Exposures to multiple air toxics in New York City

Efforts to assess health risks associated with exposures to multiple urban air toxics have been hampered by the lack of exposure data for people living in urban areas. The TEACH (Toxic Exposure Assessment, a Columbia/Harvard) study was designed to characterize levels of and factors influencing personal exposures to urban air toxics among high school students living in inner-city neighborhoods of New York City and Los Angeles, California. This present article reports methods and data for the New York City phase of TEACH, focusing on the relationships between personal, indoor, and outdoor concentrations in winter and summer among a group of 46 high school students from the A. Philip Randolph Academy, a public high school located in the West Central Harlem section of New York City. Air pollutants monitored included a suite of 17 volatile organic compounds (VOCs) and aldehydes, particulate matter with a mass median aerodynamic diameter 相似文献   

Unmetabolized VOCs in urine as biomarkers of low level exposure in indoor environments

This study aimed to test the possible use of unmetabolized volatile organic compounds (VOCs) in urine as biomarkers of low-level indoor environmental exposure. Twenty-four subjects in 13 dwellings in a prefecture of Japan participated in this study. Air samples of the breathing zone were collected in the living room and bedroom, along with spot urine samples (before bedtime and first morning voids). Toluene, ethylbenzene, xylene isomers, styrene and p-dichlorobenzene in the air and urine samples were measured by gas chromatography/mass spectrometry. For the 21 subjects without solvent exposure at work, there were significant correlations between the time-weighted average air concentrations in the bedroom and morning urinary concentrations for toluene, o-xylene, total xylene and p-dichlorobenzene (correlation coefficients of 0.54, 0.61, 0.56 and 0.84, respectively). Multiple linear regression analysis showed only air VOCs in the bedroom influenced the morning urinary VOC concentrations. We concluded that unmetabolized VOCs in the urine can provide a reliable biological indicator for air VOC exposures in non-occupational environments.     

Exposure assessment of non-electric ice resurfacer operators in indoor ice rinks: a pilot study

Exposure of ice resurfacer operators to indoor air contaminants was measured in six indoor ice arenas. A standardized questionnaire on technical and operational features was employed and indoor airborne concentrations of carbon monoxide (CO), carbon dioxide (CO₂), nitric oxide (NO), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), and total volatile organic compounds (VOCs) were measured. Air samples were collected using a range of direct reading instruments attached to the driver’s seat of the resurfacer. The range of mean exposure concentrations via positional sampling (i.e. as close as able to the operator’s breathing zone) were 5.7–7.4 ppm, 694–2171 ppm, <0.5 to 0.5 ppm, and < 0.1 to 0.2 ppm, for CO, CO₂, NO, and NO₂, respectively. Exposure levels for SO₂ and VOC were below detection. Overall, each of the measured indoor air contaminants was found to be below its respective occupational exposure limits (OEL), suggesting that the risk of hazardous exposure is low. The use of natural gas as a fuel source is believed to contribute to low contaminant concentrations.     

Evaporative gasoline emissions and asthma symptoms

Attached garages are known to be associated with indoor air volatile organic compounds (VOCs). This study looked at indoor exposure to VOCs presumably from evaporative emissions of gasoline. Alaskan gasoline contains 5% benzene making benzene a marker for gasoline exposure. A survey of randomly chosen houses with attached garages was done in Anchorage Alaska to determine the exposure and assess respiratory health. Householders were asked to complete a health survey for each person and a household survey. They monitored indoor air in their primary living space for benzene, toluene, ethylbenzene and xylenes for one week using passive organic vapor monitoring badges. Benzene levels in homes ranged from undetectable to 58 parts per billion. The median benzene level in 509 homes tested was 2.96 ppb. Elevated benzene levels in the home were strongly associated with small engines and gasoline stored in the garage. High concentrations of benzene in gasoline increase indoor air levels of benzene in residences with attached garages exposing people to benzene at levels above ATSDR's minimal risk level. Residents reported more severe symptoms of asthma in the homes with high gasoline exposure (16%) where benzene levels exceeded the 9 ppb.     

