genotyping were used to detect single nucleotide polymorphisms (SNPs). The polymorphisms detected were TGF-beta2 (rs7550232 and rs991967), bFGF (rs308395 and rs41348645), and FMOD (rs7543418). Moreover, a stepwise logistic regression procedure was used to detect which of the significant SNPs contributed to the main effects of myopia development. RESULTS: There were significant differences in the frequency of the A allele and A/A genotype in TGF-beta2 (rs7550232; p=0.0178 and 0.03, respectively). Moreover, the haplotype distribution of haplotype 2 (Ht2; A/A) of TGF-beta2 differed significantly between the two groups (p=0.014). The results of the stepwise logistic regression procedure revealed that TGF-beta2 (rs7550232) contributed significantly to the development of high myopia. CONCLUSIONS: TGF-beta2 is an important structure of sclera and might contribute to the formation of myopia. TGF-beta2 (rs7550232) polymorphisms, A allele and A/A genotype, had a protective role against the development of high myopia.

Muscarinic acetylcholine receptor 1 gene polymorphisms associated with high myopia.

PURPOSE: Numerous studies, including those using animal models of myopia development and human clinical trials, have shown that the non-selective muscarinic antagonist atropine is effective in preventing the axial elongation that leads to myopia development. Among all of the muscarinic acetylcholine receptors (mAChRs), mAChR 1 (M1) was the most effective in preventing myopic eye change. Our specific aim in this study was to examine the association between high myopia and polymorphisms within the muscarinic acetylcholine receptors 1 gene (CHRM1). METHODS: The participants comprised of a high myopia group (n=194; age range, 17-24 years) having a myopic spherical equivalent greater than 6.5 diopters (D) and a control group (n=109; age range, 17-25 years) having a myopic spherical equivalent less than 0.5 D. Genotyping was performed using an assay-on-demand allelic discrimination assay. Polymerase chain reaction (PCR) was performed using 96 well plates on a thermal cycler. The polymorphisms detected were S1 (CHRM1rs11823728), S2 (CHRM1rs544978), S3 (CHRM1rs2186410), and S4 (CHRM1rs542269). RESULTS: There was a significant difference in the distribution of S2 and S4 between the high myopia and control groups (p=2.40 x 10(-6) and 2.38 x 10(-8), respectively). The odds ratios of AA genotype of S2 and GG genotype of S4 were both 0.08 (95% confidence interval [CI]: 0.02-0.29 and 0.02-0.36, respectively). Logistic regression test revealed S1, S2, and S4 CHRM1 as all being significant in the development of high myopia. Moreover, the distributions of haplotype 4 (Ht4; C/A/A/A) differed significantly between the two groups (p=3.4 x 10(-5), odds ratio: 0.1, 95% CI: 0.03-0.34). CONCLUSIONS: Our results suggest that the S2 and S4 polymorphisms of CHRM1 are associated with susceptibility for developing high myopia. S1, S2, and S4 CHRM1 had a co-operative association with high myopia.

Assessment of dermal exposures for synthetic musks from personal care products in Taiwan.

Over the past decades, synthetic musks have been widely used as fragrances for enhancing scent and covering odor in many personal care products (PCPs). The presence of synthetic musk is of potential concern since health effects, such as photo-allergic reactions and neurotoxicity due to the exposures have been observed. To assess the associate health risks from possible exposures of synthetic musks in Taiwan, headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography/tandem mass spectrometers (GC/MS/MS) in multiple reaction monitoring (MRM) mode was used to determine 10 synthetic musks in total 109 PCPs samples. The results showed that the higher levels of synthetic musks were found in perfume, body lotion and hair care products. Galaxolide (HHCB) and Tonalide (AHTN) were found in every category of the PCPs samples. The median concentrations in 109 samples measured were 958.19 µg g-1 and 674.03 µg g-1 for HHCB and AHTN, respectively. Cashmeran (DPMI) was also found in all the samples collected with a median concentration of 144.62 µg g-1, except for categories of facial essences. Musk ketone (MK) was found in several PCPs categories, including perfume, body lotion, hair care product, and shower bath products, with a median concentration of 693.27 µg g-1. In addition, dermal exposures of synthetic musks were also estimated for people in Taiwan. The daily exposure of total synthetic musks through applications of PCPs was estimated to be 22.54 µg kg-1 body weight day-1. The results indicate that the skin contact of perfume and body lotion were the major sources for human exposures to synthetic musks in Taiwan.

Determinations and residual characteristics of triclosan in household food detergents of Taiwan.

Triclosan (2,4,4'-trichloro-2'-hydroxydiphenyl ether) is a widely used antibacterial agent. However, it was concerned recently that triclosan might act as an antibiotic and will cause resistant bacterial strains. Furthermore, possible formation of toxic chloroform was also reported when the triclosan contained in household dishwashing soaps reacted with the chlorinated water. To assess the associate risks from possible exposures, concentrations of triclosan in household food detergents of Taiwan were determined in this study. High performance liquid chromatography (HPLC) with UV detector at 280 nm was used to analyze the triclosan in samples. Factors that might affect the residual characteristics of triclosan from detergents on dishware and fruits, including the concentrations of detergents used, the temperature and immersion time for water before the cleaning processes, the temperatures of water used for the cleaning processes, and the materials of dishware made of, were evaluated under the orthogonal experiment design by the Taguchi method. By the analysis of variance, the orders of importance of different parameters were determined. The concentrations of triclosan detected in household food detergents were found to be 1.7 x 10(-2) -5.6 x 10(-1) (triclosan/detergent, mg g(-1)). For residual characteristics, the concentration of detergents used as well as the materials of dishware were found to be the significant factors that will affect the triclosan left on the dishware. On the other hand, the concentration of triclosan in the detergents was found to be the only factor that will affect the triclosan left on fruits. The maximum dose of triclosan exposures from the use of household food detergents in Taiwan was also estimated in the study.

