Volatile organic compounds (VOCs) and air mutagenicity: Results of one year monitoring at an urban site

The concentrations of four volatile organic compounds (VOCs: benzene, toluene, ethylbenzene and xylenes) and the levels of inhalable (< 10 μm) airborne particles were monitored during 1 year at a site with intense vehicular traffic in the city of Rome. VOCs as well as airborne particulate matter were sampled every alternate day and pooled in fortnightly samples representative of the first and second half of each month. Some meteorological parameters (mean temperature, heliophany, air pressure and relative humidity) were concurrently recorded. Air particulate extracts were tested for mutagenicity in the Salmonella reversion system with tester strain TA98. Air mutagenicity levels were compared to air concentrations of benzene and alkylbenzenes, putative indicators of vehicular traffic, in order to elucidate their interrelationships. The results of multivariate statistical analyses show that seasonal variations in air mutagenicity are mainly dependent on the increased content of organic matter in airborne particles, possibly resulting from the increased deposition rate of semivolatile compounds with low ambient temperature. A weaker association was observed between air mutagenicity level and VOCs concentrations.     

Correlations between mutagenicity of airborne particles and concentrations of air pollutants]

With highly efficient aspirometry method there were sampled airborne particles in different parts of Wroc?aw in winter and summer. Organic compounds adsorbed on the particles were extracted for 8 hours in Soxhlet apparatus. Concentration of PAHs and benzo(a)pyrene was determined with GC-MS. Mutagenicity of particles was examined with Ames test. Concentrations of airborne particles ranged from 17-144 mg/m3, and organic compounds adsorbed on the particles--1.1-28.6 mg/m3. Concentrations of PAHs from EPA list ranged from 8.3-1211.6 ng/m3, benzo(a)pyrene's ones--from 4.5-709 ng/m3. Airborne particles sampled in many different locations of Wroc?aw in winter and summer displayed mutagenic activity. Air volumes polluted with the particles resulting in mutagenic effect in Ames test in TA 98 strain without activation with fraction S9 ranged from 0.25-42.5 m3. They displayed correlation with concentration of airborne particles (correlation index -0.35), organic compounds adsorbed on the particles (correlation index -0.58), PAHs from EPA list (correlation index -0.52) and benzo(a)pyrene (correlation index -0.52). Physiochemical indexes of air pollution only approximately indicate health hazards caused by mutagenes and cancergenes adsorbed on airborne particles. Therefore monitoring of air pollution should be supplemented with testing their mutagenicity with Ames test.     

Genotoxicity of total and fractionated extractable organic matter in fine air particulate matter from urban Guangzhou: comparison between haze and nonhaze episodes

To investigate the genotoxic potencies of extractable organic matter (EOM) in aerosols, fine air particulate matter (PM(2.5)) was collected simultaneously at a roadside (1.2 m above ground) and at a rooftop location (50 m above ground) in urban Guangzhou (China) during a nonhaze period in September 2006 and a haze period in October 2006. Particle-bound organics were extracted and separated into aliphatic, aromatic, and polar fractions. The genotoxicity of total and fractionated extracts were tested by single-cell electrophoresis (comet assay) with human blood lymphocytes. The PM(2.5) concentrations usually exceeded the U.S. National Ambient Air-Quality Standard level (65 microg/m(3)) at both the roadside and the rooftop. During nonhaze days, the roadside samples showed substantially higher PM(2.5) levels (108-130 microg/m(3)) and significantly higher genotoxic effects of total and fractionated EOM (p < 0.05 for >10 m(3) air equivalent/ml) than the rooftop samples. During haze days, however, PM(2.5) levels and genotoxic potencies of rooftop samples were drastically elevated and comparable to those of roadside samples, implying that during haze episodes, most people in the urban area are exposed to PM(2.5) pollution as serious as in the heavily polluted roadside microenvironment. All total EOM samples showed significant (p < 0.05) dose-response effects, and their effects as olive tail moment were less than the sums of the three fractions. Aromatic fractions of EOM exhibited the greatest genotoxic potencies, but polar fractions also contributed substantially to DNA-damaging effects. Polycyclic aromatic hydrocarbons and nitrated derivatives likely are the most important species responsible for the genotoxicity of EOM in PM(2.5).     