Exposure to hazardous air pollutants in underground car parks in Guangzhou,China

Volatile organic compounds (VOCs), carbon monoxide (CO), and PM₁₀ were studied by field sampling in six underground car parks beneath multi-level buildings in Guangzhou, China. CO and PM₁₀ in the car parks range from 3.0 to 69.0 ppm and 0.087 to 0.698 mg m^?3, with mean concentrations of 10.8 ppm and 0.228 mg m^?3, respectively. Overall mean concentrations of methyl tertiary-butyl ether (MTBE), benzene, toluene, ethyl-benzene, and xylene (BTEX) are 90.5, 54.8, 239.9, 47.7, and 189.3 μg m^?3, respectively. Indoor air pollutants in the car parks show an obvious seasonal variation and are higher in winter than in summer. The total estimated cancer risks of occupational exposure for car park staff and casual exposure for parking users are 3.73 × 10^?4 and 5.60 × 10^?6, indicating definite and possible risks, respectively. The hazard quotient of target VOCs is 4.33, implying a definite risk for people using underground car parks. Indoor/outdoor (I/O) ratios for MTBE and BTEX are significantly higher than one, reflecting strong emission sources in underground car parks. The BTEX to MTBE ratios in the car parks are almost the same as those in tunnel air, indicating that indoor aromatic hydrocarbons were mainly from engine emissions and gasoline evaporation. With increasing urbanization in China, more attention should be paid to the exposure of staff and users to hazardous air pollutants in underground car parks.     

Testing the single-pass VOC removal efficiency of an active green wall using methyl ethyl ketone (MEK)

In recent years, research into the efficacy of indoor air biofiltration mechanisms, notably living green walls, has become more prevalent. Whilst green walls are often utilised within the built environment for their biophilic effects, there is little evidence demonstrating the efficacy of active green wall biofiltration for the removal of volatile organic compounds (VOCs) at concentrations found within an interior environment. The current work describes a novel approach to quantifying the VOC removal effectiveness by an active living green wall, which uses a mechanical system to force air through the substrate and plant foliage. After developing a single-pass efficiency protocol to understand the immediate effects of the system, the active green wall was installed into a 30-m³ chamber representative of a single room and presented with the contaminant 2-butanone (methyl ethyl ketone; MEK), a VOC commonly found in interior environments through its use in textile and plastic manufacture. Chamber inlet levels of MEK remained steady at 33.91 ± 0.541 ppbv. Utilising a forced-air system to draw the contaminated air through a green wall based on a soil-less growing medium containing activated carbon, the combined effects of substrate media and botanical component within the biofiltration system showed statistically significant VOC reduction, averaging 57% single-pass removal efficiency over multiple test procedures. These results indicate a high level of VOC removal efficiency for the active green wall biofilter tested and provide evidence that active biofiltration may aid in reducing exposure to VOCs in the indoor environment.     

Main ozone-forming VOCs in the city of Sao Paulo: observations,modelling and impacts

High-ozone concentrations currently represent the main air pollution problem in the city of São Paulo, Brazil. To elucidate the main volatile organic compounds (VOCs), which act as ozone precursors, samples from air quality monitoring stations were evaluated. Thirty-five samples were collected in August–September of 2006 and 43 in July–August of 2008, when the consumption of ethanol was about 50 % of the total fuel used in the São Paulo Metropolitan Area. Samples were collected using electropolished stainless canisters. Chemical analyses were performed on pre-concentrated samples followed by gas chromatograph with flame ionization and mass spectrometry detection. The incremental reactivity scale was used to rank the ozone precursors using the Ozone Isopleth Package for Research (OZIPR) trajectory model coupled with chemical mechanism Statewide Air Pollution Research Center (SAPRC). Sixty-nine species of VOCs were quantified, and the ten main ozone precursors identified in 2008 were as follows: formaldehyde (42.8 %), acetaldehyde (13.9 %), ethene (12.2 %), propene (5.1 %), 1-methylcyclopentene (3.0 %), p-xylene (2.4 %), 1-butene (2.1 %), trans-2-pentene (1.9 %), 2-methyl 2-butene (1.7 %) and trans-2-butene (1.6 %). Volatile organic compound mass distribution showed that in 2008 alkanes represented 46 % of the total VOCs, alkenes 27 %, aromatics 14 %, alkadienes 1 % and aldehydes 12 %.     

