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Paulo Saldiva

Paulo Saldiva: Towards a healthier city

Pathologist presents new hypotheses regarding the effects of urban pollution and advocates air quality improvements

Entrev_Saldiva_18_2JG4900LÉO RAMOSPathologist Paulo Saldiva began studying the harmful effects of urban pollution on health 30 years ago, significantly advanced his professional career, yet was not content to see the results of his work in scientific articles alone.  Little by little, he took his conclusions into other forums in order to improve the quality of air as well as the quality of life in cities.  Saldiva advocates changes in the forms of urban mobility: people should walk more, use public transportation more often or, like him, bike to work, a habit he picked up as a medical student.

Since 2015, Saldiva has supplemented his line of work by using a new and powerful magnetic resonance device to examine cadavers (see Pesquisa FAPESP Issue nº 229). This has enabled him to see that air pollution accelerates the aging of tissues and organs.  He has also adopted practices, such as the minimally invasive autopsy, that allow for confirming diagnoses, verifying medical treatment administered to the decedent and establishing a bank of samples for potential use by physicians, researchers and students.  Married, with two children, Saldiva likes to play the harmonica and photograph the city at night from the balcony of his apartment on the 13th floor of a building in Bela Vista.

What battles are you fighting these days?
My biggest campaign right now is getting Brazil to adopt air quality standards that are compatible with current scientific knowledge.  We’re still behind.  The World Health Organization (WHO) has defined very stringent parameters, but included intermediate levels as targets as part of a management tool.  São Paulo and most Brazilian cities are less polluted than cities in China and India, but government officials here have still not determined what needs to be done to achieve the lowest levels of pollution that constitute the ideal standard.  Leaders of environmental agencies such as the National Environment Council, Conama, contend that we cannot follow international air quality standards because we don’t have the technology to resolve the problem of pollution control, when actually we should be thinking just the opposite: when goals and reality no longer conform, we need to create a movement for change.  Researchers, physicians and other health professionals have to work together to find solutions to these problems.

What have you done to change this situation?
I took an active part on two aspects of the legislation on this subject.  The first was establishment of new WHO air quality standards in 2005, when I helped write the chapter on ozone.  The second was in 2014.  I was a member of the International Agency for Research in Cancer, Iarc, a panel that determined the prevalence of cancer cases attributed to air pollution.  In these two cases, we concluded that there was very solid evidence of reduced life expectancy due to respiratory and cardiac diseases caused by air pollution, and also that exposure to urban pollution, at levels much lower than previously thought, can cause lung cancer.  In other words, it is a small risk, compared to cigarettes.  What we need to take into account is that only 20% of São Paulo’s population smokes, but all city residents are exposed to pollution.  This means that the risk attributable to pollution is significant. Neither the effects of pollution nor urban mobility have yet attained the appropriate level of importance on the agenda for debate of new public health policies.  There is also a relationship with a youth’s capacity for intellectual development, because the four or five hours they would have to rest and study are lost in time spent commuting.  Numerous studies have shown that the problems related to urban mobility harm an individual’s development as a citizen as well as his social and economic growth.  Therefore we need to have a more active mobility standard.  Technology alone will not resolve these problems, but that is not a question of consensus.  There is no consensus when it comes to discussing land use, determining whether public space will be taken up by cars, buses, rail transportation or bicycle, or what type of energy matrix we should use – biodiesel, ethanol, electricity or oil.  They appear to be legitimate interests, put they are at odds.  What’s missing in matters of the environment is management.

Management in what sense?
Management in the form of leadership for the purpose of deciding what is best for the most people.  One example of leadership is the mayor of Dublin, Ireland who in 1987 prohibited sales of coal for heating water.  After the ban, pollution decreased and there was an immediate drop in the number of deaths due to respiratory and cardiovascular diseases.  When they took everything into account, they discovered that there were health benefits as well as financial gains because people and the government began to spend less on doctor’s visits, medicines and hospitals.  There has always been a discussion about how much it would cost to change an energy matrix, but until that time, no one knew exactly how much it cost to maintain a dirty energy source like coal.  With the closure of high polluting factories in Peking in the run-up to the 2008 Olympics, there was a decrease in pollution, an increase in birth weights, and a reduction in neonatal mortality rates and admissions due to respiratory illnesses.  Based on these circumstances, it’s possible to calculate just how high a toll we are paying in terms of health because of urban pollution.

