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1

GC–Mass determination of low levels polychlorinated dibenzodioxin and polychlorinated dibenzofuran in beach sand and marine sediment of the Gulf of Aqaba

Yanes Q., Rasheed M.

Acta Chromatographica

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2018

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Vol. 30, no. 1

38--42

EN

The levels of persistent organic pollutants (POPs) from industrial by-products were determined in beach sand and marine sediments from different sites along the Jordanian coast of the Gulf of Aqaba. Seventeen polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-p-furans (PCDD/Fs) compounds were identified. Automatic Soxhlet (Soxtec) extraction method was used for PCDD/Fs extractions using toluene as a solvent. Pre-washed multilayer silica gel column was used for cleanup step. Samples were analyzed using high-resolution gas chromatography and mass spectroscopy detector (HRGC–MS). Low levels of POPs were found in all sand and sediment samples. Concentrations of PCDD/Fs ranged between 3.91 and 8.91 ng kg−1 dw with an average of 6.49 ng kg−1 dw for beach sand samples and between 6.560 and 45.95 ng kg−1 dw with an average of 28.70 ng kg−1 dw for marine sediment samples. Concentrations of PCDD/Fs for soil and sediment were mostly less than other sites worldwide. PCDD/Fs concentrations measured in this study can be considered as a baseline for future monitoring and control of PCDD/Fs as requested by Stockholm Convention.

2

Effect of selected additions on de novo synthesis of polychlorinated dioxins and furans

Wielgosiński G., Namiecińska O., Łechtańska P., Grochowalski A.

Ecological Chemistry and Engineering. S

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2016

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Vol. 23, nr 2

249--257

EN

Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans are generally considered the most dangerous chemical substances known to man. Although they have never been the product of purposeful human activity, yet they are formed in many chemical and virtually all thermal processes. Research on the occurrence of dioxins in the environment, their release into the environment, ways of formation and methods of reducing their emissions lasts since the late seventies of the last century. Currently, we know three basic pathways of dioxins formation in thermal processes, the most important of them being the so called de novo synthesis which occurs outside the combustion zone at 200-400°C in the presence of catalysts (eg copper) and oxygen from the products of incomplete combustion including carbon black and chlorine or chlorinated compounds. It is well known that some metals like copper catalyze the de novo synthesis, while others decompose dioxins and furans formed previously. The formation of dioxins resulting from the de novo synthesis was studied through analysis of the effect of the type of metal on the course of the de novo synthesis. The influence of the addition of sulfur, nitrogen and alkali metals on this synthesis was also examined because some reports in the literature refer to inhibitory effect of these elements.

3

Evaluation of the recombinant cell-based bioassay as a screening method for PCDD/Fs monitoring in fish tissue

Stypula-Trebas S., Warenik M., Gembal M., Malagocki P., Piskorska-Pliszczynska J.

Environmental Biotechnology

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2009

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Vol. 5, No. 1

32-41

EN

Among 210 congeners only 17 highly toxic, 2,3,7,8-chlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) are of toxicological concern. They exhibit high binding affinity to an intracellular aryl hydrocarbon receptor (AhR), causing harmful effects at exposure levels of thousands of times lower than most environmental toxicants. The Chemically Activated LUciferase gene expression bioassay (CALUX) utilizes recombinant cells that were transfected with a luciferase reporter gene, which responds to dioxin-like compounds with the induction of luciferase in a time-, dose-, AhR-dependent and chemical-specific manner. The bioassay evaluation concerning the European Community (EC) requirements for the PCDD/Fs determination for the official control of foodstuffs was performed on salmon tissue. In order to evaluate the bioassay performance characteristics, recovery range, limit of detection (LOD), limit of quantification (LOQ) and precision were determined. The results revealed that combining a dichloromethane: hexane extraction, an acid silica plus activated carbon clean-up provides reliable, reproducible (CV = 9-20%) measurements with acceptable recovery (78%) and sensitivity at the required ppt range. Due to the low cost and high throughput characteristics of the CALUX assay, food monitoring for PCDD/Fs may benefit from use of this bioassay as a prescreening tool to select and prioritize samples for subsequent analysis by high resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS). Although the bioassay may not be able to specify identity of the reactive substances, it may serve as a very useful tool for the evaluation of contamination sources.

4

Utlenianie mieszaniny aceton-woda (1:5) zawierającej kwas 2,4-dichlorofenoksyoctowy z udziałem katalizatora monolitycznego platynowo-rodowego

Żarczyński A., Gorzka Z., Zaborowski M., Kaźmierczak M., Ciesielski R.

