The content of polycyclic aromatic hydrocarbons (PAHs) in water and sediments of the Blachownia

reservoir (South Poland) was investigated. Spatial variability of PAH concentrations in the longitudinal profi le of the

tank was determined. PAHs in samples were determined by gas chromatography coupled with mass spectrometric

detection (GC-MS QP-2010 Plus Shimadzu) using an internal standard. Concentrations ranged from 0.103 μg/L to

2.667 μg/L (Σ16 PAHs) in water samples and from 2.329 mg/kg d.w. to 9.078 mg/kg d.w. (Σ16 PAHs) in sediment

samples. A pollution balance was calculated and it was estimated that the infl ow load was 17.70 kg PAHs during

the year and the outfl ow load was 9.30 kg PAHs per year. Accumulation of about 50% of the annual PAH loads

(8.90 kg) is a threat to the ecological condition of the ecosystem. It was calculated that the PAH loads in bottom

sediment were about 80 kg, which limits their economic use. Improvement of the ecological status of this type of

reservoir can be achieved by removing the sediment. Analysis of the diagnostic ratios obtained for selected PAHs

showed that the potential sources of PAH emissions in small agricultural – forest catchments can be combustion

of a coal, wood, plant material (low emission, forest fi res, burning grass, etc.). Transportation is also signifi cant.