Motivated by public interest, the Clean Air and Urban Landscapes (CAUL) hub deployed instrumentation to measure air quality at a roadside location in Sydney. The main aim was to compare concentrations of fine particulate matter (PM2.5) measured along a busy road section with ambient regional urban background levels, as measured at nearby regulatory air quality stations. The study also explored spatial and temporal variations in the observed PM2.5 concentrations. The chosen area was Randwick in Sydney, because it was also the subject area for an agent-based traffic model. Over a four-day campaign in February 2017, continuous measurements of PM2.5 were made along and around the main road. In addition, a traffic counting application was used to gather data for evaluation of the agent-based traffic model. The average hourly PM2.5 concentration was 13 µg/m3, which is approximately twice the concentrations at the nearby regulatory air quality network sites measured over the same period. Roadside concentrations of PM2.5 were about 50% higher in the morning rush-hour than the afternoon rush hour, and slightly lower (reductions of <30%) 50 m away from the main road, on cross-roads. The traffic model under-estimated vehicle numbers by about 4 fold, and failed to replicate the temporal variations in traffic flow, which we assume was due to an influx of traffic from outside the study region dominating traffic patterns. Our findings suggest that those working for long hours outdoors at busy roadside locations are at greater risk of suffering detrimental health effects associated with higher levels of exposure to PM2.5. Furthermore, the worse air quality in the morning rush hour means that, where possible, joggers and cyclists should avoid busy roads around these times.
Fine particulate matter (PM2.5; ≤2.5 μm in aerodynamic diameter) stands out among all pollutants as more directly responsible for long-term health problems. This work aims to evaluate the public health benefits of improved air quality in Brazil, based on the estimated reduction in mortality from PM2.5, a pollutant commonly related to all causes mortality including non-accidental, cardiovascular, ischemic heart diseases and lung cancer. Annual PM2.5 concentrations were obtained from 50 monitoring stations spread across 24 Brazilian cities between the years 2000 and 2017, which constituted the baseline scenario. The control scenario was represented by the annual PM2.5 guideline values (10 μg m−3) of the World Health Organization (WHO). The relationship between the change in baseline and control scenarios with health effects was estimated using the BenMAP-CE program and the application of exposure-response functions. São Paulo city showed the highest number of avoidable deaths, with values ranging from 28,874 ± 9769 and 82,720 ± 24,549 for all causes from 2000 to 2017. In 2009, just three Brazilian cities were monitoring PM2.5. Between 877 ± 295 and 2497 ± 719 all causes avoidable deaths related to PM2.5 were estimated under the scenario when the WHO guideline was applied. In 2017, the 15 cities with representative annual PM2.5 data account for between 2378 ± 801 and 6282 ± 1818 avoidable deaths due to all-cause PM2.5 mortality, between 2974 ± 376 and 10,397 ± 516 avoidable deaths due non-accidental causes, between 1373 ± 230 and 3428 ± 265 avoidable deaths due cardiovascular disease, between 927 ± 162 and 2514 ± 156 avoidable deaths due ischemic heart diseases and the lowest between 101 ± 45 and 264 ± 88 avoidable deaths due to lung cancer.
Air pollution imposes serious health risks to urban populations and currently is the major environmental threat to the public health worldwide. In this context, discrimination and tracing of pollutants in atmosphere is a great challenge nowadays. This study reports the simultaneous use of Pb, Cu and Zn Multi-Isotopic Systems (MIS) to identify and discriminate pollutant sources of atmospheric particulate matter (PM) collected in day and nighttime temporal resolution in São Paulo city, Brazil. The isotopic fingerprints of road dust and tires (δ66Zn = 0.00 to +0.20‰ and 206Pb/207Pb = 1.16 to 1.19) were differentiated from vehicular traffic (δ66Zn = −0.60 to +0.00‰ and 206Pb/207Pb < 1.19) and PM from an industrial area (δ66Zn < −0.60‰ and 206Pb/207Pb > 1.20). Isotopic signatures of cement (δ66Zn = 0.00 to +0.30‰ and δ65CuNIST = +0.30 to +0.61‰) were distinguished from road dust (δ65Cu = +0.08 to +0.25‰) and vehicular traffic (δ65CuNIST = +0.46 to +0.59‰). The isotopic compositions found in PM for Pb (206Pb/207Pb = 1.156 to 1.312, n = 113), Zn (δ66Zn = +0.43 to −1.36‰, n = 62) and Cu (δ65Cu = +0.12 to 0.66‰, n = 7) are comparable with those measured on the main pollutant sources found in urban areas. Zinc and lead isotopic compositions of PM from Sao Paulo showed diurnal variations indicating the industrial contributions carried by cold fronts and road dust suspension associated to high wind speeds and traffic pattern. A ternary mixing model based on Pb and Zn isotopic fingerprints of the main pollutant sources were developed to account vehicular traffic (70%), industrial area (10%) and another uncharacterized source (20%) contributions, possibly associated with industrial and biomass burning emissions. Our findings validate the use of Pb, Cu and Zn MIS to source apportionment studies in the atmosphere with multiple and complex pollutant sources. https://www.sciencedirect.com/science/article/pii/S004896971830233X