Correlation between mutagenicity of airborne particles and air pollution parameters in eleven Italian towns

Organic extracts from airborne particles collected in 11 Italian towns between February and April, 1988, were tested for mutagenicity on TA98 and TA100 (± S9), and their nitroreductase (NR) deficient Salmonella strains, by the use of the Ames plate incorporation assay. Mutagenic responses were fitted by an equation which takes into account toxic effects on tester organisms. Generally parallel responses were obtained with the two Salmonella strains, but the TA98 gave, mostly, higher increases of revertants over the control level. No dramatic decreases in mutagenicity were observed with the NR derivative strains, except in a few cases with TA98NR and, more frequently, with TA100NR strains. During air sampling, temperature, atmospheric pressure, light, wind strength and direction, SO₂, CO, NO₂, O₃ and non‐methanic hydrocarbons (NMHC) concentrations were continuously monitored. Meteorological variables seem not to be significantly correlated with mutagenicity variations, while the highest correlation (r = 0.91) was observed between induced reversion in TA98 (+ S9) and NMHC concentration in air. Therefore, in spite of the wide range of different types of towns included in the study, air NMHC concentration can be considered a good predictor for the mutagenicity of the total organic material extracted from particles of urban air.     

人员活动和空气净化器对支气管镜室空气微生物和颗粒物的影响

目的评价人员活动和空气净化器对支气管镜室空气微生物及颗粒物的影响。方法依照支气管镜室有无人员活动和空气净化器,将实验分成四组:动态无净化组、动态净化组、静态无净化组、静态净化组,在五个不同时间点(0、0.5、1、2、4 h)对室内空气进行采样和分析,用浮游菌法采集空气中的微生物并培养、计数,用DT-9881M激光尘埃粒子计数器检测颗粒物浓度,统计方法采用析因设计的方差分析。结果动态无净化组的细菌、真菌、总微生物(细菌+真菌)、PM_(2.5)和PM_(2.5~10.0)菌落数/浓度分别为(113.53±7.78)CFU/m~3、(89.67±7.17)CFU/m~3、(203.20±10.92)CFU/m~3、(86 557.20±4 158.29)个/m~3和(659.69±38.91)个/m~3,静态无净化组分别为(84.33±3.65)CFU/m~3、(65.00±2.65)CFU/m~3、(149.33±4.98)CFU/m~3、(45 812.64±1 279.61)个/m~3和(189.15±4.64)个/m~3,动态净化组分别为(84.80±8.08)CFU/m~3、(90.40±5.50)CFU/m~3、(175.20±9.22)CFU/m~3、(49 336.38±2 039.16)个/m~3和(218.36±7.02)个/m~3,静态净化组分别为(67.80±5.63)CFU/m~3、(38.27±3.70)CFU/m~3、(106.07±6.76)CFU/m~3、(29 772.53±2 212.93)个/m~3和(124.80±7.16)个/m~3,细菌、总微生物、PM_(2.5)、PM_(2.5~10.0)菌落数/浓度动态组高于静态组,无净化组高于净化组(均P0.05),真菌菌落数动态无净化组高于静态无净化组,静态净化组低于静态无净化组(均P0.05),动态净化组与无净化组间无明显差异(P=0.936)。结论人员活动增加支管镜室空气微生物和颗粒物的菌落数/浓度,空气净化器能降低支气管镜室空气中的细菌、总微生物和颗粒物的菌落数/浓度。     

Influences of study design and location on the relationship between particulate matter air pollution and birthweight

