Levels and drivers of urban black carbon and health risk assessment during pre- and COVID19 lockdown in Augsburg, Germany.

This study aimed to evaluate the levels and phenomenology of equivalent black carbon (eBC) at the city center of Augsburg, Germany (01/2018 to 12/2020). Furthermore, the potential health risk of eBC based on equivalent numbers of passively smoked cigarettes (PSC) was also evaluated, with special emphasis on the impact caused by the COVID19 lockdown restriction measures. As it could be expected, peak concentrations of eBC were commonly recorded in morning (06:00-8:00 LT) and night (19:00-22:00 LT) in all seasons, coinciding with traffic rush hours and atmospheric stagnation. The variability of eBC was highly influenced by diurnal variations in traffic and meteorology (air temperature (T), mixing-layer height (MLH), wind speed (WS)) across days and seasons. Furthermore, a marked "weekend effect" was evidenced, with an average eBC decrease of ∼35% due to lower traffic flow. During the COVID19 lockdown period, an average ∼60% reduction of the traffic flow resulted in ∼30% eBC decrease, as the health risks of eBC exposure was markedly reduced during this period. The implementation of a multilinear regression analysis allowed to explain for 53% of the variability in measured eBC, indicating that the several factors (e.g., traffic and meteorology) may contribute simultaneously to this proportion. Overall, this study will provide valuable input to the policy makers to mitigate eBC pollutant and its adverse effect on environment and human health.

Spatial hazard assessment of the PM10 using machine learning models in Barcelona, Spain.

Air pollution, and especially atmospheric particulate matter (PM), has a profound impact on human mortality and morbidity, environment, and ecological system. Accordingly, it is very relevant predicting air quality. Although the application of the machine learning (ML) models for predicting air quality parameters, such as PM concentrations, has been evaluated in previous studies, those on the spatial hazard modeling of them are very limited. Due to the high potential of the ML models, the spatial modeling of PM can help managers to identify the pollution hotspots. Accordingly, this study aims at developing new ML models, such as Random Forest (RF), Bagged Classification and Regression Trees (Bagged CART), and Mixture Discriminate Analysis (MDA) for the hazard prediction of PM10 (particles with a diameter less than 10 µm) in the Barcelona Province, Spain. According to the annual PM10 concentration in 75 stations, the healthy and unhealthy locations are determined, and a ratio 70/30 (53/22 stations) is applied for calibrating and validating the ML models to predict the most hazardous areas for PM10. In order to identify the influential variables of PM modeling, the simulated annealing (SA) feature selection method is used. Seven features, among the thirteen features, are selected as critical features. According to the results, all the three-machine learning (ML) models achieve an excellent performance (Accuracy > 87% and precision > 86%). However, the Bagged CART and RF models have the same performance and higher than the MDA model. Spatial hazard maps predicted by the three models indicate that the high hazardous areas are located in the middle of the Barcelona Province more than in the Barcelona's Metropolitan Area.

Environmental impact and potential use of coal fly ash and sub-economical quarry fine aggregates in concrete.

The Israeli quarry industry produces 57 Mt of raw material and ∼4-6Mt of associated sub-economical by-products annually. These sub-economical quarry fines are not used because production and transportation costs considerably exceed their retail value. Therefore these by-products, are stored in large piles of fine grain size particles, create environmental risks to their surrondings. This paper evaluates the possibility of mixing the sub-economical quarry by-products of two Israeli quarries with sub-economical Class F coal fly ash (<20wt.% CaO) to form an economical aggregate sand substitute to be used as a concrete filler product. To study the feasibility of the aggregate as partial substitute to sand in concrete several analyses, including leaching experiements (EN12457-2), analytical techinques (SEM-EDX, ICP-MS, ICP-AES, and XRD), as well as an analysis of the mechanical and chemical properties of the concrete aggregate (strength, workability, and penetration) were performed. Scrubbing quarry waste with coal fly ash was found to be very effective for reducing the leaching rate of potentially harmful trace elements. In addition, adding fly ash with quarry fines as partial substitute to sand enhanced the performance of the concrete mixture and the properties of the fresh and harden concrete.

2005-2014 trends of PM10 source contributions in an industrialized area of southern Spain.