Determining the Residual Characteristics of Alkylphenols, Arsenic, and Lead as well as Assessing the Exposures of 1,4-Dioxane from Household Food Detergents.

Food detergents are commonly used in households. The main components of detergents include surfactants and water. It has been found that certain compounds, which may cause health concerns, appear in food detergents, such as alkylphenols, arsenic, and lead. After applying food detergents is when people may be exposed to various levels of these chemicals when there are residues. In this study, the Taguchi experimental design was performed to determine the possible factors that might affect the residual characteristics of food detergent on dishware, fruits, and vegetables. The results showed that the variety of detergent was found to be the most significant factor affecting the residue amounts of arsenic (62.9%) and lead (71.6%) on fruits and vegetables, whereas the concentration of detergent used affected the amount of lead residue only (10.5%). On the other hand, dishware material, the concentration of analytes, immersion time, and type of surfactant contributed to arsenic residues on dishware, whereas technical nonylphenol isomer residues on dishware increased as the concentration of spiked analyte increased. In addition, the occurrence of 1,4-dioxane, a possible human carcinogen, in household food detergents in Taiwan was also determined in this research by solid-phase microextraction and GC-MS. Among the 80 detergent samples, 71 contained different concentrations ranges of 1,4-dioxane, from 0.03 to ~3.73 µg/g. In the exposure assessment, it was estimated that the maximum amounts of 1,4-dioxane in contact with the skin from the use of household food detergent in Taiwan was 0.015 µg/kg/day.

Source apportionment of urban air pollutants using constrained receptor models with a priori profile information.

Exposure to air pollutants such as volatile organic compounds (VOCs) and fine particulate matter (PM2.5) are associated with adverse health effects. This study applied multiple time resolution data of hourly VOCs and 24-h PM2.5 to a constrained Positive Matrix Factorization (PMF) model for source apportionment in Taipei, Taiwan. Ninety-two daily PM2.5 samples and 2208 hourly VOC measurements were collected during four seasons in 2014 and 2015. With some a priori information, we used different procedures to constrain retrieved factors toward realistic sources. A total of nine source factors were identified as: natural gas/liquefied petroleum gas (LPG) leakage, solvent use/industrial process, contaminated marine aerosol, secondary aerosol/long-range transport, oil combustion, traffic related, evaporative gasoline emission, gasoline exhaust, and soil dust. Results showed that solvent use/industrial process was the largest contributor (19%) to VOCs while the largest contributor to PM2.5 mass was secondary aerosol/long-range transport (57%). A robust regression analysis showed that secondary aerosol was mostly contributed by regional transport related factor (25%).

Diffusive sampling of airborne furfural by solid-phase microextraction device with on-fiber derivatization.

The solid-phase microextraction (SPME) device was used as a diffusive sampler for airborne furfural. The polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber was used, and O-2,3,4,5,6-(pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) was first loaded onto the fiber. The SPME fiber assembly was then inserted into a PTFE tubing as a diffusive sampler. Known concentrations of furfural around the threshold limit values (TLVs)/time-weighted average and specific relative humidities (RHs) were generated by syringe pumps in a dynamic generation system. Validations of the SPME diffusive sampling with the US Occupational Safety and Health Administration (OSHA) organic method 72 were performed side-by-side in an exposure chamber at 25 degrees C. Gas chromatography/mass spectrometry (GC/MS) was used for sample analysis. The experimental sampling constant of the sampler was found to be (1.75 +/- 0.03) x 10(-2) (cm3 min(-1)) at 25 degrees C, whereas face velocity (0-0.25 ms(-1)) as well as RHs (10-80%) were proven to have no effects on the sampler. The correlations between the results from both SPME device and OSHA organic method 72 were found to be linear (r = 0.9849) and consistent (slope = 0.99 +/- 0.03). However, the variations of diffusion coefficients at different temperatures needs to be considered, and the adjustment of sampling constant was a must when sampling at temperatures different from 25 degrees C.

Increased prevalence of interleukin-1 receptor antagonist gene polymorphism in patients with chronic rhinosinusitis.

OBJECTIVE: To assess the association of the interleukin (IL)-1beta and the IL-1 receptor antagonist (IL-1Ra) gene polymorphisms with chronic rhinosinusitis (CRS). DESIGN: Genotyping of the 2 IL-1beta gene (IL1B) polymorphisms (promoter and exon) and the IL-1Ra gene (IL1RN) polymorphism (intron 2) was performed using polymerase chain reaction and restriction length fragment polymorphism analyses. SETTING: Prospective study, tertiary medical center. PATIENTS: The study population comprised 88 consecutive adult Taiwan-Chinese patients who met stringent criteria for CRS and received endoscopic sinus surgery and 103 healthy volunteers of the same ethnicity and similar age range. Of the 88 patients, 61 had CRS with nasal polyps, while the other 27 had CRS without nasal polyps. RESULTS: There were significant differences in the distribution of the IL1RN polymorphism between the control subjects and patients with CRS (P<.05). The II allele of IL1RN occurred more frequently in the CRS patient group, and the odds ratio for subjects with I/II genotype was 3.39 (95% confidence interval, 1.25-9.18). In the case of CRS without nasal polyps, the odds ratio for subjects with I/II genotype was further increased to 4.75 (1.39-16.25). There was no association between the other 2 polymorphisms of IL1B and CRS. CONCLUSION: Increased prevalence of IL1RN polymorphism in patients with CRS suggests that this polymorphism, or a polymorphism in linkage disequilibrium with it, may be involved in the development of CRS.