MIGUEL BOYAYANIn one of the rooms of the children’s first aid clinic at the São Paulo Hospital and Clinics, João Vitor, 1 year, 5 months old, has just been doing inhalation. He had a cold and was still coughing a lot, but his respiration had now calmed down. “We live in a house with little ventilation, just one window, and the air gets stale”, said his mother, Maria da Conceição da Silva Araújo. Calmer, she left with her son, and the room became empty. It is a very different scenario from the agitated months of May, when the clinic recorded an average of 211 consultations a day, or June, with almost 200 a day. The search for inhalations was intense, since 70% of the complaints were related to respiratory difficulties, caused in great measure by the dry winter weather, when the levels of pollution also increase. In spite of the advances achieved in the last decade in controlling the emission of gases and polluting particles, to breathe the air of São Paulo continues to be an act of heroism, and not merely for the children. It is estimated that nine people a day still die in the city, as victims of cardiovascular or respiratory problems or lung cancers, directly or indirectly associated with atmospheric pollution.
Every year, pollution is responsible for the death of about 3,500 inhabitants of the city of São Paulo. If we consider only the economic impacts, the loss of these lives means a total cost of US$ 350 million, taking into account the potentially productive years of life that have been lost or the prospect of living with chronic diseases that reduce the capacity for work, according to a study coordinated by Paulo Saldiva, a professor from the School of Medicine of the University of São Paulo (USP). Nelson Gouveia, who also lectures at USP’s School of Medicine, published in March in the Environmental Research magazine a paper showing that São Paulo, Mexico City and Santiago, in Chile, could prevent 150 thousand deaths, 4 million asthma crises, 300 thousand internments of children, and 48 thousand cases of chronic bronchitis in a period of 20 years and generate savings of US$ 165 billion, if they were to reduce the levels of pollution to the parameters indicated by the World Health Organization (WHO). Other recent surveys reveal that polluted air can be very harmful to two groups of the population. The first is pregnant women, making babies be born with less weight and even interfering in the sex of the babies: in more polluted regions, more girls are born than boys. The other group is the traffic inspectors, whose organism suffers such intense alterations from the air on the street that substances associated with heart attacks are released into the blood.
Vehicles are still the main culprits for the layers of thick gray smoke that form in the São Paulo sky. They can be clearly observed on the horizon, particularly in the winter. That is when heat inversion – the formation of a lid of hot air close to the surface that prevents colder air from rising – makes it difficult for the gases and toxic particles to disperse. The particles are not diluted and become larger and with less humidity. The respiratory airways of the human body produce less mucus to filter the impurities of the air, which thus enter into the organism more easily, attack the defense cells of the organism, and reduce the capacity for resistance. The throat grates, the eyes itch. “Without care, the picture may be aggravated and the way opened for ear inflammations, asthma crises and pneumonias”, observes Roberto Tozze, an assistant doctor at the Children’s Institute of the São Paulo Hospital and Clinics.
Advances
The pollutants originate essentially from the exhausts of the 7.6 million vehicles that circulate in the largest Brazilian city. The Program for Controlling Air Pollution by Automotive Vehicles (Proconve), managed by the Environmental Sanitation Technology Company (Cetesb) of São Paulo and implanted as from 1996, minimized the problem by requiring the cars to leave the factories already with catalytic converters and electronic injection, which control the emission of pollutants. The maximum limit for carbon monoxide concentration was exceeded 65 times in 1997, but only once in 2005. According to Saldiva’s study, which evaluated the decade from 1996 to 2005, Proconve also reduced the economic impacts of pollution, preventing 1,500 deaths a year, which means annual savings, in terms of productivity, of US$ 150 million. “We have improved, but we are still paying an extremely high bill”, comments Saldiva.
MIGUEL BOYAYANProconve seems to have reached a limit. The dilemma is difficult to resolve: the periodic inspection of the vehicles, although provided for in the legislation, does not happen in practice. If the catalytic converter stops working, there is no way of guaranteeing that it will be repaired. “There was no definition of how the maintenance would be handled, in what way and when the motorists would be summoned, and who would bear the costs”, says Jesuíno Romano, the manager of Cetesb’s technology division for evaluating the quality of the air. The average of the São Paulo fleet is another obstacle. According to São Paulo’s State Traffic Department (Detran), half the cars that were circulating in June 2006 were over ten years old.
