Total Volatile Organic Compounds Levels Research Articles

The Formaldehyde, TVOCs, PM2.5 and PM10 Concentrations at Outdoor Street Food in Kalasin, Thailand

Human health and well-being are directly impacted by air quality. Cardiovascular and respiratory problems have been linked to exposure to pollutants such as formaldehyde, total volatile organic compounds (TVOCs), and particulate matter 2.5 and 10 micrometers (PM2.5 and PM10). This study aimed to quantify formaldehyde, TVOCs, PM2.5, and PM10 levels in the outdoor air at street food vendors in Kalasin, Thailand. The study was conducted at street food vendors in the province of Kalasin. Formaldehyde values at the top five food stalls in Kalasin ranged from 0.58 to 1.41 mg/m3. The PM2.5 values ranged from 2.29 to 9.43 ug/m3, and the TVOC values ranged from 2.91 to 7.02 ug/m3, with PM10 concentrations ranging from 2.86 to 7.29 ug/m3. Drawing on data about these pollutant concentrations across five distinct locations, the following recommendations can be put forth: Elevated levels of formaldehyde, TVOCs, PM2.5, and PM10 in certain areas can have detrimental effects on the environment and human well-being.

Indoor air pollutants and microbes in mass rapid transit (MRT) trains of north-western area of Bangkok, Thailand: Impact on indoor air quality and human health

Most modern cities suffer from urban air pollution caused by human activity such as traffic and other sources. Various pollutants in the environment may pose a threat to the health of commuters. The objective of this study is to assess the indoor air quality (IAQ) in MRT purple line trains serving the north-western area of Bangkok in order to determine any potential impacts on human health. The monitored parameters include total volatile organic compounds (TVOCs), temperature, relative humidity, carbon monoxide (CO), carbon dioxide (CO2), ozone (O3), formaldehyde (CH2O), and fine particulate matter (PM2.5). The indoor air pollutant concentrations in the MRT remained within the permissible thresholds. The results of the correlation analysis reveal that relative humidity (RH) and PM2.5 are positively correlated in both the wintertime and summertime measurement campaigns. In contrast, CO2 correlated with temperature in the wintertime and CO in the rainy season. Bacterial and fungal loads were estimated during various measurement campaigns in MRT. Fungi and bacterial loads were higher in the MRT trains during the wintertime and rainy season campaigns. The IAQ of MRT train in Bangkok is within the satisfactory and excellent category of air quality index (AQI). The inhaled doses of PM2.5, CO, and VOCs were also estimated to identify their health effects on commuters. The inhaled dose of PM2.5 was comparatively higher than other pollutants. In this study, a general perspective of the IAQ in the MRT system was provided. It is recommended to conduct more research studies on various MRT lines in Bangkok to further investigate the levels of bacteria, fungi, TVOCs, O3, and PM. Additionally, the ventilation mode in MRT needs to be investigated as it is the main factor affecting the IAQ.

Emission of volatile organic compounds during open fire cooking with wood biomass: Traditional three-stone open fire vs. gasifier cooking stove in rural Kenya

Cooking with wood biomass fuels releases hazardous air pollutants, including volatile organic compounds (VOCs), that often disproportionally affect women and children. This study, conducted in Kwale and Siaya counties in Kenya, employed thermal desorption gas chromatography – mass spectrometry to analyse VOC emissions from cooking with a wood biomass three-stone open fire vs. top-lit updraft gasifier stove. In kitchens with adequate ventilation, total VOC levels increased from 35–252 μg∙m−3 before cooking to 2235–5371 μg∙m−3 during open fire cooking, whereas use of a gasifier stove resulted in reduced emissions from cooking by 48–77 % (506–2778 μg∙m−3). However, in kitchens with poor ventilation, there was only a moderate difference in total VOC levels between the two methods of cooking (9034–9378 μg∙m−3 vs. 6727–8201 μg∙m−3 for the three-stone open fire vs. gasifier stove, respectively). Using a non-target screening approach revealed significantly increased levels of VOCs, particularly benzenoids, oxygenated and heterocyclic compounds, when cooking with the traditional open fire, especially in closed kitchens, highlighting the effects of poor ventilation. Key hazardous VOCs included benzene, naphthalene, phenols and furans, suggesting potential health risks from cooking. In kitchens with good ventilation, use of the gasifier stove markedly reduced emissions of these priority toxic VOCs compared to cooking with an open fire. Thus, substituting open fires with gasifier stoves could help to improve household air quality and alleviate health risks. The study revealed that VOCs were present prior to cooking, possibly originating from previously cooked food (buildup) or the outside environment. VOC emissions were also exacerbated by reduced air flow in high humidity during rainfall, suggesting an area for further research. The findings underscore the importance of adopting cleaner cooking technologies and enhancing kitchen ventilation to mitigate the impacts of VOCs in developing countries.

