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1.
Exposure to elevated levels of certain volatile organic compounds (VOCs) in households has been linked to deleterious health effects. This study presents the first large-scale investigation of VOC levels in 169 energy-efficient dwellings in Switzerland. Through a combination of physical measurements and questionnaire surveys, we investigated the influence of diverse building characteristics on indoor VOCs. Among 74 detected compounds, carbonyls, alkanes, and alkenes were the most abundant. Median concentration levels of formaldehyde (14 μg/m3), TVOC (212 μg/m3), benzene (<0.1 μg/m3), and toluene (22 μg/m3) were below the upper exposure limits. Nonetheless, 90% and 50% of dwellings exceeded the chronic exposure limits for formaldehyde (9 μg/m3) and TVOC (200 μg/m3), respectively. There was a strong positive correlation among VOCs that likely originated from common sources. Dwellings built between 1950s and 1990s, and especially, those with attached garages had higher TVOC concentrations. Interior thermal retrofit of dwellings and absence of mechanical ventilation system were associated with elevated levels of formaldehyde, aromatics, and alkanes. Overall, energy-renovated homes had higher levels of certain VOCs compared with newly built homes. The results suggest that energy efficiency measures in dwellings should be accompanied by actions to mitigate VOC exposures as to avoid adverse health outcomes.  相似文献   

2.
Basements can influence indoor air quality by affecting air exchange rates (AERs) and by the presence of emission sources of volatile organic compounds (VOCs) and other pollutants. We characterized VOC levels, AERs, and interzonal flows between basements and occupied spaces in 74 residences in Detroit, Michigan. Flows were measured using a steady‐state multitracer system, and 7‐day VOC measurements were collected using passive samplers in both living areas and basements. A walk‐through survey/inspection was conducted in each residence. AERs in residences and basements averaged 0.51 and 1.52/h, respectively, and had strong and opposite seasonal trends, for example, AERs were highest in residences during the summer, and highest in basements during the winter. Airflows from basements to occupied spaces also varied seasonally. VOC concentration distributions were right‐skewed, for example, 90th percentile benzene, toluene, naphthalene, and limonene concentrations were 4.0, 19.1, 20.3, and 51.0 μg/m3, respectively; maximum concentrations were 54, 888, 1117, and 134 μg/m3. Identified VOC sources in basements included solvents, household cleaners, air fresheners, smoking, and gasoline‐powered equipment. The number and type of potential VOC sources found in basements are significant and problematic, and may warrant advisories regarding the storage and use of potentially strong VOCs sources in basements.  相似文献   

3.
Volatile organic compounds (VOCs) as a non-negligible aircraft cabin air quality (CAQ) factor influence the health and comfort of passengers and crew members. On-board measurements of carbonyls (short-chain (C1-C6)) and other volatile organic compounds (VOCs, long-chain (C6-C16)) with a total of 350 samples were conducted in 56 commercial airliner cabins covering 8 aircraft models in this study. The mean concentration for each individual carbonyl compound was between 0.3 and 8.3 μg/m3 (except for acrolein & acetone, average = 20.7 μg/m3) similar to the mean concentrations of other highly detected VOCs (long-chain (C6-C16), 97% of which ranged in 0–10 μg/m3) in aircraft cabins. Formaldehyde concentrations in flights were significantly lower than in residential buildings, where construction materials are known formaldehyde sources. Acetone is a VOC emitted by humans, and its concentration in flights was similar to that in other high-occupant density transportation vehicles. The variation of VOC concentrations in different flight phases of long-haul flights was the same as that of CO2 concentration except for the meal phase, which indicates the importance of cabin ventilation in diluting the gaseous contaminants, while the sustained and slow growth of the VOC concentrations during the cruising phase in short-haul flights indicated that the ventilation could not adequately dilute the emission of VOCs. For the different categories of VOCs, the mean concentration during the cruising phase of benzene series, aldehydes, alkanes, other VOCs (detection rate > 50%), and carbonyls in long-haul flights was 44.2 µg/m3, 17.9 µg/m3, 18.6 µg/m3, 31.5 µg/m3, and 20.4 µg/m3 lower than those in short-haul flights, respectively. Carbonyls and d-limonene showed a significant correlation with meal service (< 0.05). Unlike the newly decorated rooms or new vehicles, the inner materials were not the major emission sources in aircraft cabins. Practical Implications.
  • The on-board measurements of 56 flights enrich the VOC database of cabin environment, especially for carbonyls. The literature review of carbonyls in the past 20 years contributes to the understanding the current status of cabin air quality (CAQ).
  • The analysis of VOC concentration variation for different flight phases, flight duration, and aircraft age lays a foundation for exploring effective control methods, including ventilation and purification for cabin VOC pollution.
  • The enriched VOC data is helpful to explore the key VOCs of aircraft cabin environment and to evaluate the acute/chronic health exposure risk of pollutants for passengers and crew members.
  相似文献   

