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1

Zanieczyszczenie polichlorowanymi bifenolami [PCBs] gleby bylej bazy wojsk radzieckich

100%

Falandysz J. , Kawano M. , Brudnowska B. , Wakimoto T.

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nr 03

6-7

EN

Polychlorinated biphenyls (PCB-s) show high stability and a very low volatility. Industrial synthesis of these chemicals is very easy. In terms of technological science, they have excellent physical and chemical properties. Thanks to this, they were used on a large scale in a number of countries. In Russia for instance, they are being synthesised even today. Technological preparations of these compounds are the main source of PCBs related pollution. The article also provides information on testing soils samples taken in the former SU military base which has been contaminated with these pollutants.

PL

Polichlorowane bifenyle (PCBs) charakteryzuje duża stabilność oraz bardzo mała lotność. Łatwo je syntezować w skali przemysłowej. Cechują je doskonale z punktu widzenia techniki właściwości fizykochemiczne. Te cechy sprawiły, że stosowano je na dużą skalę w większości krajów. W Rosji są syntetyzowane do dziś. Głównym źródłem zanieczyszczenia środowiska chlorobifenylami są preparaty techniczne tych związków. Artykuł jest informacją o badaniach próbek gleby z terenu byłej bazy wojsk radzieckich, skażonej tymi substancjami.

2

Polichlorowane bifenyle i pestycydy chloroorganiczne w glebach w Polsce

100%

Kawano M. , Brudnowska B. , Falandysz J. , Wakimoto T.

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nr 1

15-28

PL

Określono stopień zanieczyszczenia pestycydami chloroorganicznymi (DDTs, HCHs, CHLs i HCBz) oraz chlorobifenylami (PC Bs) próbek gleb (0-10 cm) zebranych w 23 miejscowościach w Polsce w latach 1990-94. W analizie stosowano kapilarną chromatografię gazową z detektorem wychwytu elektronów (HRGC-ECD) oraz niskorozdzielczą spektrometrię mas (HRGC/LRMS). Wszystkie próbki gleby były skażone DDTs, PCBs i HCHs, a tylko w pojedynczych przypadkach nie wykazano skażenia HCBz i CHLs.

EN

The concentrations of organochlorine pesticides such as DDTs, HCHs, CHLs, HCBz and polychlorinated biphenyls (PCBs) were determined in 59 soil samples collected in Poland in 1990-1994 to understand the scale of contamination, spatial distribution and sources of these compounds. Identification and quantification of organochlorines were carried out using HRGC- ECD (63Ni) and HRGC-LRMS. All soil samples were contaminated by DDTs, PCBs and HCHs, while HCBz and CHLs were absent in a few samples. DDTs dominated as organochlorine residues in Polish soil and on the concentration of other insecticides was two orders of magnitude lower. Percentage composition of DDTs (about 60% of p,p'-DDT) indicates a very slow metabolism of DDT in Polish soils. Spatial distribution of HCHs in Poland is similar to distribution of DDTs, while HCBz and CHLs are rather evenly distributed. PCBs concentrations in soil of the Former Soviet Union Army Base are 10 times higher then in urban soils, and 100 times higher then in cultivated and forests soils.

3

Thermodynamic and physico-chemical descriptors of chloronaphthalenes: an attempt to select features explaining environmental behaviour and specific toxic effects of these compounds

63%

Falandysz J. , Puzyn T. , Szymanowska B. , Kawano M. , Markuszewski M. , Kaliszan R. , Skurski P. , Blazejowski J. , Wakimoto T.

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tom 10

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nr 4

EN

35 physico-chemical descriptors were used to characterize all 75 congeners of chloronaphthalene in terms of their environmental stability and specific dioxin-like toxicity. A prepared basic thermodynamic and physico-chemical property data matrix of PCNs was interpreted using Principal Component Analysis (PCA). The PCA of the thermodynamic and physico-chemical data matrix created a four-dimensional model that explained 76% (58% + 9% + 5% + 4%) of the total variance. The loading plot shows that the first PC is influenced by variables describing degree of chlorination, molecular weight, polarizability and lipophilicity. The best positively correlated descriptors are: retention time, standard molar entropy, heat capacity, a first-order molecular connectivity index, logarithm of octanol-water partition coefficient, the Wiener Index, specific polarizability, a third order shape index for molecules, the sum of absolute of the charges on each atom of the molecule, molecular weight, polarizability, refractivity, solvent-accessible surface, van der Waals surface, solvent-accessible volume, van der Waals volume. Negatively correlated descriptors are: standard enthalpy of formation and energy of HOMO. The second PC is strongly influenced by energy of LUMO, while substitution pattern parameters, number of chlorine atoms at a-positions and vicinal (adjacent) carbon atoms substitution pattern are less important parameters. The third PC depends on dipole moment and the largest negative charge, and on substitution at position 2 of naphthalene nuclei, while the symmetry group parameter is determined by PC4. There are small groups consisting of compounds which have similar values of LUMO energy and substitution pattern. The congeners of CN substituted with chlorine at positions 1, 2, 3, 6 and 7 (Fv/Fv PCN congeners), and next those substituted at positions 1, 2, 3 and 6 or 7 (Fr/Fv PCB congeners) are considered to be most potent in terms of dioxin-like toxicity, and followed by those substituted at four positions (Fr[Fv), at three positions (Tr/Fv) and so on. The thermodynamic stability of the congeners of CN depends on the number of attached chlorine and structure of the molecule. Among the 75 congeners of CN only a few, like PCN nos. 42, 560, 61, 66/67, are relatively resistant to biodegradation and biomagnify in animals occupying a higher position in the marine food web, and with a particular homologue group they are characterised by the lowest absolute values of energy of LUMO.