With congested roadways, higher temperatures, and social barriers, large cities can be easily perceived as sick bodies. Similarly, the cells in this body (city dwellers) tend to be equally unhealthy. Mobility, or lack thereof, is one characteristic of cities that brings together the most obvious problems. Motor vehicles lead to sedentary lifestyles and are responsible for most polluting emissions that cause a series of ill effects. Traffic headaches resulting from too many cars increases exposure to pollution and reduces time that could be spent on social life and enjoying the city itself. It is a troublesome situation, but the good news is that this may present potential solutions, not necessarily a death sentence. “In São Paulo there is huge room for improvement in transport, dwellings, and urban design,” says public health specialist Thiago Hérick de Sá. Sá is a researcher associated with the Center for Epidemiological Research on Nutrition and Health at the University of São Paulo (NUPENS-USP), coordinated by the physician Carlos Augusto Monteiro; today, he works at the World Health Organization (WHO) in Geneva, where he is trying to put theory into practice.
Concerns about the health of cities are not trivial. Urban areas make up less than 1% of Brazil’s territory, but are home to 84% of its population, one of the highest rates in the world. But the city of São Paulo has a unique characteristic: only 10% of its 12 million residents live in what is known as the expanded center, which provides better infrastructure for getting around on foot, by bicycle, or via public transport. The other 90% need to travel long distances and rely on inefficient transportation, in most cases, or face daunting traffic.
Consequently, both the city’s Master Plan, which was approved in 2014, and the strategic plan “São Paulo 2040: The city we want” outline strategies to make transport more inclusive, less individual, and less motorized. Based on these ideas, Sá considers a scenario in which most trips do not exceed half an hour and largely involve walking or bicycles, with 70% of motorized trips using public transport. This situation, compared with the current alternatives in São Paulo or cities abroad, could avoid 1,224 deaths attributed to physical inactivity each year (cardiovascular diseases, some cancers, diabetes, dementia, and depression) and another 406 which are the direct result of atmospheric pollution, especially cardiovascular problems, according to findings published in November in the journal Environment International. Known as a comparative risk assessment, this type of scenario calculates years of life lost in different situations, including the years lived in disability resulting from accidents. The results suggest that the investments required to improve transport conditions would be lower than the costs of death and disability. “Health concerns do not tend to be part of public policies, and this leads to more deaths and higher costs,” says Sá.
According to data published in The Lancet in 2016, one in every three adults and four of every five teenagers in the world do not perform the levels of physical activity recommended for health and preventing disease: 150 minutes per week of moderate or vigorous activity, or at least 75 minutes per week of vigorous activity. Using data from the 2015 São Paulo Municipal Health Survey, epidemiologist Alex Florindo of the USP School of Arts, Sciences, and Humanities (EACH-USP) evaluated the impact parks, squares, and bike paths have on the physical exercise habits of São Paulo residents, specifically walking. The results, published in June in the International Journal of Environmental Research and Public Health, indicate that having at least two of these types of public spaces within a 500-meter (m) radius of one’s home increases the chances that people will practice physical activity in their leisure time, especially in squares and on bike paths. However, only one-third of the city’s inhabitants enjoy this availability; one-fifth of São Paulo dwellers do not have any of these structures near their homes.
The presence of a bike path increases the chance that people will walk during their leisure time by 55%. An extension of the study, presented in August at the International Congress of Epidemiology in Japan, added that people living within 500 m of a bike path are more likely to use bicycles as a means of transport, and that the presence of subway or train stations within 1 kilometer (km) of home is associated with walking. “This is true for any region of the city. More structures need to be distributed more equitably,” says Florindo. “Without help from the environment, this sedentary situation cannot be improved.”
Part of this involves reducing often-lethal heat by planting trees. “In Brazilian cities, the rule is invasion by asphalt and concrete, to the detriment of nature,” warns geographer Magda Lombardo of São Paulo State University (UNESP) in Rio Claro. In her 1985 dissertation, she showed that the hottest areas of São Paulo reached temperatures 10 degrees Celsius (°C) hotter than cooler areas. Since then, this contrast has increased to 15°C. Lombardo says that the temperature is 4°C higher in busy avenues, and a shopping center can cause an increase of 2°C in the area it occupies.
Florindo emphasizes that it is up to public authorities to provide the constructed environment that opens up possibilities for the population. The 2014 Master Plan seeks specifically to reduce environmental inequalities and considers bike paths to be essential in this process. One student in his group evaluated the busiest bike lane in the city—on Faria Lima Avenue in the west zone—and noted that the use of this lane has grown over the course of a year. Another member of his team is examining the cost-benefit ratio for the Minhocão elevated park (officially, João Goulart Avenue) in the central zone for leisure activities. This long and inhospitable elevated roadway is closed to cars at night and on weekends, creating a space for a variety of artistic, sports, and social activities. A law transforming it into a permanent park has already been approved. During the Brazilian Congress on Physical Activity and Health, which was held in November in Florianópolis, Santa Catarina, it became clear that the current challenge is urban interventions.
