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Volatile organic compounds (VOCs) are continuously emitted into the atmosphere from natural and anthropogenic sources and rapidly spread from the atmosphere to different environments. A large group of VOCs has been included in the class of air pollutants; therefore, their determination and monitoring using reliable and sensitive analytical methods represents a key aspect of health risk assessment. In this work, an untargeted approach is proposed for the evaluation of the exposure to volatile organic compounds of workers in an engine manufacturing plant by GC–MS measurements, coupled with solid-phase microextraction (SPME). The analytical procedure was optimized in terms of SPME fiber, adsorption time, desorption time, and temperature gradient of the chromatographic run. For the microextraction of VOCs, the SPME fibers were exposed to the air in two different zones of the manufacturing factory, i.e., in the mixing painting chamber and the engine painting area. Moreover, the sampling was carried out with the painting system active and running (system on) and with the painting system switched off (system off). Overall, 212 compounds were identified, but only 17 were always present in both zones (mixing painting chamber and engine painting area), regardless of system conditions (on or off). Finally, a semi-quantitative evaluation was performed considering the peak area value of the potentially most toxic compounds by multivariate data analyses. [ABSTRACT FROM AUTHOR]

The aromatic odor of Plectranthus hadiensis var. tomentosus has been found to have the potential to improve physical and mental health of people in indoor environment, but its effectivess is reduced for that the release of volatile organic compounds from plants is susceptible to indoor environmental changes. The purpose of this study was to investigate the response of volatile organic compounds released by P. hadiensis var. tomentosus to common indoor environmental changes, and to provide a scientific basis for its efficient and sustainable application in building a comfortable pro-biotic environment to improve the physical and mental health of indoor personnel. Thus, the effects of four typical indoor environmental factors, such as air temperature, air relative humidity, CO2 concentration and light variation, on the release of volatile organic compounds from P. hadiensis var. tomentosus were investigated in this study. And the dynamic headspace and gas chromatography-mass spectrometry techniques were used to analyze the volatile organic compounds in different indoor environments with an environmental control device based on mixed-level orthogonal array design. The results were as follows:(1)Among the four typical indoor environmental factors of air temperature, air relative humidity, CO2 concentration and light condition, CO2 concentration and air temperature had greater effects on the release of volatile organic compounds from P. hadiensis var. tomentosus, while the effects of air relative humidity and light were weak.(2)For P. hadiensis var. tomentosus cultivated under normal photoperiod, an environmental condition with CO2 concentration of 500 μmol·mol-1, air temperature of 25 ℃ and air relative humidity of 60% was the most suitable for releasing volatile organic compounds from P. hadiensis var. tomentosus in the absence of light. Under this environmental condition, the total amount of volatile organic compounds released by P. hadiensis var. tomentosus was 86.23 μg·L-1·kg-1, and the content of biological active components with potentials for the positive intervention of physical and mental health was 78.03 μg·L-1·kg-1. In summary, the results suggest that when the aroma plant P. hadiensis var. tomentosus is used to build an indoor pro-biotic environment to maintain or improve the physical and mental health of people in indoor, the environmental conditions should be controlled properly, especially CO2 concentration and air temperature, so as to fully and efficiently produce the positive health benefits from P. hadiensis var. tomentosus. [ABSTRACT FROM AUTHOR]

The emission characteristics of VOCs (volatile organic compounds) from laminate flooring were investigated and their impacts on indoor environment evaluated in order to provide basic data for the study of harmful gas release from laminate flooring, and to provide reference for producers and consumers to evaluate their effects on indoor air quality. In this study, Shuang Xiang laminate flooring was selected and sampled with 1 m 3 climate chamber method. The sampled VOCs were analyzed by GC-MS (gas chromatography-mass spectrometry) and according to the forestry industry standards LY/ T 3230-2020 “Classification of volatile organic compound emissions contents from wood-made panels and their finishing products” and LY/ T 3229 - 2020 “ Specification for indoor carrying capacity of wood-based panels and finishing products based on volatile organic compounds emission”, the laminate flooring on indoor air quality was evaluated. Results showed that the TVOC release of this laminate flooring gradually decreased with time and reached the release equilibrium at day 28. The VOCs released were mainly olefins, aromatic hydrocarbons and alkanes, with small amounts of aldehydes, ketones, lipids and alcohols. In one cycle, the release level of naphthalene on the 3rd day of the laminate flooring did not meet the Class I standard, and the release levels of several major pollutants were Class I at the rest of the time. VOCs composite index of laminate flooring decreased with the increase of time after the 3rd day, and according to the composite index grading standard, the VOCs release class of laminate flooring on the 3rd day was Class Ⅱ, and the indoor air quality was qualified, and the VOCs release class of the rest of the time was Class I, and the indoor air quality was excellent. The TVOC release rate of this laminate flooring gradually decreased with time, in line with the mass transfer principle. After the VOCs were released in equilibrium, the release class is in line with Class I. The calculated composite index was in line with Class I. The indoor air quality was excellent and consumers can use it with confidence [ABSTRACT FROM AUTHOR]