Particulate matter with a diameter of 10 µm or less (PM10) using receptor modelling was determined at an urban (La Linea, LL) and an industrial area (Puente Mayorga, PMY) in Southern Spain with samples collected during 2005-2014. The concentrations of PM10 had been decreasing at both sites in three distinctive periods: 1) the initial PM10 levels approached or exceeded the Spain and EU PM10 annual guidelines of 40 µg/m3 during 2005-2007 at LL and 2005-2009 at PMY; 2) then PM10 dropped by 25%-∼30 µg/m3 during 2008-2011 at LL and during 2010-2011 at PMY; 3) since 2012, the PM10 concentrations gradually decreased to <30 µg/m3. Chemical compositions of PM10 revealed the important contributions of water soluble ions (sulfate, nitrate, ammonium, and chloride), carbonaceous aerosols, and other major elements. These PM components generally showed a decrease trend, in accord with the trend of PM10 reduction. A PMF model identified seven sources to PM10 contributions. Secondary sulfate, soil/urban/construction dust, and secondary nitrate showed significantly decreasing trends with reduction of 40-60% comparing to the initial levels. The road traffic contribution decreased by 14% from the first to third period. However, sea salt, oil combustion, and industrial metallurgical process had relative stable contributions. These source contribution changes are reasonably governed by the PM emission abatement actions implemented during the past decade, as well as the financial crisis, that accounted for a significant decrease of PM pollution in Southern Spain. THE MAIN FINDING OF THE WORK: We identified that the mitigation efforts on industry, fossil fuel combustion, and urban transportation during the past decade were successful for air quality improvement in a highly industrialized area in Southern Spain.

Variability in exposure to ambient ultrafine particles in urban schools: Comparative assessment between Australia and Spain.

Ambient ultrafine particle number concentrations (PNC) have inhomogeneous spatio-temporal distributions and depend on a number of different urban factors, including background conditions and distant sources. This paper quantitatively compares exposure to ambient ultrafine particles at urban schools in two cities in developed countries, with high insolation climatic conditions, namely Brisbane (Australia) and Barcelona (Spain). The analysis used comprehensive indoor and outdoor air quality measurements at 25 schools in Brisbane and 39 schools in Barcelona. PNC modes were analysed with respect to ambient temperature, land use and urban characteristics, combined with the measured elemental carbon concentrations, NOx (Brisbane) and NO2 (Barcelona). The trends and modes of the quantified weekday average daily cycles of ambient PNC exhibited significant differences between the two cities. PNC increases were observed during traffic rush hours in both cases. However, the mid-day peak was dominant in Brisbane schools and had the highest contribution to total PNC for both indoors and outdoors. In Barcelona, the contribution from traffic was highest for ambient PNC, while the mid-day peak had a slightly higher contribution for indoor concentrations. Analysis of the relationships between PNC and land use characteristics in Barcelona schools showed a moderate correlation with the percentage of road network area and an anti-correlation with the percentage of green area. No statistically significant correlations were found for Brisbane. Overall, despite many similarities between the two cities, school-based exposure patterns were different. The main source of ambient PNC at schools was shown to be traffic in Barcelona and mid-day new particle formation in Brisbane. The mid-day PNC peak in Brisbane could have been driven by the combined effect of background and meteorological conditions, as well as other local/distant sources. The results have implications for urban development, especially in terms of air quality mitigation and management at schools.

Distribution and pollution assessment of trace elements in marine sediments in the Quintero Bay (Chile).

The aim of this study was to assess the levels of heavy metal pollution in the clay/silt fraction (<63 µm fraction) of marine sediments from Quintero Bay, Chile. For this, sediment samples were collected from 14 sites from the bay and analyzed for major and minor element determination. The metal concentrations found suggest an anthropogenic origin related with Cu, Se, Mo, As, Sb and Pb. The mineralogical characteristics of the samples were determined by XRD and selected samples were examined by SEM to determine morphological differences. The results showed heavy metal-bearing particles such as Cu, Zn, As and Pb, which are most likely associated with by the copper smelter.

Quantifying the health impacts of ambient air pollutants: recommendations of a WHO/Europe project.

OBJECTIVE: Quantitative estimates of air pollution health impacts have become an increasingly critical input to policy decisions. The WHO project "Health risks of air pollution in Europe--HRAPIE" was implemented to provide the evidence-based concentration-response functions for quantifying air pollution health impacts to support the 2013 revision of the air quality policy for the European Union (EU). METHODS: A group of experts convened by WHO Regional Office for Europe reviewed the accumulated primary research evidence together with some commissioned reviews and recommended concentration-response functions for air pollutant-health outcome pairs for which there was sufficient evidence for a causal association. RESULTS: The concentration-response functions link several indicators of mortality and morbidity with short- and long-term exposure to particulate matter, ozone and nitrogen dioxide. The project also provides guidance on the use of these functions and associated baseline health information in the cost-benefit analysis. CONCLUSIONS: The project results provide the scientific basis for formulating policy actions to improve air quality and thereby reduce the burden of disease associated with air pollution in Europe.

Assessment of personal exposure to particulate air pollution during commuting in European cities--recommendations and policy implications.