Florindo has assembled a multidisciplinary team to study what encourages or impedes physical activity in the city, with experts in economics, geography, epidemiology, and architecture, as well as public participation. But influencing decisions is more difficult: most of the researchers find it difficult to dialog with managers and decision-makers in order to put the study’s findings into practice.
A natural experiment came from the Academia da Cidade [City Gym] program introduced in 2006 in Recife, Pernambuco, to offer free opportunities for physical activity guided by professionals. Initial success led to the expansion of this initiative to 184 cities in the state in 2008. A group led by the epidemiologist Eduardo Simões, who hails from Pernambuco but is a professor at the University of Missouri, assessed the results of the program in 80 cities in 2011, 2012, and 2013. The results, published in October in the journal Preventive Medicine, revealed a significant effect in women and showed the importance of long-term initiatives: in cities where the program had been running for less than three years, women who participated were 9% more likely to achieve the level of physical activity recommended by the WHO. When the program was established for an even longer period, the benefit rose to 46%.
In 2011, the program was expanded to other parts of Brazil and renamed Academia da Saúde [Health Gym]. “It moved from a program promoting physical activity to promoting health in general, and lost its focus,” says Rodrigo Reis, a specialist in public health and urban planning and professor at Washington University in Saint Louis, in the United States. He coauthored the study in Preventive Medicine, and regrets the fact that the program was changed before its cycle was complete and its impact could be fully assessed. “The decision to change was not based on evidence.”
Up to 2016, while he was a professor in the graduate program in urban planning at the Pontifical Catholic University of Paraná (PUC-PR), Reis participated in evaluations of the practice of physical activity in Curitiba and other cities, like Vitória, Espírito Santo, in different age groups. Factors such as good sidewalks, public lighting, transport, and security promote physical activity. Now his challenge is to apply what he learned in Brazil to his work in Saint Louis, in terms of research that supports real changes. “The racial, political, and social context is more complex, with more inequality,” he adds. “The city had planning that resulted in the segregation of the Black population, which is also poorer.”
He is studying the planned expansion of the light rail network in Saint Louis. “We used several methods to analyze how public transport affects quality of life and facilitates access to work, hospitals, leisure facilities.” This calculation also includes the needs of each community, walking times, rates of bicycle use as transport, and the ideal distance between stations.
Reis explains that the link between public health and urban planning is expanding around the world. “Twenty years ago it was uncommon to think about it, but today it is no longer fashion, it’s a necessity,” he says. The view of a public health specialist differs from a traffic engineer, for example, who needs to worry about how people can safely go from one point to another. “What’s best for the city? And for the health of the population?” he asks. Reis argues that the city must offer alternatives so that each person can choose their own modes of leisure, transport, and physical activity. “Each citizen needs to realize that they transform and shape the city when they use a bus or drive.”
The context in large cities like São Paulo requires long daily commutes that lead to a sedentary lifestyle and the mandatory loss of hours of sleep. “When the city becomes an obstacle, it prevents people from meeting,” says physician Paulo Saldiva of the USP School of Medicine. The result is worrying obesity across all age ranges, including children. In his opinion, a cultural shift is necessary. “The percentage of smokers in São Paulo dropped from 40% in the 1960s to 12% today, but not because people stopped smoking,” he says. “The new generation devalued cigarettes in terms of symbolism. The same is happening with cars: today, ownership is less important than usage.”
A study by Saldiva’s group which has not yet been published used lung autopsies from São Paulo residents to calculate that every two hours in a car in traffic corresponds to one cigarette smoked. “Immobility imprisons the person in the worst place to be,” he warns.
Atmospheric pollution causes 16% of deaths around the world (or 9 million premature deaths), according to the Global Burden of Disease Study based out of the University of Washington in Seattle. This number is 15 times greater than victims of war and violence in other contexts. The Breathe Life campaign from the WHO and the United Nations (UN) Environment Programme explains that airborne pollution accounts for roughly one-third of deaths from lung cancer, strokes, cardiovascular disease, and chronic obstructive pulmonary disease (COPD). Cities that have joined the campaign (so far, 37, but none in Brazil) are committed to reducing air pollution to attain the WHO goal of 10 micrograms of 2.5 particulate matter (PM 2.5) per cubic meter of air (µg/m3). This component of emissions is considered to be the most dangerous to health, since it enters the respiratory system and has a large potential to cause problems. São Paulo, with an annual rate of 19 µg/m3 exposure to PM 2.5, exceeds the international target by 90%. According to data released by the campaign, more than 26,000 people die each year throughout Brazil as a result of pollution, mostly from ischemic cardiopathy.
Active transportation (walking or cycling) is the best way to reduce the damage caused by polluted air, even if this physical exercise makes people breathe more, according to a study led by epidemiologist Marko Tainio from the University of Cambridge, UK, and published in 2016 in Preventive Medicine. The study, which also included Thiago Hérick de Sá, found that even in very polluted areas with PM 2.5 concentrations of 100 µg/m3, it would be necessary to cycle more than 1.5 hour per day or walk 10 hours for this particulate exposure to outweigh the benefits of exercise, assuming that the alternative was staying at home. In comparison with driving, active transportation is even more advantageous.
