PM2.5暴露对儿童行为影响的系统综述

目的系统分析PM_2.5暴露对儿童行为的影响。方法以空气污染、细颗粒物、儿童、学生、儿童行为、神经行为、注意力、自闭症、孤独症谱系障碍、注意缺陷多动障碍、多动症、不良行为为中文关键词,以air pollution、fine particulate matter、particulate matter、PM2.5、children、student、behavior、autism、attention、inattention、neurobehavior、attention deficit hyperactivity disorder、ADHD、ASD为英文关键词,分别系统检索中国知网、万方数据知识服务平台和PubMed、Web of Science数据库发表的有关PM_2.5与儿童行为问题关联的相关文献。检索时段截至2019年11月,语种限定为中文和英文。纳入标准包括研究的暴露因素为PM2.5;研究结果包括行为障碍及相关疾病;纳入文献的语种为中文、英文;原创研究论文;病例对照、队列或横断面研究。排除标准包括动物实验;重复报告;综述类文章;研究暴露因素不包括PM_2.5;儿童自伤和违法等行为。最终纳入25篇文献。结果纳入的25篇文献中,12篇研究讨论PM_2.5暴露与儿童行为障碍疾病的关系,13篇探讨PM_2.5暴露与儿童异常行为之间的关系,基于中国人群的研究有5篇。根据研究设计分为出生队列研究(15个)、横断面研究(5个)、病例对照研究(5个),我国主要采用横断面研究和病例对照研究。研究结果提示,PM_2.5暴露会增加儿童行为问题的发生风险,既存在短期效应也存在长期效应。短期暴露于PM2.5易引起轻度的儿童异常行为,长期暴露可能加重儿童行为障碍疾病的发生风险。胎儿期和婴幼儿期可能是儿童行为问题发生的关键暴露窗口。结论PM_2.5暴露与儿童行为问题可能存在一定关联,在未来的研究中应开展纵向队列研究增强细颗粒物污染与儿童行为问题的因果关系论证。     

PM2.5暴露对儿童行为影响的文献分析

目的 系统化剖析细颗粒物(fine particulate matter,PM_2.5)暴露导致儿童行为问题的机理。方法 通过中英文关键字，分别系统化在各数据库开展搜索，收集PM_2.5暴露与儿童行为问题关联性的文献资料。通过文献资料纳入条件以及排除条件进行甄别筛选后，最后纳入24篇文献资料。结果 24篇文献资料中，分析PM_2.5暴露与儿童行为问题关联性的文献资料有14篇，分析PM_2.5暴露与儿童异常行为关联性的文献资料有10篇，以国内儿童当作研究对象的文献资料共3篇。根据研究分析设计分类，7篇病例对照研究，3篇横断面研究，14篇队列研究。研究结果表明，通过增大PM_2.5暴露浓度可以显著性增加儿童行为问题形成的风险性，而且PM_2.5暴露的时间周期越长，儿童行为问题也会显著性恶化发展。此外，研究表明儿童行为问题形成的关键时期是胎儿期以及婴幼儿期。结论 PM_2.5暴露浓度、时间对儿童行为影响巨大，可以促使儿童行为问题的形成与发展。     

代谢综合征组分异常人群PM2.5长期暴露与慢性肾脏疾病的关联

目的 探究细颗粒物(fine particulate matter, PM_2.5)长期暴露与代谢综合征(metabolism syndrome, MS)组分异常人群慢性肾脏疾病(chronic kidney disease, CKD)患病风险的关联。方法 基于北京市某医院健康体检数据,采用回顾性队列研究方法收集2013—2019年体检数据。问卷调查获取人口学特征和生活习惯信息,测量血压、身高、体重和腰围,检测甘油三酯(triglyceride, TG)、空腹血糖和高密度脂蛋白胆固醇(high density lipoprotein cholesterol, HDL-C)等。同时根据研究对象的地址提取经纬度进行污染物暴露数据的估计。利用Logistic回归模型分析PM_2.5长期暴露对MS组分异常人群CKD患病风险的估计效应。建立双污染物和多污染物模型,检验上述结果稳定性。基于年龄、是否患有MS、MS单组分异常情况及MS双组分异常情况进行相应的亚组分析。结果 研究共纳入1540名基线期MS组分异常人员,研究期间患CKD者206人,PM_2...     

