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Endocrine-disrupting chemicals (EDC) are manmade or natural chemicals that have the ability to interfere with the endocrine system of animals. They have not been monitored systematically in the Czech Republic. The goal of the present study was the characterization of aquatic environmental pollution from the Brno (Czech Republic) city agglomeration focusing on EDC. Passive sampling devices, as well as semipermeable membrane devices (SPMD) and polar organic chemical integrative samplers (POCIS), were used for the pilot assessment of EDC. They were deployed for 21- to 28-d periods at nine locations in the Svratka and Svitava Rivers, Brno, Czech Republic, including at the inlet and outlet of Brno's wastewater treatment plant. The SPMDs were used to monitor nonpolar compounds such as polychlorinated biphenyls (PCBs), polynuclear aromatic hydrocarbons (PAHs), and organochlorinated pesticides (OCP). The POCIS were used to monitor polar compounds such as pesticides and their metabolites, perfluoro-organic compounds (PFOC), and pharmaceuticals. The passive samplers allowed very low detection limits for soluble (bioavailable) fractions of pollutants. The contribution of PAH, PCB, and HCB in sewage water to pollution of the Svratka River was low. The Brno wastewater treatment plant was identified as the main source of pharmaceuticals, triclosan, methyl triclosan, and some polar pesticides.

Five different boiler types (automatic boiler, overfire boiler, boiler with down-draft combustion, and two types of gasification boilers) representing residential-scale combustion technology were tested. Boilers were fueled with various fuels (lignite, wet and dry wood, wood pellets, and mixed fuel), and the combustion emissions were measured both at nominal and reduced output. The investigated emissions comprised CO, organic gaseous compounds (OGC), and particulate matter (PM). A cyclone and a low-pressure impactor were used to determine PM emissions. It was found that the emission factors for CO, OGC, and PM depend more on boiler type and mode of operation (reduced or nominal output) than on fuel type. Data from the Dekati low-pressure impactor (DLPI) show that, in most cases, PM1 represents approximately 80% of the total PM mass. PM0.1 represents 15–30% (modern boilers) or 5–10% (old-type boilers) of the total PM mass. Comparison of the results shows that the emission factors for PM obtained by the cyclone were higher than the emission factors obtained using the DLPI.

Ashes were prepared by annealing selected types of solid fuels (biomass: corn cobs, sunflower husks, olive pomace, hay pellets and rice husks; coal: lignite and bituminous; and alternative fuel: paper sludge) at different temperatures (550°C, 815°C and 975°C). Based on X-ray fluorescence spectra, the slagging/fouling indexes were used to study the effects of the type of ash and the ashing temperature on the ash fouling and slagging properties. Slagging indexes were compared with the ash fusion temperatures. Ash fusion temperatures were measured by a LECO AF-700. The lowest deformation temperature (below 1000°C) was seen for the ashes prepared from hay pellets and corn cobs. On the other hand, the deformation temperature exceeded 1500°C for ashes prepared from paper sludge, sunflower husks and rice husks. By calculating the different slagging/fouling indexes, all the ashes exhibited slagging/fouling problems of varying degrees.

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Summary. Effect of column bleed on trueness of determination of trace levels of dibenzofuranes (PCDD/F) and biphenyls (PCB) by gas chromatography-high-resolution mass spectrometry (GC-HRMS) was studied. As a result of extensive bleed of an arylenesiloxane capillary column, fluctuations of abundance ratios of monitored ions were observed, making exact determination of target analytes impossible. These effects were observed on food samples as well as on pure standard mixtures. The column bleed affected the abundance ratios of PCDD/F and PCB within the range of 13-328 pg of target analyte/mL, and higher levels of analytes remained intact. An analysis of diluted calibration mixtures is recommended as a tool for detection of column bleed.