Assessment of indoor and outdoor formaldehyde, total volatile organic compounds (TVOC), and particulate matter (PM2.5, and PM10) levels in Kalasin, Thailand

Background This study sought to determine how much formaldehyde, TVOCs (total volatile organic compounds), and particulate matter (PM2.5, and PM10) were present in the air inside and outdoors at seven distinct locations in Kalasin Province. Methods The stations that were chosen comprised roadways of importance, neighborhoods where people live, shopping centers, motorcycle repair shops, gas stations, industrial zones, and rural areas. A gas detector with four sensors was used to measure formaldehyde, PM2.5, TVOC, temperature, and humidity levels. Particulate samplers were used specifically for measuring PM2.5 and PM10 concentrations. The formaldehyde and TVOC sensors were utilized to measure the concentrations of specific air contaminants. Results These stations from important roads, residential neighborhoods, shopping centers, motorcycle repair shops, gas stations, industrial zones, and rural locations had formaldehyde of 0.0207, 0.0239, 0.1892, 0.1893, 0.0273, 0.0262, and 0.0409 mg/m3, respectively. It was discovered that TVOC values ranged from 0.0848 to 0.990 to 0.8466 to 0.1944 to 0.1188 to 0.108 to 0.1708 mg/m3. The measurements for PM 2.5 were 4.7778, 4.2222, 5.0000, 3.4444, 4.7778, 5.7778, and 6.6667 μg/m3 at the roads, residential neighborhoods, shopping centers, motorcycle repair shops, gas stations, industrial zones, and rural locations. The measurements for PM10 were 4.7778, 4.0000, 5.0000, 3.1111, 5.0000, 6.0000, and 8.0000 μg/m3, respectively. According to the research, formaldehyde levels in stores and motorbike maintenance facilities are higher than the Thai Air Standard. The only TVOC concentration that was found to be above the allowable limit was in shopping centers. However, despite the rural area station showing slightly increased levels, all stations met the PM2.5 and PM10 air quality criteria. Conclusions People who breathe polluted air face both short- and long-term health concerns, underscoring the significance of spreading awareness of this problem.

Origin and transformation of volatile organic compounds at a regional background site in Hong Kong: Varied photochemical processes from different source regions

Volatile organic compounds (VOCs) are important gaseous constituents in the troposphere, impacting local and regional air quality, human health, and climate. Oxidation of VOCs, with the participation of nitrogen oxides (NOx), leads to the formation of tropospheric ozone (O3). Accurately apportioning the emission sources and transformation processes of ambient VOCs, and effectively estimation of OH reactivity and ozone formation potential (OFP) will play an important role in reducing O3 pollution in the atmosphere and improving public health. In this study, field measurements were conducted at a regional background site (Hok Tsui; HT) in Hong Kong from October to November 2020 with proton-transfer-reaction time-of-flight mass spectrometry (PTR-ToF-MS). VOC data coupled with air mass back trajectory cluster analysis and receptor modelling were applied to reveal the pollution pattern, emission sources and transformation of ambient VOCs at HT in autumn 2020. Seven sources were identified by positive matrix factorization (PMF) analysis, namely vehicular + industrial, solvent usage, primary oxygenated VOCs (OVOCs), secondary OVOCs 1, secondary OVOCs 2 (aged), biogenic emissions, and background + biomass burning. Secondary formation and vehicular + industrial emissions are the vital sources of ambient VOCs at HT supersite, contributing to 20.8 % and 46.7 % of total VOC mixing ratios, respectively. Integrated with backward trajectory analysis and correlations of VOCs with their oxidation products, short-range transport of air masses from inland regions of southeast China brought high levels of total VOCs but longer-range transport of air masses brought more secondary OVOCs in aged air masses. Photolysis of OVOCs was the most important contributor to OH reactivity and OFP, among which aldehyde was the dominant contributor. The results of this study highlight the photochemical processing of VOCs from different source regions which should be considered in strategy making for pollution reduction.