2018—2019年保定市PM2.5质量浓度分布及其与气象因素相关性分析

目的分析保定市大气细颗粒物(PM_2.5)质量浓度分布及其与气象因素的关系。方法 2018—2019年每年1—12月,在保定市采集PM_2.5滤膜样品208张,同时记录环境温度、相对湿度以及大气压等实时气象数据,用重量分析法对PM_2.5的质量浓度进行分析,用离子色谱法对PM_2.5中Cl^-、NO₃^-、SO₄^2-、NH₄⁺4种水溶性无机离子进行分析,用Spearman秩相关性分析对大气PM_2.5与气象要素间的关系进行分析。结果 2019年保定市PM_2.5年平均质量浓度(73.1μg/m³)低于2018年(85.4μg/m³),且出现周期性规律即两年中月均PM_2.5质量浓度最高均出现在1月份最低均出现在8月份;2018年PM_2.5     

孕期大气细颗粒物PM2.5暴露及对早产的影响研究

目的 探讨空气中粒径≤2.5μm的颗粒物(PM_2.5)对早产的影响情况。方法 以受孕日期在2013年1月1日至12月31日之间、山西医科大学第一医院妇产科分娩的太原市区1882例产妇作为研究对象。按照WHO对早产的定义,将研究对象分为早产组和足月产组,关联性分析时再将早产组分为轻度早产组、早期早产和极早早产组。收集其一般人口学特征资料、健康状况、分娩情况、家庭准确住址等资料;收集太原市8个监测点2013年1月1日至2014年10月10日PM_2.5日平均浓度,根据反距离加权法计算孕妇孕期每天PM_2.5暴露浓度,通过多因素非条件logistic回归模型分析PM_2.5对早产的影响情况。结果 1839例产妇的早产发生率为8.21%(151/1839)。调整孕妇年龄、孕妇文化程度、孕前BMI等因素后结果显示,在分娩前第2周PM_2.5浓度暴露值每增加10μg/m³,早产风险增加8.7%(OR=1.087,95%CI:1.001~1.182),轻度早产风险增加9.9%(OR=1.099,95%CI:1.007~1.200)。分娩前第2周孕妇处于PM_2.5高水平环境(≥75μg/m³)中,早产风险增加0.8%(OR=1.008,95%CI:1.000~1.017),轻度早产风险增加1.0%(OR=1.010,95%CI:1.001~1.018)。结论 孕妇在孕晚期尤其是在分娩前半个月,PM_2.5高浓度暴露会导致早产风险增加。     

西安市大气PM2.5短期暴露对小学生肺功能的影响

目的 探讨西安市大气PM_2.5短期暴露对小学生肺功能的影响，为空气污染治理及保护儿童健康提供科学依据。方法 于2017年在西安市雁塔区(轻污染区)和莲湖区(重污染区)2个国家监测点内各选择1所小学(A校与B校)，采用整群随机抽样方法抽取三～五年级小学生，分别于采暖前后开展一次肺功能检测。同时收集检测当天及前29 d的PM_2.5日均浓度，采用多元线性回归分析PM_2.5暴露对小学生肺功能指数的影响。结果 2所小学采暖期PM_2.5的日均浓度分别为132.80μg/m³和110.00μg/m³，均超过二级浓度限值；采暖期PM_2.5的日均浓度均高于非采暖期(P<0.05)。在控制性别、年龄等影响因素后，PM_2.5暴露对B校学生肺功能指数FVC和FEV1的影响有统计学意义(P<0.05)，采暖期肺功能指数FVC相较于非采暖期平均降低0.080，肺功能指数FEV1平均降低0.056;PM_2.5...     

