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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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%).

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.

Determinations of airborne synthetic musks by polyurethane foam coupled with triple quadrupole gas chromatography tandem mass spectrometer.

Synthetic musk is widely used in various scented consumer products. However, the exposure via inhalation is often ignored due to pleasant smells. In addition, the information regarding the distribution of synthetic musk in air is limited. Hence, this research is aimed to develop a highly sensitive and widely applicable method for the determination of airborne synthetic musk. In this study, polyurethane foam (PUF) and filter were employed for active air sampling. Microwave assisted extraction (MAE) and nitrogen evaporator were performed for sample preparation. A gas chromatography coupled with triple quadrupole tandem mass spectrometer (GC/MS-MS) with specific multiple reaction monitoring (MRM) transition pairs was applied for sample analysis. Compared with using selected ion monitoring (SIM) mode traditionally, the sensitivities were improved in this study about an order at least. In terms of air concentration, as low as 0.48ngm(-3) can be determined when sampling at 3.5Lmin(-1) for 8h. The method established was further applied to the analysis of synthetic musk compounds in air samples collected in a cosmetics plant. The results showed that the airborne concentrations of gaseous polycyclic musk, gaseous nitro-musk, and particle-phase polycyclic musk were 6.4×10(2), 4.0×10(1) and 3.1×10(2)ngm(-3), respectively. Meanwhile, Cashmeran, Celstolide, Galaxolide, and Tonalide were found as the dominant musk compounds in the factory investigated.

Occupational exposures of airborne trichloramine at indoor swimming pools in Taipei.

Ten indoor swimming pools in Taipei, Taiwan were included in the study to assess the exposure of people to airborne trichloramine (NCl3) and also to discover the factors that might affect the associated concentrations. An active air sampling method was performed to determine the levels of NCl3, while questionnaires were administered to swimming pool workers, including lifeguards, swimming instructors, and management employees. The results show that the concentrations of trichloramine ranged from 0.017 to 0.15 mg m(-3), which were generally lower than what have been reported from other studies. Symptoms of sore throat and phlegm were more frequent among lifeguards and swimming instructors (exposure group) than management employees (reference group) (odds ratios were 11.28 and 4.22 for sore throat and phlegm, respectively). It seems that the current exposure limit for airborne NCl3, which was recommended by WHO, was not lower enough to protect the health of pool attendants. Regulated level of free available chlorine in Taipei (i.e., 0.3-0.7 ppm) is lower than what is required in other countries (e.g., 1-3 ppm in the UK). This might be the main reason why the concentrations of NCl3 reported elsewhere were higher than what were found in this research. Further international comparisons will help to elucidate if low free chlorine concentration should be adopted as an operating standard. For the indoor swimming pools in Taipei, the air quality is suggested to be improved, since even with the low concentrations of NCl3, higher respiratory ailments among pool workers were observed.

Evaluation of the relationship between urodynamic examination and urinary tract infection based on urinalysis results.

OBJECTIVE: To determine risk factors for urinary tract infection (UTI) after urodynamic examination by evaluating patients' clinical characteristics and urodynamic parameters. MATERIALS AND METHODS: Two hundred and sixty-one female patients (mean age 58.7 ± 12.3 years) from May to December 2011 who had lower urinary tract symptoms or needed definite diagnosis before pelvic floor reconstruction or anti-incontinence surgery received urodynamic examination. All patients received urinalysis on the scheduled day of urodynamic examination and 3 days after urodynamic examination. Mid-stream urine samples were obtained for urinalysis before urodynamic examination. If patients had UTI based on our urinalysis criteria before urodynamic examination, the investigation was postponed until the patient had a 3-7-day course of antibiotic treatment and urinalysis showed no UTI. RESULTS: Among 261 patients, 19 and 51 patients had UTI before and after urodynamic examination, respectively. Our data suggest that urodynamic examination causes significantly increased incidence of UTI. Increased number of vaginal births, UTI before investigation, diabetes and decreased average flow rate are risk factors for UTI after urodynamic examination. CONCLUSION: When the prevalence of UTI after urodynamic examination is higher than 10%, we recommend that prophylactic antibiotics should be given for high-risk patients with parameters such as older age, diabetes and multipara (>3). Those who have UTI before urodynamic examination and who are found to have a low average flow rate of less than 7 mL/second should take prophylactic antibiotics after examination.

