Alec F. Gaines

The pollution status and the toxicity of surface sediments in İzmit Bay (Marmara Sea), Turkey

Izmit Bay is one of the most polluted and populated enclosed sea in Turkey. It has been the centre of industrial activities for the last 30 years. Seven major sources enter the bay waters along the north coastline of the bay. This investigation forms part of continuing ecotoxicology studies in the Izmit Bay designed to constrain and minimise the pollution caused by flourishing industry and a growing population. Sediments sampled from the mouths of the major discharges of Izmit Bay were analysed for their organic carbon, total polycyclic aromatic hydrocarbon (t-PAH) and trace inorganic element (Cd, Al, As, Pb, Hg and Cu) contents and compared with those found in the sediments from the reference station in the outer bay (in the Marmara Sea). The toxicity of sediments was determined in the bulk and elutriate samples by using algal (Phaeodactylum tricornutum) batch bioassays. Chemical data showed that the sediments collected from the inner sites of the bay have been contaminated with Cd, Hg, As and PAHs. Organic carbon contents were also found higher. All the major industrial discharges into the bay are now biologically treated but bioassays performed with bulk sediments revealed that the recent sediments are toxic to the microalgae throughout the bay. The results are consistent with the previous toxicity studies performed with the industrial discharges.

The chemical composition of Black Sea suspended particulate organic matter : pyrolysis-GC/MS as a complementary tool to traditional oceanographic analyses

Abstract A “traditional” description of the abundance and chemical composition of suspended particulate organic matter (POM) in open and coastal waters of the southern Black Sea in June 1996 has been confirmed and extended by pyrolysis–gas chromatography/mass spectrometry (Py-GC/MS) analyses. Py-GC/MS provided depth profiles of the relative concentrations of twenty three marker compounds characteristic of chlorophylls (CHL), lipids, carbohydrates (CBH) and proteins produced by thermal degradation of the POM retained on the filters. No terrestrial markers, characteristic of lignin or of plant waxes, were observed. Evidence was found for considerable changes in the chemical composition of POM in the water column from the surface down to the sulphidic water layer. In surface-mixed layer, both POC:CHL-a ratios and relative abundances of CBH markers were notably high, suggesting that the suspended POM was mainly composed of detritus. The profiles of both CHL and protein markers exhibit coherent maxima at the base of the euphotic zone, coinciding with the nutricline depth in the central cyclonic eddy, where the bulk POM possessed relatively low C:N ratios. Beneath the 0.1% light depth the absence of intact phytoplankton cells and the presence of bacteria and faecal pellets was accompanied by a change in the protein composition of the POM as shown by the changes in the ratio of pyrrole:indole markers. Lipid markers increased markedly from the euphotic zone into the oxycline and remained almost constant in the suboxic waters; they then decreased in the sulphidic interface, presumably due to consumption of lipids by anaerobic bacteria.

Biomarkers of marine pollution observed in species of mullet living in two eastern Mediterranean harbours

The activities of enzymes associated with xenobiotic metabolism and or oxidative processes, and the levels of aromatic DNA adducts, have been determined in the livers of grey mullet Oedalechilus labeo and Lisa ramada living in two eastern Mediterranean harbours. Glutathione peroxidase GSH P activity was 2.5 times higher 9 IU g-1 liver and glutathione reductase GSSG R activity was twice as high 2.5 IU g-1 liver in fish from the more polluted harbour at Mersin than in the harbour near Erdemli. Superoxide dismutase SOD activity was 25 lower 4.3 IU g-1 liver in the more polluted harbour. The concentrations of glutathione and malondialdehyde varied both with species and environment by a factor of 2.5-3. DNA adducts in liver were determined by 32P postlabelling. In Oedalechilus labeo in the more polluted harbour, adduct levels were 258 21 adducts per 108 nucleotides mean SE; two groups of Lisa ramada were distinguished having 261 48 and 30 6 adducts per 108 nucleotides, respectively. The average adduct level in a group of mullet of mixed species in the less polluted harbour was 3.3 2.3 adducts per 108 nucleotides. The results illuminate the ability of mullet to live in contaminated marine environments, and show that enzyme activities and liver DNA adduct levels can serve as indicators of marine pollution.The activities of enzymes associated with xenobiotic metabolism and or oxidative processes, and the levels of aromatic DNA adducts, have been determined in the livers of grey mullet Oedalechilus labeo and Lisa ramada living in two eastern Mediterranean harbours. Glutathione peroxidase GSH P activity was 2.5 times higher 9 IU g-1 liver and glutathione reductase GSSG R activity was twice as high 2.5 IU g-1 liver in fish from the more polluted harbour at Mersin than in the harbour near Erdemli. Superoxide dismutase SOD activity was 25 lower 4.3 IU g-1 liver in the more polluted harbour. The concentrations of glutathione and malondialdehyde varied both with species and environment by a factor of 2.5-3. DNA adducts in liver were determined by 32P postlabelling. In Oedalechilus labeo in the more polluted harbour, adduct levels were 258 21 adducts per 108 nucleotides mean SE; two groups of Lisa ramada were distinguished having 261 48 and 30 6 adducts per 108 nucleotides, respectively. The average adduct level in...