University of São Paulo School of Medicine (Undergraduate, doctorate)
University of São Paulo School of Medicine
Scientific production
Has authored or co-authored 580 scientific articles; advisor for 29 master’s theses and 58 doctoral dissertations

What is the answer then?
It’s not enough to just write a prescription to solve these problems.  Several studies have shown that accidents along the Francisco Morato and Rebouças avenues corridor in the city of São Paulo produce around 10 cases a month of people with permanent physical incapacity, amputations or paraplegia.  Nearly all the accident victims receive care here at the USP emergency room near those avenues.  An alternative for improving care could be to increase the number of emergency room beds and train more residents in orthopedics and neurosurgery, but that would be like increasing the number of beds for thoracic surgery in order to handle more cigarette smokers.  It doesn’t solve the problem.  We have to begin a dialogue with transit authorities and implement urban mobility alternatives so we can reduce traffic congestion on these and other avenues.  Some studies have shown that living just 300 meters away from a park reduces the risk of death from acute heart attack by 30%.  That’s a bigger reduction than what you get by using statins, the main active ingredient in medicines used to lower cholesterol in the blood.  But any cardiologist will tell you that a park has nothing to do with a heart attack.  Those who design parks would say the same thing, but epidemiologists would counter that they do.  The most comprehensive and effective mechanisms for reducing heart attacks are the environmental benefits offered by parks, the increase in moisture levels and the reduction of pollutants in cities.  Besides that, people use parks for walking and exercising.  That’s what happened in Londrina, with its outdoor gyms–plazas with gym equipment available for use by whoever wants to use it.

What happened in Londrina?
In 2009, the mayor purchased the first outdoor gyms and a private health insurance company paid for the rest.  Business owners realized they could make money on this, since people were healthier in regions that had gyms and would therefore make less use of health insurance services.  It’s hard to make a case in academic circles for the notion of focusing urban policy on quality of life and health.  Medical science is prepared to handle environmental issues related to illnesses that have specific causes, such as those transmitted by insects, because that is how it has always been, since back in the days of Oswaldo Cruz.  Yet we are still not paying proper attention to the changes caused by new lifestyles, such as cancer, obesity and mental illnesses.

What can be done?
Attacking these problems requires setting up not just a multidisciplinary team, but a whole network of organizations and professionals, because engineers, landscapers and others all play a role in this.  Diseases caused by an unsuitable urban environment are also the result of property development mismanagement, which causes residents of downtown areas to move to the periphery.  It’s ridiculous for a person to waste three to four hours a day commuting by train, bus or car.  I’ve adopted an alternative: I’ve been riding my bike to school since I was a medical student, but I’m looked at as engaging in “exotic behavior.”  Health professionals have to take a leadership role and put forth positions that favor improving quality of life in cities.  They also need to pay more attention to grocery store shelves, which represent another public health problem.  Foods, especially sweets, that a 2- or 3-year-old child sees on shelves and in boxes lead to obesity and set inappropriate eating habits right from the start.  We have been able to clearly and convincingly present the risks of cigarette smoking and get a lot of people to stop smoking, but we still have not been able to mobilize people to take precautions against the risk of consuming foods that promote obesity, nor about the consequences of improper standards, from the public health standpoint, of urbanization and land use.

Why is obesity associated with urban mobility?
It doesn’t make sense to discuss this subject by talking only about hormones or diet, without discussing cities.  In an article published in the journal Nature Reviews Cancer in September 2013, entitled “Air pollution: a potentially modifiable risk factor for lung cancer,” we showed that the obesity rates in several countries was lower when the population adopted active modes of transportation, such as walking, cycling or even riding the subway or buses.  People using public transportation in São Paulo walk one to three kilometers a day when commuting.  Without going into how the type of mobility is related to obesity rates, I won’t be able to study the entire history because a substantial part of obesity is caused by an individual’s lack of activity.  We have to encourage public transportation as a way to promote health.

How do you address these possibilities for involvement?
Basically, by writing white papers–scientific articles that can influence the development and implementation of public policies.  The article in Nature Reviews Cancer shows what we can do from the standpoint of sustainability on the part of people and countries.  There is no point in leaving the car home, taking bucket baths or living in the dark.  We have to show that it’s possible to expend 350 calories a day by walking four kilometers, using public transportation.  In another article that came out in July 2015 in the Lancet entitled “Mortality risk attributable to high and low ambient temperature: a multi-country observational study,” we took part in a consortium that examined temperature variation and mortality in 384 cities.  This effort showed that we live better at a temperature slightly below ideal, because the physiological mechanisms of adaptation are more efficient in fighting cold than heat.  In São Paulo, where the average temperature is 22º Celsius, mortality increases when the temperature goes above 26ºC or below 18ºC.  If it exceeds 30ºC, there is a 50% increase in mortality mainly due to heart attacks.