Assessment of indoor air quality in air-conditioned small business units with no mechanical ventilation

Shophouses, a common building type in Singapore, host small business units typically cooled by non-mechanically ventilated strategies. Activities in these spaces include cooking food and handling nail and hair products, which emit volatile organic compounds (VOCs), carbon monoxide (CO), and other airborne contaminants that could compromise indoor air quality (IAQ). This study assessed potential IAQ risk by quantifying total VOCs (TVOC), formaldehyde, carbon dioxide (CO2), and CO levels in 100 air-conditioned small business units in Singapore's shophouses. The median (maximum) concentrations across all units were TVOC:179 (54,880 ppb), formaldehyde:0 (1.0 ppm), CO2:586 (2750 ppm) and CO:0 (0.5 ppm). The majority (90%) of the units did not have mechanical ventilation provision, and TVOC and formaldehyde levels correlated significantly with corresponding CO2 levels (p ≤ 0.05). The highest levels of TVOC and formaldehyde were measured at nail salons (TVOC: 54,880 ppb, formaldehyde: 1.0 ppm). Improving ventilation combined with use of alternative low-emission products could improve IAQ in small business units.

Is indoor environment a risk factor of building-related symptoms?

The indoor environment, particularly indoor air quality (IAQ), is significantly associated with building-related symptoms (BRSs) in humans. In our previous studies, we demonstrated a significant relationship between BRSs and indoor chemical concentrations. In Japan, the Ministry of Health, Labor, and Welfare (MHLW) guideline recommends an air quality target of 13 volatile organic compounds (VOCs) and a provisional target of 400 μg/m3 for total VOCs (TVOC). The objective of this study was to determine the relationship between TVOC levels and the risk of BRSs using the Japanese provisional target TVOC level of 400 μg/m3. The relationship between odor intensity and BRSs while the TVOC levels were under 400 μg/m3 was also examined. The study was conducted in a laboratory house (LH) on the campus of Chiba University from 2017-2019. The study included 149 participants who spent 60 minutes in the LH. The participants were asked to evaluate the IAQ of the LH. A significant relationship between the risk of BRSs and the provisional target TVOC level was observed (odds ratio: 2.94, 95% confidence interval: 1.18-7.35). Furthermore, a significant relationship between odor intensity and risk of BRSs in spaces with TVOC levels less than 400 μg/m3 was detected (odds ratio: 6.06, 95% confidence interval: 1.21-30.44). In conclusion, the risk of BRSs is significantly lower in spaces with low TVOC levels and low odor intensity. Reducing the concentration of airborne chemicals and odor intensity may improve IAQ and prevent BRSs.

Indoor exposure assessment for levels of dust mite and total volatile organic compounds (TVOCs) in living houses

ABSTRACT The purpose of this study is to measure the levels of dust mites (Dermatophagoides farina group 1 [Der f1] and Dermatophagoides pteronyssinus group 1 [Der p1]) and total volatile organic compounds (TVOCs) in the resident environments with living conditions such as the number of ventilation; the number of window, floor, and temperature; and relative humidity (RH) from vulnerable class in South Korea. Information on residents is designed to be prepared by residents on their general characteristics (daily residence time, heating and cooking type, and cleaning on the day of sampling). Dust mites levels ranged from 24.0 to 1087.5 ng/g with a mean of 215.4 ng/g for Der f1 and from 0.6 to 489.9 ng/g with a mean of 489.9 ng/g for Der p1. Total TVOC levels ranged from 15.3 to 1642.1 μg/m3 with a mean of 219.7 μg/m3. The correlation analysis showed a positive association between Der f1 levels and xylene levels in fall (r = 0.49, r < 0.05) of this study.