Low-lying-implantation ectopic pregnancy: a cluster of cesarean scar, cervico-isthmus, and cervical ectopic pregnancies in the first trimester.

OBJECTIVE: To describe the treatment outcomes of aberrant ectopic implantations in the lower segment of the uterus in a cohort population and to evaluate whether or not low-lying-implantation ectopic pregnancy (LLIEP), a new term, is appropriate to include in the traditional diagnoses of cervical pregnancy (CP), cesarean scar pregnancy (CSP), and other unusual aberrant implantations in the lower segment of the uterus in the first trimester, in terms of clinical characteristics, treatment, and prognosis. MATERIALS AND METHODS: Forty-two women with ectopic pregnancies of <12 weeks' gestational age from July 2003 to December 2008 were prospectively studied. Each patient underwent an ultrasound evaluation by an experienced consultation team and was grouped into the CP, CSP, or cervico-isthmic pregnancy (CIP) group. Patients underwent either suction dilatation and curettage (D and C) alone, or laparoscopic uterine artery blockage followed by suction D and C, to remove the aberrant trophoblasts without other adjuvant treatments. Clinical characteristics and biochemical factors, including obstetric history, patient age, body mass index (BMI), gestational age, serum hematocrit and ß-hCG level, operation method, operation time, and intraoperative blood loss were evaluated. RESULTS: There were no significant differences in patient age (mean = 34.1 ± 6.4 years), previous number of cesarean deliveries (mean = 1.5 ± 0.8), gestational age (mean = 6.9 ± 1.2 weeks), serum ß-hCG (mean = 35,384.3 ± 41,726.9 mIU/mL), operation time (mean = 60.3 ± 46.6 minutes), and surgical blood loss (mean = 124.7 ± 191.5 mL) among the three patient groups. The uterus was successfully preserved in all patients after treatment. CONCLUSION: The prognosis of surgical management for ectopic implantations in the lower segment of the uterus is good. The new term LLIEP seems appropriate to cover all forms of aberrant ectopic implantations in the lower segment of the uterus in the first trimester, in terms of treatment efficacy. The use of LLIEP for preoperative ultrasound diagnosis would enable the clinician to diagnose unusual cases more easily, without the need to change the current treatment policy.

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.

Assessment of dietary furan exposures from heat processed foods in Taiwan.

Furan has been demonstrated to be formed in a variety of heat processed foods. The presence of furan is of potential health concern because it has been classified as 'possibly carcinogenic to humans' by the International Agency for Research on Cancer (IARC). To assess the associate risks from possible exposures in Taiwan, headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography/mass spectrometer (GC/MS) was used to determine furan in a variety of food samples. Due to matrix effects, standard addition method was selected to be performed in this study. More than 100 processed foods were analyzed, and the results showed that the concentrations of furan ranged from 0.4ngg(-1) to 150ngg(-1) in various kinds of samples. Higher furan levels were found principally in the categories of baby foods, coffees, sauces and broths. Exposures from different food varieties were also estimated. As for adults in Taiwan, the average daily intakes of furan were estimated to be 299.89ngkg(-1) body weight d(-1) for male, and 177.18ngkg(-1) body weight d(-1) for female. For a 6-month-old baby, the daily intake was estimated to be 0.05-0.56, and 0.11-3.42microgkg(-1) body weight d(-1) from infant formula and baby food, respectively. To avoid possible exposure, safety precautions such as heating in an open can and applying stirring are recommended to lower the furan level in foods.

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.