On an individual scale, the numbers are not impressive. Physical therapist Laís Fajersztajn from the USP Global Cities Program at the Institute of Advanced Studies (IEA) surveyed Latin American studies and found an increase of only 2% in the risk of death due to respiratory problems and 1% in deaths from cardiovascular disease associated with high levels of PM 2.5, as shown in a September article in the International Journal of Public Health. “Smoking has a much greater impact,” she explains. “But this only applies to smokers, whereas the entire population is subject to air pollution.” In her opinion, the most important aspect of her results was the realization that they are in line with findings from other countries, including those with higher incomes. “There is no need to repeat what has already been done, what is lacking is to improve the data, measure the concentration of PM 2.5 in a broader way to see patterns.” In an attempt to increase this awareness and call for further studies on pollution and its effects, in October of this year the medical journal The Lancet launched a commission on pollution and health, and plans to inform policymakers about the economic and social costs associated with this problem.
Monetary costs are the focus of engineer Simone Miraglia from the Diadema campus of the Federal University of São Paulo (UNIFESP). Using the health impact assessment technique (HIA), medical biologist Karina Abe estimated during her doctoral research at UNIFESP (which was advised by both Miraglia and Saldiva) that São Paulo would prevent 5,000 deaths and save US$15 billion per year if the city reached the WHO PM 2.5 reduction goal, according to her article published in 2016 in the International Journal of Environmental Research and Public Health. “What you can do with more time of life?” the engineer asks. Since motor vehicles are the main source of pollutants, she has been looking for ways to contrast the economic value of taking action versus keeping the status quo. In this context, biologist Luciana Leirião, a master’s student in Miraglia’s research group, projected a scenario in which the older cars in São Paulo would be replaced by newer ones. The data, which have not yet been published, showed a significant drop in environmental pollution. “There should be an incentive program to renew the fleet, with tax cuts and vehicle inspection,” says Miraglia.
Solving these problems requires considering cities for people. Some regions of São Paulo are cut off by overpasses, train lines, and rivers that isolate instead of connect, and make walking impossible. “Many cities around the world are developing strategic plans, which should work in harmony with the master plan,” says engineer Miguel Bucalem of USP’s Polytechnic School during a seminar in the IEA’s Global Cities program. He spearheaded the drafting of the São Paulo 2040 plan within São Paulo city government from 2007 to 2012, and emphasizes that the social, economic, environmental, and urban spheres must be involved. “The idea is to have city extend throughout São Paulo: compact, polycentric, and equivalent.”
A well-known case in Brazil is Fortaleza, Ceará, which since 2013 has been governed by mayor Roberto Cláudio Bezerra. “The debate around health rarely considers well-being in the city as the real right to health,” he says. He consequently decided to favor the city as a space promoting health through initiatives focused on urbanism and mobility, encouraging collective or active transport in order to reduce pollution and boost road safety. In November, his administration celebrated a reduction in traffic deaths, which in 2016 dropped below 300 for the first time since 2002 after the implementation of a series of measures resulting from a partnership with the Bloomberg Road Safety Initiative of New York. “A 2003 study by IPEA [Institute for Applied Economic Research] estimated the cost of traffic accidents in Brazil, which in Fortaleza was R$720 million per year,” says Luiz Alberto Savoy, executive secretary of Fortaleza’s Department of Conservation and Public Services. He reports that a third of hospital beds in the city are occupied by victims of traffic accidents, 90% of them among the most vulnerable: pedestrians, cyclists, and motorcyclists. “We were taught to see this as inevitable, but it is an avoidable cost, an epidemiological question.”
In his second term as mayor, Bezerra states that there are no more difficulties implementing bus corridors or bike paths. “We had a change of culture.” Today the city has over 250 km of bicycle lanes, up from 68 km in 2013, and around 100 km of exclusive bus lanes, which more than doubled average speed. Another initiative is bicycles available for free inside bus terminals. The idea is to help those who live in remote areas complete the last stage of their trip, allowing them to keep the bike at home for up to 14 hours.
“We established a road safety observatory in partnership with local and American universities,” adds the mayor. One example of these partnerships was a study headed by Sudha Ram, a specialist in information management systems at the University of Arizona (where Bezerra received his doctorate), which used data generated by the single-ticket system to analyze passenger routes and suggest adjustments to the bus network. “This partnership helped us to realize new aspects of public policies, such as monitoring operating speeds in the corridors and boosting the deployment of shared bicycles and their integration for bus passengers,” says Savoy. It’s a good example of research and practice that inform each other.
1. The use of household travel surveys in the study of active transportation (n° 13/25624-7); Modality Auxílio à Pesquisa – Regular; Principal Investigator Carlos Augusto Monteiro (USP); Investiment R$ 164.020,34
2. Development of population indicators of the built environments to promote physical activity in São Paulo City (n° 14/12682-1); Modality Bolsa no Exterior – Pesquisa; Grantee Alex Antonio Florindo (USP); Host Billie Giles Corti (Universidade de Melbourne, Austrália) Investiment R$ 140.372,02
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