Polycyclic aromatic hydrocarbons (PAHs) concentrations in PM10 and PM2.5 particles were measured at 14 monitoring sites (12 for PM10 and 2 for PM2.5), located in the Metropolitan Area of Costa Rica, from January to November 2013. High-volume air samplers with pretreated quartz filters were used to collect the particles. The analytical determination was carried out using high-performance liquid chromatography (HPLC). The most abundant PAHs were benzo[a]anthracene, indeno(1,2,3-cd)pyrene, dibenz[a,h]anthracene and acenaphthylene. Ratios obtained by correlating the concentration of some PAHs, both PM10 and PM2.5, suggest that gasoline and diesel vehicles are the main sources in the area being studied. This is consistent with the results obtained when applying the positive matrix factorization (PMF) analysis, since vehicles accounted for 62–74% of total emissions in the area; burning wood fuel was the second source of emissions, contributing between 7 and 15%; and road dust was third, with almost 8%. | Se midieron las concentraciones de hidrocarburos aromáticos policíclicos (HAP) en partículas PM10 y PM2.5 en 14 sitios de monitoreo (12 para PM10 y 2 para PM2.5), ubicados en el Área Metropolitana de Costa Rica, de enero a noviembre de 2013. Alto volumen Se utilizaron muestreadores de aire con filtros de cuarzo pretratados para recoger las partículas. La determinación analítica se realizó mediante cromatografía líquida de alta resolución (HPLC). Los HAP más abundantes fueron benzo [a] antraceno, indeno (1,2,3-cd) pireno, dibenz [a, h] antraceno y acenaftileno. Los ratios obtenidos al correlacionar la concentración de algunos HAP, tanto de PM10 como de PM2,5, sugieren que los vehículos de gasolina y diésel son las principales fuentes en el área de estudio. Esto es consistente con los resultados obtenidos al aplicar el análisis de factorización matricial positiva (PMF), ya que los vehículos representaron 62-74% de las emisiones totales en el área; la quema de leña fue la segunda fuente de emisiones, contribuyendo entre el 7 y el 15%; y el polvo de la carretera ocupó el tercer lugar, con casi el 8%. | Universidad Nacional, Costa Rica | Laboratorio de Análisis Ambiental. Facultad de Ciencias Ambientales. Universidad Nacional, Costa Rica

Zeolitic tuff constitutes a technical and economical feasible alternative to manage acidic waters in initial phases of generation. A study of cation exchange with two zeolitic tuffs from Ecuador and one from Cuba has been conducted using breakthrough curve methodology. Cations Mn2+, Cd2+, Cr3+,Zn2+, and Al3+ have been chosen owing to their presence in underground water in exploration activities (decline development)in Fruta del Norte (Ecuador). Zeolites characterized by X-ray diffraction and thermal stability after heating overnight as heulandites show a similar exchange behavior for the five cations studied. The clinoptilolite sample Tasajeras shows a relevant cation exchange performance expressed in the important increment of spatial time to reach the breakthrough point in comparison with heulandite samples. The maximum length of unused beds was found for Cr3+ and Zn2+ cations showing,therefore, a lower adsorption performance in relation with Mn2+ and Cd2+. A final disposal method of metal-loaded zeolites with cement is proposed. Keywords Natural zeolites . Acidic mine waters . Cation exchange capacity . Cation saturation curves . Metal-loaded zeolites . Cement pozzolanic additives

This paper presents the main results of a study on the influence of driving style on fuel consumption and pollutant emissions of diesel passenger car in urban traffic. Driving styles (eco, normal or aggressive) patterns were based on the “eco-driving” criteria. The methodology is based on on-board emission measurements in real urban traffic in the city of Madrid. Five diesel passenger cars, have been tested. Through a statistical analysis, a Dynamic Performance Index was defined for diesel passenger cars. Likewise, the CO, NOX and HC emissions were compared for each driving style for the tested vehicles. Eco-driving reduces by 14% fuel consumption and CO2 emissions, but aggressive driving increase consumption by 40%. Aggressive driving increases NOX emission by more than 40%. CO and HC, show different trends, but being increased in eco-driving style.