Analysis of Spatial-Temporal Variation in Floral Volatiles Emitted from Lagerstroemia caudata by Headspace Solid-Phase Microextraction and GC-MS.

Lagerstroemia caudata is a rare aromatic species native to southeastern China, but its floral scent properties and release dynamics remain unclear. This study is the first systematic analysis of spatial-temporal variation in volatile organic compounds (VOCs) emitted from L. caudata by headspace solid-phase microextraction (HS-SPME) with gas chromatography-mass spectrometry (GC-MS). Thirty-two VOCs were identified, 20 of which were detected for the first time. Aldehydes, alcohols, and monoterpenoids were the main VOC categories, each with different releasing rhythms. Total emission of VOCs was much higher in the full-blooming stage (140.90 ng g-1min-1) than in the pre-blooming (36.54 ng g-1min-1) or over-blooming (24.92 ng g-1min-1). Monoterpenoids, especially nerol, geraniol, and linalool, were the characteristic VOCs for full-blooming flowers. Daily emissions of nine compounds (nerol, geraniol, linalool, citronellol, β-citral, (E)-citral, phenylethyl alcohol, 2-heptanol, 2-nonanol) correlated closely with the opening of L. caudata, presenting an apparent diurnal pattern of scent emission. Tissue-specific emission was found in most isolated floral parts. Stamen was the most significant source of floral VOCs, considering its high emission levels of total VOC (627.96 ng g-1min-1). Our results extend the information on floral VOCs of Lagerstroemia and provide a theoretical basis for breeding new cultivars with desirable floral scents.

Sex-differences in the effects of indoor air pollutants and household environment on preschool child cognitive development

Air pollution, outdoor residential environment, indoor household characteristics, and parental mental health are potential factors associated with child development. However, few studies have simultaneously analyzed the association between the aforementioned factors and preschool child (aged 2–5 years) development. This study investigated the effects of those factors on child development and their potential modifying effects. A total of 142 participants were recruited from a birth cohort study in the Greater Taipei Area, and the evaluation was conducted at each participant's home from 2017 to 2020. Child cognitive development was assessed by psychologists using the Bayley Scales of Infant and Toddler Development and the Wechsler Preschool & Primary Scale of Intelligence. Household air pollutants, outdoor residential environment, indoor household characteristics, parental mental health, and other covariates were evaluated. Multiple regressions were used to examine the relationships between child development and covariates. Stratified analysis by child sex and parental mental health was conducted. Average indoor air pollutant levels were below Taiwan's Indoor Air Quality Standards. After adjustment for covariates, the indoor total volatile organic compounds (TVOCs) level was significantly associated with poor child development (per interquartile range increase in the TVOC level was associated with a 5.1 percentile decrease in child cognitive development). Sex difference was observed for the association between TVOC exposure and child development. Living near schools, burning incense at home, purchasing new furniture, and parental anxiety were related to child development. Indoor TVOC level was associated with poor child cognitive development, specifically with the girls. Indoor and outdoor residential environment and parental anxiety interfered with child development. TVOCs should be used cautiously at home to minimize child exposure. A low-pollution living environment should be provided to ensure children's healthy development.

Evaluation of the Effectiveness of Common Indoor Plants in Improving the Indoor Air Quality of Studio Apartments

People spend most of their time indoors, and prolonged exposure to pollution can harm their health. The degradation of indoor air quality (IAQ) has raised serious issues. Botanical biofilters are an exciting solution for lowering indoor air pollution. However, plants cultivated inside under low light intensity (10–50 μmole PAR m−2 s−1) generate CO2 in the indoor atmosphere. Combining C3 (Calvin Cycle) and Crassulacean Acid metabolism (CAM) plants may be able to address this problem by lowering CO2 emission levels and enhancing the efficiency of pollution removal by removing the primary indoor air pollutants from actual interior settings, including carbon dioxide (CO2), formaldehyde (HCHO), particulate matter (PM2.5 and PM10), and total volatile organic compounds (TVOCs). As a result, a successful botanical biofilter made of several plants was researched. Indoor plants can phytoremediate a variety of indoor contaminants. However, just a few studies have demonstrated its efficacy in practical contexts. Due to the harsh winter, apartments in South Korea are frequently closed, necessitating the measurement of interior air pollution concentration in real-time. Four apartments (APT I through APT IV) with various ventilation and indoor plant setups were selected for this investigation. Various combinations of indoor environments (ventilation, low light) and a combination of C3 and CAM indoor plants as a botanical biofilter were used to study the sites over two months. Current research indicates that combining a botanical biofilter with ventilation can reduce levels of CO2, TVOCs, HCHO, PM2.5, and PM10 by 76%, 87%, 75%, 52%, and 51%, respectively. The current study concluded that different indoor potted plants provide an effective, affordable, self-regulating, sustainable option for enhancing indoor air quality and, consequently, human well-being and productivity in small, cramped places.