Very volatile organic compounds (VVOCs) are a group of important odor pollutants affecting indoor air quality that have been shown to be harmful to human health. A 15 L environmental chamber, combined with multi-bed tube was used to collect gases. Fifteen very volatile organic compounds (VVOCs), including 12 odor compounds, were identified from veneered medium density fiberboard coated with water-based lacquer (WB-MDF) using gas chromatography–mass spectrometry/olfactometry (GC-MS/O). The total very volatile organic compound (TVVOC) and total odor intensity (TOI) showed a decreasing trend over time, reaching equilibrium on day 28. TVVOC showed an overall slow-fast-slow emission profile, from day 3 to day 7, with a maximum decay rate of 29.7%. TOI showed the greatest rate of decline from day 1 to day 3, at approximately 12%. Alkane and alcohol VVOCs were the more abundant compounds, accounting for at least 60% and even up to 80% of the total. The major odor impression was fruity, with a highest odor rating of 6.6, followed by sweet, with an odor rating of 6.1. Although the odor impression changed from sweet to fruity over time, it seemed pleasant overall. The odor contributors were mainly alkanes, alcohols, esters, and ethers, which had relatively high odor intensities. The main odor-contributing substances were dichloromethane, ethanol, ethyl acetate, 2-methylacrylic acid methyl ester, and tetrahydrofuran. When WB-MDF is used for furniture or other decorative materials, it is strongly recommended that it be stored under ventilation for at least 28 days and the adoption of substitute solvents of lacquers, modified adhesives, and low-odor wood raw materials is recommended. These possible initiatives would contribute to the aim of building an environmentally friendly indoor environment. [ABSTRACT FROM AUTHOR]

A prototype air purifier (AP) module has been constructed using bismuth-doped titanium dioxide (Bi x -P25: x(%) as Bi/Ti molar ratios of 1.1, 2.1, 3.3, 5.3, and 8.7). The reactive adsorption property of Bi x -P25 materials is evaluated against H 2 S gas at a recirculation rate of 160 L min−1 in a 17 L closed chamber. The AP (Bi 5.3 -P25) exhibits superior performance against 10 ppm H 2 S in dry air under dark conditions (i.e., without light irradiation), with a removal efficiency (X H2S)= 99% in 5 mins, reaction kinetic rate (r (at X = 10%))= 7.3 mmol h−1g−1, and partition coefficient= 0.18 mol kg−1 Pa−1. As such, its superiority is evident over the reference AP (P25) filter with X H2S < 10%. The clean air delivery rate (CADR) of AP (Bi 5.3 -P25) increases noticeably from 9.9 to 17.8 L min−1 with increasing relative humidity (RH) from 0 to 80%, respectively. In contrast, the CADR decreases from 9.9 to 5.8 L min−1 as the H 2 S increases from 10 to 20 ppm. According to density functional theory (DFT), the presence of H 2 O vapor enhances the hydroxylation of Bi x -P25 surface to promote H 2 S mineralization through the formation of TiS 3 (i.e., thermodynamic reaction of S atom with the catalytic surface). Complete removal of H 2 S on the Bi 5.3 -P25 surface is also confirmed consistently through gas chromatography-mass spectrometry (GC-MS), in-situ diffuse reflection infrared spectroscopy (in-situ DRIFTS), and elemental analysis (EA). This work represents the first utilization of Bi x -P25 materials fabricated on an AP platform toward the desulfurization of H 2 S at room temperature (RT). The practical utility of Bi x -P25 is overall validated by its eminent role in reactive adsorption and catalytic oxidation (RACO) of H 2 S from the air. [Display omitted] • Air purifiers (AP) are useful to improve indoor air quality, health safety, and life quality. • The utility of AP (Bi x -P25) is validated for reactive adsorption and catalytic oxidation (RACO) of H 2 S under varying conditions. • The combination of Bi and P25 synergistically improves Bi x -P25 surface reactivity against H 2 S. • H 2 O vapor enhances the RACO of H 2 S onto AP (Bi x -P25) by hydroxylating the surface and facilitating the dispersion of Bi active sites for catalysis. [ABSTRACT FROM AUTHOR]

To explore the composition and potential hazards of cervical cancer surgical smoke generated by ultrasonic scalpels. Surgical smoke was collected during the cutting and coagulation of cervical cancer xenograft tumors using an ultrasonic scalpel. Surgical smoke-filtered cells were cultured and subcutaneously injected into nude mice. Cell morphology and viability were assessed by HE, Pap and trypan blue staining. HPV DNA in surgical smoke samples was identified by PCR. HPV transmission was determined by culturing HPV-negative C33A cells in HPV-positive surgical smoke-filtered medium. The cytotoxicity of surgical smoke to small airway epithelial cells (SAECs) and THP-1 cells was determined by CCK-8, MTS and LDH release assays. Volatile organic compounds (VOCs), which are present in cervical cancer surgical smoke samples obtained by laparoscopic hysterectomy, were analyzed by gas chromatography-mass spectrometry (GC–MS). Cellular debris and epithelioid cells were found in surgical smoke, but no malignant cells were observed. HPV DNA was identified in all smoke samples, and HPV genotypes were matched to those in cervical cancer cells. Coculture with HPV-positive surgical smoke-filtered medium induced an 83% (15 of 18) HPV positivity rate in C33A cells. Subculture in normal medium decreased this rate to 50% (9 of 18). The proliferation of SAECs and THP-1 cells was inhibited by smoke-filtered medium in a time-dependent manner. The concentration of total VOCs, especially benzene, toluene and xylene, in surgical smoke exceeded the standard for good indoor air quality. Cervical cancer surgical smoke contains HPV and VOCs and exhibits cytotoxicity and infectivity in vitro. Surgical smoke is an occupational hazard to health care workers. • Malignant cells were not observed in surgical smoke from cervical cancer treated with ultrasonic scalpel. • HPV were found in surgical smoke, which was capable of transmitting infection to HPV negative cervical cancer cells. • Surgical smoke inhibited cell proliferation of SAEC and THP1 cells, which may show cytotoxicity to respiratory system. • Some volatile organic compounds were found in surgical smoke, which exceeded the standard of indoor air quality. [ABSTRACT FROM AUTHOR]

