Megacity of São Paulo, Brazil

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1 Air!!!!!! Quality Replace in São me Paulo, with the Brazil correct by Maria header de information Fátima Andrade!!!!!! The Evolution of Air Quality in the Megacity of São Paulo, Brazil A study of the growth of particulate matter and ozone concentrations with the rapid and intense urbanization of São Paulo, Brazil. Figure 1. Green pyramid of waste alternatives.

2 Numerous studies regarding the concentration of regulated pollutants, especially inhalable particulate matter (PM10) particulate matter with aerodynamic diameter less than 10 µm, also called inhalable particles have been conducted in the megacity of São Paulo during the past 40 years. 1,2 Although the population and the number of vehicles have increased considerably, the concentrations are now, on most days, meeting the national air quality standards for PM10, although not yet for PM2.5 particulate matter with aerodynamic diameter less than 2.5 µm, also called fine inhalable particles and ozone. 3 The stabilizing of PM10 concentrations is due, in large part, to the implementation of programs to control vehicle emissions, which have been in place since the 1980s, together with the effects of changing energy sources and users. In Brazil, 41 percent of all energy comes from renewable sources; the biggest share of renewable sources is from ethanol and sugarcane bagasse (41 percent), followed by hydropower (27.5 percent), and other renewable energy sources, including wood and charcoal (19.9 percent), biodiesel (2.5 percent), and wind (1.5 percent). Data are from The Metropolitan Area of São Paulo The Metropolitan Area of São Paulo (MASP) is the largest urban area in South America and is known for its cultural diversity. The rapid population growth in São Paulo from 1950 to 2000 was an example of intense urbanization, which represented a shift from rural to urban living; urban dwellers accounted for only 36 percent of the population in 1950, compared with 84 percent today. 5 The MASP is a good example not only for other metropolitan areas in Brazil, but also for urban settlements in developing countries throughout the world of the effects of disorganized growth and poor urban planning. The poor urban planning allowed the rapid occupation of the peripheral areas of the city by the working population, thus increasing the number of daily commuters. There are nearly 44 million commutes per day in the MASP: 37 percent by public transportation; 31 percent by passenger car; 31 percent by foot; and less than 1 percent by bicycle. 6 There are more than 8 million light- and heavy-duty vehicles (LDVs and HDVs, respectively) in the MASP, which makes vehicle emissions the main source of air pollutants. Brazil is characterized by large urban centers along the coast, the most populous cities being located in the southeastern region of the country: the greater metropolitan areas of São Paulo, Rio de Janeiro, and Belo Horizonte with 21, 13, and 5.7 million inhabitants, respectively. 5 According to the São Paulo State Environmental Protection Agency, road transportation accounts for 97 percent of carbon monoxide emissions, 85 percent of volatile organic compound emissions, 82 percent of nitrogen oxides emissions, 36 percent of sulfur dioxide emissions, and 36 percent of PM10 emissions. 3 Figure 1. Green areas represent sugarcane plantations in some of the states in southeastern Brazil. Notes: SP = São Paulo; PR = Parana; MG = Minas Gerais; RJ = Rio de Janeiro Source: CONAB (Companhia Nacional de Abastecimento) 9.