大气PM2.5长期暴露与肾功能的关联研究

目的 评估长期暴露于大气细颗粒物(fine particulate matter, PM_2.5)5种成分(黑炭、铵盐、硝酸盐、有机物、硫酸盐)对肾功能的长期效应。方法 基于中国健康与养老追踪调查(China Health and Retirement Longitudinal Study, CHARLS) 2011年和2015年的数据,纳入5 696名中老年人,使用贝叶斯核机器回归(Bayesian kernel machine regression, BKMR)方法探究黑炭、铵盐、硝酸盐、有机物和硫酸盐5种PM_2.5成分对肾功能的单独效应、交互效应和联合效应。结果 2011—2015年慢性肾脏病发生率为5.53%。有机物、黑炭、硝酸盐和硫酸盐的后验包含概率(posterior inclusion probabilities, PIP)值均为1.000,对估算肾小球滤过率(estimated glomerular filtration rate, eGFR)的影响较大。当其余4种变量固定在第25,50和75百分位时,有机物每增加1个四分位数间...     

北京秋季室内外PM2.5污染水平及其相关性

目的 了解北京市住宅室内空气颗粒物的污染状况,研究室外颗粒物以及室内活动对室内颗粒物浓度变化的影响,为制订和修订相应的室内空气质量标准提供基础数据及相应的科学依据.方法 于2008年10月27-31日对一社区居民住宅(8户)的室内和室外同步进行PM2.5的采集.采用称重法测得住宅室内外PM2.5的质量浓度,同时结合在线连续观测数据和时间活动模式问卷调查结果,了解各种污染源对室内外颗粒物浓度变化的影响.结果 采样期间的室内、室外平均浓度分别为58.5和74.1μg/m3,IO比值(室内与室外颗粒物质量浓度之比)为0.85.室内人为活动(做饭,打扫等)会使室内颗粒物浓度瞬间急剧增大,是室内主要的污染源之一;在夜间.室外颗粒物的渗透作用是影响室内环境的主要因素.结论 与国外相比,国内的室内PM2.5浓度仍处于-个较高的污染水平,做饭可能产生高浓度的颗粒物.室内环境应当受到公众的关注.     

PM2.5急性暴露对大鼠肺毒效应的研究

目的 采用气管滴注法对大鼠进行细颗粒物(fine particulate matter,PM_2.5)急性暴露，研究PM_2.5对不同性别大鼠的肺毒效应。方法 SPF级SD大鼠随机分为生理盐水对照组和PM_2.5高、中、低剂量组(PM_2.5粉末干重13.5、4.5和1.5 mg/kg)，气管滴注连续7 d后解剖，计算肺脏器系数；检测丙二醛(malondialdehyde,MDA)、超氧化物歧化酶(superoxide dismutases,SOD)、总蛋白(total protein,TP)和白蛋白(albumin,ALB)变化情况；苏木素-伊红(hematoxylin and eosin,HE)染色观察肺组织病理结构改变。结果 各组肺脏器系数均随着染毒剂量增加而升高，雌鼠高剂量组[(0.758±0.263)%]与对照组[(0.530±0.026)%]相比，雄鼠低剂量组[(0.476±0.049)%]与雌鼠[(0.565±0.057)%]相比，差异均有统计学意义(均P<0.05)；与对照组相比，雌鼠...     

深圳市南山区居民住宅区PM2.5污染状况及影响因素

目的了解深圳市南山区居民住宅区PM2.5污染情况,并分析其可能的影响因素。方法于2010年每月10—16日在深圳市南山区某教学楼楼顶进行PM2.5采样,同时收集采样当天的气象资料,并对PM2.5水平进行影响因素分析。结果 2010年共收集到83份有效滤膜,PM2.5平均浓度为0.050 mg/m3,日均浓度范围0.003～0.180 mg/m3;PM2.5浓度呈季节性波动,春、夏、秋、冬四季平均浓度分别为0.058、0.027、0.046、0.069 mg/m3,表现为夏秋季节浓度较低,而春冬季节浓度较高;PM2.5浓度受气温、相对湿度和降水情况等多种气象条件影响。PM2.5浓度与气温呈负相关(r=-0.820),与空气相对湿度呈负相关(r=-0.510),与降雨时大气中PM2.5浓度(0.038 mg/m3)相比,不降雨时大气中PM2.5浓度(0.064 mg/m3)较高(P<0.05)。结论南山区居民住宅区PM2.5污染较为严重(参考美国PM2.5卫生标准),气温、气湿和降雨均能影响大气中PM2.5水平,相关管理部门应重视PM2.5污染和健康危害。     