Comparison of fast atom bombardment mass spectrometry and size exclusion chromatography in defining high molecular masses in coal-derived materials

Abstract The detection by fast atom bombardment mass spectrometry (f.a.b.-m.s.) of high molecular mass (greater than 1000 Da) material in coal-derived products was investigated. The pentane insoluble (PI) fractions of liquefaction extracts from maceral concentrates of two UK coals (Linby and Cortonwood), prepared in a low-residence time (less than 10 s) flowing-solvent reactor and fractions of hydropyrolysis tar prepared in a hot-rod reactor at 500 °C were examined.F.a.b.-m.s. spectra of the Cortonwood liptinite concentrate liquefaction extract PI-fraction mounted in a thiodiethanol matrix indicated ions up to molecular masses of about 4000 Da. This appears to be the highest reported molecular mass identified by fast atom bombardment in a coal-derived material. Other liquefaction extract PI-fractions showed somewhat lower molecular masses. The phenolic, basic nitrogen and aromatic fractions of the hydropyrolysis tar indicated ionization up to molecular mass limits between 1500 and 2000 Da. Comparison of these results with size exclusion chromatography (s.e.c.) showed agreement with results for the hydropyrolysis tar fractions; however, the presence of molecular masses in excess of 10000 Da was indicated by s.e.c. for the liquefaction extract PI-fractions. Not all problems associated with vaporization, ionization and detection of high molecular mass materials in f.a.b.-m.s. appear to have been solved, with the choice (polarity) and preparation of matrices for sample mounting remaining an empirical procedure.

Nuclear magnetic resonance spectra of two reductively ethylated fuels

Abstract A lignite (67.2% C daf) and a coal (89.0% C daf) have been reductively ethylated by Sternbergs procedure 4 and the spectra, in particular the 1 H and 13 C n.m.r. spectra, of the products have been obtained. The distribution of hydrogen atoms and, in less detail, of carbon atoms in the reductively ethylated fuels has been determined. It is emphasized that both reductively ethylated fuels contained a variety of structures. The carbon aromaticities of the reductively ethylated lignite and the reductively ethylated coal were 0.41 ± 0.08 and 0.40 − 0.54 respectively. The aromatic nuclei of the reductively ethylated coal were more highly substituted than those of the reductively ethylated lignite. The 1 H n.m.r. spectra indicate that the reductively ethylated coal and lignite possessed ≈3.5 and ≈2.5 substituents per benzene ring respectively. Resolved absorption in the 13 C n.m.r. spectra suggests lower figures than these and it was evident that some of the benzene rings in both materials but especially in the reductively ethylated lignite were lightly substituted. The 13 C n.m.r. spectra show that both materials contained branched and unbranched paraffin chains. Much of the 13 C n.m.r. spectra however consisted of unresolved absorptions and the 13 C n.m.r. measurements suggest that the reductively ethylated materials consisted of rigid, relatively immobile molecules of moderate molecular weight. 13 C n.m.r. absorption by carbon atoms adjacent to aromatic rings was amongst that which was not resolved — though the rings themselves gave resolved absorptions — and this suggests that the aromatic rings were on the periphery of a rigid, perhaps alicyclic, structure.