The biogenic aerosol contribution to atmospheric particulate matter (PM) mass concentration is usually neglected due to the difficulty in identifying its components, although it can be significant. In the Metropolitan Area of São Paulo (MASP)-Brazil, several studies have been performed to identify sources for PM, revealing vehicular emissions and soil re-suspension as the main identified sources. The organic fraction has been related primarily to biomass burning (BB) and fuel combustion, although there is significant presence of green areas in the city which render biogenic emissions as an additional source of organic carbon (OC). The objectives of this work are to (i) estimate the relative mass contribution of fungal spores to PM concentrations with sizes smaller than 10µm (PM10) in MASP, (ii) assess the main sources of PM10, and (iii) characterise the composition of the PM10. To achieve these objectives, we measured markers of biogenic sources and BB, during the fall-winter transition, which along with other constituents, such as ions, organic/elemental carbon, elemental composition and fungal spore concentrations, help assess the PM10 sources. We used receptor models to identify distinct source-related PM10 fractions and conversion factors to convert biomarker concentrations to fungal mass. Our results show the mean contributions of fungal aerosol to PM10 and OC mass were 2% and 8%, respectively, indicating the importance of fungal spores to the aerosol burden in the urban atmosphere. Using specific rotation factor analysis, we identified the following factors contributing to PM: soil re-suspension, biogenic aerosol, secondary inorganic aerosol, vehicular emissions and BB/isoprene-related secondary organic aerosol (I-SOA) markers. BB/I-SOA markers are the main source representing 28% of the PM10 mass, while biogenic aerosol explained a significant (11%) fraction of the PM10 mass as well. Our findings suggest that primary biogenic aerosol is an important fraction of PM10 mass, yet not considered in most studies.
São Paulo in Brazil has relatively relaxed regulations for ambient air pollution standards and often experiences high air pollution levels due to emissions of particulate pollutants from local sources and long-range transport of biomass burning-impacted air masses. In order to evaluate the sources of particulate air pollution and related health risks, a year-round sampling was done at the University of São Paulo campus (20 m above ground level), a green area near an important expressway. The sampling was performed for PM2.5 (≤ 2.5 μm) and PM10 (≤ 10 μm) in 2014 through intensive (every day sampling in wintertime) and extensive campaigns (once a week for the whole year) with 24 h of sampling. This year was 25 characterized to have lower average precipitation comparing to meteorological data, and high pollution episodes were observed all year round, with a significant increase of pollution level in the intensive campaign, which was performed during wintertime. Different chemical constituents, such as carbonaceous species, polycyclic aromatic hydrocarbons (PAHs) and derivatives, water-soluble ions and biomass burning tracers were identified in order to evaluate health risks and to apportion sources. The species such as PAHs, inorganic and organic ions and monosaccharides were determined by chromatographic techniques and carbonaceous species by thermal-optical analysis. Trace elements were determined by inductively coupled plasma mass spectrometry. The associated risks to particulate matter exposure based on PAH concentrations were also assessed, along with indexes such as the benzo[a]pyrene equivalent (BaPE) and lung cancer risk (LCR). High BaPE and LCR were observed in most of the samples, rising to critical values in the wintertime. Also, biomass burning tracers and PAHs were higher in this season, while secondarily formed ions presented low variation throughout the year. Meanwhile, 35 vehicular tracer species were also higher in the intensive campaign suggesting the influence of lower dispersion conditions in that period. Source apportionment was done by Positive Matrix Factorization (PMF), which indicated five different factors: road dust, industrial emissions, vehicular exhaust, biomass burning and secondary processes. The results highlighted the contribution of vehicular emissions and the significant input from biomass combustion in wintertime, suggesting that most of the particulate matter is due to local sources, besides the influence of pre-harvest sugarcane burning.