Ecological Chemistry and Engineering. S

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2009

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Vol. 16, nr 1

107-113

PL

Przedmiot badań stanowiły: modelowa mieszanina aceton-woda (1:5), zawierająca kwas 2,4-dichlorofenoksyoctowy (kwas 2,4-0) o stężeniu 2,5 g/dm3, oraz sama mieszanina aceton-woda. Natężenie przepływu powietrza wynosiło 0,215 m31h, natężenie dozowania substratu 32,5 g/h, czas kontaktu 0,36 s oraz zakres temperatury badań 400_650°C. Stosowano katalizator monolityczny platynowo-rodowy (Pt - 0,09% i Rh - 0,04% na warstwie pośredniej z y-Al2O3 naniesionej na kordieryt). Stopień konwersji TOC (OWO) ciekłych produktów reakcji względem roztworu utlenianego był większy od 99% w całym badanym zakresie temperatury. Zawartość dioksyn w spalinach z reakcji utleniania kwasu 2,4-D w temperaturze 550°C, wyznaczonej jako optymalna, wyniosła 0,0213 ng TEQ/m3. Była więc znacznie mniejsza od wartości dopuszczalnej równoważnika toksyczności równej 0,1 ng TEQ/m3.

EN

The subject of the investigation was the mixture of acetone-water (1:5) and a model solution of 2,4-D acid at the concentration of 2.5 g/dm3 in this mixture. Air flow rate was 0.215 m3/h and dose rate of the substrate was 32.5 g/dm3. The contact time was 0.36 s and the temperature ranged from 400 to 650°C. Monolithic platinum-rhodium catalyst (Pt - 0.09% and Rh - 0.04%) at an intermediate layer with y-Al2O3 deposited on cordierite, was applied in the experiments. The substrates oxidation proceeded efficiently because the TOC conversion of liquid reaction products in relation to the oxidized solution was higher than 99% in the tested temperature range. The content of PCDD/Fs in the combustion gases from the oxidation of 2,4-D acid in the optimum temperature of 550°C was 0.0213 ng TEQ/m3. This value is lower than the admissible value of the toxicity equivalent which is 0.1 ng TEQ/m3.

5

Utlenianie kwasu 2,4-dichlorofenoksyoctowego z udziałem katalizatora monolitycznego

Żarczyński A., Gorzka Z., Zaborowski M., Kaźmierczak M., Ciesielski R.

Proceedings of ECOpole

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2007

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Vol. 1, No. 1/2

283--287

PL

Przedmiot badań stanowiły: roztwór modelowy kwasu 2.4-dichlorofenoksyoctowego (kwas 2,4-D) o stężeniu 2,5 g/dm3 w mieszaninie aceton-woda (1:5) oraz sama mieszanina aceton-woda. Natężenie przepływu powietrza wynosiło 215 dm3/h natężenie dozowania substratu 32,5 g/h, czas kontaktu 0,36 s oraz zakres temperatury badań 400÷650°C. Stosowano katalizator monolityczny plalynowo-rodowy (Pt - 0,09% i Rh - 0.04% na warstwie pośredniej z ɣ-A2O3 naniesionej na kordieryt). Stopień konwersji TOC (OWO) ciekłych produktów reakcji względem roztworu utlenianego był wyższy od 99% w całym badanym zakresie temperatury. Zawartość dioksyn w spalinach z reakcji utleniania kwasu 2,4-D w temperaturze 550°C, wyznaczonej jako optymalna wyniosła 0.0213 ng TEQ/m3. Była więc znacznie mniejsza od wartości dopuszczalnej równoważnika toksyczności równej 0,1 ng TEQ/m3.

EN

The subject of the investigation was the mixture of acetone-water (1:5) and a model solution of 2,4-D acid at the concentration of 2.5 g/dm3 in this mixture. Air flow rate was 215 dm3/h and dose rate of the substrate was 32.5 g/dm3. The contact time was 0.36 s and the temperature ranged from 400 to 650°C. Monolithic platinum-rhodium catalyst (Pt - 0.09% and Rh - 0.04%) at an intermediate layer with ɣ-Al2O3 deposited at cordierite, was applied in the experiments. The substrates oxidation proceeded efficiently because the TOC conversion of liquid reaction products in relation to the oxidized solution was higher than 99% in the tested temperature range. The content of PCDD/Fs in the combustion gases from the oxidation of 2,4-D acid in the optimum temperature of 550°C was 0.0213 ng TEQ/m3. This value is lower than the admissible value of the toxicity equivalent which totals 0.1 ng TEQ/m3.

6

Emissions from waste incineration plants - primary methods of emission reduction

Wielgosiński G.

Polityka Energetyczna

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2003

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T. 6, spec. [1]

131-140

EN

Products of incomplete waste incineration identified on the basis of investigations carried out in the real waste incineration systems, the mechanism of formation of some of them and primary methods for emission reduction are discussed in the paper. It was shown that preservation of good incineration conditions which are similar to those of complete incineration, enables a significant reduction of emission of many pollutants to the atmosphere.

PL

W artykule omówiono produkty niecałkowitego spalania odpadów zidentyfikowane na podstawie badań prowadzonych w rzeczywistych zakładach spalania odpadów, mechanizm tworzenia się niektórych z nich oraz podstawowe metody redukcji emisji. Pokazano, że zachowanie dobrych warunków spalania, zbli- żonych do warunków wymaganych dla całkowitego spalania, umożliwia znaczącą redukcję emisji wielu zanieczyszczeń do atmosfery.