Modeling residential fine particulate matter infiltration for exposure assessment

Individuals spend the majority of their time indoors; therefore, estimating infiltration of outdoor-generated fine particulate matter (PM(2.5)) can help reduce exposure misclassification in epidemiological studies. As indoor measurements in individual homes are not feasible in large epidemiological studies, we evaluated the potential of using readily available data to predict infiltration of ambient PM(2.5) into residences. Indoor and outdoor light scattering measurements were collected for 84 homes in Seattle, Washington, USA, and Victoria, British Columbia, Canada, to estimate residential infiltration efficiencies. Meteorological variables and spatial property assessment data (SPAD), containing detailed housing characteristics for individual residences, were compiled for both study areas using a geographic information system. Multiple linear regression was used to construct models of infiltration based on these data. Heating (October to February) and non-heating (March to September) season accounted for 36% of the yearly variation in detached residential infiltration. Two SPAD housing characteristic variables, low building value, and heating with forced air, predicted 37% of the variation found between detached residential infiltration during the heating season. The final model, incorporating temperature and the two SPAD housing characteristic variables, with a seasonal interaction term, explained 54% of detached residential infiltration. Residences with low building values had higher infiltration efficiencies than other residences, which could lead to greater exposure gradients between low and high socioeconomic status individuals than previously identified using only ambient PM(2.5) concentrations. This modeling approach holds promise for incorporating infiltration efficiencies into large epidemiology studies, thereby reducing exposure misclassification.     

PM_(2.5)个体暴露连续监测方法

目的整合滤膜称重法和光散射法测定PM_(2.5)优越性,建立更加准确的PM_(2.5)个体暴露连续监测方法。方法采用滤膜称重法和光散射法同时测定个体PM_(2.5)暴露浓度,以滤膜称重法与光散法测定结果的比值作为校正系数,修正光散射法测定值,获得PM_(2.5)个体暴露实时浓度。结果测定时间为3、10、30和60 min时方法检出限(LOD)分别4.6、4.0、3.9和3.7μg/m~3;对不同浓度环境空气平行测定的精密度(RSD)范围为2.1%~9.5%;与微量振荡天平法(TEOM)测定的实时浓度(30min时间加权平均浓度)间具有良好的相关关系,Pearson r=0.934(P0.001,n=233),配对t检验结果表明两种方法结果间差异无统计学意义(P=0.957);实验室连续24 h监测中,30%(3/10)的监测检测到零点漂移,漂移值范围为-5~-3μg/m~3;连续5 d的现场监测中,7.5%(31/412)的监测检测到零点漂移,其中大部分的漂移值在-3~3μg/m~3,零点漂移方向和大小不受环境PM_(2.5)浓度影响。结论该方法结合了光散射法及重量法的优点,可以获得较为准确的PM_(2.5)个体实时暴露浓度,能够满足PM_(2.5)个体暴露监测的要求。     

Myocardial infarction deaths after high level exposure to particulate matter

STUDY OBJECTIVE: To examine the short term effects of raised concentrations of air pollutants on myocardial infarction deaths, the authors measured if incidence rate ratios increased after the concentration of suspended particulate matter (SPM) reached various critical values and were sustained for various periods of time. DESIGN: Retrospective analysis of a database, which contained hourly SPM concentrations and myocardial infarction deaths. METHODS: The rate of death (events/1000 hours) attributable to myocardial infarction was compared among SPM categories. SPM categories were classified by five different critical values that measured high SPM levels, and by the hours of exposure (exposure window) after reaching the critical SPM level. MAIN OUTCOME MEASURES: The adjusted incidence rate ratios in the various SPM categories were compared with the reference category (0-99 microg/m(3)) to determine the incidence rate ratio. SETTING: Tokyo Metropolitan area, Japan. Patients/ PARTICIPANTS: 14,950 people who died of myocardial infarction in the Tokyo Metropolitan area from 1990 to 1994. MAIN RESULTS: When the exposure window was one hour, the adjusted incidence rate ratio in each category were 1.13 (95% CI: 1.07 to 1.20) in the 100-149 microg/m(3) category, 1.17-1.24 in the intermediate categories, and 1.40 (1.00 to 1.97) in the highest (300 microg/m(3) over) category. When the exposure window was one to six hours, increased rate ratios were seen in the highest category (1.17 (four hours) to 1.40 (one hour)). Gradual increases in the incidence rate ratio were seen as the SPM category increased when the exposure window was less than six hours. CONCLUSION: An increased rate ratio of myocardial infarction deaths was seen within a few hours after reaching a high concentration of SPM. When the exposure window was less than six hours, there was a gradual increase in the incidence rate ratio as the SPM concentration increased.     