A large number of studies have identified a relationship between particulate matter air pollution and birthweight. Although reported associations are small and varied, they have been identified in studies from places around the world. Exposure assignment, covariates and study inclusion criteria vary among studies. To examine the effect of these and other study characteristics on associations between particulate matter and birthweight, US birth records for singletons delivered at 40 weeks gestation in 2001-03 during the months of March, June, September and December were linked to quarterly estimates of pollution exposure, both particulate matter exposure and exposure to multiple pollutants, by county of residence and month of birth. Annual, 9-month and trimester-specific exposures were assigned. Among births linked to particulate matter exposure there was a small association between coarse particle exposure and birthweight (beta -13 g per 10 microg/m(3) increase [95% CI -18.3 g, -7.6 g]) after controlling for maternal factors; this association was attenuated slightly and remained statistically significant after further adjustment for contextual factors, year of birth, region, or urban-rural status. The associations were slightly weaker among births linked to multiple pollutant exposure than among births linked to just particulate matter exposure. The association varied markedly by region, ranging from a decrement of 43 g per 10 microg/m(3)[95% CI -58.6 g, -27.6 g] in the north-west to a null association in the south-west. Trimester findings were smaller, yet remained significant and varied regionally. The association between fine particle exposure and birthweight varied considerably, with an overall small positive association that became null after control for region. This study found that wide regional differences in association may contribute to the varied published findings. The association between coarse particle exposure and birthweight appeared robust, if small; fine particles had no overall association with birthweight.     

Fungal spore concentrations in indoor and outdoor air in university libraries,and their variations in response to changes in meteorological variables

The fungal spore concentration (FSC) in the air poses a risk for human health. This work studied the FSC in university libraries and how it is affected by environmental factors. A total of 347 samples were obtained using a Microbio MB2^® Aerosol Sampler. The wind speed (WS), cross wind (CW), temperature (T), relative humidity (HR), barometric pressure (BP) and dew point (DP) were recorded using a Kestrel^® 4500 weather station. The median indoor/outdoor FSC was 360/1230?CFU?m^?3. FSC correlated inversely with BP, HR and DP; and positively with WS and CW; whereas T showed negative or positive correlation with FSC, depending on the region or sampling time. Eleven fungal genera were found and the dominant isolates were identified as Aspergillus niger, Aspergillus tamarii and Aspergillus oryzae. All fungi identified are known to be allergenic. It was concluded that environmental variables can influence the air FSC in different ways.     

大气颗粒物与居民脑卒中发作 或死亡之间关系的Meta分析

目的 研究大气颗粒物污染(PM10、PM25)与居民脑卒中发作或死亡之间的关系.方法 检索文献数据库,应用Meta分析法对符合文献纳入标准的16个有关大气颗粒物与居民脑卒中每日发作或死亡关系的定量研究进行综合分析.根据异质性检验结果选用固定效应模型或随机效应模型,采用大气颗粒物每上升10 μg/m3,居民脑卒中死亡的危险度(OR)为效应值进行效应值合并,做敏感性分析.结果 PM10浓度每上升10 μg/m3,居民脑卒中发作的OR=1.011(95%CI:1.001～1.021),即发作增加1.09%(95%CI:0.10%～2.08%),死亡的OR=1.007(95%CI:1.006～1.008),即死亡增加0.70%(95%CI:0.60%～0.80%),说明PM10浓度上升与居民脑卒中发作或死亡均有统计学相关,敏感性分析结果均稳定;PM25浓度每上升10 μg/m3,居民脑卒中发作的OR=1.001(95%CI:0.992～1.010),死亡的OR=1.052(95%CI:0.958～1.154).结论 研究结果表明PM10的空气污染对居民脑卒中发作率和死亡率的增加有统计学相关,PM25浓度增高与脑卒中发作或死亡无统计学相关.     

