Degradation pathways of pentachlorophenol and benzo(a)pyrene during heterogeneous photocatalysis.

Organic micropollutants, in particular those of anthropogenic origin, may have a toxic influence on water organisms. Photochemical oxidation processes are one of the most effective methods of decomposition of a wide range of those compounds. During the oxidation process a large number of different by-products are generated, which can still be biologically active. The development of analytical techniques, including the reduction of the detection limit to several fg/L, allows the identification of even trace concentrations of compounds. The paper presents the determination of pentachlorophenol and benzo(a)pyrene degradation pathways during the process of heterogeneous photocatalysis carried out in the presence of titanium dioxide. The gas chromatography-mass spectrometry (GC-MS) analysis of post-processing samples indicated the formation of different by-products of the parent micropollutants. Moreover, the toxicity assessment demonstrates for both tested micropollutants an increase in the toxicity within the whole time of the UV irradiation process run.

Characterization of three new alleles HLA-A*02:241, HLA-A*02:242 and HLA-A*30:04:02.

We describe three novel alleles HLA-A*02:241, HLA-A*02:242 and HLA-A*30:04:02.

The potential of the organic micropollutants emission from swimming accessories into pool water.

The potential leaching of organic micropollutants from swimming accessories was studied in the laboratory experiment. Seventeen different swimming accessories have been placed in various water matrices under different conditions in order to reproduce the actual environmental conditions of swimming pool water. The presence of micropollutants in water samples, after the exposure of swimming accessories, was assessed using indirect indicators (Total Organic Carbon and Phenol Index) and directly using a gas chromatograph coupled with a mass spectrometer with electron ionization. A wide range of organic compounds emitted from swimming accessories have been identified. The most common in tested samples was isophorone. The frequency of its occurrence in 50 swimming pools located in Poland was equal to 89% in concentrations ranged from 0.75 to 1.01 µg L-1 (below the concentration of 40 µg L-1, which is estimated to increase the cancer risk). Content of combined chlorine (1.52-3.16 mgCl2 L-1) in chlorinated matrices indicated a high potential for disinfection by products (DBPs) formation from organic matter emitted into pool water from swimming accessories. Ten of seventeen tested samples showed the toxic effect, measured as the bioluminescence inhibition of bacteria Aliivibrio fischeri.