The determination and environmental significance of planar aromatic compounds in the marine environment.

The objective of the thesis was to determine the importance of three groups of planar aromatic compounds to the marine environment. The groups comprised chlorobiphenyls (CBs), polychlorinated dioxins and -furans (PCDD/Fs) and polycyclic aromatic hydrocarbons (PAHs). Previous studies on toxicity, occurrence, origins and methods of analysis were reviewed, and methods of analysis for the determination of planar aromatic compounds were developed, adapted and compared. The evaluation of existing and developed methodology led to a selection of methods applied to a field study in the Firth of Clyde. The reproducibility and bias of the analytical methods were determined. The concentration of CBs, PCDD/Fs and PAHs in sediments and of CBs in mussels and plaice were determined in the Firth of Clyde. Pattern analysis and normalisation to particle size and total organic carbon identified 5 regions of sediments with different levels and patterns of planar aromatic compounds. The patterns and levels at the three disposal sites of sewage sludge and dredge spoils were different from each other and the remaining sites. The patterns occurring at sites close to the disposal sites were similar to each other although no geographical relation existed between these sites. The patterns of the stations located at distances of >10 km from the disposal sites were not directly related to those occurring on disposal sites. The concentrations of CBs in biota were discussed in relation to the Log K ow of the congener leading to an empirical model of accumulation of CBs in biota in the Firth of Clyde. The model was used to predict the accumulation of CBs thereby serving as an indicator for the degree with which these compounds metabolise in mussels. A comparison of the toxicity of benzo[a]pyrene and 2,3,7,8-TCDD was carried out using the H4IIE cell line. This comparison allowed to express the chemical concentrations of individual compounds from the three groups in sediments as toxic equivalents (TEQs) relative to 2,3,7,8-TCDD. The contribution of CBs to the total TEQ was very small (< 1%), followed by the PCDD/Fs contributing up to 5% of the total. PAHs accounted for the largest part of the TEQ (94 to 99%). The biological effect of contaminants in sediments was also determined as P450 enzyme induction produced by sediment extracts in H4IIE cell cultures. The highest toxicity was found in sediments originating from the sewage sludge dump site. When correlating the TEQs from chemical analysis and from cell culture toxicity, the PAHs needed to be included to explain ~ 2/3 of the dioxinlike toxicity. Key words: CB, PCDD, PCDF, PAH, particle size, TOC, sediment, lipid, mussels, Mytilus edulis, plaice, Pleuronectes platessa, planar, benzo[a]pyrene, TEQ, TEF, P450 1A, Firth of Clyde, H4IIE cell culture

Grantor dc:publisher.institution

Robert Gordon University

Year dc:date.issued

1998

Author dc:creator

• Hess, Philipp

Advisor dc:contributor.advisor

• D.E. Wells and M.A.L. Melvin

• Planar aromatic compounds
• Marine environment
• Chlorobiphenyls
• Polychlorinated dioxins
• polycyclic aromatic hydrocarbons
• Firth of Clyde
• Mussels
• Plaice
• Pollution

Language dc:language

en

Identifier

oai:rgu-repository.worktribe.com:2807411
https://doi.org/10.48526/rgu-wt-2807411

OAI identifier oai:identifier

oai:rgu-repository.worktribe.com:2807411