Pyridine extracts of solid fuels

Abstract Pyridine extracts of a coking coal and of two lignites have been further separated and the 1H and 13C n.m.r. spectra of the various fractions have been recorded. Three methods of separation were investigated: gel-permeation chromatography, successive extraction with petroleum ether and with benzene as used by previous workers for supercritical-gas extracts, and the classical extraction of the fractions. Gel-permeation chromatography gave most promise of effective separation but the fractions obtained often contained too little material to give n.m.r. spectra. The n.m.r. spectra of the chloroform-soluble material from the pyridine extracts of the coking coal were consistent with a material consisting of polynuclear aromatic nuclei joined through simple bridge structures and possibly also through direct carbon—carbon linkages. The nuclei were substituted by branched and unbranched paraffin chains, some of which were 7 or 8 carbon atoms long. It is probable that alicyclic structures were also present. The aromatic nuclei were mobile in solution. 60% of the carbon atoms were aromatic, and it can therefore be calculated that the molecular weight per aromatic nucleus was 200–300. It is suggested that 13C n.m.r. spectra may be used to characterize chemicals likely to confer coking properties on solid fuels.

Pyrolysis of deuterated and reduced coals

Abstract Samples of a coal and a lignite were boiled in pyridine, partially reduced and partially deuterated by modified Birch reductions. These samples were slowly pyrolysed in an inert atmosphere in a horizontal tube furnace to temperatures in the range 300–600 °C. The yields and the nature of the products are reported; in particular an attempt is made to characterize the various tars, and the pyrolyses are described in terms of a simplified mechanism. It was found that boiling the fuels in pyridine increased the subsequent yield of tar and increased the proportion of high-boiling material within the tar. Tar formation was diffusion-controlled. The role of hydrogen atoms from the hydroaromatic structure of the fuels in the formation of tar, liquor and gas was confirmed. Experiments with partially deuterated fuels established that during pyrolysis interchange of hydrogen atoms occurred amongst the molecules of the gas. Further pyrolyses of partially deuterated coals under wider conditions should be profitable.

Mild oxidation of reductively ethylated solid fuels

Abstract A reductively ethylated lignite and a reductively ethylated coking coal have been oxidized by alkaline nitrobenzene. The products of the oxidation were separated into fractions by extraction with organic solvents, and the compounds present in the resulting solutions were characterized by a combination of gas chromatography and mass spectrometry. These compounds had molecular weights less than 300 and the oxidation, though mild, had fragmented the reductively ethylated fuels. Many problems remain, but the method appears to lead to an understanding of the structures of reductively ethylated solid fuels. The structures of the oxidation products are listed and discussed; in general they confirm the interpretation of the n.m.r. spectra of reductively ethylated solid fuels 2 .

Differences between blood and liver aromatic DNA adduct formation

Aromatic DNA adducts in the livers and blood of grey mullet (Mugil sp.) have been monitored between 1993 and 1996 by the isolation of DNA and the postlabeling of the DNA adducts with 32P. The grey mullet were sampled from three well-characterised harbours, two in the northeastern Mediterranean and one in the northeastern Black Sea near Trabzon close to a site of aquaculture. One of the northeastern Mediterranean harbours was highly polluted with polynuclear aromatic hydrocarbons (PAHs) and was rich in inorganic nutrients. Larger grey mullet lived in this harbour than the other harbours and their livers possessed approximately 100 aromatic DNA adducts per 10(8) nucleotides. The livers from grey mullet in the other two harbours possessed < or = 25 aromatic DNA adducts per 10(8) nucleotides but these concentrations depended on a variety of factors. Blood cell being regenerated more rapidly than liver cells, it is found that generally the ratio of DNA adduct concentrations in piscine liver and blood will increase with the pollution of the surrounding marine environment. Fishes are acceptable models for the metabolism of xenobiotics and the associated formation of harmful aromatic DNA adducts in organisms.

Reductive ethylation in ethereal solvents

Abstract Organic compounds, in particular anthracene and naphthalene, and two coals have been reductively ethylated in tetrahydrofuran (THF) and diglyme using alkali metals to form anions and ethyl iodide to produce ethylates. Product distributions were sensitive to experimental conditions. The rate of anion formation was controlled by their rate of desorption, probably as contact ion pairs, from the alkali metal surface. The enthalpy of formation of a solvated contact ion pair was ≈500 kJ mole −1 mainly due to dipole-solvent interaction. 18-crown-6 ether was used to diagnose that, when treated with potassium in THF, anthracepe gave solvated contact ion pairs and probably di-anions whose reactions were characterized by the formation of ethyldihydroanthracene. Naphthalene under identical conditions gave loosely solvated mono-anions which reacted by electron transfer to give diethyldihydronaphthalene. With other alkali metals anthracene and naphthalene gave similar product distributions. The behaviour of other polynuclear aromatic hydrocarbons and of two coals was classified in the same way. It is suggested that when coals are readily solubilized by reductive alkylation mono-alkyldihydro products will predominate.