Hydrocarbons in indoor air and their health-effects

Concentrations of harmful airborne substances are much higher in indoor air than outdoors. Furniture, cleansing agents, paints, solvents, carpets and floors release numerous volatile organic compounds (VOCs), which can only be reduced through adequate ventilation. The present investigation considered data of 463 participants in the fourth year of age within a project of the Helmholtz Centre for Environmental Research. 39 of them developed wheezing symptoms, 148 bronchitis and 397 infections. A novel model, based on logistic regression, was used to find associations between certain VOC concentrations and the outcome of airway diseases. The analysis involved gender, contact with cats, environmental tobacco smoke (ETS), and the prevalence of atopy in both parents. The aim was to find threshold concentrations of VOCs and to give recommendations for the abatement of environmentally caused diseases. The present research proved findings of other studies, for instance, that “wheezing ever” appeared when high concentrations of hexane, benzene, ethylbenzene, and chlorbenzene were reported. Such relationships were observed for “wheezing ever” in the past year. The number of wheezing participants was low (39) and, therefore, also some other airway diseases (infection, bronchitis and asthma) were tested for their relationship to VOC concentrations

Kürzestfristvorhersage der Windgeschwindigkeit in einem Wirbelschleppenwarnsystem für Flughäfen

Die lange Lebensdauer und die hohe Intensität der Wirbelschleppen landender Großraumflugzeuge kann zu einer Gefährdung des nachfolgenden Verkehrs führen. Zur Vorhersage einer gefährdungsfreien Nutzungszeit der Landebahn, nach der die Staffelungsabstände der landenden Flugzeuge bestimmt werden, dient ein Wirbelschleppenwarnsystem. Ein wesentlicher Teil dieses Warnsystems ist die Vorhersage des quer zur Landebahn wehenden Windes. Dafür wird bisher ein auf Persistenz beruhendes Verfahren eingesetzt. Die vorliegende Arbeit zeigt, daß durch Verwendung eines autoregressiven Modells die Querwindprognose verbessert werden kann. Dazu werden die Meßdaten analysiert und die Modellparameter geschätzt. Der Einsatz der AR Prognose im Wirbelschleppenwarnsystem führt im Vergleich zur bisherigen Methode zu längeren Nutzungszeiten und vermeidet das Auftreten von Diskontinuitäten (Sprüngen) in der Vorhersage. Besonders durch letzteres wird die Akzeptanz des Warnsystems bei den Fluglotsen verbessert

Measurement and modelling of the cumulated thermal stress in Leipzig

This paper shows first results of mobile measurements, which carried out in summer 2009 to evaluate the thermal comfort for a „standardized‟ pedestrian in several urban areas of Leipzig. The analysis of the obtained data was conducted by calculating the mean radiant temperature as well as the Predicted Mean Vote (PMV). The results were compared to simulations applying the RayMan-program. Additionally to these findings to short-term stress, a study to the cumulated thermal stress was implemented into the analysis for the first time. Thereby, the thermal stress was considered which is perceived by a healthy ‟standardized‟ person during a one hour walk. As a first step a time rate of change of the PMV was defined for a measurement period. Using the example of the 20th August, 2009 in Leipzig, urban district Lößnig, a cumulated PMVaggregation of 0.7 was calculated and hence, a total (cumulated) PMV of 3.4 results in comparison to an arithmetically averaged PMV of only 2.7 for all measurement points along the route that were taken that day. Thus, a person perceives a severe thermal stress when walking the typical pedestrian route in Leipzig-Lößnig in one hour

Relationship between sources and patterns of VOCs in indoor air

AbstractPeople spend most of their daytime in indoor environments. Their activities influence the composition of the indoor air by emitting volatile organic compounds (VOCs). The increasing number of different VOCs became the focus of attention in recent years as the question arises from the relationship between exposure to air pollutants and diseases. The present study of flats in Leipzig (Germany) is based on measurements of 60 different VOCs and is unique in the field of indoor air quality due to its enormous size of samples (n=2 242) and questionnaire data. The main purpose of our analysis was to identify the sources and patterns that characterize airborne VOCs in occupied flats. We combined two methods, principal components analysis (PCA) and non–negative matrix factorization (NMF), to assign compounds to their origin and to understand the coinstantaneous existence of several VOCs. PCA clustering provided a source apportionment and yielded 10 principal components (PCs) with an explained variance of 72%. However, real indoor air quality is often affected by combined sources. NMF reveals characteristic compositions of VOCs in indoor environments and emphasizes that constantly recurring structures are not single sources, but rather fusions of them, so called patterns. Interpreting these sources, we realized that homes were strongly influenced by ventilation, human activities, furnishings, natural processes (such as solar radiation) or their combinations. The very large set of samples and the combination with questionnaires applied on this comprehensive assessment of VOCs allows generalizing the results to homes in middle–scale cities with minor industrial pollution. As a conclusion, single VOC–dose–response relationships are inopportune for situations when indoor sources occur in combination. Further studies are necessary to assess associated health risks