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Widespread use of spray-type consumer products can raise significant concerns regarding their effects on indoor air quality and human health. In this study, we conducted non-target screening using gas chromatography-mass spectrometry (GC-MS) to analyze VOCs in 48 different spray-type consumer products. Using this approach, we tentatively identified a total of 254 VOCs from the spray-type products. Notably, more VOCs were detected in propellant-type products which are mostly solvent-based than in trigger-type ones which are mostly water-based. The VOCs identified encompass various chemical classes including alkanes, cycloalkanes, monoterpenoids, carboxylic acid derivatives, and carbonyl compounds, some of which arouse concerns due to their potential health effects. Alkanes and cycloalkanes are frequently detected in propellant-type products, whereas perfumed monoterpenoids are ubiquitous across all product categories. Among the identified VOCs, 12 compounds were classified into high-risk groups according to detection frequency and signal-to-noise (S/N) ratio, and their concentrations were confirmed using reference standards. Among the identified VOCs, D-limonene was the most frequently detected compound (freq. 21/48), with the highest concentration of 1.80 mg/g. The risk assessment was performed to evaluate the potential health risks associated with exposure to these VOCs. The non-carcinogenic and carcinogenic risks associated with the assessed VOC compounds were relatively low. However, it is important not to overlook the risk faced by occupational exposure to these VOCs, and the risk from simultaneous exposure to various VOCs contained in the products. This study serves as a valuable resource for the identification of unknown compounds in the consumer products, facilitating the evaluation of potential health risks to consumers. [Display omitted] • Non-target screening was performed to analyze VOC in spray-type consumer products. • A total of 243 VOCs were identified from non-target screening using GC/MS. • Alkanes, cycloalkanes, and monoterpenoids are frequently detected VOCs. • D-limonene was the most frequently detected VOC, with up to 1.80 mg/g. • The risk (HQ) associated with exposure to VOCs in the product was relatively low. [ABSTRACT FROM AUTHOR]

Indoor air quality problems are usually revealed by occupants' complaints. In this study, the odors of two types of hardwood species, namely, Cathy poplar (Populus cathayana Rehd.) and rubberwood (Hevea brasiliensis) were selected and extracted with ethanol-toluene for removal of extractives in an attempt to eliminate the odors. The odorous components of neat and extractedwoods were identified by gas chromatography-mass spectrometry/olfactometry (GC-MS/O). The results showed that about 33 kinds of key volatile compounds (peak area above 0.2%) were detected from the GC-MS, and about 40 kinds of odorants were identified from GC-O. The components were concentrated between 15 and 33 min in GC-O, which was different from the concentration time in GC-MS. Lots of the odors identified from GC-O were unpleasant to humans, and variously described as stinky, burnt, leather, bug, herb, etc. These odors may originate from the thermos-oxidation of wood components. After extraction, the amounts and intensities of some odorants decreased, while some remained. However, the extraction process resulted in a benzene residue and led to increased benzene odor. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are present in petroleum based products and are combustion by-products of organic matters. Determination of levels of PAHs in the indoor environment is important for assessing human exposure to these chemicals. A new short path thermal desorption (SPTD) gas chromatography/mass spectrometry (GC/MS) method for determining levels of PAHs in indoor air was developed. Thermal desorption (TD) tubes packed with glass beads, Carbopack C, and Carbopack B in sequence, were used for sample collection. Indoor air was sampled using a small portable pump over 7 days at 100 ml/min. Target PAHs were thermally released and introduced into the GC/MS for analysis through the SPTD unit. During tube desorption, PAHs were cold trapped (−20 °C) at the front end of the GC column. Thermal desorption efficiencies were 100% for PAHs with 2 and 3 rings, and 99–97% for PAHs with 4–6 rings. Relative standard deviation (RSD) values among replicate samples spiked at three different levels were around 10–20%. The detection limit of this method was at or below 0.1 μg/m 3 except for naphthalene (0.61 μg/m 3 ), fluorene (0.28 μg/m 3 ) and phenanthrene (0.35 μg/m 3 ). This method was applied to measure PAHs in indoor air in nine residential homes. The levels of PAHs in indoor air found in these nine homes are similar to indoor air values reported by others. [ABSTRACT FROM AUTHOR]