4.
Nail technicians are exposed to volatile organic compounds (VOCs) from nail products, but no studies have previously measured VOC biomarkers for these workers. This study of 10 nail technicians aimed to identify VOCs in nail salons and explore relationships between air concentrations and biomarkers. Personal and area air samples were collected using thermal desorption tubes during a work shift and analyzed using gas chromatography/mass spectrometry (GC/MS) for 71 VOCs. Whole blood samples were collected pre‐shift and post‐shift, and analyzed using GC/MS for 43 VOCs. Ventilation rates were determined using continuous CO2 measurements. Predominant air VOC levels were ethyl methacrylate (median 240 µg/m3), methyl methacrylate (median 205 µg/m3), toluene (median 100 µg/m3), and ethyl acetate (median 639 µg/m3). Blood levels were significantly higher post‐shift than pre‐shift for toluene (median pre‐shift 0.158 µg/L and post‐shift 0.360 µg/L) and ethyl acetate (median pre‐shift <0.158 µg/L and post‐shift 0.510 µg/L); methacrylates were not measured in blood because of their instability. Based on VOCs measured in these seven nail salons, we estimated that emissions from Greater Boston area nail salons may contribute to ambient VOCs. Ventilation rates did not always meet the ASHRAE guideline for nail salons. There is a need for changes in nail product formulation and better ventilation to reduce VOC occupational exposures.  相似文献   

5.
Hotel housekeepers represent a large, low-income, predominantly minority, and high-risk workforce. Little is known about their exposure to chemicals, including volatile organic compounds (VOCs). This study evaluates VOC exposures of housekeepers, sources and factors affecting VOC levels, and provides preliminary estimates of VOC-related health risks. We utilized indoor and personal sampling at two hotels, assessed ventilation, and characterized the VOC composition of cleaning agents. Personal sampling of hotel staff showed a total target VOC concentration of 57 ± 36 µg/m3 (mean ± SD), about twice that of indoor samples. VOCs of greatest health significance included chloroform and formaldehyde. Several workers had exposure to alkanes that could cause non-cancer effects. VOC levels were negatively correlated with estimated air change rates. The composition and concentrations of the tested products and air samples helped identify possible emission sources, which included building sources (for formaldehyde), disinfection by-products in the laundry room, and cleaning products. VOC levels and the derived health risks in this study were at the lower range found in the US buildings. The excess lifetime cancer risk (average of 4.1 × 10−5) still indicates a need to lower exposure by reducing or removing toxic constituents, especially formaldehyde, or by increasing ventilation rates.  相似文献   

6.
Measurements were taken in new US residences to assess the extent to which ventilation and source control can mitigate formaldehyde exposure. Increasing ventilation consistently lowered indoor formaldehyde concentrations. However, at a reference air exchange rate of 0.35 h?1, increasing ventilation was up to 60% less effective than would be predicted if the emission rate were constant. This is consistent with formaldehyde emission rates decreasing as air concentrations increase, as observed in chamber studies. In contrast, measurements suggest acetaldehyde emission was independent of ventilation rate. To evaluate the effectiveness of source control, formaldehyde concentrations were measured in Leadership in Energy and Environmental Design (LEED)‐certified/Indoor airPLUS homes constructed with materials certified to have low emission rates of volatile organic compounds (VOC). At a reference air exchange rate of 0.35 h?1, and adjusting for home age, temperature and relative humidity, formaldehyde concentrations in homes built with low‐VOC materials were 42% lower on average than in reference new homes with conventional building materials. Without adjustment, concentrations were 27% lower in the low‐VOC homes. The mean and standard deviation of formaldehyde concentration was 33 μg/m3 and 22 μg/m3 for low‐VOC homes and 45 μg/m3 and 30 μg/m3 for conventional.  相似文献   