Spatial Distribution of PM\u3csub\u3e2.5\u3c/sub\u3e-Related Premature Mortality in China

PM2.5 is a major component of air pollution in China and has a serious threat to public health. It is very important to quantify spatial characteristics of the health effects caused by outdoor PM2.5 exposure. This study analyzed the spatial distribution of PM2.5 concentration (45.9 μg/m3 national average in 2016) and premature mortality attributed to PM2.5 in cities at the prefectural level and above in China in 2016. Using the Global Exposure Mortality Model (GEMM), the total premature mortality in China was estimated to be 1.55 million persons, and the per capita mortality was 11.2 per 10,000 persons in the year 2016, resulting in higher estimates compared to the integrated exposure-response model. We assessed the premature mortality attributed to PM2.5 through common diseases, including ischemic heart disease (IHD), cerebrovascular disease (CEV), chronic obstructive pulmonary disease (COPD), lung cancer (LC), and lower respiratory infections (LRI). The premature mortality due to IHD and CEV accounted for 68.5% of the total mortality, and the per capita mortality (per 10,000 persons) for all ages due to IHD was 3.86, the highest among diseases. For the spatial distribution of disease-specific premature mortality, the top two highest absolute numbers of premature mortality associated with IHD, CEV, LC, and LRI, respectively, were found in Chongqing and Beijing. In 338 cities of China, we have found a significant positive spatial autocorrelation of per capita premature mortality, indicating the necessity of coordinated regional governance for an efficient control of PM2.5. Plain Language Summary Fine particulate matter (PM2.5) concentrations have increased in general, in most developing countries in recent decades. In China, PM2.5 pollution has become a major component of air pollution and has serious health impacts. To obtain a comprehensive understanding of the national health impacts of PM2.5 in China, we have used the Global Exposure Mortality Model (GEMM) to estimate the premature mortality associated with PM2.5 exposure in 338 cities in China at the prefectural level and above. In addition, we analyzed the spatial distribution of premature mortality attributed to PM2.5 for five diseases, including ischemic heart disease (IHD), cerebrovascular disease (CEV), chronic obstructive pulmonary disease (COPD), lung cancer (LC), and lower respiratory infections (LRI). Our study finds that the total premature mortality associated with PM2.5 exposure in China for 2016 was 1.55 million persons. The top two highest absolute numbers of premature mortality associated with IHD, CEV, LC, and LRI, respectively were found in Chongqing and Beijing. Furthermore, cities with high per capita premature mortality tended to be spatially connected with other cities with high per capita premature mortality, indicating the coordinated regional governance should be adopted to reduce the impact of PM2.5 on human health

Lässt sich die Aerosolbelastung von Stadtgebieten aus Satellitenbildern ableiten?

The use of contrast reducing Mie scattering for the derivation of aerosol optical thickness (AOT) of the atmosphere is described in this article. With the aid of Differential Texture Analysis (DTA) the contrast between two visual satellite images will be determined and the AOT will be deduced. An assessment of the DTA algorithm with Landsat 5 TM satellite images for the Munich area is presented here. Problems like false AOT values caused by surface albedo changes and uncertainties in pollution loading are discussed, and proposed solutions will also be presented. Two methods for solving these difficulties, the histogram method and the regression method, will be displayed.Zur Ableitung der Aerosol optischen Dicke (AOT) der Atmosphäre erweist sich die kontrastreduzierende Wirkung der Mie-Streuung an Aerosolpartikeln als nützlich. Zwischen zwei unterschiedlich belasteten visuellen Satellitenbildern wird mit Hilfe der Differentiellen Texturanalyse (DTA) der Kontrastunterschied beider berechnet und daraus die AOT abgeleitet. In dieser Arbeit geht es um die Bewertung des DTA-Algorithmus' anhand von Landsat 5 TM Satellitenbildern vom Großraum München. Im Folgenden werden auch Probleme des DTA-Codes, wie z.B. falsch detektierte AOT auf Grund von Änderungen der Bodenalbedo und zu niedrig ermittelte AOT-Werte bedingt durch Ungereimtheiten der Belastungssituationen der Satellitenbilder, diskutiert und Lösungsvorschläge, u.a. die Histogramm- und Regressionsmethode, präsentiert

Spatiotemporal Variations of City-Level Carbon Emissions in China during 2000–2017 Using Nighttime Light Data