In this study, indoor dust samples were collected from 40 houses in Shiraz; Iran, and analyzed to determine 16 Polycyclic Aromatic Hydrocarbons (PAHs) using Gas chromatography–mass spectrometry (GC-MS). The study participants completed the questionnaires consisting of a series of questions for collecting information about symptoms of sick building syndrome and parameters affecting PAHs concentrations (including traffic congestion in the area, floor level, house renovation, building age, etc.). The total PAHs concentrations in the settled dust samples ranged from 31 to 453 n g g − 1 so that, phenanthrene, naphthalene and fluoranthene were the predominant congeners. Diagnostic ratios and principal component analysis (PCA) indicated the predominance of vehicular (especially diesel vehicle emissions) and cooking emissions, as the two major sources of PAHs, in indoor dust. The results of statistical analysis showed a significant association between the total PAHs concentrations and SBS symptoms (headache, skin dryness, itching, and inflammation). In addition, based on health risk assessment, the mean ILCR (Incremental Lifetime Cancer Risk) value was reported to be 3.85 × 10−5 for adults and 4.36 × 10−5 for children, indicating potential cancer risk as a result of exposure to household dust containing PAHs. The findings of this study can provide useful information to improve the quality of the indoor environment of houses. • The total PAHs concentrations in the dust samples ranged from 31 to 453 n g g − 1 . • Diesel vehicle and cooking emissions were the two major sources of PAHs in dust. • Exposure to PAHs might pose potential cancer risk for adults and children. • There was an association between the concentration of ∑PAHs and some SBS symptoms. [ABSTRACT FROM AUTHOR]

An integrated microsystem for (indoor) air quality monitoring applications is presented. By combining a gas pre-concentrator based on metal-organic frameworks (MOFs) and a metal oxide semiconductor gas sensor, a device for detecting ppb levels of volatile organic compounds was designed, integrated and tested with benzene as a target gas. Two metal organic frameworks have been characterized for their suitability as gas pre-concentration materials for benzene and toluene using inverse gas chromatography and mass spectrometry measurements in order to obtain breakthrough values for gas adsorption. Both MOFs showed a higher pre-concentration effect compared to Tenax ® TA, a state-of-the-art commercial adsorbent material. By depositing a MOF material on a micro hotplate integrated in a package together with a gas sensor, an integrated gas sensor microsystem was realized. This system has been characterized in FEM simulations concerning its gas pre-concentration capabilities and behavior. Test measurements were performed using benzene at concentrations of 10–1000 ppb. Both the simulations and the measurements show the suitability of the system design for the task. Significantly increased gas concentrations have been observed during thermal desorption from the pre-concentrator after gas adsorption at a low temperature. [ABSTRACT FROM AUTHOR]

Very volatile organic compounds ( VVOCs), as categorized by the WHO, are an important subgroup of indoor pollutants and cover a wide spectrum of chemical substances. Some VVOCs are components of products commonly used indoors, some result from chemical reactions and some are reactive precursors of secondary products. Nevertheless, there is still no clear and internationally accepted definition of VVOCs. Current approaches are based on the boiling point, and the saturation vapor pressure or refer to analytical procedures. A significant problem is that many airborne VVOCs cannot be routinely analyzed by the usually applied technique of sampling on Tenax TA® followed by thermal desorption GC/ MS or by DNPH-sampling/ HPLC/ UV. Some VVOCs are therefore often neglected in indoor-related studies. However, VVOCs are of high significance for indoor air quality assessment and there is need for their broader consideration in measurement campaigns and material emission testing. [ABSTRACT FROM AUTHOR]

This study aimed to compare and assess phthalate contamination in various indoor environments. In this study, 44 floor dust samples from different indoor environments in Delaware, USA were collected and analyzed for 14 phthalates using gas chromatography-mass spectrometry. Phthalates were detected in all dust samples with the total concentration ranging from 84 to 7117 mg kg−1. DEHP (di-2-ethylhexyl phthalate), BzBP (benzylbutyl phthalate), DBP (dibutyl phthalate), and DiBP (di-isobutyl phthalate) were both the most frequently and abundantly detected phthalates. The average concentration of total phthalates in dust from offices, student dorms, gyms, stores, and daycare centers was found to be significantly or insignificantly (P= 0.05) higher than that in dust from houses and apartments. Plastic flooring materials and the application of floor care chemical products were positively associated with total phthalate concentration in floor dust. Toxicological risk assessment indicated that an investigated daycare center in this study was the only indoor environment that may cause the intake amount of DEHP of infants, toddlers, and children via dust ingestion to exceed the reference dose established by the U.S. Environmental Protection Agency (USEPA). Regular monitoring on phthalate contamination in sensitive indoor environments is recommended. [ABSTRACT FROM AUTHOR]

A method coupling thermal desorption and gas chromatography/mass spectrometry (GC/MS) was developed for the simultaneous determination of 7 pyrethroids (allethrin, bifenthrin, cyphenothrin, imiprothrin, permethrin, prallethrin and tetramethrin) and piperonyl butoxide adsorbed on Tenax TA ® passive samplers after exposure in indoor air. Thermal desorption was selected as it permits efficient and rapid extraction without solvent used together with a good sensitivity. Detection ( S / N >3) and quantification ( S / N >10) limits varied between 0.001 ng and 2.5 ng and between 0.005 and 10 ng respectively with a reproducibility varied between 14% (bifenthrin) and 39% (permethrin). The method was used for the comparison indoor air contamination after low-pressure spraying and fumigation application in a rubbish chute situated in the basement of a building. [ABSTRACT FROM AUTHOR]