7.
Correctional centers (prisons) are one of the few non‐residential indoor environments where smoking is still permitted. However, few studies have investigated indoor air quality (IAQ) in these locations. We quantified the level of inmate and staff exposure to secondhand smoke, including particle number (PN) count, and we assessed the impact of the smoking ban on IAQ. We performed measurements of indoor and outdoor PM2.5 and PN concentrations, personal PN exposure levels, volatile organic compounds (VOCs), and nicotine both before and after a complete indoor smoking ban in an Australian maximum security prison. Results show that the indoor 24‐h average PM2.5 concentrations ranged from 6 (±1) μg/m3 to 17 (±3) μg/m3 pre‐ban. The post‐ban levels ranged from 7 (±2) μg/m3 to 71 (±43) μg/m3. While PM2.5 concentrations decreased in one unit post‐ban, they increased in the other two units. Similar post‐ban increases were also observed in levels of PN and VOCs. We describe an unexpected increase of indoor pollutants following a total indoor smoking ban in a prison that was reflected across multiple pollutants that are markers of smoking. We hypothesise that clandestine post‐ban smoking among inmates may have been the predominant cause.  相似文献   

8.
Few measurements of exposure to secondhand smoke (SHS) in close proximity to a smoker are available. Recent health studies have demonstrated an association between acute (<2 h) exposures to high concentrations of SHS and increased risk of cardiovascular and respiratory disease. We performed 15 experiments inside naturally ventilated homes and 16 in outdoor locations, each with 2–4 non‐smokers sitting near a cigarette smoker. The smoker's and non‐smokers' real‐time exposures to PM2.5 from SHS were measured by using TSI SidePak monitors to sample their breathing zones. In 87% of the residential indoor experiments, the smoker received the highest average exposure to SHS, with PM2.5 concentrations ranging from 50–630 μg/m3. During the active smoking period, individual non‐smokers sitting within approximately 1 m of a smoker had average SHS exposures ranging from negligible up to >160 μg/m3 of PM2.5. The average incremental exposure of the non‐smokers was higher indoors (42 μg/m3, = 35) than outdoors (29 μg/m3, = 47), but the overall indoor and outdoor frequency distributions were similar. The 10‐s PM2.5 averages during the smoking periods showed great variability, with multiple high concentrations of short duration (microplumes) both indoors and outdoors.  相似文献   

9.
This study measured air exchange rates, indoor concentrations of aldehydes and volatile organic compounds (VOCs), and radioactivity levels at 19 temporary houses in different temporary housing estate constructed in Minamisoma City following the Great East Japan Earthquake. The 19 surveyed houses represented all of the companies assigned to construct temporary houses in that Minamisoma City. Data were collected shortly after construction and before occupation, from August 2011 to January 2012. Mean air exchange rates in the temporary houses were 0.28/h, with no variation according to housing types and construction date. Mean indoor concentrations of formaldehyde, acetaldehyde, toluene, ethylbenzene, m/p‐xylene, o‐xylene, styrene, p‐dichlorobenzene, tetradecane, and total VOCs (TVOCs) were 29.2, 72.7, 14.6, 6.35, 3.05, 1.81, 7.29, 14.3, 8.32, and 901 μg/m3, respectively. The levels of acetaldehyde and TVOCs exceeded the indoor guideline (48 μg/m3) and interim target (400 μg/m3) in more than half of the 31 rooms tested. In addition to guideline chemicals, terpenes (α‐pinene and d‐limonene) and acetic esters (butyl acetate and ethyl acetate) were often detected in these houses. The indoor radiation levels measured by a Geiger–Müller tube (Mean: 0.22 μSv/h) were lower than those recorded outdoors (Mean: 0.42 μSv/h), although the shielding effect of the houses was less than for other types of buildings.  相似文献   

