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Two sets of experiments were performed for collected particulate mass emitted directly from the exhaust of diesel engines burning diesel and biodiesel fuels: First, a diesel truck was used in the field, and in the second test, a similar diesel engine was used in the laboratory. The mass of particles and polycyclic aromatic hydrocarbons (PAH) was determined. No reduction was observed in the mass of particles per min using biodiesel relative to that produced when burning diesel. Pyrene and phenanthrene showed the highest mass concentrations in diesel and biodiesel in both tests. Reductions in these PAHs greater than 80% (in the truck field test) and 35% AE 11% (in the engine laboratory test) were observed when using biodiesel in any mixture thereof, with respect to diesel. The mean AE standard deviation of the ratios of BaA/(BaA þ Chry) and (BbF þ BkF)BghiP for diesel emissions were consistent with the literature. Four ratios amongst PAHs were proposed, with relative standard deviation < 10%, which suggests that these ratios could be used as emission markers for diesel and animal biodiesel blends (

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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.