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Abstract: Vehicular fleet forecasting has a strategic value for governmental planning management and assessment, for economic policies and environmental programs, but particularly to estimate future emission inventories and fuel demand projections. In order to determine the forecasts of detailed vehicular fleets, those comprise the overall car stock and their associated pollutant emissions and fuel demand, specific curves of retirement models were used in addition to econometric analysis. To obtain forecasts for the year 2015, this methodology was applied to the Mexico City Metropolitan Area case using data since 1990. The validation of the models applied was done through economic data from 2004, 2006 and 2008. The results of the forecasts carried out displayed high confidence levels, above 95% for the medium term. The exercise with the forecasted fleets produced an expected increase of around 21% of criteria pollutants and 31% in greenhouse gases emissions due to vehicular activity, from 2007 to 2015. Further, an increase in fuel demand of around 22.9% gasoline and 27.1% diesel in the same period was estimated, which are lower than those officially projected. Finally, a specific coefficient β to the Gompertz equation applied to Mexico City case was obtained. [Copyright &y& Elsevier]

Human remains and corpses' cremation is an increasing practice worldwide alternative to burials, which have increased their cost and reduced spaces in cemeteries. Alike to other combustion processes, cremation produces pollutant emissions that contribute to worsen air quality in modern cities. A 6-month sampling campaign was performed in order to characterize emissions from corpse cremation in three different crematorium ovens and develop emission factors which were used to determine the population exposure to those pollutants during cremation activities applying a dispersion model. The main difference among crematoria was the inclusion or non-inclusion of controlled air supply devices. Using isokinetic samplings in the chimneys crematoria, emissions were measured and characterized with different chemical analyses. No significant differences were found in arsenic and metal concentrations among different crematories, although carbon monoxide, particles, elemental carbon, organic carbon, and polycyclic aromatic hydrocarbon concentrations in facilities without controlled air supply were up to seven times higher than those with controlled air supply. Nevertheless, these pollutants exceeded standards in all crematoria. Except for elemental and organic carbon concentration that correlated with corpse weight, other recorded cadaver characteristics bear no relation with pollutant emissions. Emission factors among different ovens did not present significant differences; then, they were used for dispersion modeling of particles and mercury emissions over Mexico City when 35 crematoria operate simultaneously through an hour showing that PM 2.5 and Hg increase 0.01-1 μg m -3 and 0.01-0.1 ng m -3 , respectively, in that scenario.