China is one of the largest carbon emitting countries in the world. Numerous strategies have been considered by the Chinese government to mitigate carbon emissions in recent years. Accurate and timely estimation of spatiotemporal variations of city-level carbon emissions is of vital importance for planning of low-carbon strategies. For an assessment of the spatiotemporal variations of city-level carbon emissions in China during the periods 2000–2017, we used nighttime light data as a proxy from two sources: Defense Meteorological Satellite Program’s Operational Linescan System (DMSP-OLS) data and the Suomi National Polar-orbiting Partnership satellite’s Visible Infrared Imaging Radiometer Suite (NPP-VIIRS). The results show that cities with low carbon emissions are located in the western and central parts of China. In contrast, cities with high carbon emissions are mainly located in the Beijing-Tianjin-Hebei region (BTH) and Yangtze River Delta (YRD). Half of the cities of China have been making eorts to reduce carbon emissions since 2012, and regional disparities among cities are steadily decreasing. Two clusters of high-emission cities located in the BTH and YRD followed two dierent paths of carbon emissions owing to the diverse political status and pillar industries. We conclude that carbon emissions in China have undergone a transformation to decline, but a very slow balancing between the spatial pattern of high-emission versus low-emission regions in China can be presumed

Spatial Distribution of PM\u3csub\u3e2.5\u3c/sub\u3e-Related Premature Mortality in China

PM2.5 is a major component of air pollution in China and has a serious threat to public health. It is very important to quantify spatial characteristics of the health effects caused by outdoor PM2.5 exposure. This study analyzed the spatial distribution of PM2.5 concentration (45.9 μg/m3 national average in 2016) and premature mortality attributed to PM2.5 in cities at the prefectural level and above in China in 2016. Using the Global Exposure Mortality Model (GEMM), the total premature mortality in China was estimated to be 1.55 million persons, and the per capita mortality was 11.2 per 10,000 persons in the year 2016, resulting in higher estimates compared to the integrated exposure-response model. We assessed the premature mortality attributed to PM2.5 through common diseases, including ischemic heart disease (IHD), cerebrovascular disease (CEV), chronic obstructive pulmonary disease (COPD), lung cancer (LC), and lower respiratory infections (LRI). The premature mortality due to IHD and CEV accounted for 68.5% of the total mortality, and the per capita mortality (per 10,000 persons) for all ages due to IHD was 3.86, the highest among diseases. For the spatial distribution of disease-specific premature mortality, the top two highest absolute numbers of premature mortality associated with IHD, CEV, LC, and LRI, respectively, were found in Chongqing and Beijing. In 338 cities of China, we have found a significant positive spatial autocorrelation of per capita premature mortality, indicating the necessity of coordinated regional governance for an efficient control of PM2.5. Plain Language Summary Fine particulate matter (PM2.5) concentrations have increased in general, in most developing countries in recent decades. In China, PM2.5 pollution has become a major component of air pollution and has serious health impacts. To obtain a comprehensive understanding of the national health impacts of PM2.5 in China, we have used the Global Exposure Mortality Model (GEMM) to estimate the premature mortality associated with PM2.5 exposure in 338 cities in China at the prefectural level and above. In addition, we analyzed the spatial distribution of premature mortality attributed to PM2.5 for five diseases, including ischemic heart disease (IHD), cerebrovascular disease (CEV), chronic obstructive pulmonary disease (COPD), lung cancer (LC), and lower respiratory infections (LRI). Our study finds that the total premature mortality associated with PM2.5 exposure in China for 2016 was 1.55 million persons. The top two highest absolute numbers of premature mortality associated with IHD, CEV, LC, and LRI, respectively were found in Chongqing and Beijing. Furthermore, cities with high per capita premature mortality tended to be spatially connected with other cities with high per capita premature mortality, indicating the coordinated regional governance should be adopted to reduce the impact of PM2.5 on human health

Impacts of Personalized Sensor Feedback Regarding Exposure to Environmental Stressors

Feedback on personal exposure to air pollution, noise or extreme temperatures through wearable sensors or sensors installed at home or in the workplace can offer information that might motivate behaviours to mitigate exposure. As personal measurement devices are becoming increasingly accessible, it is important to evaluate the effects of such sensors on human perception and behaviour. We conducted a systematic literature research and identified 33 studies, analysing the effects of personal feedback on air pollution, noise and temperatures. Feedback was given through reports including different forms of visualization, in-person or over the telephone, or directly on the sensor or through a phone app. The exposure feedback led to behaviour changes particularly for noise and temperature feedback while findings on behaviour adaptation to avoid air pollution were mixed. Most studies reported increased awareness and knowledge from receiving exposure feedback. Many participants in studies on air pollution reported low levels of self-efficacy regarding exposure mitigation. For a better understanding of the effects of personal exposure feedback, more studies are required, particularly providing feedback from wearable sensors measuring outdoor air pollution, noise and temperature