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© 2018 Elsevier Ltd Two Guillemot carcases were dissected, each providing 12 discrete tissue samples and 3 samples of partially digested food. One hundred and five PCBs from the 209 PCBs determined by GCxGC-ToFMS were detected. The relative proportions of individual PCBs did not vary greatly within tissue types, although the PCB profile from undigested food could be distinguished. Enantiomer fractions (EFs) were determined for CB-95, CB-136 and CB-149 by GC-HRqToFMS. EFs in the partially digested food were near racemic, with high levels of enrichment for E1 CB-95 in the kidneys and liver (EF of 0.80 and 0.84 respectively). This provides some of the clearest evidence to date that fractionation takes place in the organs where metabolic biotransformation and elimination of PCBs occurs. Our findings also confirm the ability of non-lethal sampling techniques, such as collection of small ( < 1 g) blood samples, to provide PCB signatures that are representative of an individual organism.

The quality of aircraft cabin air has been an area of concern for several decades. Many investigations have linked the presence of organophosphates in air to Aerotoxic Syndrome with adverse symptoms reported by thousands of aircraft crew across the globe. Currently the source of organophosphates has been under debate, with studies pointing towards tricresylphosphates (TCP) in aircraft oil as the main source due to leaks in engine seals resulting in fumes entering the cabin. However, comparisons of oil and cabin samples have shown that the cabin samples contain a much higher proportion of ortho-substituted TCP than is commonly detected in oil. The aim of this experiment was to investigate the potential for palladium catalysts (present in aircraft air conditioning systems) to convert meta- and para-substituted TCP to produce ortho-substituted TCP through transisomerisation. This experiment was performed in a controlled laboratory setting aimed to represent the conditions likely to be experienced in aircraft. Samples were introduced to a stainless steel micro reactor tube containing the pelletized palladium catalyst using a HPLC pump with a 0.2 ml/min feed flow rate. The temperature maintained at 400 °C over a period of 1 h and samples collected using a condensing vesicle. These were then diluted and transferred to a 2 mL vial for analysis by gas chromatography mass spectrometry. No evidence supporting the transisomerisation of tricresylphosphate was obtained. This indicates that more emphasis should be placed on identifying other potential sources of ortho substituted TCP.

© 2016 Elsevier B.V. An isotope dilution congener-specific method for the determination of the most abundant and most toxic polychlorinated naphthalenes (PCNs) was developed using gas chromatography with high resolution mass spectrometry (GC-HRMS). The method was used to determine the concentration of 24 target congeners and total PCN concentrations in fish and sediment samples. Tissue samples were extracted using pressurized liquid extraction (PLE) and sediment samples were extracted using Soxhlet extraction. Sample extracts were cleaned up using either a manual two-stage open column procedure or an automated FMS Power Prep System with multi-analyte and multi-sample capability using a three-column cleanup procedure. Sediment extracts were cleaned up with a dual open column cleanup technique involving the use of both a multi-layered silica (silver nitrate/acid/base/neutral silica) column followed by column containing carbon-activated silica. Fish tissue extracts were cleaned up on the automated system involving the use of a high capacity ABN (acid/base/neutral column), carbon celite column, and a basic alumina column. The method is capable of producing instrument detection limits (IDLs) between 0.06 and 0.13 pg for each PCN (on column), with method detection limits (MDLs) for the fish extracts ranging from 1.3 to 3.4 pg/g (wet weight) and 0.46 to 1.2 pg/g (dry weight) for sediments. The average accuracy of 34 spiked fish samples analysed over a period of several months was 100% with a precision (%RSD) of 12%. Similarly, the average accuracy for 28 spiked sediment samples was 104% with a precision (%RSD) of 12%. The application of the method to environmental samples was demonstrated through the analysis of sediment and fish samples obtained from Lake Ontario, Canada. The method is used both for the determination of 24 PCNs and to perform non-targeted screening for the remaining 51 PCN congeners, which are included in the total PCN quantification result. It is currently one of the most comprehensive and accurate congener-specific methods available and was developed from the existing techniques used for the determination of polychlorinated dioxins and furans to produce high quality data with only minor modifications in the clean-up procedure. It can therefore be readily adopted by other laboratories performing dioxin and POP analyses.

