| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 4428453 | Science of The Total Environment | 2014 | 8 Pages |
•PCDD/F and dl-PCB concentrations were measured at four urban locations of the densely populated Andean city of Manizales.•Manizales has an Andean forest climate with high vehicular density and relatively low wind velocity.•Concentrations of passive samples are more associated with industrial source areas.•Concentrations in particle phase (PM10) are more associated with mainly vehicular source areas.•Results obtained are the first data from passive monitoring in urban zones of Colombia.
Concentration gradients were observed in gas and particulate phases of PCDD/F originating from industrial and vehicular sources in the densely populated tropical Andean city of Manizales, using passive and active air samplers. Preliminary results suggest greater concentrations of dl-PCB in the mostly gaseous fraction (using quarterly passive samplers) and greater concentrations of PCDD/F in the mostly particle fraction (using daily active samplers). Dioxin-like PCB predominance was associated with the semi-volatility property, which depends on ambient temperature. Slight variations of ambient temperature in Manizales during the sampling period (15 °C–27 °C) may have triggered higher concentrations in all passive samples.This was the first passive air sampling monitoring of PCDD/F conducted in an urban area of Colombia. Passive sampling revealed that PCDD/F in combination with dioxin-like PCB ranged from 16 WHO-TEQ2005/m3 near industrial sources to 7 WHO-TEQ2005/m3 in an intermediate zone—a reduction of 56% over 2.8 km. Active sampling of particulate phase PCDD/F and dl-PCB were analyzed in PM10 samples. PCDD/F combined with dl-PCB ranged from 46 WHO-TEQ2005/m3 near vehicular sources to 8 WHO-TEQ2005/m3 in the same intermediate zone, a reduction of 83% over 2.6 km. Toxic equivalent quantities in both PCDD/F and dl-PCB decreased toward an intermediate zone of the city.Variations in congener profiles were consistent with variations expected from nearby sources, such as a secondary metallurgy plant, areas of concentrated vehicular emissions and a municipal solid waste incinerator (MSWI). These variations in congener profile measurements of dioxins and dl-PCBs in passive and active samples can be partly explained by congener variations expected from the various sources.