Source Apportionment of Volatile Organic Compounds in Tehran, Iran

Identifying the sources of volatile organic compounds (VOCs) is key issue to reducing ground-level ozone and PAN. A multivariate receptor model (Unmix) was used for the determination of the contributions of VOCs sources in Tehran-Iran. Concentrations of ambient C₂–C₁₀ VOCs were measured continuously and online at the center of Tehran city during the winter of 2012. A high correlation coefficient existed between measured and predicted values (R ² = 0.99), indicating that the data were well modeled. Five possible VOCs source categories were identified and mobile sources such as vehicle exhaust (61 %) and fuel evaporation (12 %) more than half of the total VOC concentration. City gas and CNG sources, biogenic source, and industrial solvent source categories accounted for 17 %, 8 % and 2 % of the total VOC, respectively. Result showed Unmix for VOCs source apportionment can be used to analyze and generate air pollution control strategies and policies.     

Indoor air pollutant exposure and determinant factors controlling household air quality for elderly people in Hong Kong

This study investigated the levels and determinant factors of indoor air pollutants including fine particles (PM_2.5), nitrogen dioxide (NO₂), and formaldehyde (HCHO) in 55 households exclusively for the elderly in Hong Kong during summer and winter (Jul.–Sep. 2016 and Nov. 2016–Mar. 2017). The average concentrations of PM_2.5, NO₂, and formaldehyde were 25.3?±?15.0, 40.5?±?16.0, and 26.1?±?22.8 μg/m³ in summer and 34.2?±?19.0, 43.5?±?17.0, and 15.4?±?4.5 μg/m³ in winter, respectively. There were ~?50.3% of households exceeding the World Health Organization indoor air quality standard for PM_2.5 throughout the study, with ~?40.6 and ~61.0% of the households in summer and winter, respectively. The determinant factors for indoor PM_2.5 and NO₂ concentrations were identified as from incense burning and cooking. Cooking with suitable ventilation is an important factor to ease indoor pollutant concentrations. Both of PM_2.5 and NO₂ indoor concentrations showed good correlations with outdoor concentrations. Winter was observed with higher pollutant concentrations than summer except for formaldehyde concentrations. Major factors controlling indoor formaldehyde concentrations are temperature and humidity. The outcome will be useful for the development of future indoor air quality guidelines for Hong Kong.     

Mercury Contamination in Khramulia (Capoeta capoeta) from the Cheshme Kile and Zarrin Gol Rivers in Iran and Human Health Risk Assessment

Fifty-five volatile organic compounds (VOCs) in 738 water samples collected from 33 monitoring sites in the rivers of highly industrialized urban area in Osaka, Japan, 1993–2006 were analyzed. VOCs could be classified into three groups by the detection frequency and levels of mean concentrations detected. Firstly, for 30 compounds, almost all data were non detection or were around the detection limits. Secondly, for 11 compounds, higher values were occasionally observed at some sites. Thirdly, VOCs were ubiquitously found at relatively high or high levels. Spatial distributions of mean concentrations of the most ubiquitous VOCs throughout 13 years have shown exponentially decreasing trends towards the downstream direction of the rivers. Time series of mean concentrations of all sites of five solvents have shown monotonically downward trends. In contrast, three disinfection by-products and six gasoline compounds were not decreasing.     

家俱展销厅空气中甲醛和挥发性有机物污染的调查

目的了解家俱展销厅室内空气中甲醛和挥发性有机物（VOCs）的污染状况、影响因素和对从业人员健康的影响。方法随机选择某市25家家俱展销厅和10家食品超市，分别对其室内空气中甲醛、VOCs和相关影响因素进行监测，并对其从业人员的不良建筑物综合症进行问卷调查。结果家俱销售厅室内空气中甲醛和VOCs的平均浓度分别为0．170mg／m^3和1．01mg／m^3，为《室内空气质量标准》的1．7倍和1．68倍，达标率分别为20％和24％。甲醛和VOCs的浓度与展销厅中的温度和湿度呈正相关，与风速呈负相关。甲醛和VOCs含量均较食品超市空气中的含量高（P〈0．05），家俱销售人员的不良建筑物综合症发生率高于食品超市营业员（P〈0．05）。结论家俱销售厅室内空气中甲醛、VOCs等污染严重，并对家俱销售人员的健康造成一定的危害，其污染程度受室内温度、湿度、通风状况和家俱使用材料类型的影响。     