10.
Emissions from indoor biomass burning are a major public health concern in developing areas of the world. Less is known about indoor air quality, particularly airborne endotoxin, in homes burning biomass fuel in residential wood stoves in higher income countries. A filter‐based sampler was used to evaluate wintertime indoor coarse particulate matter (PM10‐2.5) and airborne endotoxin (EU/m3, EU/mg) concentrations in 50 homes using wood stoves as their primary source of heat in western Montana. We investigated number of residents, number of pets, dampness (humidity), and frequency of wood stove usage as potential predictors of indoor airborne endotoxin concentrations. Two 48‐h sampling events per home revealed a mean winter PM10‐2.5 concentration (± s.d.) of 12.9 (± 8.6) μg/m3, while PM2.5 concentrations averaged 32.3 (± 32.6) μg/m3. Endotoxin concentrations measured from PM10‐2.5 filter samples were 9.2 (± 12.4) EU/m3 and 1010 (± 1524) EU/mg. PM10‐2.5 and PM2.5 were significantly correlated in wood stove homes (r = 0.36, P < 0.05). The presence of pets in the homes was associated with PM10‐2.5 but not with endotoxin concentrations. Importantly, none of the other measured home characteristics was a strong predictor of airborne endotoxin, including frequency of residential wood stove usage.  相似文献   

11.
The literature on the contribution of kerosene lighting to indoor air particulate concentrations is sparse. In rural Uganda, kitchens are almost universally located outside the main home, and kerosene is often used for lighting. In this study, we obtained longitudinal measures of particulate matter 2.5 microns or smaller in size (PM2.5) from living rooms and kitchens of 88 households in rural Uganda. Linear mixed‐effects models with a random intercept for household were used to test the hypotheses that primary reported lighting source and kitchen location (indoor vs outdoor) are associated with PM2.5 levels. During initial testing, households reported using the following sources of lighting: open‐wick kerosene (19.3%), hurricane kerosene (45.5%), battery‐powered (33.0%), and solar (1.1%) lamps. During follow‐up testing, these proportions changed to 29.5%, 35.2%, 18.2%, and 9.1%, respectively. Average ambient, living room, and kitchen PM2.5 levels were 20.2, 35.2, and 270.0 μg/m3. Living rooms using open‐wick kerosene lamps had the highest PM2.5 levels (55.3 μg/m3) compared to those using solar lighting (19.4 μg/m3; open wick vs solar, P=.01); 27.6% of homes using open‐wick kerosene lamps met World Health Organization indoor air quality standards compared to 75.0% in homes using solar lighting.  相似文献   

12.
Partitioning to surfaces is an important sink for volatile organic compounds (VOCs) indoors, but the mechanisms are not well understood or quantified. Here, a mass spectrometer was coupled to a portable surface reactor and a flow tube to measure partitioning of VOCs into paint films coated onto glass or wallboard, and their subsequent diffusion. A model was developed to extract values of the effective absorbing organic mass concentration of the film, Cw, which is a measure of absorption capacity, and VOC diffusion coefficients, Df, from VOC time profiles measured during film passivation and depassivation. Values of Cw agreed well with the value estimated from the paint film mass and flow tube air volume, and Df values (also measured using attenuated total reflectance-Fourier transform infrared spectroscopy) correlated well with VOC vapor saturation concentrations, C*, estimated using a group contribution method. The value of these relationships for estimating key parameters that control VOC partitioning into paint and the fate of VOCs indoors was demonstrated using a house model, which indicated that >50% of VOCs with C* ≤108 μg/m3 (C* of octane, hexanone, and propanol) that contacted a paint film of typical thickness fully permeated the film regardless of emission duration.  相似文献   

13.
To conserve energy, office buildings with air-conditioning systems in Thailand are operated with a tight thermal envelope. This leads to low fresh-air ventilation rates and is thought to be partly responsible for the sick building syndrome symptoms reported by occupants. The objectives of this study are to measure concentrations and to determine sources of 13 volatile organic compounds (VOCs) in office buildings with air-conditioning systems in the business area of Bangkok. Indoor and outdoor air samples from 17 buildings were collected on Tenax-TA sorbent tubes and analyzed for individual VOCs by thermal desorption-gas chromatography/mass spectrometry (TD–GC/MS). Building ventilation was measured with a constant injection technique using hexafluorobenzene as a tracer gas. The results show that the VOC concentrations varied significantly among the studied buildings. The two most dominant VOCs were toluene and limonene with average concentrations of 110 and 60.5 μg m−3, respectively. A Wilcoxon sum rank test indicated that the indoor concentrations of aromatic compounds and limonene were statistically higher than outdoor concentrations at the 0.05 level, while the indoor concentrations of chlorinated compounds were not. Indoor emission factors of toluene and limonene were found to be highest with the average values of 80.9 and 18.9 μg m−2 h−1, respectively. Principal component analysis was applied to the emission factors of 13 VOCs, producing three components based on source similarities. Furthermore, a questionnaire survey investigation and field measurements of building air exchange pointed to indoor air complaints related to inadequate ventilation.  相似文献   