Thermal performance and indoor air quality in new, medium density houses – Auckland, New Zealand

PurposeNew Zealand’s historical housing stock comprises largely single-storey detached houses, characterised by poor winter comfort with high air infiltration. Challenges with affordability and land use are shifting New Zealand’s housing stock towards double-storey, conjoined medium-density housing (MDH). Reduced external surfaces in this typology should reduce winter heat loss and infiltration, improving winter comfort and health. New concerns arise, however, regarding summertime overheating and poor indoor air quality.Design/methodology/approachA field study was undertaken where temperature, humidity, airtightness, particulate matter (PM) and total volatile organic compounds (TVOC) were measured in two unoccupied, newly built double-storey, conjoined houses, for several weeks over summer.FindingsThe reduced surface area of this typology did not reduce infiltration and demonstrated significant periods of overheating. Internal PM concentrations generally exceeded outdoor concentrations but did not exceed annual average outdoor PM10 guidelines of 20 µg m-3. Infiltration factors (Finf) were closer to more traditional houses. TVOC readings varied widely, but frequently exceeded international guidelines.Research limitations/implicationsThe small sample limits the applications of conclusions more widely. Recommendations to investigate a wider sample in different locations with more detailed VOC analysis over all seasons are made.Practical implicationsImprovements to internal environments cannot be guaranteed by housing typology changes alone and must still involve thoughtful environmental design.Social implicationsHousing typology changes may not improve internal living environments.Originality/valueA move to the new MDH typology may not achieve expectations of airtightness and thermal improvement. New challenges arise from significant overheating and high TVOC levels, which may lead to new negative health effects.

Association between maternal exposure to indoor air pollution and offspring congenital heart disease: a case\u2013control study in East China

BackgroundPrevious research suggested an association between maternal exposure to ambient air pollutants and the risk of congenital heart disease (CHD). However, the effect of individual prenatal exposure to indoor air pollutants on CHD occurrence was not reported.MethodsWe performed a hospital-based case–control study to investigate the association between personal air pollution exposure during pregnancy and the risk of CHD in offspring. A total of 44 cases and 75 controls were included from two hospitals in East China. We investigated maternal and residential environmental characteristics using a questionnaire and obtained personal indoor air samples to assess particulate matter (PM) and volatile organic compounds (VOCs) from 22–30 gestational weeks. Formaldehyde, benzene, toluene, xylene, total volatile organic compounds (TVOCs), PM2.5, and PM10 were assessed. Logistic regression was performed to assess associations and interactions between individual indoor air pollutants and CHD after adjusting for confounders. The potential residential environmental factors affecting the risks of indoor air pollutants on CHD were also assessed.ResultsMedian TVOC (0.400 vs. 0.005 mg/m3, P < 0.001) exposure levels in cases were significantly higher than controls. A logistic regression model adjusted for confounders revealed that exposure to high levels of indoor TVOCs (AOR 7.09, 95% CI 2.10–23.88) during pregnancy was associated with risks for CHD and the occurrence of some major CHD subtype in offspring. These risk effects were enhanced in pregnant women living in a newly renovated house but were mitigated by household use of smoke ventilators when cooking. We observed a positive interaction of maternal exposure to TVOCs and PM2.5 and the risk for CHD.ConclusionsMaternal exposure to indoor VOCs and PMs may increase the risk of giving birth to foetuses with CHD.