室内颗粒物污染对儿童哮喘的影响

目的探讨室内大气PM_(10)、PM_(2.5)、PM1污染对儿童哮喘的影响。方法采用1∶1成组病例-对照研究,于2015年10月—2016年5月对石河子市80名哮喘儿童和80名健康对照儿童进行问卷调查与室内颗粒物浓度检测,分析儿童哮喘的危险因素。结果两组合计160名儿童的室内PM_(10)、PM_(2.5)、PM1浓度范围分别为26.57~507.30、12.66~159.00、4.53~77.08μg/m~3,其中PM_(10)超标率为61.9%,PM_(2.5)超标率为6.9%。病例组室内空气中的PM_(10)、PM_(2.5)、PM1浓度中位数均高于对照组,差异有统计学意义(P0.01)。多因素logistic回归分析结果显示,儿童有过敏史(OR=5.171)、有环境烟草烟雾(ETS)暴露(OR=2.429)、PM_(2.5)浓度高于中位数(OR=3.459)是儿童哮喘的危险因素,母乳喂养(OR=0.454)是儿童哮喘的保护因素,均有统计学意义(P0.05)。结论儿童有过敏史、ETS暴露和PM_(2.5)暴露可能增加儿童哮喘风险,同时应提倡母乳喂养,以保护儿童呼吸系统健康。     

Saharan dust and associations between particulate matter and daily mortality in Rome, Italy

Background: Outbreaks of Saharan-Sahel dust over Euro-Mediterranean areas frequently induce exceedances of the Europen Union''s 24-hr standard of 50 μg/m³ for particulate matter (PM) with aerodynamic diameter ≤ than 10 μm (PM₁₀).Objectives: We evaluated the effect of Saharan dust on the association between different PM fractions and daily mortality in Rome, Italy.Methods: In a study of 80,423 adult residents who died in Rome between 2001 and 2004, we performed a time-series analysis to explore the effects of PM_2.5, PM_2.5–10, and PM₁₀ on natural, cardiac, cerebrovascular, and respiratory mortality. We defined Saharan dust days by combining light detection and ranging (LIDAR) observations and analyses from operational models. We tested a Saharan dust–PM interaction term to evaluate the hypothesis that the effects of PM, especially coarse PM (PM_2.5–10), on mortality would be enhanced on dust days.Results: Interquartile range increases in PM_2.5–10 (10.8 μg/m³) and PM₁₀ (19.8 μg/m³) were associated with increased mortality due to natural, cardiac, cerebrovascular, and respiratory causes, with estimated effects ranging from 2.64% to 12.65% [95% confidence interval (CI), 1.18–25.42%] for the association between PM_2.5–10 and respiratory mortality (0- to 5-day lag). Associations of PM_2.5–10 with cardiac mortality were stronger on Saharan dust days (9.73%; 95% CI, 4.25–15.49%) than on dust-free days (0.86%; 95% CI, –2.47% to 4.31%; p = 0.005). Saharan dust days also modified associations between PM₁₀ and cardiac mortality (9.55% increase; 95% CI, 3.81–15.61%; vs. dust-free days: 2.09%; 95% CI, –0.76% to 5.02%; p = 0.02).Conclusions: We found evidence of effects of PM_2.5–10 and PM₁₀ on natural and cause-specific mortality, with stronger estimated effects on cardiac mortality during Saharan dust outbreaks. Toxicological and biological effects of particles from desert sources need to be further investigated and taken into account in air quality standards.     

北京市大气颗粒物中多环芳烃及碳元素分析

目的了解大气颗粒物PM_2.5与PM₁₀中多环芳烃及有机碳、元素碳的污染特征。方法2006年6月16～18日和6月20～22日于北京市城区设置采样点,采集大气颗粒物PM_2.5与PM₁₀,并对其中的17种多环芳烃及有机碳、元素碳进行了分析。结果PM_2.5与PM₁₀中多环芳烃的平均质量浓度分别为0.011～2.846和0.013～4.415ng/m³;PM_2.5与PM₁₀中有机碳和元素碳的平均质量浓度分别为28.56,8.75μg/m³和41.14,15.43μg/m³。结论采样时间内,4环和5环多环芳烃是PM_2.5与PM₁₀中17种多环芳烃的主要成分;含碳组分在PM_2.5与PM₁₀中所占比例相当,碳仍然是2种粒子中的主要成分之一。     