14.
Asthma can be exacerbated by environmental factors including airborne particulate matter (PM) and environmental tobacco smoke (ETS). We report on a study designed to characterize PM levels and the effectiveness of filters on pollutant exposures of children with asthma. 126 households with an asthmatic child in Detroit, Michigan, were recruited and randomized into control or treatment groups. Both groups received asthma education; the latter also received a free-standing high efficiency air filter placed in the child’s bedroom. Information regarding the home, emission sources, and occupant activities was obtained using surveys administered to the child’s caregiver and a household inspection. Over a one week period, we measured PM, carbon dioxide (CO2), environmental tobacco smoke (ETS) tracers, and air exchange rates (AERs). Filters were installed at midweek. Before filter installation, PM concentrations averaged 28 μg m−3, number concentrations averaged 70,777 and 1471 L−1 in 0.3–1.0 and 1–5 μm size ranges, respectively, and the median CO2 concentration was 1018 ppm. ETS tracers were detected in 23 of 38 homes where smoking was unrestricted and occupants included smokers and, when detected, PM concentrations were elevated by an average of 15 μg m−3. Filter use reduced PM concentrations by an average of 69–80%. Simulation models representing location conditions show that filter air flow, room volume and AERs are the key parameters affecting PM removal, however, filters can achieve substantial removal in even "worst" case applications. While PM levels in homes with asthmatic children can be high, levels can be dramatically reduced using filters.  相似文献   

15.
Indoor air quality (IAQ) parameters in 73 primary classrooms in Porto were examined for the purpose of assessing levels of volatile organic compounds (VOCs), aldehydes, particulate matter, ventilation rates and bioaerosols within and between schools, and potential sources. Levels of VOCs, aldehydes, PM2.5, PM10, bacteria and fungi, carbon dioxide (CO2), carbon monoxide, temperature and relative humidity were measured indoors and outdoors and a walkthrough survey was performed concurrently. Ventilation rates were derived from CO2 and occupancy data. Concentrations of CO2 exceeding 1000 ppm were often encountered, indicating poor ventilation. Most VOCs had low concentrations (median of individual species <5 μg/m3) and were below the respective WHO guidelines. Concentrations of particulate matter and culturable bacteria were frequently higher than guidelines/reference values. The variability of VOCs, aldehydes, bioaerosol concentrations, and CO2 levels between schools exceeded the variability within schools. These findings indicate that IAQ problems may persist in classrooms where pollutant sources exist and classrooms are poorly ventilated; source control strategies (related to building location, occupant behavior, maintenance/cleaning activities) are deemed to be the most reliable for the prevention of adverse health consequences in children in schools.  相似文献   

16.
Adding biocides to dispersion products is a well‐known practice to control microbial deterioration. Isothiazolones are among the most commonly used preservatives, in particular a mixture of 2‐methyl‐2H‐isothiazol‐3‐one (MIT) and 5‐chloro‐2‐methyl‐2H‐isothiazol‐3‐one (CIT). In recent years, for health reasons, due to its strong sensitizing effect, CIT has been replaced by 1,2‐benzisothiazol‐3‐one (BIT). Furthermore, numerous products are now available for interiors containing the fungicidal active substance 2‐octyl‐2H‐isothiazol‐3‐one (OIT). So far nearly nothing is known of the emission behavior of BIT and OIT. An analytical method was developed for these two isothiazolones and interior products containing BIT respectively OIT have been investigated in an emission chamber and in test rooms. The chamber tests revealed maximum concentrations of 6.7 μg OIT/m3, 1.9 μg BIT/m3, and 187 μg MIT/m3. Concentrations obtained in the test rooms were at levels up to 1.4 μg OIT/m3 and 29 μg MIT/m3. A noticeable finding was the very slight subsidence of OIT and BIT levels over several weeks. While MIT outgassed quickly, OIT in particular showed low concentrations, but prolonged evaporation.  相似文献   