The use of improved exposure factors in the interpretation of fine particulate matter epidemiological results

Multi-city population-based epidemiological studies have consistently reported a significant association between ambient fine particulate matter (PM_2.5) concentrations and daily mortality. However, in these studies heterogeneity between-community effect estimates is often observed but not thoroughly examined, leaving much of the difference in the effects of individual communities inadequately explained. In this study, we evaluated whether community-specific exposure factors play a role in explaining heterogeneity in the associations between ambient PM_2.5 concentrations and several causes of mortality in 27 US communities from 1997 to 2002 as reported by Franklin et al. (J Expo Sci Environ Epidemiol 3:279–287, 2007). Using publically available databases, we created factors capturing home ventilation characteristics and commuting patterns. These factors include the normalized leakage, annual and seasonal temperatures, and in-vehicle commuting distances and time. In-vehicle commuting distance and time, and annual, spring, and fall temperatures were significant negative effect modifiers of the relationship between PM_2.5 exposure and respiratory and non-accidental mortality. Additionally, cardiovascular mortality PM_2.5 effect estimates were negatively modified by in-vehicle commuting distances. We concluded that future multi-community studies of particle health effects should consider these and other determinants of personal–ambient exposure relationships during the epidemiological analysis.     

Chemical analysis of World Trade Center fine particulate matter for use in toxicologic assessment

The catastrophic destruction of the World Trade Center (WTC) on 11 September 2001 caused the release of high levels of airborne pollutants into the local environment. To assess the toxicity of fine particulate matter [particulate matter with a mass median aerodynamic diameter < 2.5 microm (PM2.5)], which may adversely affect the health of workers and residents in the area, we collected fallen dust samples on 12 and 13 September 2001 from sites within a half-mile of Ground Zero. Samples of WTC dust were sieved, aerosolized, and size-separated, and the PM2.5 fraction was isolated on filters. Here we report the chemical and physical properties of PM2.5 derived from these samples and compare them with PM2.5 fractions of three reference materials that range in toxicity from relatively inert to acutely toxic (Mt. St. Helens PM; Washington, DC, ambient air PM; and residual oil fly ash). X-ray diffraction of very coarse sieved WTC PM (< 53 microm) identified calcium sulfate (gypsum) and calcium carbonate (calcite) as major components. Scanning electron microscopy confirmed that calcium-sulfur and calcium-carbon particles were also present in the WTC PM2.5 fraction. Analysis of WTC PM2.5 using X-ray fluorescence, neutron activation analysis, and inductively coupled plasma spectrometry showed high levels of calcium (range, 22-33%) and sulfur (37-43% as sulfate) and much lower levels of transition metals and other elements. Aqueous extracts of WTC PM2.5 were basic (pH range, 8.9-10.0) and had no evidence of significant bacterial contamination. Levels of carbon were relatively low, suggesting that combustion-derived particles did not form a significant fraction of these samples recovered in the immediate aftermath of the destruction of the towers. Because gypsum and calcite are known to cause irritation of the mucus membranes of the eyes and respiratory tract, inhalation of high doses of WTC PM2.5 could potentially cause toxic respiratory effects.     

