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A fim de determinar o impacto das emissões de aldeídos num aeroporto, sobre a qualidade do ar, foram determinadas as concentrações de acetaldeído e formaldeído nas áreas de pouso e decolagem do aeroporto nacional Santos-Dumont no Rio de Janeiro, Brazil. O aeroporto está localizado a aproximadamente 1 km do centro da cidade e, no ano de 2007, teve uma média de 70.000 pousos e decolagens. Foram coletadas 129 amostras no período de março a novembro de 2007. Para o formaldeído foram observadas concentrações no intervalo 2,6 a 10,3 µg m -3 e para o acetaldeído, no intervalo, 4,3 a 19,7 µg m -3 . Durante a manhã, as relações A/F (acetaldeído/ formaldeído, em unidades de massa) se encontraram no intervalo 0,7-1,0. Nos horários da tarde as concentrações de formaldeído foram menores e as de acetaldeído aumentaram. As concentrações de formaldeído e acetaldeído estão no mesmo intervalo que valores previamente obtidos para o centro da cidade e possivelmente não afetem a produção de ozônio a nível local.To estimate the impact of aldehyde emissions at an airport on the air quality, formaldehyde and acetaldehyde concentrations were measured in the idle and taxiway areas of the Santos-Dumont national airport in Rio de Janeiro. The airport is located about 1 km from downtown Rio de Janeiro and had an average of 70,000 landings and take-offs during 2007. A total of 129 samples were collected in the period from March to November 2007. Formaldehyde concentrations ranged from 2.6 to 10.3 µg m -3 , and acetaldehyde concentrations ranged from 4.3 to 19.7 µg m -3 . During the morning, A/F ratios (acetaldehyde/formaldehyde ratios, in mass units) were in the range 0.7-1.0. In the afternoon, formaldehyde concentrations were lower and acetaldehyde concentrations generally increased. Formaldehyde and acetaldehyde concentrations were in the same range than values previously published for downtown and may not affect ozone production in a local scale.Keywords: aircraft engine emissions, aldehydes, airport air quality IntroductionThe impact of aircraft emissions on air quality has been investigated in several recent studies. Perl et al. 1 estimated the emissions due to aircraft operations at a mid-sized French airport in 1987, 1990 and 1994 and suggested a perspective of future emissions under different scenarios. These results show that, currently, aircraft emissions may be considered negligible in comparison with those generated by surface transportation sources. However, in the long-term, aviation might be considered a growing air pollution problem.Literature data show that the critical stages for aircraft emissions are those when the aircraft is waiting on the ground (the taxi and idle phases). In these phases, aircraft engines do not operate at their optimum conditions and emit significant amounts of carbon monoxide and hydrocarbons. 2 Pison and Menut 2 presented a analysis modeling of the aircraft traffic emissions impact on the ozone concentrations over Paris. They used a volatile organic compound (VOC) speciation reported by the Europe...

Air samples were collected in three well characterized locations in the city of Rio de Janeiro, Brazil: downtown, the idle and taxi way areas of the national airport and an urban forest, where the main emissions are from vehicular, aircraft and biogenic sources, respectively. Aldehydes and BTEX concentrations show a characteristic profile which may be attributed to the emission sources. Formaldehyde/acetaldehyde ratios, in the early morning, were 1.39, 0.62 and 2.22 in downtown, airport and forest, respectively. Toluene/benzene ratios, for downtown, airport and forest areas, were 1.11, 1.82 and 1.06, respectively. The results show that the impact of the urban emissions on the forest is negligible as well as the impact of aircraft emissions over the urban area.