17.
Little information exists about exposures to volatile organic compounds (VOCs) in early childhood education (ECE) environments. We measured 38 VOCs in single‐day air samples collected in 2010‐2011 from 34 ECE facilities serving California children and evaluated potential health risks. We also examined unknown peaks in the GC/MS chromatographs for indoor samples and identified 119 of these compounds using mass spectral libraries. VOCs found in cleaning and personal care products had the highest indoor concentrations (d‐limonene and decamethylcyclopentasiloxane [D5] medians: 33.1 and 51.4 μg/m³, respectively). If reflective of long‐term averages, child exposures to benzene, chloroform, ethylbenzene, and naphthalene exceeded age‐adjusted “safe harbor levels” based on California's Proposition 65 guidelines (10?5 lifetime cancer risk) in 71%, 38%, 56%, and 97% of facilities, respectively. For VOCs without health benchmarks, we used information from toxicological databases and quantitative structure–activity relationship models to assess potential health concerns and identified 12 VOCs that warrant additional evaluation, including a number of terpenes and fragrance compounds. While VOC levels in ECE facilities resemble those in school and home environments, mitigation strategies are warranted to reduce exposures. More research is needed to identify sources and health risks of many VOCs and to support outreach to improve air quality in ECE facilities.  相似文献   

18.
Current knowledge regarding the association between indoor mold exposures and asthma is still limited. The objective of this case–control study was to investigate the relationship between objectively measured indoor mold levels and current asthma among school‐aged children. Parents completed a questionnaire survey of health history and home environmental conditions. Asthma cases had a history of doctor‐diagnosed asthma or current wheeze without a cold in the past 12 months. Controls were age‐ and sex‐matched to cases. Vacuumed dust samples were collected from the child's indoor play area and mattress. Samples were assessed for mold levels and quantified in colony‐forming units (CFU). Sensitization to mold allergens was also determined by skin testing. Being a case was associated with family history of asthma, pet ownership, and mold allergy. Mold levels (CFU/m2) in the dust samples of children's mattress and play area floors were moderately correlated (= 0.56; < 0.05). High mold levels (≥30 000 CFU/m2) in dust samples from play [adjusted odds ratio (aOR) = 2.6; 95% CI: 1.03–6.43] and mattress (aOR) = 3.0; 95% CI: 1.11–8.00) areas were significantly associated with current asthma. In this study high levels of mold are a risk factor for asthma in children.  相似文献   

19.
Children are particularly vulnerable to many classes of the volatile organic compounds (VOCs) detected in indoor environments. The negative health impacts associated with chronic and acute exposures of the VOCs might lead to health issues such as genetic damage, cancer, and disorder of nervous systems. In this study, 40 VOCs including aldehydes and ketones, aliphatic hydrocarbons, esters, aromatic hydrocarbons, cyclic terpenes, alcohols, and glycol ethers were identified and qualified in different locations at the University of Missouri (MU) Child Development Laboratory (CDL) in Columbia, Missouri. Our results suggested that the concentrations of the VOCs varied significantly among classrooms, hallways, and playground. The VOCs emitted from personal care and cleaning products had the highest indoor levels (2-ethylhexanol-1, 3-carene, homomenthyl salicylate with mean concentration of 5.15 µg/m3, 1.57 µg/m3, and 1.47 µg/m3, respectively). A cancer risk assessment was conducted, and none of the 95th percentile dose estimates exceeded the age-specific no significant risk levels (NSRL) in all classrooms. Dimensionless toxicity index scores were calculated for all VOCs using a novel web-based framework called Toxicological Prioritization Index (ToxPi), which integrates multiple sources of toxicity data. According to the method, homomenthyl salicylate, benzothiazole, 2-ethylhexyl salicylate, hexadecane, and tridecane exhibited diverse toxicity profiles and ranked as the five most toxic indoor VOCs. The findings of this study provide critical information for policy makers and early education professionals to mitigate the potentially negative health impacts of indoor VOCs in the childcare facilities.  相似文献   

20.
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