Polychlorinated biphenyls (PCBs) are one of the most widely studied group of persistent organic pollutants (POPs). There are 209 different PCBs, however not all 209 can currently be individually quantified in one analytical run. This means that a subset of PCBs congeners are often determined and reported. Some of the most commonly reported subsets are the 7 indicator PCBs (28, 52, 101, 118, 138, 153 and 180) and the WHO 12 PCBs (77, 81, 105, 114, 118, 123, 126, 156, 157, 167, 169 and 189). The WHO 12 congeners are co-planar ‘dioxin like’ PCBs that are effective for establishing health risks. The 7 indicator PCBs were selected as some of the most common PCBs across the compositional range of the most common technical mixtures (such as Aroclors), and are used to give an indication of the total PCB concentrations. These groups of indicator PCBs were established several decades ago. However, in the environment commercial mixtures are subject to weathering and fractionation processes, and additional sources of non-Aroclor PCBs are also becoming more important. In this manuscript we use existing large scale comprehensive congener specific datasets to evaluate the effectiveness of indicator PCBs to predict total concentrations and establish if they are still fit for purpose. The results indicate that while these traditional indicators are a useful tool to estimate total concentrations in humans with background exposure there are many instances where they are not fit for purpose and can lead to significant under predictions in total PCB concentrations in environmental matrices.

In this study, polybrominated and mixed halogenated dibenzo-p-dioxins and furans (PBDD/Fs and PXDD/Fs), and dioxin-like polychlorinated biphenyls (dlPCBs) were quantified in 24 human milk samples of first-time lactating mothers from Greater Accra region in Ghana. The aims of the study were to determine the concentrations and toxic equivalent concentrations of PBDD/F, PXDD/F and dlPCBs in human milk, and to estimate an infant's daily intake. The samples were analysed for 12 dioxin-like PCBs, 7 congeners of 2,3,7,8-polybrominated dibenzo-p-dioxins and furans (PBDD/Fs), and 7 congeners of 2,3,7,8-mixed halogenated dioxins and furans (PXDD/Fs, where X = Br/Cl). The mean concentrations in human milk ranged from 0.15 to 212.9 pg/g lipid for dlPCB congeners (mean TEQ: 1.67 pg WHO2005-TEQ/g lipid). Lesser concentrations for 2,3,7,8-PXDD/Fs (and PBDD/Fs congeners) ranged between

4-methylmethcathinone (mephedrone) has emerged in drug seizures as a new psychoactive substance (NPS) causing a public health risk of global concern. Currently, there are no commercial microfluidic devices for the selective detection of mephedrone and so this study presents a simple, low-cost and portable paper-based Lab-on-a-Chip (LOC) device with colorimetric detection to fill this gap. Limits of detection for mephedrone in spiked urine and dissolved powder (aqueous) samples are clinically relevant at 4.34 ng mL−1 and 2.51 ng mL−1 respectively. No cross-reactivity for commonly encountered cutting agents, interferents and adulterants were detected. Mephedrone and its main metabolite were detectable in aqueous and urine samples within 3 min. Stability and reproducibility measurements showed no significant difference in signal intensity over eight weeks and no significant difference within or between devices. The proposed device has the potential to provide cost-effective, rapid, on-site testing within forensic or clinical settings and therefore has wide global applicability.

Human exposure data on dioxins and dioxin-like compounds (DLCs) in Ghana are limited. Based on health risks associated with dioxins and DLCs, the impact of maternal body burdens on foetal exposure is significant. This is the first study that assesses polychlorinated, polybrominated and mixed halogenated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs, PBDD/Fs and PXDD/Fs), and dioxin-like polychlorinated biphenyls (dlPCBs) in sera of primiparous Ghanaians. Our sample selection includes 34 participants from two municipalities (Accra and Tema), and explores contributions from environmental and dietary exposures using questionnaire data. Sample preparation involved C18 solid phase extraction, purification with acidified silica and lipid removal cartridges, and detection with gas chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry. The calculated average toxic equivalent concentration was 5.3 pg TEQ/g lw, with contributions from dlPCBs (1.25 pg TEQ/g lw), PCDD/Fs (3.10 pg TEQ/g lw), PBDD/Fs (0.49 pg TEQ/g lw) and PXDD/Fs (0.50 pg TEQ/g lw). The calculated total TEQ concentration was lower than background TEQ concentrations reported in sera of pregnant women globally. Positive correlations were obtained for total dioxins and DLC concentrations with age and Body Mass Index (BMI). Dietary intake of seafood and dairy products had a strong influence on PCDD/F and dlPCB concentrations. Statistically significant differences were observed for dioxins and DLCs in participants from Accra (in close proximity to Agbogbloshie e-waste site) and Tema. Given the significant TEQ contribution of PBDD/Fs and PXDD/Fs (~20%), it is essential to explore these classes of dioxins and DLCs in future biomonitoring studies as they may pose health risks, and add extra diagnostic information in source exposure investigations.