Exposure to fine particulate matter (PM2.5) among highway toll station workers in taipei: direct and indirect exposure assessment

In this study, the authors assessed occupational exposure to PM2.5 among 47 highway toll station workers in Taipei, Taiwan. The subjects were monitored for 10 days to assess integrated 8-hr fine particulate matter (PM2.5) breathing zone concentration. Researchers constructed a microenvironment-time-concentration matrix and applied direct and indirect approaches to assess cumulative exposure. Mean PM2.5 concentration for workers in the truck and bus lanes was 308 microg/m3 (SD = 115.5 microg/m3), substantially higher compared with cash-payment car lanes (mean 115, SD = 41.8, p < 0.001) and ticket-payment car lanes (mean 109, SD = 48.7, p < 0.001). Concentration per vehicle in the truck and bus lanes was 6.4 and 3.7 times higher, respectively, than that of ticket- or cash-payment car lanes. Mean cumulative exposure for the 10-day period was 4,900-13,407 microg/m3.hr, with a mean of 8,019 microg/m3.hr (SD = 2,375.3). Indirect and direct concentrations were strongly correlated (r2 = .61, F(1,125); p = 0.000). The results of this study show that personal exposure to PM2.5 can be reliably estimated using indirect approaches.     

Chronic exposure to fine particulate matter emitted by traffic affects reproductive and fetal outcomes in mice

Air pollution is an important environmental health risk factor that can result in many different gestational and reproductive negative outcomes. In this study, we have investigated the effects of two different times of exposure (before conception and during pregnancy) to urban ambient particulate matter on reproductive and pregnancy outcomes in mice. Using exposure chambers receiving filtered (F) and non-filtered (NF) air, we observed that exposed females exhibited changes in the length of estrus cycle and extended estrus and, therefore, a reduction in the number of cycles during the studied period (F 2.6±0.22 and NF 1.2±0.29, p=0.03). The mean number of antral follicles declined by 36% (p=0.04) in NF mice (75±35.2) compared to F mice (118.6±18.4). Our results further indicate a significant increase in time necessary for mating and decreased fertility and pregnancy indices (p=0.003) in NF couples. Mean post-implantation loss rates were increased by 70% (p?0.005) in the NF2 group (exposed before and during pregnancy to NF air) compared to the F1 group (exposed before and during pregnancy to F air) and were influenced by both pre-gestational (p<0.004) and gestational (p<0.01) period exposure. Fetal weight was significantly higher in the F1 group when compared with the other groups (p<0.001), at a 20% higher weight in the F1 group (0.86±0.18 g) than in the NF2 group (0.68±0.10 g). Furthermore, fetal weight was influenced by both pre-gestational and gestational period exposure, and a significant interaction between these two factors was found (p<0.001). This study demonstrated that exposure to ambient levels of urban traffic-generated particulate matter negatively affects different functions and stages of the reproductive process. Our results also reinforce the idea that maternal exposure to air pollution is linked to negative pregnancy outcomes, even if the exposure occurs only before conception.     

The effect of imputation of exposure estimates on the association between fine particulate matter and mortality

PURPOSE: The Harvard Six Cities Study (HSCS) found a small but significant association between daily PM2.5 and daily mortality count. The HSCS findings have been used as the basis for new EPA regulations, requiring lower levels of PM2.5. We feel that there are unresolved issues regarding the HSCS that should be fully evaluated prior to its findings being used as the basis of new regulation, including how the extent and method of imputing exposure data affect the association with daily mortality counts.METHODS: We examined the association between PM2.5 levels and daily mortality count, comparing the results from the HSCS methods with results based on an alternate imputation method, and with non-missing data.RESULTS: Overall, approximately 30% of the data points used in the HSCS were imputed. The method of imputation affected the association between particulate matter and mortality to a substantial degree in most of the cities. When the model using the HSCS method was compared to the model using the alternate method, in two areas the coefficients decreased substantially and lost significance. In two areas they changed little; in one area it rose substantially and became significant; and in one area it declined substantially but remained significant. When compared to the model based on the non-missing data, somewhat different patterns were observed. In both comparisons there were some large changes in the magnitude of the effect, but these were not consistent with the model used.CONCLUSIONS: We are concerned about the degree of data imputation and the effect that the method of imputation has on the association between particulate matter levels and mortality. In the case of the HSCS it appears that the imputed data are more strongly associated with the outcome than other methods of imputation and than the non-missing data. The reasons for these observations are not readily apparent, but the differences in effect should be explored and explained.