In order to assess indoor air quality (IAQ), two 1-week monitoring campaigns of volatile organic compounds (VOC) were performed in different areas of a multistorey shopping mall. High-spatial-resolution monitoring was conducted at 32 indoor sites located in two storehouses and in different departments of a supermarket. At the same time, VOC concentrations were monitored in the mall and parking lot area as well as outdoors. VOC were sampled at 48-h periods using diffusive samplers suitable for thermal desorption. The samples were then analyzed with gas chromatography-mass spectrometry (GC-MS). The data analysis and chromatic maps indicated that the two storehouses had the highest VOC concentrations consisting principally of terpenes. These higher TVOC concentrations could be a result of the low efficiency of the air exchange and intake systems, as well as the large quantity of articles stored in these small spaces. Instead, inside the supermarket, the food department was the most critical area for VOC concentrations. To identify potential emission sources in this department, a continuous VOC analyzer was used. The findings indicated that the highest total VOC concentrations were present during cleaning activities and that these activities were carried out frequently in the food department. The study highlights the importance of conducting both high-spatial-resolution monitoring and high-temporal-resolution monitoring. The former was able to identify critical issues in environments with a complex emission scenario while the latter was useful in interpreting the dynamics of each emission source. [ABSTRACT FROM AUTHOR]

The aim of this work was to determine the level of benzene, toluene, o -xylene and m, p -xylene (BTX) in air samples collected from the cabins of new and used vehicles of the same model. Ten new vehicles were examined in order to check interior emission from materials used to equip the passenger compartment. In order to compare and define the impact of exhaust gases, air samples were also collected from two used cars, at different mileages (up to 20,000 km). All vehicles tested were of the same type. Samples were collected onto Carbograph 1TD sorbent, thermally desorbed and examined with the use of gas chromatography with flame ionisation and mass spectrometry detectors. All results obtained were referred to Polish and German requirements for indoor air quality (both in public buildings and in workspace environments). Average benzene, toluene, o -xylene and m, p -xylene concentrations in new cars were determined at the level of 11.8 μg/m 3 , 82.7 μg/m 3 , 21.2 μg/m 3 and 89.5 μg/m 3 , respectively. In the used cars, BTX concentration increased with increasing vehicle mileage. The most significant increase of BTX concentration was observed above 11,000 km mileage. [ABSTRACT FROM AUTHOR]

In this work, phthalic acid esters (PAEs): dimethyl phthalate (DMP), diethyl phthalate (DEP), di- n-butyl phthalate, benzyl butyl phthalate, bis(2-ethylhexyl) phthalate, and di- n-octyl phthalate in indoor dust (used as passive sampler) were investigated. The settled dust samples were collected from thirteen indoor environments from Palermo city. A fast and simple method using Soxhlet and GC-MS analysis has been optimized to identify and quantify the phthalates. Total phthalates concentrations in indoor dusts ranged from 269 to 4,831 mg/kg d.w. (d.w. = dry weight). The data show a linear correlation between total PAEs concentration and a single compound content, with the exclusion of the two most volatile components (DMP and DEP) that are present in appreciable amounts only in two samples. These results suggest that most of the PAEs identified in the samples of settled dust originate from the same type of material. This evidence indicates that, in a specific indoor environment, generally is not present only one compound but a mixture having over time comparable percentages of PAEs. Consequently, for routine analyses of a specific indoor environment, only a smaller number of compounds could be determined to value the contamination of that environment. We also note differences in phthalate concentrations between buildings from different construction periods; the total concentration of PAEs was higher in ancient homes compared to those constructed later. This is due to a trend to reduce or remove certain hazardous compounds from building materials and consumer goods. A linear correlation between total PAEs concentration and age of the building was observed ( R = 0.71). [ABSTRACT FROM AUTHOR]

This study investigated the pollution caused by unregulated chemical substances in Korean residential environments. A TA tube was used for indoor air collection, and Gas Chromatography–Mass Spectrometry was used for the analysis of chemical substances. According to the results of this study, 13 substances out of the 16 analyzed chemicals were detected and, among them, the concentrations of phenol, α-pinene, and limonene within the indoor air were high. The average concentration of phenol was 32.7 µg/m3. α-pinene and limonene were detected, of which the highest concentrations were as 598.2 µg/m3 and 652.5 µg/m3, respectively. The maximum concentrations of these three substances exceeded the levels of the lowest concentration of interest. Notably, α-pinene and limonene were released from the wood itself. Wood has been widely used indoors as a natural building material and as furniture. Therefore, it was considered that this was the reason for the high the concentrations of the two substances in indoor air. However, we do not argue that the usage of wood should be reduced because of the results obtained in this study. Instead, we sµggest that it is important to reduce the emissions of α-pinene and limonene throµgh the processing of the wood, extending its drying period, and determining the most appropriate time of use. [ABSTRACT FROM AUTHOR]