Indoor air quality in wards of dental school clinic: Variations of VOCs, CO2 and airborne particle levels

Introduction: The indoor environment of dental clinics may endanger dental patients and personnel and due to a great variety of air pollutants throughout the usual dental operation. The purpose of the present cross-sectional study was the evaluation of Indoor Air Quality (IAQ) and factors affecting it in a dentistry faculty of Arak University of Medical Sciences. Material and methods: The IAQ of five dental active wards and the patient waiting room was evaluated. The concentrations of Total Volatile Organic Compounds (TVOC), CO2, particulate matter, and bioaerosols were measured. Results: The TVOCs concentration in sampling locations ranged between 817 to 3670 μg/m3 during dental work and exceeded the Leadership in Energy and Environmental Design (LEED) guideline in all sampling locations. The highest values of Particulate Matter (PM) for PM10, PM2.5, and PM1 were observed in the periodontics ward, while the lowest values were observed in the endodontics ward. The PM2.5 concentrations exceeded the WHO limit in periodontics and pediatric wards. TVOC levels had a significant positive correlation with temperature (r=0.374, p&lt;0.01) and RH (r=0.265, p&lt;0.05). The predominant bacterial genus of the patient waiting area was Bacillus (36%), while the dominant bacterial genus of the other sampling site was Micrococcus spp. Penicillium (35.5%) and Cladosporium (28%) were the predominant fungi detected. Conclusion: Controlling of airborne particles is to be standardized by the infection control actions of dental clinics and improved ventilation capacity in the air conditioning system was suggested for reducing VOCs and PM concentrations.

Evolution of volatile compounds composition during grape berry development at the germplasm level

Volatile organic compounds (VOCs) are typically important factors in fleshy fruit crop quality. However, qualitative, and quantitative changes of VOCs profiles during grape berry development between different germplasms are not well understood. We surveyed VOCs composition and concentration at three berry development stages (fruit-set, veraison and maturation) in sixty-two grape accessions, and analyzed the relationship between monoterpenes contents and TERPENE SYNTHASE (TPS) genes expression. We identified ninety-four VOCs and observed different patterns of VOCs production through development among the different accessions. Total VOCs levels and the abundance of aldehydes, the most abundant VOCs at all three developmental stages, increased during berry development. Monoterpenes, hydrocarbons, and ketones levels peaked at maturation stage, while alcohols, sesquiterpenes and C13-noisoprenes had the highest concentrations at fruit-set. Correlation analysis indicated that several genes annotated as TPS contribute to monoterpene biosynthesis. These results have promoted the study of VOCs production in grape.

Comprehensive Air Quality Assessment of the Tobacco Heating System 2.2 under Simulated Indoor Environments

Despite the growing popularity of heated tobacco products, there are few comprehensive studies on their environmental aerosols. Therefore, the impact of the Tobacco Heating System 2.2 (THS 2.2) on indoor air quality was evaluated on the basis of a comprehensive list of 31 airborne constituents along with targeted screening of the gas–vapor and particulate phases of the environmental aerosol. The assessments were conducted at three ventilation rates. Indoor use of THS 2.2 increased the levels of nicotine, acetaldehyde, glycerin, and (if mentholated products were used) menthol relative to background levels, with a corresponding increase in total volatile organic compounds (TVOC) values. Moreover, a temporary increase in ultrafine particles was observed when two or more tobacco sticks were used simultaneously or with a short time lapse between usages, but the concentrations returned to close to background levels almost immediately. This is because THS 2.2 generates an aerosol of liquid droplets, which evaporate quickly. Nicotine, acetaldehyde, glycerin, and TVOC levels were measured in the low μg/m3 range and were below the existing guideline limits. A comparison of airborne constituent levels during indoor THS 2.2 use with emissions from combustion products and common everyday activities revealed a substantially lower impact of THS 2.2 on the indoor environment.