If the carbon dioxide levels reach acceptable figures, the emissions of ozone and particulate matter, like zinc, manganese, nickel and lead, still exceed the limits established by the Brazilian legislation. “Any vehicle, even with the most modern technology, emits ozone precursor elements, even though in reduced quantities”, comments Simone Georges El Khouri Miraglia, a professor at the Senac University Center and a research at USP’s Atmospheric Pollution Laboratory.
Controlling the particles is also not a simple matter. They are emitted basically by the exhausts of the trucks, driven by diesel, that make up an even older fleet: almost 70% of São Paulo’s trucks left the factory over ten years ago. Furthermore, the city of São Paulo is a point of passage for trucks that come from other regions of the country.
Who suffer a lot from this pollution are the traffic inspectors. “The gases suffocate you and leave your face black”, says Waldir Bravo, who for years worked at the intersection of Estado and Mercúrio avenues, in the center of São Paulo, before becoming a representative of the employees on the Management Council of the Traffic Engineering Company (CET).
Risk of a heart attack
“I would be standing up for six hours, facing the ring road, above the Bandeiras bridge, with trucks and cars passing by on both sides, sucking in all that concentrated smoke, with no place to escape to”, describes Venceslau Coimbra, a traffic technician who took part in a study coordinated by Ubiratan de Paula Guimarães, a doctor from the Heart Institute (InCor). In a paper published in the European Heart Journal, Guimarães evaluated 50 workers from the CET – the so-called “brownies”, because of the color of the uniform they use – who worked on the Tietê and Pinheiros ring roads.
In the winter months, which record the highest concentrations of pollutants, the workers showed high blood pressure, a decrease in the variation of the heart rate (the heart becomes more rigid, which can cause sudden death) and inflammation of the bronchi, which ending up releasing a high quantity of substances associated with a heart attack, such as C-reactive protein. “I suggested to the company a long-term accompaniment, to think up preventive measures”, Guimarães says. “The intention is to take advantage of the work to modify the legislation and to classify our work as arduous”, claims Luiz Antonio Queiroz, the president of Sindviários, the entity that represents CET’s workers.
The effects of atmospheric pollution on pregnancy are also dangerous. Gouveia saw that exposure to high levels of pollution (10 micrograms a day of carbon monoxide in excess of the acceptable standards, for example) during the first quarter of pregnancy can contribute towards the babies being born with less weight – on average, 20 grams less. The study, published in the Journal Epidemiology Community Health, compared the figures from the Live Births Information System (Sinasc) with the records of pollution noted down the Cetesb’s measuring stations in the different months of the year. “Carbon monoxide causes low oxygenation of the blood, and particulate matter impairs the vascularization of the placenta”, Gouveia explains.
Pollution in excess also appears to interfere with the definition of the sexes in babies. In regions of São Paulo more affected by pollutants, there are 2% more newborn girls than boys: in areas with less intense pollution, the score is reversed, and 3% more boys are born. “We reproduced the situation in the laboratory, with mice, and the results were similar”, adds Saldiva, the author of the paper, which will be published in Fertility and Sterility. The gases and the toxic particles must affect the testicles. The Y chromosome, which defines the male sex, may be more susceptible to lesions, making possible a relative hegemony of the X chromosome, responsible for the female sex.
The specialists agree: atmospheric pollution could be one source of less concern for the citizens of São Paulo, should some elementary measures be implemented. And the implantation of public transport in quantity and with quality, the creation of more bus lanes, and the expansion of the subway lines, the modernization of the fleet of diesel-fueled trucks, and the effective application of the vehicle inspection program, added to environmental education. We have failed in the dialog with the city hall, observes Saldiva. “We have produced many good studies, but it’s time to transform these papers into public policies.”
The Project
The impact of intrauterine exposure and exposure in the initial stages of postnatal development to atmospheric pollutants on the development of adverse alterations in adult life (nº 03/10772-9); Modality Thematic Project; Coordinator Paulo Saldiva – USP; Investment R$ 361,802.28 and US$ 188,272.68 (FAPESP)