What exactly is this caused by?
One of the main culprits are urban heat islands [a city’s hottest areas].  To increase mortality in Stockholm, the temperature has to fall below zero, while in Teresina, capital of the Brazilian state of Piauí, it’s remarkable, it just has to fall below 23ºC.  Some cities, like Toronto, are becoming resilient and building a temperature conditioning system that makes it easier for people to adapt to the cold.  Older cities such as Madrid and London are better able to handle the cold than the heat.  When it gets hot in London, mortality is 2.5 times as high.  Adequate temperature control in the heat islands and reconstitution of vegetation coverage are important for reducing mortality among city dwellers.

Tell us a little about your work with non-governmental organizations (NGOs).
With NGO teams like the Health and Sustainability Institute we’ve prepared reports using absolutely transparent language regarding mortality and the health costs of pollution in the city of São Paulo.  To bring about changes in behavior, we have to produce the best science possible and then empower that knowledge through user-friendly writing aimed at the general public and officials.  In this regard, NGOs are efficient.  Academic structures can also be efficient in translating scientific knowledge to the general public and orchestrating policy.  Harvard University does this very well.

The School of Public Health at Harvard has produced publications written by journalists who take part in the discussions and set the agendas for major newspapers and magazines in the United States.  In 2015, the New York Times reported on a Harvard study that showed that the worse the mobility, the less time people had to study and the lower their future earnings.  This made an enormous contribution for whoever studies and for those engaged in urban policy. The study is currently being discussed in the U.S. Congress.  Taking this scientific knowledge to other audiences in a professional, neutral and efficient way is still a huge challenge for academic institutions in Brazil.  Here in Brazil, most researchers still believe that their work is done when it is published in Nature or Science.  The academic system rewards only research and academic production.  There are no mechanisms in place to reward involvement in public policy or collaborative activities.

Why did you start studying the effects of pollution back in the 1980s? 
I was completing my pathology residency when I met György Böhm, an extraordinary Hungarian professor who had moved to Brazil and was studying air pollution in cities, and I became enamored with this topic.  At that time, in the 1980s, air pollution was a cause looking for a disease.  It was believed that the standards established in the United States during the 1970s, once achieved, would have no negative impacts. In experiments with animals and later in epidemiological studies, we were able to demonstrate a strong association between pollution, mortality, sickness, inflammation and the formation of malignant lung tumors in mice.  The effect was not devastating, but it was very clear.  We also showed, in animal models, the effects of exposure to pollution during pregnancy.  Compared with the control group, animals subjected to intense pollution during pregnancy had lower birth weights, fewer pulmonary alveoli and changes in some areas of the cerebral cortex.  Pollution also changes the sex ratio, resulting in the birth of more females than males.  Because of pollution, there is a hormonal imbalance and possibly a harmful effect on the male sex chromosomes, with survival more likely of the X over the Y.  History has confirmed this data.  In 1978, there was an accident in Cevezo, Italy involving a polyvinyl chloride spill and for a period afterwards, only girls were born.

How was your trip to Harvard in 1999?
I’d become a full professor in 1996 and was heading up the Main Laboratory of the Hospital das Clínicas.  I did only this for three years.  I was incredibly unhappy, not knowing if I would know how to teach classes, or whether I was a researcher or an administrator.  I thought: “I’m going to take a break and go on sabbatical.”  My children were 11 and 12 and I thought that before long, they’d be too grown up and things would get harder.  I went there as a visiting professor, without a project.  I got to the Harvard Medical School and they asked me: “What’s the direction of your research?”  I answered: “I have none.  Tell me what you need done and I’ll help wherever I’m needed.”  They had a lot of important experiments that had stalled.  I prepared microscope slides with organ and tissue samples, I began conducting analysis and did my most cited work to date, demonstrating that the accumulation of particles from air pollutants caused reductions in pulmonary vascular resistance.  It was the first solid evidence that air pollution causes vascular alterations in animals, affecting not just the lung parenchyma (the outermost layer of the lungs), but also the pulmonary artery.  In another study,  I demonstrated the relationship between pollution and acute arrhythmia.  Five publications came out that year and I set up a system of experiments that focused on airborne particles and allowed me to do a series of important studies later, in Brazil.