Ghana is one of the top pesticide users and highest persistent organic pollutant (POP) emitters in sub-saharan Africa. Despite recent increases in published data, there is limited information on how POP concentrations have changed, post ratification of the Stockholm Convention. As a result, this review aims to address these knowledge gaps by collating available data that reported POPs in Ghanaian environmental matrices, identify spatial and temporal trends, and establish potential health risks. It is worth noting that Ghana has not developed its own regulatory standards for POPs, but adapts United States Environmental Protection Agency (USEPA) standards. Results obtained showed concentrations in excess of USEPA regulatory standards for per- and poly-fluoroalkyl sulphonates (PFASs) and dichlorodiphenyldichloroethane (DDD) in water, polychlorinated and polybrominated dibenzo-p-dioxins and furans (PCDD/Fs and PBDD/Fs) in e-waste soils, and polybrominated diphenyl ethers in aquatic organisms and dairy products. The published studies do not cover major regions nationwide. The inconsistency in methods and analytes measured, along with data scarcity in some regions, makes it challenging to identify temporal trends. However, the data did indicate decreasing concentrations of some legacy POPs in soil/sediment and aquatic organisms, with increasing concentrations of some POPs in water, fish, fruits and vegetables. Studies that performed health risks assessments were limited although the data indicated risks to e-waste workers, some farmers and vulnerable sub-populations. This review identified potential human health risks from POPs in the Ghanaian environment and the need for more consistent and widespread monitoring program.

Where rare species are concerned, including those with restricted range, their use for traditional medicine can have disastrous impacts on local populations already under pressure. Difficulty in monitoring such illegal activity has been illustrated by enforcement raids across India since June 2017, with authorities seizing supposedly rare Himalayan plant roots referred to as hatha jodi.

PCB signatures can be used for source identification, exposure studies, age dating and bio-monitoring. This study uses comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GCxGC-ToFMS) to produce a PCB signature comprised of over 80 PCBs for individual Leach's storm petrels (Oceanodroma leucorhoa). The Leach's storm petrel is a relatively small, elusive, understudied pelagic bird, which only returns to remote islands under darkness during the breeding season. Samples were obtained from 25 Leach's storm petrels found dead in Canada and the UK following storm events in 2006 and 2009. Tissue samples were extracted and analysed by GCxGC-ToFMS and results showed that 83 PCB congeners were present in >60% of samples. An assessment of the PCB signature in four different tissue types showed that it did not vary greatly in samples obtained from the gut, heart, liver and stomach. Multivariate statistical analysis identified a distinctive PCB signature in birds from Canada and Europe which was used to identify the regional provenance and transatlantic movement of individual birds. The findings showcase the ability of GCxGC-ToFMS to provide the high quality congener specific analysis that is necessary for PCB fingerprinting, as well as highlighting the potential of PCB signatures for use in ecological studies of movement, foraging and behaviour.

We provide an initial insight into the occurrence and characteristics of animal-visitor interactions (AVIs) involving captive wild animals within zoos and aquaria. Using information provided online via official public websites of modern zoos and aquaria, we found that AVIs were provided by the majority of facilities. Our study revealed that a variety of AVI types were being offered. Globally, petting captive wild animals was the most prevalent AVI type advertised (n = 1241 observations, 43% (534) of facilities) and Mammalia was the most advertised taxonomic class (n = 5142, 53% (2739)). We found certain AVI types that were more commonly offered than predicted. These were opportunities to: (1) Hand feed captive wild animals in Asia, North America and Oceania, (2) ride wild animals in Europe and North America, (3) walk with or swim through wild animal enclosures in Asia, and (4) walk with wild animals in Asia and Europe. Given the global prevalence of AVIs in modern zoos and aquaria, and an apparent lack of animal welfare focused research, we provide recommendations to help effectively balance and manage captive wild animal welfare with other primary interconnected goals.

A method to determine halogenated flame retardants was developed that utilizes gas chromatography with atmospheric chemical ionization (APCI) high-resolution quadrupole time-of-flight mass spectrometry (HRqTOFMS). The new GC-APCI-HRqTOFMS method was used to determine the presence of 65 halogenated flame retardants (HFRs) in the United Sates National Institute of Standards and Technology (NIST) organic contaminants in house dust standard reference material (SRM). The accuracy of the measurements was compared to the certified NIST value for polybrominated diphenyl ethers (PBDEs) and had an average accuracy for the 14 certified PBDEs of 109% with subpicogram detection limits (on column) from a single 1 μL injection with a run time of 18 min. SRM2585 extracts were also analyzed by GC electron ionization (EI) high-resolution mass spectrometry (HRMS), and there was an excellent correlation between the two data sets (R2 value of 0.996). The presence of 25 additional HFRs were also screened in the dust standard, and 10 were detected in concentrations above the limits of detection; these were p-TBX, PBBZ, PBT, PBEB, TDCPP, HBBZ, EHTBB, TBBPA, BEHTBP, and BTBPE. The results presented show that the proposed APCI-HRqTOFMS method was comparable and in many cases an improvement on the existing EI-HRMS method.