Personal, indoor, and outdoor VOC exposures in a probability sample of children

As part of the Minnesota Children's Pesticide Exposure Study we measured volatile organic compound (VOC) concentrations in a probability sample of households with children. The 6-day average concentrations for 10 common VOCs were obtained in urban and nonurban residences twice during this multiphase study: screening-phase indoor measurements were collected in 284 households, and in the intensive-phase matched outdoor (O), indoor (I), and personal (P) measurements were collected in a subset (N=72) of the screened households. Screening-phase households with smokers had significantly higher concentrations of benzene and styrene compared to nonsmoking households; households with an attached garage had significantly higher levels of benzene, chloroform, styrene, and m/p- and o-xylene compared to households without an attached garage; and nonurban residences, which had a greater prevalence of smokers and attached garages, had significantly higher 1,1,1-trichloroethane, styrene, and toluene and significantly lower tetrachloroethylene concentrations compared to urban households. The screening-phase weighted distributions estimate the mean and variability in indoor VOC concentrations for more than 45,000 households with children in the census tracts sampled. Overall, median indoor concentrations of most VOCs measured in this study were similar to or lower than indoor levels measured previously in the United States. Intensive-phase outdoor VOC concentrations were generally lower than other major metropolitan areas, but urban concentrations were significantly higher than nonurban concentrations for all compounds except 1,1,1-trichloroethylene. A consistent pattern of P>I>O was observed for nine of 10 VOCs, with 1,1,1-trichloroethylene (I>P>O) being the only exception to this pattern. For most children, the indoor at-home microevironment was strongly associated with personal exposure after controlling for important covariates, but the ratio of median to upper bound exposures was smaller than that observed in studies of adults. There are relatively little data on VOC exposures in children, so these results are useful for estimating the central tendency and distribution of VOC exposures in locations where children spend a majority of their time.     

A cancer risk assessment of inner-city teenagers living in New York City and Los Angeles

BACKGROUND: The Toxics Exposure Assessment Columbia-Harvard (TEACH) project assessed exposures and cancer risks from urban air pollutants in a population of high school teenagers in New York City (NYC) and Los Angeles (LA). Forty-six high school students participated in NYC and 41 in LA, most in two seasons in 1999 and 2000, respectively. METHODS: Personal, indoor home, and outdoor home 48-hr samples of volatile organic compounds (VOCs), aldehydes, particulate matter with aerodynamic diameter < or = 2.5 microm, and particle-bound elements were collected. Individual cancer risks for 13 VOCs and 6 particle-bound elements were calculated from personal concentrations and published cancer unit risks. RESULTS: The median cumulative risk from personal VOC exposures for this sample of NYC high school students was 666 per million and was greater than the risks from ambient exposures by a factor of about 5. In the LA sample, median cancer risks from VOC personal exposures were 486 per million, about a factor of 4 greater than ambient exposure risks. The VOCs with the highest cancer risk included 1,4-dichlorobenzene, formaldehyde, chloroform, acetaldehyde, and benzene. Of these, benzene had the greatest contributions from outdoor sources. All others had high contributions from indoor sources. The cumulative risks from personal exposures to the elements were an order of magnitude lower than cancer risks from VOC exposures. CONCLUSIONS: Most VOCs had median upper-bound lifetime cancer risks that exceeded the U.S. Environmental Protection Agency (EPA) benchmark of 1 x 10-6 and were generally greater than U.S. EPA modeled estimates, more so for compounds with predominant indoor sources. Chromium, nickel, and arsenic had median personal cancer risks above the U.S. EPA benchmark with exposures largely from outdoors and other microenvironments. The U.S. EPA-modeled concentrations tended to overestimate personal cancer risks for beryllium and chromium but underestimate risks for nickel and arsenic.     

Belastung der Raumluft privater Neubauten mit flüchtigen organischen Verbindungen

The concentration of volatile organic compounds (VOCs) in indoor air of 188 living, sleeping and children's rooms in 64 newly erected private homes has been investigated. 59 VOCs typically emitted from building materials were determined, mainly aromatic and aliphatic hydrocarbons, terpenes, alcohols and glycol derivatives. The median and the reference level for the sum of the VOCs quantified were 302 μg/m³ and 832 μg/m³, respectively; the highest concentration amounted to 1473 μg/m³. The contribution of monoterpenes was about 50%, while the concentrations of aromatic and aliphatic hydrocarbons decreased in the past years. For 30 out of 182 rooms unpleasant odor and/or health problems were mentioned by the occupants. In rooms with unpleasant odor significantly higher VOC concentrations were determined. Wooden parquetry and panelling resulted in higher VOC concentrations, especially terpenes and aliphatic hydrocarbons.     