In the last decade, the development of novel analytical methodologies enabled the identification of several environmental pollutants responsible for health problems associated with indoor exposure. Polycyclic aromatic hydrocarbons (PAHs) are among the potential hazardous chemicals present in ambient air. Due to their bioaccumulation potential and carcinogenic/mutagenic effects, 16 PAHs are currently listed as priority air pollutants. The main goal of this work was to implement a new and simple method for sampling and determination of PAHs in air by using a thermal desorption (TD) technique followed by gas chromatography coupled with mass spectrometry analysis. A detailed study was carried out to optimise the experimental method in each of its phases, including (active) sampling, TD and chromatographic analysis. The results demonstrate that this approach allowed the detection and quantification of the six more volatile PAHs, namely, naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, and anthracene. Acceptable precision and good linearity over the explored range were obtained. No carry-over was observed during experimental tests and the method provided a reproducible answer. The applicability of the novel methodology was tested in real environment, namely, on the roof of a building in an urban area, in a domestic kitchen and in a collective car garage. The method enabled the identification of two PAHs in the field samples, specifically, naphthalene (two rings) and phenanthrene (three rings). With regard to PAHs sample composition, the most abundant PAH found, in the three different locations, was naphthalene, accounting for about 84-100 % of the total PAH mass detected. [ABSTRACT FROM AUTHOR]

Abstract: Municipal solid waste treatment facilities are generally faced with odorous nuisance problems. Characterizing and determining the odorous charge of indoor air through odour units (OU) is an advantageous approach to evaluate indoor air quality and discomfort. The assessment of the OU can be done through the determination of volatile organic compounds (VOCs) concentrations and the knowledge of their odour thresholds. The evaluation of the presented methodology was done in a mechanical–biological waste treatment plant with a processing capacity of 245.000tonsyear−1 of municipal residues. The sampling was carried out in five indoor selected locations of the plant (Platform of Rotating Biostabilizers, Shipping warehouse, Composting tunnels, Digest centrifugals, and Humid pre-treatment) during the month of July 2011. VOC and volatile sulphur compounds (VSCs) were sampled using multi-sorbent bed (Carbotrap, Carbopack X, Carboxen 569) and Tenax TA tubes, respectively, with SKC AirCheck 2000 pumps. The analysis was performed by automatic thermal desorption (ATD) coupled with a capillary gas chromatography (GC)/mass spectrometry detector (MSD). One hundred and thirty chemical compounds were determined qualitatively in all the studied points (mainly alkanes, aromatic hydrocarbons, alcohols, aldehydes, esters, and terpenes), from which 86 were quantified due to their odorous characteristics as well as their potentiality of having negative health effects. The application of the present methodology in a municipal solid waste treatment facility has proven to be useful in order to determine which type of VOC contribute substantially to the indoor air odorous charge, and thus it can be a helpful method to prevent the generation of these compounds during the treatment process, as well as to find a solution in order to suppress them. [Copyright &y& Elsevier]

Abstract: A novel needle-type sample preparation device was developed for the effective preconcentration of volatile organic compounds (VOCs) in indoor air before gas chromatography–mass spectrometry (GC–MS) analysis. To develop a device for extracting a wide range of VOCs typically found in indoor air, several types of particulate sorbents were tested as the extraction medium in the needle-type extraction device. To determine the content of these VOCs, air samples were collected for 30min with the packed sorbent(s) in the extraction needle, and the extracted VOCs were thermally desorbed in a GC injection port by the direct insertion of the needle. A double-bed sorbent consisting of a needle packed with divinylbenzene and activated carbon particles exhibited excellent extraction and desorption performance and adequate extraction capacity for all the investigated VOCs. The results also clearly demonstrated that the proposed sample preparation method is a more rapid, simpler extraction/desorption technique than traditional sample preparation methods. [Copyright &y& Elsevier]

Abstract: Air in a room infested by Cimex lectularius L. (Hemiptera: Cimicidae) was sampled simultaneously by three different sampling devices including solid phase microextraction (SPME) fiber coatings, thin film microextraction (TFME) devices, and needle trap devices (NTDs) and then analyzed by gas chromatography–mass spectrometry (GC–MS). The main focus of this study was to fully characterize indoor air by identifying compounds extracted by three different microextraction formats and, therefore, perform both the device comparison and more complete characterization of C. lectularius pheromone. The NTD technique was capable of extracting both (E)-2-hexenal and (E)-2-octenal, which were previously identified as alarm pheromones of bedbugs, and superior NTD recoveries for these two components allowed reliable identification based on mass spectral library searching and linear temperature programmed retention index (LTPRI) technique. While the use of DVB/CAR/PDMS SPME fiber coatings provided complementary sample fingerprinting and profiling results, TFME sampling devices provided discriminative extraction coverage toward highly volatile analytes. In addition to two alarm pheromones, relative abundances of all other analytes were recorded for all three devices and aligned across all examined samples, namely, highly infested area, less infested area, and control samples which were characterized by different bedbug populations. The results presented in the current study illustrate comprehensive characterization of infested indoor air samples through the use of three different non-invasive SPME formats and identification of novel components comprising C. lectularius pheromone, therefore, promising future alternatives for use of potential synthetic pheromones for detection of infestations. [Copyright &y& Elsevier]

