Road transportation has contributed to increased emissions of conventional air pollutants and, consequently, to the increase in problems associated with the environment and human health, depending on the type of pollutant and the concentration of it. To support the development of public policies aimed to decrease total tonnes of emissions, we used a bottom-up approach to estimate the amount of air pollutants, such as carbon monoxide (CO), total hydrocarbons (THC), nitrogen oxides (NOx), particulate matter (PM), and aldehydes (RCHO), that are emitted by road transportation in the state of Rio de Janeiro (RJ) from 1980 to 2010. The results from 2010 show that cars are responsible for 55% of CO emissions, 61% of THC emissions, and 93% of RCHO emissions. Due to the use of hydrated ethanol and compressed natural gas (CNG) instead of petroleum based fuels during the period analyzed, 1,760,370 t of air pollutant emissions were avoided. Compared to Brazil, in 2010, RJ had a quantity of emissions per vehicle from 12% (CO) to 59% (PM) smaller than the national average. As strategies to reduce air pollutant emissions, we consider reducing the intensity of use, with a proportional reduction in emissions, and increased the use of biodiesel.
Due to an energy dependency on petroleum products such as gasoline and diesel fuel, road transportation has contributed decisively to the emission of atmospheric pollutants, with consequent problems for the environment and human health (Faiz, 1993, Colvile et al., 2001, Saija and Romano, 2002, Öner and Altun, 2009, Uherek et al., 2010 and Progiou and Ziomas, 2011).
According to the Brazilian Ministry of Mines and Energy (MME), Ministério de Minas e Energia [Ministry of Mines and Energy], 2011, in 2010, the transportation sector consumed 53.1% of petroleum derivatives, of which 90% was used in road transportation. By analyzing the Brazilian states, we see that the state of Rio de Janeiro follows the national trend and stands out with the second highest Gross Domestic Product (GDP) in the country (11.3%) (IPEA, 2011). During the next five years (2012 to 2016), it will host international events such as the World Cup in 2014, and the Olympic Games in 2016.
Because of Rio de Janeiro’s contribution to the Brazilian economy and its global exposure, it is important to identify the state’s contribution to atmospheric pollutant emissions from road transportation in order to highlight upcoming opportunities to show the rest of the world how a country can successfully make the transition to cleaner transportation.
In the last two decades, the automobile industry has invested in technologies to reduce the emissions of air pollutants from road motor vehicles, prompted by stricter legislations. To support the development of public policies aimed to decrease total tonnes of emissions, it is essential to preparing an inventory of air pollutants emitted by the transportation sector in the state of Rio de Janeiro, specifically road transportation by its importance.
In this context, this study aimed to (1) estimate the quantity of conventional air pollutants such as carbon monoxide (CO), total hydrocarbons (THC), nitrogen oxides (NOx), particulate matter (PM), and aldehydes (RCHO) emitted by road transportation in the state of Rio de Janeiro from 1980 to 2010; (2) compare the fleet size of road motor vehicles, fuel consumption, and emission of these pollutants in the state of Rio de Janeiro with those of Brazil; (3) verify the avoided emissions by using non-petroleum based fuels, such as hydrated ethanol and CNG, and (4) propose strategies to reduce the emissions of those air pollutants.
Therefore, a bottom-up approach was applied, which allowed for the identification of the main conventional air pollutants emitted in the studied region, as well as the contribution of each category of road motor vehicles in emitting these pollutants.
This study is divided into 7 sections. In Section 2, the conventional air pollutants that are emitted by road motor vehicles are identified. Section 3 describes a general view of policies for reducing air pollutant emissions from road motor vehicles. The methodology used to estimate the emissions of air pollutants is described in Section 4. Section 5 introduces and discusses the results from the inventory of air pollutant emissions from road transportation in the state of Rio de Janeiro. In Section 6, the strategies used to reduce air pollutant emissions from road motor vehicles are listed. Finally, in Section 7 we show final considerations, limitations, and suggestions for further studies.