What can possibly be brought from Harvard to be used here in Brazil?
The first thing would be merit pay.  At Harvard, anyone who does not bring in money – because a share of the funding goes to the university – or does not become an expert in his field, has to leave, just like that.  Harvard has adopted a completely impersonal model based on competitiveness.  Something else that could help us think about our situation is not wasting time on bureaucracy.  If a researcher wants a reagent, he calls whoever is in charge of reagents and it’s on his desk the next day.  Here it is still a little different.  I spent a good part of 2014 managing a project to install Tesla 7 nuclear magnetic resonance equipment for use in autopsies and other studies funded by FAPESP.  We had to follow a Germanic import timeline while we carried out the work according to a Brazilian timeline, but, amazing as it may seem, it turned out alright.  At Harvard, there is a group that would have done this for me because it was thought that researchers shouldn’t waste time on such things.  There is a lot more efficiency and the work environment is much more competitive.  No one stays in his or her comfort zone.  And there is a lot of freedom there.  Professors can wear shorts or work the hours that suit them – there is no monitoring of schedules.  In this way they enjoy a creative environment.  Here no.  We have procedural indicators, we evaluate the number of class hours or students but no one asks: what came out of that, what did you change?

How is work going with the new autopsy device?
It is going very well.  The project began four years ago with Edson Amaro, now an associate professor in the Department of Radiology, when we asked each other: what is our competitive edge?  What can we do better than Harvard or Oxford?  We have the world’s largest autopsy room. We do 14,000-15,000 exams of this type each year on people who died of natural causes because in addition to the cases at Hospital das Clínicas, we have the Division of Postmortem Inspection, associated with the São Paulo State Secretary of Health.  So we’re going to wager everything on this field for teaching, research and training.  Everyone was amazed.  It was one of the few times that an idea started and ended [successfully] within the School of Medicine.

What do they plan to do with the new equipment?
Now we’re able to study rare diseases as well as see the difference between chronological age and biological age, already assessed through genetic and biochemical exams but not yet by evaluating the structural changes in the body.  One of the hypotheses we’re testing is that air pollution, independent of other factors, causes our organs to age more quickly.  We’re seeing that pollution can reduce the functional reserve of our organs just as if we had smoked, which produces premature senescence.  Together with the Ministry of Health and the group from Global Burden of Disease, we are also comparing the verbal autopsy, an indication of likely cause of death, with the actual one.  Christopher Murray, professor at the University of Washington and founder of the Global Burden of Disease (GBD) approach, visited São Paulo in 2015 and found out that we are also performing minimally invasive autopsies.  Our approach consists of an imaging exam and a macroscopic anatomical analysis.  Where we find any sign of disease, we use a needle to remove a small sample from a tissue or organ, such as the brain – which would be impossible with a living person – after obtaining authorization from the family.  We are also comparing exams conducted using this technique with those conducted using conventional autopsy.  In less than a year, we’ve conducted 400 minimally invasive autopsies and we would like to complete 1,000 by the middle of 2016, comparing them with conventional autopsies and seeing when one or the other could be used.  There is a huge difference in cost.  A conventional autopsy costs nearly R$8,000, considering labor and analysis and the minimally invasive one costs R$1,500.  It’s also a simpler way to confirm diagnoses and determine whether we actually did everything that could have been done for the patient.

Are they already doing this?
Look at this [showing an image on the computer screen], a fracture of the occipital bone.  We are able to see the injury without opening up the individual.  In order to see this in a normal autopsy, we would have to mutilate the cadaver.   And we can do a 3-D print of it and use the images as legal evidence, without needing to exhume the body.  Here [he shows another image], is the heart of someone with atherosclerosis.  We can do a postmortem angiography by perfusion using a synthetic derivative of plasma and iodine, set up a bank of normal tissue and study emerging viruses, among other things.  We can make a difference in public health if we can prove that it is possible to perform postmortem collections guided by imaging.  Besides this, we have talked extensively with the families after removing tissue for analysis.

How do the conversations with families go?
First we explain the death certificate, which few people understand.  Then we try to prevent similar deaths from taking place in the same family.  One recent case involved a man with a descending thoracic aortic aneurism who was found dead.  When speaking to his siblings, I asked if they had high blood pressure.  All of them did, and one had even experienced chest pains 15 days prior.  I told them that they needed to control their hypertension and that it had been one of the reasons for the death of their brother and that when they have chest pain, they need to tell their doctor that there have been two cases of deaths due to aneurisms in their family: one proven through autopsy and the other supposedly through clinical tests.  This contact has given me a lot of personal gratification and I can guarantee that it has given the family a certain sense of relief.  We are harnessing our efforts to promote health and prevent similar cases from occurring, thus preventing other deaths.