Abstract: A new methodology has been developed to determine volatile organic compounds (VOCs) and pesticides in ambient air using membrane based devices as passive samplers. Pesticides were determined by gas chromatography with mass spectrometry detection (GC–MS) after their microwave-assisted extraction (MAE) from the passive sampler and the required clean-up. On the other hand, VOCs were also caught with the same samplers and directly determined by head space (HS) coupled to GC–MS. The use of samplers filled with florisil and activated carbon allows us to catch with a simple device both, VOCs and pesticides, with a high vapor pressure. Results obtained in the deployment of samplers in different sites of a phytosanitary plant evidenced the presence of high quantities of chlorpyriphos at thousand ngm3 and also metalaxyl, oxyfluorphen and lindane at ngm3 together with carbon disulfide, 2,2,4-trimethylpentane, ethylbenzene and xylene. [Copyright &y& Elsevier]

Abstract: Due to increasing interest in indoor air quality (IAQ) monitoring for demand controlled ventilation (DCV) aiming at improved perceived air quality, health, energy and cost saving, the objective of this study has been the development of a sensor module based on a single microelectromechanical-system (MEMS) metal oxide semiconductor (MOS) gas sensor for IAQ monitoring as close as possible to the human sensory impression in indoor environments. Based on the results of a statistical evaluation on human induced volatile organic compounds (VOCs) in the ambient air of indoor environments correlating with human presence and perceived air quality, the performance of differently doped SnO2 thick film gas sensor materials has been investigated in laboratory and by means of field tests in order to find the most promising sensor material for IAQ monitoring based on the detection of changes of human induced VOCs in indoor air. Implementation of an empirical evaluation algorithm reversing proportionality of anthropogenic CO2 production and other bio-effluent generation allows prediction of CO2 equivalent units. Analytical instrumentation and reference sensors served to evaluate the effectiveness of the developed sensor module in real-life. [Copyright &y& Elsevier]

Abstract: The technique of thermal desorption (TD)-GC/MS was evaluated for the measurement of monoterpenes in indoor air. The validation strategy was intentionally oriented towards routine use and the reliability of the method rather than extreme performance. For this reason, validation by accuracy profile was chosen. The accuracy profile procedure, which is based on the concept of total error (bias+standard deviation), guarantees that a known proportion of future results obtained with the method will be within acceptance limits. For all the compounds tested in the present study, α-pinene, α-terpineol, β-pinene, d-limonene, Δ3-carene, camphene, 1,8-cineole, p-cymene, linalool, but not in the case of carvone, the accuracy profile procedure established that at least 95% of the future results obtained would be within the ±15% acceptance limits of the validated method over the whole defined concentration range. Other parameters, such as selectivity, recovery, repeatability, stability of the molecules of interest and the effect of temperature, were also determined. The performance of the described method was finally evaluated by the analysis of indoor air from new timber frame constructions. [ABSTRACT FROM AUTHOR]

The hydroxyl radical (OH) plays a key role in determining indoor air quality. However, its highly reactive nature and low concentration indoors impede direct analysis. This paper describes the techniques used to indirectly quantify indoor OH, including the development of a new method based on the instantaneous release of chemical tracers into the air. This method was used to detect ambient OH in two indoor seminar rooms following tracer detection by gas chromatography-mass spectrometry (GCMS). The results from these tests add to the small number of experiments that have measured indoor OH which are discussed with regard to future directions within air quality research. [ABSTRACT FROM AUTHOR]

Abstract: Exposure to fragrance substances is exponentially increasing in our daily life due to the enhanced use of scented products. Some fragrances are known to be important sensitizers, inhalation being an important exposure pathway in indoor environments. A simple and sensitive method based on solid-phase enrichment and solid-phase microextraction (SPME) followed by gas chromatography–mass spectrometry (GC–MS) has been developed for the analysis of 24 volatile fragrance allergens in indoor air. Suspected allergens present in the air (0.2m3) were adsorbed onto a very small quantity of florisil (25mg) and then transferred to a SPME fiber in the headspace mode (HS). To the best of our knowledge, this paper describes the first application of SPME for the determination of these compounds in air samples. The experimental parameters affecting the microextraction process have been optimized using a multifactor experimental design strategy. Accuracy, linearity, precision and detection limits (LODs) were evaluated to assess the performance of the proposed method. External calibration, using spiked sorbent standards, and not requiring the complete sampling process (only the SPME step), demonstrated to be suitable for the quantification of all suspected allergens. Recovery studies were performed at three concentration levels (0.04, 1.00 and 50μgm−3), obtaining quantitative recoveries (≥85%) in most cases. LOD values at the low ngm−3 level were achieved for all the target compounds. The application of the method to daily home air samples demonstrated the ubiquity of this kind of fragrance ingredients in quotidian indoor environments, finding 18 of the 24 considered compounds in concentrations ranging from 0.01 to 56μgm−3. Benzyl alcohol, linalool, citronellol, ionone and lilial were found in most analyzed samples. [Copyright &y& Elsevier]

Abstract: Tobacco-specific nitrosamines (TSNAs) are some of the most potent carcinogens in tobacco and cigarette smoke. Accurate quantification of these chemicals is needed to help assess public health risks. We developed and validated a specific and sensitive method to measure four TSNAs adsorbed to model surfaces and secondhand smoke (SHS) particles using gas chromatography–ion-trap tandem mass spectrometry. In an 18-m3 room-sized chamber, a smoking machine generated realistic concentrations of SHS that were actively sampled on Teflon-coated fiber glass (TCFG) filters, and passively sampled on cellulose substrates. A simple solid–liquid extraction protocol using methanol as solvent was successfully applied to both substrates with recoveries ranging from 85 to 115%. For each TSNA, tandem MS parameters were optimized and the major fragmentation pathways were elucidated. The method showed excellent performance, with a linear dynamic range from 2 to 1000ngmL−1, low detection limits (S/N>3) of 30–300pgmL−1 and precision with experimental errors below 10% for all compounds. Moreover, no interfering peaks were observed, indicating a high selectivity of MS/MS without the need for a sample clean-up step. This method provides a suitable analytical tool to detect and quantify traces of TSNA in indoor environments polluted with SHS. [Copyright &y& Elsevier]