3 The HDV fleet is responsible for more than 50 percent of the PM2.5 concentration in the MASP, and more than 70 percent of the PM2.5 is organic or elemental carbon. 6 Air Pollution Sources In addition to vehicle emissions, numerous unregulated sources including evaporative emissions from gas stations; wood burning in bakeries, restaurants, and pizzerias; coal burning during outdoor grilling; and civil construction activities emit air pollutants in the MASP. 7 New studies have shown the importance of carbonaceous compounds to the composition of atmospheric aerosols. Oyama et al. 8 stated that primary biomass burning accounted for percent of all carbonaceous aerosols in the atmosphere of the MASP, 14.4 g kwh 1 in 1993 to 2.0 g kwh 1 in 2012 (PROCONVE phase P7), and PM10 emissions from HDVs decreased from 0.4 g kwh 1 in 1997 to 0.02 g kwh 1 in 2012 (PRO- CONVE phase P7). Figure 2 shows the mean annual concentrations of PM2.5 and PM10 measured at different air quality stations within the MASP operated by Companhia de Tecnologia de Saneamento Ambiental (Environmental Company of the State of São Paulo, CETESB) in relation to the limits established by the PROCONVE. For PM2.5, one downtown station was considered (Cerqueira Cesar, where data have been available since 2005), and for PM10, three downtown stations were considered (Cerqueira Cesar, Congonhas, and Ibirapuera). What makes the situation in Brazil unique is the large use of ethanol as a vehicular fuel. with sugarcane burning accounting for up to 15 percent of the organic carbon in the PM2.5 fraction. Figure 1 shows sugarcane cultivation in São Paulo. 9 Although regulations have been imposed to prohibit the pre-harvest burning of sugarcane bagasse, it still occurs in some areas during the harvest season (primarily September October). Local sources of emissions from biomass burning have been shown to account for no more than 3 percent of the PM2.5 emitted in the MASP. 7 Mitigating Pollution from Vehicular Emissions The highest pollutant concentrations were observed at the end of the 1980s and the beginning of the 1990s, when vehicle numbers began to grow and there were no emission controls. In 1986, the Programa de Controle de Emissões Veiculares (Program for the Control of Air Pollution Emissions by Motor Vehicles, PROCONVE) was implemented, establishing more restrictive emission limits in accordance with international standards. Each phase of the PROCONVE program was applied to new vehicles. PROCONVE was organized in six phases for LDVs (L1 L6) and seven phases for HDVs (P1 P7). Emissions of carbon monoxide from LDVs decreased from 24.0 g km 1 in 1989 to 1.3 g km 1 in 2013 (PROCONVE phase L6), while nitrogen oxides emissions from HDVs decreased from Despite the increase in the number of vehicles and in fuel consumption, pollutant concentrations have decreased in the past ten years, the only exceptions being those of ozone and PM Additional details concerning the impact of the PROCONVE are presented elsewhere. 10,11 Owing to frequent traffic jams, the number of motorcycles in the MASP has increased in recent years. Motorcycles are used by commuters, as well as for the speedy delivery of goods and documents, because they can pass between the lines of cars and trucks stuck in traffic. In recognition of the impact of motorcycle emissions on air pollution, a new program the Programa de Controle de Emissões de Motocicletas (Program for the Control of Air Pollution Emissions by Motorcycles, PROMOT) has imposed emission limits for motorcycles. The Use of Ethanol and Ozone Many countries have similar programs for controlling vehicular emissions. What makes the situation in Brazil unique is the large use of ethanol as a vehicular fuel. In 1975, the National Ethanol Program, known as Proálcool, was created to reduce dependence on petroleum imports, decrease emissions of carbon monoxide, and ban the use of lead as an anti-knock fuel additive. 12 In the beginning, the program required the use of 10-percent anhydrous ethanol as an additive to gasoline;

4 Figure 2. Concentration (in µg/m 3 ) of PM10 and PM2.5 and the evolution of emission factors from 1990 to 2016 in the Metropolitan Area of São Paulo, together with the evolution of the phases of PROCONVE for PM emissions by LDVs (Proconve-L) and HDVs (Proconve-P). Source: CETESB (Companhia de Tecnologia de Saneamento Ambiental) 3. however, more recently, the newly created modified Otto cycle engines have provided the option of using 100-percent hydrated ethanol. According to the National Petroleum Agency, 13 ethanol accounts for 19 percent of all vehicle fuel used in Brazil and 50 percent of the fuel used in the MASP. The large quantity of ethanol being used results in high concentrations of aldehydes and the formation of secondary pollutants via photochemical process, one such pollutant being ozone. Acetaldehyde emissions result from the incomplete combustion of ethanol. Uncertainties in the emissions inventory for mobile sources increase the difficulty of evaluating the real impact of the use of ethanol and its relative importance in comparison with gasohol (i.e., gasoline with 25-percent ethanol). Salvo and Geiger, 14 analyzing the concentrations of ozone and its precursors during periods characterized by greater consumption of ethanol or gasohol (depending on their respective, relative prices), suggested that ozone concentrations in the MASP can be reduced if the owners of flex-fuel cars switch from ethanol to gasohol. Other studies using air quality modeling have reached similar conclusions. 15 The number of days on which the air quality standard for ozone is exceeded decreased from 1996 to However, since 2006, there has been an increase in the number of days on which the maximum one-hour ozone limit is exceeded. There has also been a decrease in nitrogen oxides and carbon monoxide concentrations, despite the pronounced increase in fuel consumption. 10 One hypothesis to explain the increase in the number of days on which the maximum one-hour ozone limit is exceeded is that the participation of volatile organic compounds from evaporative emissions is increasing in the atmospheric photochemical process, simultaneous to a decrease in volatile organic compounds from exhaust emissions. Future Outlook Many questions are still under consideration. How can the atmospheric concentrations of fine particles and ozone be reduced? How can the standards recommended by the World Health Organization be achieved? How can evaporative emissions be reduced? Local projects and international collaborations (e.g., the University Global Partnership Network programs involving the University of São Paulo, North Carolina State University, and the University of Surrey, UK) have studied the role of the biomass burning in the formation of the aerosol and its impact on the radiative process. One thematic project involving the University of São Paulo, the University of Twente, Netherlands, and the University of Surrey is studying social justice, access to public transport, and air pollution, comparing the metropolitan areas of São Paulo, London, and Randstad. In addition, there are governmental programs to implement new regulations for the reduction of emissions from the transport sector and to improve public transportation, in order

