Publications by authors named "Lynda Webster"

Human activities have introduced significant amounts of anthropogenic chemicals into marine ecosystems, posing threats to aquatic biodiversity and human health. Although, traditional marine monitoring focus primarily on legacy pollutants, the presence and potential risks associated with complex emerging chemical mixtures should not be neglected. In the context of the present study organized via OSPAR Commission and supported by NORMAN network, 52 marine samples were gathered from North-East Atlantic Ocean.

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Contracting Parties to the OSPAR Convention for the Protection of the Maine Environment of the North-East Atlantic are required to undertake monitoring and assessment of both inorganic and organic contaminants. There is a requirement to assess contaminants across different trophic levels on an ecosystem-specific basis. However, this is currently constrained by the availability of relevant samples to cover the full range of trophic levels.

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To be able to assess progress towards "Good Environmental Status" adopted across European Member States, and by the United Kingdom through its 3-stage Marine Strategy, contaminant concentrations and their biological effects need to be assessed in environmental samples by comparison to assessment criteria. This study examines the variability of concentrations (inter- and intra- species variation) of three priority heavy metals (Hg, Cd and Pb) and six additional trace metals and metalloids (As, Ni, Se, Zn, Cu and Cr) in twenty-three species across four trophic levels from different locations around Scotland. Trophic magnification factors (TMFs) were calculated using two methods for metals/metalloids possessing a significant trophic relationship (Hg, Cd, Cu, Ni and Zn) to refine and improve the application of TMFs to assess and predict biomagnification risk of metals/metalloids to biota in the environment.

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This is the first regional, multi-annual assessment of floating microplastics in Scotland's seas. Sea surface samples were collected from 2014 to 2020, using a catamaran swimmer body/neuston net trawl and evaluated for the presence of microplastics. Microplastics were present in the surface waters of all Scottish Marine Regions (SMR) and Offshore Marine Regions (OMR) though almost 35% of sample sites contained no microplastics.

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Understanding the status of contaminants in the marine environment is a requirement of European Union Directives and the Regional Seas Conventions, so that measures to reduce pollution can be identified and their efficacy assessed. The international ICON workshop (Hylland et al., in this issue) was developed in order to test an integrated approach to assessing both contaminant concentrations and their effects.

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The bioaccumulation of persistent organic pollutants (POPs) in deep sea fish from the Rockall fishing area was investigated. Predator and prey species were analysed for stable isotopes, fatty acids, polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). δ(15)N indicated that black scabbard was at the highest trophic level and the prey the lowest.

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Concentrations and patterns of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in the blubber of the five most common toothed whales off the Northwest Iberian Peninsula (NWIP), specifically common dolphin, long-finned pilot whale, harbour porpoise, striped dolphin and bottlenose dolphin, were investigated. The study revealed that differences in PCB and PBDE concentrations among the species are highly dependent on age and sex but also on ecological factors such as trophic level, prey type and habitat. Of the five species studied, bottlenose dolphin and harbour porpoise showed the greatest concentrations of PCBs.

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Concentrations of Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, V and Zn were investigated in the liver and kidney of the five most common toothed whales off the Northwest Iberian Peninsula (NWIP), specifically common dolphin, long-finned pilot whale, harbour porpoise, striped dolphin and bottlenose dolphin. Differences were observed in the bioaccumulation of the above elements between the five species. The differences are probably related to biological factors such as age and sex and/or to ecological factors specific to each species such as feeding habits or bioavailability of the various elements.

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Molecular responses to acute toxicant exposure can be effective biomarkers, however responses to chronic exposure are less well characterised. The aim of this study was to determine chronic molecular responses to environmental mixtures in a controlled laboratory setting, free from the additional variability encountered with environmental sampling of wild organisms. Flounder fish were exposed in mesocosms for seven months to a contaminated estuarine sediment made by mixing material from the Forth (high organics) and Tyne (high metals and tributyltin) estuaries (FT) or a reference sediment from the Ythan estuary (Y).

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A wide variety of organic contaminants including pesticides, polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) have previously been detected in surface waters in the river Ythan catchment, North East Scotland UK. While the concentrations detected were below Water Framework Directive Environmental Quality Standards (WFD-EQSs) environmental exposures to the diverse mixtures of contaminants, known and unknown, may pose chronic and/or sublethal effects to non target organisms. The present study assessed the embryo and algal toxicity potential of freely dissolved organic contaminants from the Ythan catchment using silicone rubber passive sampling devices (SR-PSDs) and miniaturised bioassay techniques.

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The use of a silicone rubber passive sampler for the assessment of the availability of lipophilic organic contaminants in sediments is described. The passive sampler accumulated polycyclic aromatic hydrocarbons (PAHs) from sediments with an equilibration time of 20 days for most PAHs. The method was used to measure the free dissolved concentrations in pore water of 30 PAHs (parent and alkylated), their water exchangeable concentrations and sediment-water partition coefficients in field sediments from a Scottish sea loch that supports fish farming.

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As an alternative procedure to conventional water quality assessment, the presence and combined toxicity of dissolved organic contaminants in water at five sites in the Forth estuary and the Firth of Forth, Scotland, United Kingdom was investigated using silicone rubber passive sampling devices (SR-PSDs) and an algal growth inhibition bioassay. SR-PSDs were deployed in water at the five sites for ~2 months. Following retrieval, extracts from the deployed SR-PSDs were assessed for both algal growth inhibition and the occurrence of a wide range of organic contaminants, including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and a variety of plant protection products (PPPs; commonly referred to collectively as 'pesticides').