Abstract: An experimental project was conducted to investigate mold products, namely spores and volatile organic compounds (VOCs) in the cavity of full-scale stud wall assemblies. Twenty specimens were constructed and tested to inquire the capacity of wall cavities to restrain mold products, emanating from studs with 10% of their surface covered with mold, from penetrating into the indoor space. The tests were designed primarily to study the movement of spores. The project was subsequently extended to investigate the identification of microbial volatile organic compounds (MVOCs) and their transport through the building envelope. This paper presents the experimental design, testing procedure and a summary of the analysis conducted to identify mold related VOCs and their transport from the cavity to the indoor space, and the evaluation of the influence of experimental factors on this transport. Six experimental factors were investigated: air leakage path; mold presence; wall construction configurations (insulation, vapor barrier and sheathing material) and ambient conditions (dry and wet conditions). The chemical analysis of VOCs (volatile organic compounds) was performed using gas chromatography/mass spectrometry (GC/MS). Results are analyzed using multiple regression analysis to identify the mold related VOCs, and to determine the transport through the building envelope. Five VOCs are confirmed to be related to the mold presence in the cavity and the transport of these MVOCs is supported by the data. However, no significant effect of the construction factors on MVOC transport is detected. [Copyright &y& Elsevier]

Concerns about indoor air quality and the potential effects on people living in these environments are increasing as more reports about the toxicities and the potential indoor air exposure levels of household-use chemicals and chemicals from housing and furnishing manufacture in air are being assessed. Gas chromatography/mass spectrometry was used to confirm numerous airborne contaminants obtained from the analysis of semipermeable membrane devices deployed inside of 52 homes situated along the border between Arizona and Mexico. We also describe nontarget analytes in the organochlorine pesticide fractions of 12 of these homes; this fraction is also the most likely to contain the broadest scope of bioconcentratable chemicals accumulated from the indoor air. Approximately 400 individual components were identified, ranging from pesticides to a wide array of hydrocarbons, fragrances such as the musk xylenes, flavors relating to spices, aldehydes, alcohols, esters and phthalate esters, and other miscellaneous types of chemicals. The results presented in this study demonstrate unequivocally that the mixture of airborne chemicals present indoors is far more complex than previously demonstrated. [ABSTRACT FROM AUTHOR]

The level of carbonyl compounds in indoor air is crucial due to possible health effects and the high prevalence of their potential sources. Therefore, selecting a convenient and rapid analytical technique for the reliable detection of carbonyl compound concentrations is important. The acetyl acetone (acac) method is a widely used standard procedure for detecting gaseous formaldehyde. For measuring formaldehyde along with other carbonyl compounds, the DNPH-method is commonly applied. The recommended procedure for measuring volatile organic compounds (VOCs) is sampling on Tenax TA, followed by thermal desorption and GC/MS analysis. In this study, different analytical techniques for the quantification of formaldehyde, pentanal, and hexanal are critically compared. It was found that the acac- and DNPH-method are in very good agreement for formaldehyde. In contrast, the DNPH-method significantly underestimates indoor air concentrations of the higher aldehydes in comparison to sampling on Tenax TA, although both methods are strongly correlated. The reported results are part of the EURIMA-WKI study on levels of indoor air pollutants resulting from construction, building materials and interior decoration. [Copyright &y& Elsevier]

The article presents a study on the aromatic and aliphatic hydrocarbons in the indoor air. The study utilizes air samples taken from SKC Inc. and employs Hewlett-Packard 5988A gas chromatography/mass spectrometry (GC-MS) system for the analysis of mixtures and samples. The study reveals that volatile polycyclic aromatic hydrocarbon compounds found in the air include fluorine, anthracene, and acenaphthene.

A large quantity of oily fumes is generated in fast food and Chineserestaurants from cooking oil kept at a high temperature in the kitchens. If these oily fumes are not properly abated, they can be a majorsource of organic emissions in some dense urban areas with a lot of restaurants such as found in Hong Kong. In the present study, the most commonly used cooking oil, peanut oil, was kept at 260 deg. C in anenvironment typical of a commercial kitchen that consisted of a two-burner stir-frying cooking range, a single-tank electric fryer, a baffle-type grease extractor and an exhaust duct. Air samples were collected at the inlet of the grease extractor and the exit of the exhaustduct. Organic material was extracted from these samples and examinedby gas chromatography and gas chromatography/mass spectrometry. A new extraction protocol using a Soxhlet apparatus and freshly distilledchloroform as the solvent was established in this study. It was noticed that there was no appreciable breakdown of the oil composition atthe temperature studied. The efficiency of the grease extractor was determined by obtaining the relative concentrations of gas phase organic composites at the sampling positions. [ABSTRACT FROM AUTHOR]