Commuting is considered as one of the high-exposure periods among various daily activities, especially in high vehicle-density metropolitan areas. There is a growing awareness of the need to change our transportation habits by reducing our use of cars and shifting instead to active transport, i.e. walking or cycling. A review was undertaken using the ISI web of knowledge database with the objective to better understand personal exposure during commuting by different modes of transport, and to suggest potential strategies to minimise exposure. The air pollutants studied include particulate matter, PM black carbon, BC and particle number concentration. We focused only in European studies in order to have comparable situation in terms of vehicle fleet and policy regulations applied. Studies on personal exposure to air pollutants during car commuting are more numerous than those dealing with other types of transport, and typically conclude by emphasising that travelling by car involves exposure to relatively high particulate matter, PM exposure concentrations. Thus, compared to other transport methods, travelling by car has been shown to involve exposure both to higher PM and BC as compared with cycling. Widespread dependence on private car transport has produced a significant daily health threat to the urban commuter. However, a forward-looking, integrated transport policy, involving the phased renovation of existing public vehicles and the withdrawal of the more polluting private vehicles, combined with incentives to use public transport and the encouragement of commuter physical exercise, would reduce commuters' exposure.

[Trends in environmental risks in the context of the economic crisis. SESPAS report 2014]. / Evolución de los riesgos ambientales en el contexto de la crisis económica. Informe SESPAS 2014.

This article aims to analyze the impact of the economic and financial crisis on environmental determinants of health. The World Health Organization estimates that between 13% and 27% of the disease burden in countries could be prevented by improving the environment. These effects are larger in vulnerable populations, especially among the poorest. In the last decade, outdoor air pollution (the most significant environmental health risk in most European countries) has declined, mostly due to the European policy of reducing emissions and to the decrease in activity following the economic crisis. During the last few years, this improvement in air quality has occurred simultaneously with a reduction in investment in environmental protection and could therefore be offset in the medium-term. The economic crisis has not reduced the trend for higher temperatures in Spain and Europe because climate change is a global phenomenon that is not directly related to local emissions. To reduce the risk of an increase in the health impact of environmental factors, certain key aspects should be considered, such as the need to maintain or develop adequate monitoring and control systems and the opportunity to implement policies that help improve the quality of the environment and reduce the vulnerability of different population groups in a cross-disciplinary framework of transparency and citizen participation.

Assessment of exposure to trace metals in a cohort of pregnant women from an urban center by urine analysis in the first and third trimesters of pregnancy.

Prenatal exposure to trace metals, whether they are essential, non-essential, or toxic, must be assessed for their potential health effects in the offspring. Herein is reported an approach to this end which involved collection of urine samples during the first and third trimesters of pregnancy from 489 mothers from Sabadell (Catalonia, Spain), a highly industrialized town. These samples were analyzed for cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), selenium (Se), arsenic (As), molybdenum (Mo), cadmium (Cd), antimonium (Sb), cesium (Cs), thallium (Tl), and lead (Pb). An acid digestion method was developed and validated for inductively coupled plasma quadruple mass spectrometry (Q-ICP-MS) analysis of these 12 metals. The median concentrations of metals ranged from 0.13 to 290 µg/g creatinine, the highest levels were found for Zn and the lowest for Th. The mean concentrations of most metals except As, Ni, Th, and Pb showed statistically significant differences between both trimesters. The concentrations of Mo, Se, Cd, Cs, and Sb were higher in the first than in the third trimester, whereas the opposite was found for Co, Cu, and Zn. The concentrations of all metals in both sampling periods showed statistically significant correlations (p<0.01 for Mo and Cu, p<0.001 for the others). The significant correlations of metal urine concentrations in the first and third trimesters of pregnancy suggest that the observed differences between both periods are related to physiological changes. Accordingly, the measured urine concentrations during either the first or third trimesters can be used as estimates of exposure during pregnancy and can serve as markers for prenatal intake of these metals in the studied cohort.

Identification of chemical tracers in the characterisation and source apportionment of inhalable inorganic airborne particles: an overview.

The acquisition of increasingly large analytical datasets from standardized air pollution monitoring stations allows more effective characterization of the fine aerosol cocktail breathed daily by modern urban populations. It is increasingly clear from such data that there is great variability in the chemical composition of inorganic inhalable particulate matter (PM10 = < 10 microm in size) in both space and time. Such variability can be demonstrated using selected tracer elements which, combined with source apportionment techniques, allow differentiation between natural (geological) and anthropogenic sources such as traffic and various industries. These tracer elements, which are commonly toxic metals, can be shown to concentrate in the finer, more deeply inhalable PM fraction, and are thus linked to potential inflammation and oxidative stress after inhalation. Legislation concerned only with measuring physical PM mass concentrations therefore fails to address potential health effects linked to chemical variations in ambient aerosols.