Out-of-hospital cardiac arrest and airborne fine particulate matter: a case-crossover analysis of emergency medical services data in Indianapolis, Indiana

BACKGROUND: Previous studies have found particulate matter (PM) < 2.5 microm in aerodynamic diameter (PM2.5) associated with heart disease mortality. Although rapid effects of PM2.5 exposure on the cardiovascular system have been proposed, few studies have investigated the effect of short-term exposures on out-of-hospital cardiac arrest (OHCA). OBJECTIVES: We aimed to determine whether short-term PM2.5 exposures increased the risk of OHCA and whether risk depended on subject characteristics or presenting heart rhythm. METHODS: A case-crossover analysis determined hazard ratios (HRs) for OHCAs logged by emergency medical systems (EMS) versus hourly and daily PM2.5 exposures at the time of the OHCA and for daily and hourly periods before it. RESULTS: For all OHCAs (n = 1,374), exposures on the day of the arrest or 1-3 days before arrest had no significant effect on the incidence of OHCA. For cardiac arrests witnessed by bystanders (n = 511), OHCA risk significantly increased with PM2.5 exposure during the hour of the arrest (HR for a 10-microg/m3 increase in PM2.5 exposure = 1.12; 95% confidence interval, 1.01-1.25). For the subsets of subjects who were white, 60-75 years of age, or presented with asystole, OHCA risk significantly increased with PM2.5 during the hour of the arrest (HRs for a 10-microg/m3 increase in PM2.5 = 1.18, 1.25, or 1.22, respectively; p < 0.05). HR generally decreased as the time lag between PM2.5 exposure and OHCA increased. CONCLUSION: The results suggest an acute effect of short-term PM2.5 exposure in precipitating OHCAs, and a need to investigate further the role of subject factors in the effects of PM on the risk of OHCA.     

郊区和城区空气污染物浓度差异及与儿童哮喘患病情况的关系

目的 探索郊区和城区空气污染物浓度差异及空气污染指数与儿童哮喘患病情况的关系,为哮喘防治提供理论依据。方法 本次研究对象为2017年1月—2019年12月期间中国医科大学附属盛京医院收治的211例哮喘患儿,均进行肺功能、哮喘评分评估,同时选取辽宁省沈阳市城区面积23.71 km²,郊区面积22.86 km²进行空气污染物浓度检测,并分析城区、郊区空气污染物、儿童哮喘患病情况之间的关系。结果 城区空气污染物中总计PM₁₀浓度[(0.139±0.032)mg/m³]、API浓度(65.455±8.741)、PM_2.5[(0.061±0.010)mg/m³]高于郊区空气中总计PM₁₀浓度[(0.048±0.012)mg/m³]、API浓度(56.955±8.774)、PM_2.5[(0.061±0.010)mg/m³](t=24.256、6.827、17.575,P<0....     

室内可吸入颗粒物污染与哮喘和肺癌的相关性研究综述

室内可吸入颗粒物(inhalable particulate matter,PM₁₀)污染可能受室外PM₁₀污染影响,但其主要来源、成分与室外PM₁₀存在较大差异。大气污染越来越严重,哮喘和肺癌发病率的升高使人们更加关注PM₁₀与哮喘、肺癌的关系。室内空气污染尤其是室内PM₁₀污染在肺癌、哮喘发生发展中的作用成为学者们研究的新重点。本文从室内PM₁₀污染现状、室内PM₁₀污染与哮喘、肺癌的相关性进行了综述。现有研究结果提示室内PM₁₀可能与哮喘、肺癌的发生发展相关,但尚缺乏强有力的全面系统深入的实证研究,结论尚待进一步探究。今后应加强对室内PM₁₀主要污染成分对疾病作用机理方面的深究。     

Mutagenic activity of airborne particulate matter (PM10) in a sugarcane farming area (Araraquara city, southeast Brazil)