We present a comprehensive review of published results from the last 30 years regarding the sources and atmospheric characteristics of particles and ozone in the Metropolitan Area of São Paulo (MASP). During the last 30 years, many efforts have been made to describe the emissions sources and to analyse the primary and secondary formation of pollutants under a process of increasing urbanisation in the metropolitan area. From the occurrence of frequent violations of air quality standards in the 1970s and 1980s (due to the uncontrolled air pollution sources) to a substantial decrease in the concentrations of the primary pollutants, many regulations have been imposed and enforced, although those concentrations do not yet conform to the World Health Organization guidelines. The greatest challenge currently faced by the São Paulo State Environmental Protection Agency and the local community is controlling secondary pollutants such as ozone and fine particles. Understanding the formation of these secondary pollutants, by experimental or modelling approaches, requires the description of the atmospheric chemical processes driven by biofuel, ethanol and biodiesel emissions. Exposure to air pollution is the cause of many injuries to human health, according to many studies performed not only in the region but also worldwide, and affects susceptible populations such as children and the elderly. The MASP is the biggest megacity in the Southern Hemisphere, and its specifics are important for other urban areas that are facing the challenge of intensive growth that puts pressure on natural resources and worsens the living conditions in urban areas. This text discusses how imposing regulations on air quality and emission sources, mainly related to the transportation sector, has affected the evolution of pollutant concentrations in the MASP.
We critically assessed numerous aspects such as vehicle fleet, type of fuel used in road vehicles, their emissions and concentrations of particulate matter ≤2.5 µm (PM2.5) and ≤10 µm (PM10) in three of the most polluted metropolitan areas of Brazil: the Metropolitan areas of São Paulo (MASP), Rio de Janeiro (MARJ) and Belo Horizonte (MABH). About 90% of the Brazilian LDVs run on ethanol or gasohol. The HDVs form a relatively low fraction of the total fleet but account for 90% of the PM from road vehicles. Brazilian LDVs normally emit 0.0011g (PM) km-1 but HDVs can surpass 0.0120g (PM) km-1. The emission control programs (e.g., PROCONVE) have been successful in reducing the vehicular exhaust emissions, but the non-exhaust vehicular sources such, as evaporative losses during refueling of vehicles as well as wear from the tyre, break, and road surface have increased in line with the increase in the vehicle fleet. The national inventories show the highest annual mean PM2.5 (28.1μg m–3) in the MASP that has the largest vehicle fleet in the country. In general, the PM10 concentrations in the studied metropolitan areas appear to comply with the national regulations but were up to ~3-times above the WHO guidelines. The current Brazilian air quality standards are far behind the European standards. There has been a progress in bringing more restrictive regulations for air pollutants including PM10 and PM2.5 but such steps also require suitable solutions to control PM emissions from motor vehicles and mechanical processes.
Household air pollution is ranked the 9th largest Global Burden of Disease risk (Forouzanfar et al., The Lancet 2015). People, particularly urban dwellers, typically spend over 90% of their daily time indoors, where levels of air pollution often surpass those of outdoor environments. Indoor air quality (IAQ) standards and approaches for assessment and control of indoor air require measurements of pollutant concentrations and thermal comfort using conventional instruments. However, the outcomes of such measurements are usually averages over long integrated time periods, which become available after the exposure has already occurred. Moreover, conventional monitoring is generally incapable of addressing temporal and spatial heterogeneity of indoor air pollution, or providing information on peak exposures that occur when specific indoor sources are in operation. This article provides a review of the new air pollution sensing methods to determine IAQ and discusses how real-time sensing could bring a paradigm shift in controlling the concentration of key air pollutants in billions of urban houses worldwide. However, we also show that besides the opportunities, challenges still remain in terms of maturing technologies, or data mining and their interpretation. Moreover, we discuss further research and essential development needed to close gaps between what is available today and needed tomorrow. In particular, we demonstrate that awareness of IAQ risks and availability of appropriate regulation are lagging behind the technologies.
Suspended particles of different sizes, shapes and composition are an integral part of the air that we breathe. Aerosol particles smaller than 100. nm in diameter are known as ultrafine particles (UFPs). Recent toxicological and epidemiological studies have raised the hypothesis that UFPs have a greater potential to affect public health compared with their larger counterparts. The rationale is that they are so small in size that they can penetrate deep into the lungs and translocate to different part of human body. Because of their small size, however, their contribution to total particle mass concentrations remains hardly detectable. Therefore, UFPs are preferentially measured as particle number concentrations. During the past decade there have been significant advances in the area of identifying sources, measurements and physicochemical characterisation of UFPs. Yet, their progress has not reached a juncture where the ambient air quality standards for UFPs could be set. The overall goal of this chapter is to provide a comprehensive overview of topics related to UFP measurements and their associated pollution issues. While there has been a significant progress in the measurement methods and availability of instruments to reliably monitor, these instruments are still expensive and their standard calibration methods are yet to take place. The process of standardisation and development of measurement infrastructure are needed to bring regulatory guidelines for airborne UFPs in future.