Asthmatic symptoms and volatile organic compounds, formaldehyde, and carbon dioxide in dwellings.

OBJECTIVES--As a part of the worldwide European Community respiratory health survey, possible relations between symptoms of asthma, building characteristics, and indoor concentration of volatile organic compounds (VOCs) in dwellings were studied. METHODS--The study comprised 88 subjects, aged 20-45 years, from the general population in Uppsala, a mid-Swedish urban community, selected by stratified random sampling. Room temperature, air humidity, respirable dust, carbon dioxide (CO2), VOCs, formaldehyde, and house dust mites were measured in the homes of the subjects. They underwent a structured interview, spirometry, peak expiratory flow (PEF) measurements at home, methacholine provocation test for bronchial hyperresponsiveness, and skin prick tests. In addition, serum concentration of eosinophilic cationic protein (S-ECP), blood eosinophil count, and total immunoglobulin E (S-IgE) were measured. RESULTS--Symptoms related to asthma were more common in dwellings with house dust mites, and visible signs of dampness or microbial growth in the building. Significant relations were also found between nocturnal breathlessness and presence of wall to wall carpets, and indoor concentration of CO2, formaldehyde, and VOCs. The formaldehyde concentration exceeded the Swedish limit value for dwellings (100 micrograms/m3) in one building, and CO2 exceeded the recommended limit value of 1000 ppm in 26% of the dwellings, showing insufficient outdoor air supply. Bronchial hyperresponsiveness was related to indoor concentration of limonene, the most prevalent terpene. Variability in PEF was related to two other terpenes; alpha-pinen and delta-karen. CONCLUSION--Our results suggest that indoor VOCs and formaldehyde may cause asthma-like symptoms. There is a need to increase the outdoor air supply in many dwelling, and wall to wall carpeting and dampness in the building should be avoided. Improved indoor environment can also be achieved by selecting building materials, building construction, and indoor activities on the principle that the emission of volatile organic compounds should be as low as reasonably achievable, to minimise symptoms related to asthma due to indoor air pollution.     

室内装修后空气中挥发性有机物污染状况调查分析

目的了解居室装修后室内空气中主要挥发性有机物污染状况。方法对居室装潢后不同时间的居室室内空气中甲醛、苯、甲苯、二甲苯、空气耗氧量进行测定,并与室外空气标准进行对比。结果装修后居室空气中甲醛、苯、二甲苯及空气耗氧量均严重超标,12个月后浓度虽明显下降,但甲醛和空气耗氧量超过室外空气标准。结论装修后相当长一段时间内居室空气中挥发性有机物污染严重,装修后1年内入住可能至少导致为期1~2年的免疫伤害。     

Seasonal evaluation of fine and coarse culturable bacterial aerosols from residences within a rural and an urban city in Egypt

Non-complaint Egyptian homes were examined to determine the residential culturable airborne bacterial concentrations so that these could be used as comparisons in indoor air quality investigations. Concentrations of airborne bacteria were investigated in 26 urban flats across Cairo and 17 rural flats in the Dakahlia governorate. Air samples were collected using a two-stage viable cascade impactor sampler, dividing particles into coarse (>8 μm) and fine (<8 μm) sizes. For urban flats, the year's median indoor and comparison site concentrations were 9133 CFU/m³ and 9423 CFU/m³, respectively. For rural flats, the year's median indoor and comparison site concentrations were 15,915 CFU/m³ and 10,859 CFU/m³, respectively. The median indoor bacterial concentrations increased in winter and spring compared to autumn and summer. Winter months had the greatest median concentration for coarse indoor organisms, whereas spring had the largest for the fine indoor organisms. Fine bacterial concentration composed more than 60% of the indoor bacterial fraction.     

室内挥发性有机物的来源及其健康效应

挥发性有机物 (VOCs)作为一大类空气污染物 ,是近几年来室内空气污染的热点问题 ,现代人一天之中有 90 %的时间在室内度过 ,所以VOCs对人体健康有着极大的危害 ,本文主要综述了VOCs的来源、种类及其对人体健康的影响。