Brazil contains 25% of the total land planted with sugarcane in the world and is thus one of the major producers. The annual burning of sugarcane fields prior to harvesting emits huge amounts of pyrogenic particles. Biomass burning is an important primary and secondary source of aerosol particles. The presence of carbonaceous particles in the inhalable size range makes it important to study this fraction in view of the possible effects on human health and the climate. In this study, the mutagenic activity associated with inhalable airborne particulate matter (PM₁₀) collected on air filters in a sugarcane-growing area near the city of Araraquara (SE Brazil) was determined. The extracts were dissolved in dimethylsulfoxide and tested for mutagenicity by the Ames plate incorporation test with Salmonella typhimurium YG1024 in the presence and absence of the S9 mixture. To assess the association between mutagenicity and PM₁₀, samples were collected in sugarcane harvesting and non-harvesting periods of the year. Significant mutagenicity was detected in organic solvent extracts of all samples, with differences between the two periods. The highest values of mutagenic potency (13.45 and 5.72 revertants/m³ of air in the absence and presence of the S9 mixture, respectively) were observed during the harvest. In this period, a Teflon™-coated glass-fiber air filter trapped 67.0 μg of particulate matter per m³ of air. In the non-harvest period, on the same type of filter, only 20.9 μg of particulate matter was found per m³. The mutagenic potencies at this time were 1.30 and 1.04 revertants/m³ of air, in the absence and presence of the S9 mixture, respectively. Period, concentration of PM₁₀ and mutagenicity were associated with each other. For routine monitoring of mutagenicity in the atmosphere, the use of YG1024 tester strain without metabolic activation (S9) is recommended.     

Association between ambient particulate matter and daily cause-specific mortality in Tanggu,Tianjin Binhai New Area,China

The aim of the study was to determine whether the area of Tanggu, Tianjin Binhai New Economic Developing Area, China, is subject to similar effects of ambient particulate matter less than 10 micrometres in aerodynamic diameter (PM10) similar to other areas of China. This study was designed to investigate cause-specific mortality risks associated with air pollution in this geographical region. The present study used a time-series analysis to explore the relationship between PM10 and the cause-specific mortalities for non-accidental, cardiovascular, and cardiopulmonary mortality from 1 January 2006 to 31 December 2010. A 10 μg/m³ increment of PM10 was associated with a 1.02% (95% confidence interval (CI): 0.48, 1.56) increase in cardiovascular mortality, and a 0.88% (95% CI: 0.36, 1.39) increase in cardiopulmonary mortality. In addition, the effects from PM10 appear to be consistent with multi-pollutant models. The results show that there are strong associations between daily cardiovascular and cardiopulmonary mortality and ambient PM10 exposure.     

空气污染与儿童哮喘发病机制的研究进展

我国多地区雾霾严重,空气质量堪忧。大气污染成因复杂,大气颗粒物的来源更为复杂多变。常见的空气污染物种类繁多,如交通相关空气污染物、多环芳香烃、香烟烟雾、尘埃颗粒及细颗粒物 PM2.5,均与儿童哮喘密切相关,其毒性组分和致毒机制尚不明确,健康效应和毒理机制已经成为前沿的科学热点问题之一。本文就近几年来关于空气污染加重或引起儿童哮喘的机制进行综合分析。     

Socioeconomic status, particulate air pollution, and daily mortality: differential exposure or differential susceptibility