5 to increase mobility and reduce commute times. However, these initiatives take too long to implement. Our recommendation is to invest in the programs that will have the greatest impact on air quality and consequently reduce the collateral health costs. Among these programs, we can mention: (a) the implementation of controlling the evaporative emissions during refueling, a short-term regulation that is cost-effective by allowing economic gain and diminishing the evaporative loss; (b) the use of cleaner energies in the city, which has a potential for solar energy, although this is a long-term regulation; and (c) the improvement of public transportation, making it more efficient and the scrapping of the old vehicles (more than 10 years old) that are responsible for most of the pollution emission. This last recommendation is only possible if there is an economical incentive for the owners of old cars, although it is a controversial proposal, it would be cost effective when considering the health impact of air pollution. Another important point that has to be addressed is to avoid regulatory loopholes that allow the old vehicles to return to the on-road fleet. In Brazil, the MASP is used as a reference for the implementation of programs addressing environmental and technological issues and can also be considered a laboratory for evaluating the impact of the large-scale use of biofuels (ethanol and biodiesel). em Maria de Fátima Andrade is an associate professor in the Atmospheric Sciences Department of the Institute of Astronomy, Geophysics, and Atmospheric Sciences (IAG), Universidade de São Paulo, Brazil. maria.andrade@iag.usp.br. References 1. Andrade, F.; Orsini, C.; Maenhhut, W. Relation between aerosol sources and meteorological parameters for inhalable atmospheric particles in Sao Paulo City, Brazil; Atmos. Environ. 1994, 28 (14), ; 2. Orsini, C.Q.; Tabacniks, M.H.; Artaxo, P.; Andrade, M.F.; Kerr, A.S. Characteristics of fine and coarse particles of natural and urban aerosols of Brazil; Atmos. Environ. - Part A General Topics 1986, 20 (11), ; 3. Relatório de qualidade do ar no Estado de São Paulo 2015 (Report of air quality in the São Paulo State 2015); CETESB Companhia de Tecnologia de Saneamento Ambiental, São Paulo, See (accessed ). 4. Balanço Energético Nacional 2016: Ano base 2015 / Empresa de Pesquisa Energética. Rio de Janeiro (Brazilian Energy Balance 2016 Year 2015 / Rio de Janeiro); Empresa de Pesquisa Energética (EPE), Rio de Janeiro, Brasil, Instituto Brasileiro de Geografia e Estatística (Brazilian Institute of Geography and Statistics, IBGE), See (accessed ). 6. National Department of Traffic Road (DENATRAN), See (accessed on ). 7. Kumar, P.; Andrade, M.F.; Ynoue, R.Y.; Fornaro, A.; Freitas, E.D.; Martins, J.; Martins, L.D.; Albuquerque, T.; Zhang, Y.; Morawska, L. New directions: From biofuels to wood stoves: The modern and ancient air quality challenges in the megacity of São Paulo; Atmos. Environ. 2016, 140, ; doi: / j.atmosenv Oyama, B.S.; Andrade, M.D.F.; Herckes, P.; Dusek, U.; Röckmann, T.; Holzinger, R. Chemical characterization of organic particulate matter from on-road traffic in São Paulo, Brazil; Atmos. Chem. Phys. 2016, 16, ; 9. Acompanhamento da Safra Brasileira de Cana de Açucar; Companhia Nacional de Abastecimento (CONAB), Brazil, 2016; ISSN Perez-Martinez, P.; Andrade, M.F.; Miranda, R.M. Traffic-related air quality trends in São Paulo, Brazil; J. Geophys. Res. Atmos. 2015, 120 (12), ; doi: /2014JD Carvalho, V.S.B.; Freitas, E.D.; Martins, L.D.; Martins, J.A.; Mazzoli, C.R.; Andrade, M.F. Air quality status and trends over the Metropolitan Area of São Paulo, Brazil as a result of emission control policies; Environ. Sci. & Pol. 2015, 47, 68-79; doi: /j.envsci Anderson, L.G. Effects of using renewable fuels on vehicle emissions; Renewable and Sustainable Energy Reviews , ; /j.rser Petroleum, Natural Gas, and Biofuels National Agency (ANP) Brazil, See (accessed ). 14. Salvo, A.; Geiger, F.M. Reduction in local ozone levels in urban São Paulo due to a shift from ethanol to gasoline use; Nat. Geosci. 2014, 7, ; doi: /ngeo Martins, L.D.; Andrade, M.F. Ozone Formation Potentials of Volatile Organic Compounds and Ozone Sensitivity to their Emission in the Megacity of São Paulo, Brazil; Water, Air, and Soil Pollut. 2008, 195 (1), ; doi: /s x.