Environmental and public health cost-benefit evaluation of the bus transportation system in Sao Paulo, Brazil

São Paulo city, Brazil, with 11 million inhabitants, requires a transportation system to attend to the demand of the population. This system is composed by bus (14.761), an insufficient subway network coverage and individual transportation. Estimates of the vehicle fleet is 6.5 million.
Traffic is the main source of air pollution in São Paulo, being responsible for 90% of inhaled particulate matter emissions - PM₁₀. The pollutants are associated to the incidence of respiratory, cardiovascular diseases and neoplasia, impacting the health system in terms of hospital admissions, emergency room visits and increasing mortality.
The study evaluated the environmental and health benefits of the bus fleet renewal in the municipality of Sao Paulo in terms of air pollutants’ concentration and associated mortality indicators in the period of 1996 to 2006 compared to the costs of the buses incurred in the renew process initiated in 2002.
We performed a temporal evolution analysis of pollutant concentrations associated to elderly mortality indicators and buses fleet from 1996 (baseline year) to 2006 and the health costs compared to buses investments.
The results showed the positive effects of this measure converted by the diminish of the annual average concentrations of PM₁₀ from 60.69 mg/m³ in 1996 to 32.62 mg/m³ in 2006. This 50% reduction in the pollutant concentration is associated to a drop of 7% in the mortality panorama after a lag of 2 years of the environmental improvement and the investment of US$ 1 billion in cleaner technologies buses.
Considering this investment was performed through 5 years, we could estimate an average investment of US$ 200 million per year. This value is equivalent to the annual health costs estimated by Miraglia et al. (2005). The cost-benefit analysis of Sao Paulo’s public buses fleet renew can be considered positive.