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This study evaluates the potential of silicone rubber passive sampling devices (SR-PSDs) as a suitable alternative to automatic water samplers (autosamplers) for the preliminary identification of a wide range of organic contaminants in freshwater systems. The field performance of SR-PSDs deployed at three sites on two streams of an agricultural catchment area in North East (NE) Scotland, United Kingdom (UK) was assessed concurrently with composite water samples collected from two of the sites using autosamplers. The analytical suite consisted of selected plant protection products (PPPs; commonly referred to collectively as 'pesticides'), including 47 pesticides and a separate sub-category of 22 acid/urea herbicides.

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We investigated the feasibility of coupling passive sampling and in vitro bioassay techniques for both chemical and ecotoxicological assessment of complex mixtures of organic contaminants in water. Silicone rubber passive sampling devices (SR-PSDs) were deployed for 8-9 weeks in four streams and an estuary of an agricultural catchment in North East (NE) Scotland. Extracts from the SR-PSDs were analysed for freely dissolved hydrophobic organic contaminants (HOCs) and screened for wide range of pesticides.

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Short chain chlorinated paraffins (SCCPs) are a group of persistent organic pollutants (POPs) of increasing concern, but are to date not widely investigated in the environment, largely due to the challenges involved in their quantification. Here, SCCPs were quantified in marine sediments from the Firth of Clyde, Scotland, by gas chromatography with electron capture negative ionisation mass spectrometry (GC-ECNIMS) and through carbon skeleton analysis by gas chromatography with flame ionisation detection (GC-FID), and the analytical challenges encountered are discussed. Concentrations in the sediments ranged from 0.

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The availability of polycyclic aromatic hydrocarbons (PAHs) from marine sediments to the ragworm (Nereis virens) was studied. Concentrations of PAHs in pore waters were determined using silicone rubber passive samplers. Calculated bioconcentration factors confirmed that partitioning of PAHs between the lipid phase of the polychaetes and pore water is a passive process.

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Concentrations of persistent organic pollutants (POPs), including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were determined in sediment and biota (fish liver) from around Scotland. The concentrations were investigated using assessment criteria developed by OSPAR and ICES. Organic contaminant concentrations, PAHs, PCBs and PBDEs in sediment, and PCBs and PBDEs in fish liver, were significantly higher in the Clyde compared to all other sea areas.

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Halogenated persistent organic pollutants [polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs)] along with total lipid, were measured in the liver and muscle of three species of deep water fish (black scabbard, black dogfish (liver only) and roundnose grenadier) collected from the Rockall fishing area, to the west of Scotland, between 2006 and 2008. Both contaminant groups were detected in the muscle and liver, with concentrations of PCBs being higher than PBDEs. There were no significant differences in the PCB or PBDE concentrations between the three species, or different sampling locations in the Rockall fishing area.

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Efficient oil spill management in the marine environment requires the ability to predict the rate of loss of individual priority hydrocarbon compounds from marine organisms. Rate of elimination of polycyclic aromatic hydrocarbons (PAHs) from mussels decreases with increase in molecular weight and degree of alkylation.

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Halogenated persistent organic pollutants (chlorobiphenyls (CBs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD) and tetrabromobisphenol-A (TBBP-A)) and total lipid content were measured in the liver and muscle of three species of deep water fish (black scabbard, roundnose grenadier and black dogfish) collected from the Rockall Trough, to the west of Scotland, in 2006. CB concentrations (SigmaICES (International Council for the Exploration of the Seas)7 CBs) >500 microg kg(-1) lipid weight) were found in 9 of the 31 deep water fish liver samples. Non-ortho CBs were measured in samples with the highest ortho CB concentrations.

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Silicone rubber sheeting can be used as a passive sampling device for hydrophobic organic contaminants in the environment to determine the available concentrations in water and sediments. Reliable sampler-water partition coefficients are required to determine the sampling rates and the dissolved contaminant concentrations in water and in sediment pore water. Log partition coefficients (logK(sr,w)) for silicone rubber-water have been estimated for 32 polycyclic aromatic hydrocarbons (PAHs), 2 deuterated PAH analogues and 32 chlorobiphenyls (CBs) using the cosolvent method, with methanol as cosolvent.

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A composite random sampling design was used to estimate the concentrations of hydrocarbons in sediments from two near-shore areas of Scotland (Firth of Clyde and Firth of Forth). The aim of this work was to estimate a mean value for each parameter in these areas, and to determine whether this can be done with more thorough coverage (better representation), better precision and less variance at lower analytical cost through a composite random sampling scheme rather than a simple random sampling scheme, and thereby contribute to the re-design of the UK National Marine Monitoring Programme (NMMP), re-named the UK Clean Seas Environmental Monitoring Programme (CSEMP) in 2006. Samples were collected using a simple random sampling design during 2005.

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Concentrations of organic contaminants were determined in sediment and fish collected annually at six sites around Scotland between 1999 and 2005, as part of the UK National Marine Monitoring Programme. Polycyclic aromatic hydrocarbons (PAHs) and chlorobiphenyls (CBs) were measured in sediment, while CBs and ethoxyresorufin-O-deethylase (EROD) activities were measured in the fish. Highest PAH concentrations in sediment were found at sites where higher coastal influences would be expected (e.

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A method was developed for the determination of the major storage lipids, wax ester and triglycerides, in the copepod Calanus finmarchicus. A variation of the Folch method was used to extract the lipid. The method was scaled down to enable the extraction of either pooled (-1 mg) or individual (approximately 200 microg) copepods.

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The distribution and composition of hydrocarbons in sediment from the Fladen Ground oilfield in the northern North Sea have been investigated. The total PAH concentrations (2- to 6-ring parent and alkylated PAHs, including the 16 US EPA PAHs) in sediments were relatively low (<100 microg kg(-1) dry weight). The PAH, the Forties crude and diesel oil equivalent concentrations were generally higher in sediment of fine grain size and higher organic carbon concentration.

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