BACKGROUND: Short-term increases in particulate air pollution are linked with increased daily mortality and morbidity. Socioeconomic status (SES) is a determinant of overall health. We investigated whether social class is an effect modifier of the PM(10) (particulate matter with diameter <10 micron)-daily mortality association, and possible mechanisms for this effect modification. METHODS: Area-based traffic emissions, income, and SES were available for each resident in Rome. All natural deaths (83,253 subjects) occurring in Rome among city residents (aged 35+ years) during the period 1998-2001 were identified. For each deceased individual, all the previous hospitalizations within 2 years before death were available via a record linkage procedure. PM(10) daily data were available from two urban monitoring sites. A case-crossover analysis was utilized in which control days were selected according to the time stratified approach (same day of the week during the same month). Conditional logistic regression was used. RESULTS: Due to the social class distribution in the city, exposure to traffic emissions was higher among those with higher area-based income and SES. Meanwhile, people of lower social class had suffered to a larger extent from chronic diseases before death than more affluent residents, especially diabetes mellitus, hypertension, heart failure, and chronic obstructive pulmonary diseases. Overall, PM(10) (lag 0-1) was strongly associated with mortality (1.1% increase, 95%CI = 0.7-1.6%, per 10 microg/m(3)). The effect was more pronounced among persons with lower income and SES (1.9% and 1.4% per 10 microg/m(3), respectively) compared to those in the upper income and SES levels (0.0% and 0.1%, respectively). CONCLUSIONS: The results confirm previous suggestions of a stronger effect of particulate air pollution among people in low social class. Given the uneven geographical distributions of social deprivation and traffic emissions in Rome, the most likely explanation is a differential burden of chronic health conditions conferring a greater susceptibility to less advantaged people.     

A comparison of particulate matter from biomass-burning rural and non-biomass-burning urban households in northeastern China

BACKGROUND: Biomass fuel is the primary source of domestic fuel in much of rural China. Previous studies have not characterized particle exposure through time-activity diaries or personal monitoring in mainland China. OBJECTIVES: In this study we characterized indoor and personal particle exposure in six households in northeastern China (three urban, three rural) and explored differences by location, cooking status, activity, and fuel type. Rural homes used biomass. Urban homes used a combination of electricity and natural gas. METHODS: Stationary monitors measured hourly indoor particulate matter (PM) with an aerodynamic diameter < or = 10 microm (PM10) for rural and urban kitchens, urban sitting rooms, and outdoors. Personal monitors for PM with an aerodynamic diameter < or = 2.5 microm (PM2.5) were employed for 10 participants. Time-activity patterns in 30-min intervals were recorded by researchers for each participant. RESULTS: Stationary monitoring results indicate that rural kitchen PM10 levels are three times higher than those in urban kitchens during cooking. PM10 was 6.1 times higher during cooking periods than during noncooking periods for rural kitchens. Personal PM2.5 levels for rural cooks were 2.8-3.6 times higher than for all other participant categories. The highest PM2.5 exposures occurred during cooking periods for urban and rural cooks. However, rural cooks had 5.4 times higher PM2.5 levels during cooking than did urban cooks. Rural cooks spent 2.5 times more hours per day cooking than did their urban counterparts. CONCLUSIONS: These findings indicate that biomass burning for cooking contributes substantially to indoor particulate levels and that this exposure is particularly elevated for cooks. Second-by-second personal PM2.5 exposures revealed differences in exposures by population group and strong temporal heterogeneity that would be obscured by aggregate metrics.     

天津市可吸人颗粒物与城区居民每日死亡关系的时间序列分析

目的 研究天津市大气可吸入颗粒物(PM10)与城区居民每日死亡间的相关性.方法 通过收集天津市城区2005-2007年空气污染数据、日平均气温和相对湿度及每日死亡人数,采用广义相加模型,控制长期和季节趋势、气温和相对湿度等气象因素及二氧化硫(SO2)和二氧化氮(NO2)等气态污染物的影响,分析天津市PM10与居民每日死亡之间的关系.结果 大气PM10与人群每日非意外死亡、循环系统疾病死亡和呼吸系统疾病死亡间显著相关.PM10浓度每升高10 μg/m3,人群每日非意外死亡、循环系统疾病死亡和呼吸系统疾病死亡分别增加0.45%(0.21～0.69)、0.60%(0.29～0.91)和0.82%(0.04～1.61).结论 天津市大气PM10污染与城区居民每日死亡显著相关,尤其是循环系统疾病和呼吸系统疾病死亡.