Air pollutant emissions from multi jet fusion, material-jetting, and digital light synthesis commercial 3D printers in a service bureau

As additive manufacturing becomes more prevalent in industrial manufacturing facilities, so does human interaction with these machines. In this study, we characterized the size-resolved concentrations of particulate matter (PM, from ≈ 11 to 20,000 nm in size) and volatile organic compounds (VOC) resulting from a material-jetting (Projet 5500X), multi jet fusion (HP MJF 4200), and photopolymerization (Carbon 3D continuous liquid interface production). During all processes, PM concentrations were below the OSHA limits and ultrafine PM (PM0.1) concentrations were well below levels commonly observed for fused deposition modeling printers. PM and total volatile organic compound (VOC) concentrations during printing were close to background levels for the HP MJF printer and HP MJF post processing station. However, the mean particle size of the powder used (PA 12) was above the upper detection limit of the instrument (20 μm). Carbon 3D total VOC levels were highest during part post processing. Cyclic PM emissions from the Projet 5500X printer suggested higher PM emissions during cooling fan activity. VOC analysis revealed high concentrations of HP ink solvents (2-Pyrrolidinone and Triethylene glycol), potential exposure to fluorinated compounds and photoresin VOCs during Carbon 3D post-processing, and exposure to photo-resin compounds during Projet 5500X printing. This study indicates that proper exhaust and facility air exchange can limit concentrations of PM and VOCs and therefore particular attention to the building design and ventilation system should be taken into consideration for additive manufacturing facilities to mitigate potential human exposure and associated health risks.

Wood emissions and asthma development: Results from an experimental mouse model and a prospective cohort study

BackgroundIncreased use of renewable resources like sustainably produced wood in construction or for all sorts of long-lived products is considered to contribute to reducing society's carbon footprint. However, as a natural, biological material, wood and wood products emit specific volatile organic compounds (VOCs). Therefore, the evaluation of possible health effects due to wood emissions is of major interest. ObjectivesWe investigated the effects of an exposure to multiple wood-related VOCs on asthma development. MethodsA murine asthma model was used to evaluate possible allergic and inflammatory effects on the lung after short- or long-term and perinatal exposure to pinewood or oriented strand board (OSB). In addition, wood-related VOCs were measured within the German prospective mother–child cohort LINA and their joint effect on early wheezing or asthma development in children until the age of 10 was estimated by Bayesian kernel machine regression (BKMR) stratifying also for family history of atopy (FHA). ResultsOur experimental data show that neither pinewood nor OSB emissions even at high total VOC levels and a long-lasting exposure period induce significant inflammatory or asthma-promoting effects in sensitized or non-sensitized mice. Moreover, an exposure during the vulnerable time window around birth was also without effect. Consistently, in our mother–child cohort LINA, an exposure to multiple wood-related VOCs during pregnancy or the first year of life was not associated with early wheezing or asthma development in children independent from their FHA. ConclusionOur findings indicate that emissions from wood and wood products at levels commonly occurring in the living environment do not exert adverse effects concerning wheezing or asthma development.

Effect of Increased Cabin Recirculation Airflow Fraction on Relative Humidity, CO2 and TVOC

In the CleanSky 2 ComAir study, subject tests were conducted in the Fraunhofer Flight Test Facility cabin mock-up. This mock-up consists of the front section of a former in-service A310 hosting up to 80 passengers. In 12 sessions the outdoor/recirculation airflow ratio was altered from today’s typically applied fractions to up to 88% recirculation fraction. This leads to increased relative humidity, carbon dioxide (CO2) and Total Volatile Organic Compounds (TVOC) levels in the cabin air, as the emissions by passengers become less diluted by outdoor, dry air. This paper describes the measured increase of relative humidity, CO2 and TVOC level in the cabin air for the different test conditions.

Effect of increased cabin recirculation airflow fraction on relative humidity, CO2 and TVOC

In the CleanSky 2 ComAir study, subject tests were conducted in the Fraunhofer Flight Test Facility cabin mock-up. This mock-up consists of the front section of a former in-service A310 hosting up to 80 passengers. In 12 sessions the outdoor/recirculation airflow ratio was altered from today’s typically applied fractions to up to 88% recirculation fraction. This leads to increased relative humidity, carbon dioxide (CO2) and Total Volatile Organic Compounds (TVOC) levels in the cabin air, as the emissions by passengers become less diluted by outdoor, dry air. This paper describes the measured increase of relative humidity, CO2 and TVOC level in the cabin air for the different test conditions.