The field of environmental forensics emerged in the 1980s as a consequence of legislative frameworks enacted to enable parties, either states or individuals, to seek compensation with regard to contamination or injury due to damage to the environment. This legal environment requires stringent record keeping and defendable data therefore analysis can sometimes be confined to data to be obtained from certified laboratories using a standard accredited analytical method. Many of these methods were developed to target specific compounds for risk assessment purposes and not for environmental forensics applications such as source identification or age dating which often require larger data sets. The determination of persistent organic pollutants (POPs) for environmental forensic applications requires methods that are selective but also cover a wide range of target analytes which can be identified and quantified without bias. POPs are used in a wide variety of applications such as flame retardants, fire suppressants, heat transfer agents, surfactants and pesticides mainly because of their chemical inertness and stability. They also include compounds such as dioxins that can be unintentionally produced from industrial activities. POPs are persistent in the environment, bioaccumulative and/or toxic and therefore require analytical methods that are sensitive enough to meet the low detection limits needed for the protection of the environment and human health. A variety of techniques, procedures and instruments can be used which are well suited for different scenarios. Optimised methods are important to ensure that analytes are quantitatively extracted, matrix coextractables and interferences are removed and instruments are used most effectively and efficiently. This can require deviation from standard methods which can open the data up to further scrutiny in the courtroom. However, when argued effectively and strict QA/QC procedures are followed the development and optimization of methods based on investigation specific scenarios has the potential to generate better quality and more useful data.

Fresh and used aircraft engine lubricants (Mobil Jet Oil II) were analysed using a Fourier Transform Ion Cyclotron Resonance Mass Spectrometer (FTICRMS) and comprehensive two dimensional gas chromatography with high resolution time of flight mass spectrometry (GCxGC-HRTOFMS). The composition of the fresh oil was established, with special focus to its tricresyl phosphate (TCP) content as this has formed the focus for most investigations into aerotoxic syndrome. The results showed that only four TCP isomers were present at detectable levels in the fresh oil: mmm-TCP, mmp-TCP, ppm-TCP and ppp-TCP. The results indicate that the formulation of Mobile Jet Oil II does not contain the more toxic ortho substituted TCP isomers at concentrations above 0.0005%. The temperatures of jet engines during operation are greater than 200 °C which creates the potential to alter the composition of the original oil and create other toxic compounds. The results show there may be a significant risk from alkylated cresyl phosphates, which were identified in the used oils at concentrations calculated in the range of 0.13–0.69%. w/w. Several xylenyl and ethylphenyl phosphates have been shown to exhibit a similar toxicity to ortho substituted TCP isomers which makes there discovery in used oil significant. These compounds should be included in future aircraft air quality studies and when assessing the risks and causes of aerotoxic syndrome.

A comprehensive method to extract perfluoroalkane sulfonic acids (PFSAs), perfluoroalkyl carboxylic acids (PFCAs), polyfluoroalkyl phosphoric acid diesters (diPAPs), perfluoroalkyl phosphinic acids (PFPiAs) and perfluoroalkyl phosphonic acids (PFPAs) from sediment and analysis by liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed and applied to sediment cores from three small isolated lakes (Plastic Lake, Lake 442, Lake Tettegouche) and Lake Ontario in the Great Lakes Region. Recoveries of the target compounds using the optimized acetonitrile/sodium hydroxide extraction ranged from 73% to 120%. The greatest concentrations of per- and polyfluorinated alkyl substances (PFASs) were recorded in sediment from Lake Ontario (ΣPFASs 13.1 ng/g), where perfluorooctane sulfonic acid (PFOS) contributed over 80% of the total. Concentrations in Lake Ontario were approximately 1-2 orders of magnitude greater than the more remote lakes subject to primarily atmospheric inputs. Whilst the PFAS contribution in Lake Ontario was dominated by PFOS, the more remote lakes contained sediment with higher proportions of PFCAs. Trace amounts of emerging PFASs (diPAPs and PFPiAs) were found in very recent surface Lake Ontario and remote lake sediments.

Detailed polychlorinated biphenyl (PCB) signatures and chiral Enantiomer Fractions (EFs) of CB-95, CB-136 and CB-149 were measured for 30 workers at a transformer dismantling plant. This was undertaken to identify sources of exposure and investigate changes to the PCB signature and EFs over different exposure periods. Approximately 1.5 g of serum was extracted and PCB signatures were created through analysis by comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC × GC–TOFMS) and EFs calculated following analysis by gas chromatography with high resolution mass spectrometry (GC–HRMS). A total of 84 PCBs were identified in the serum samples with concentrations of the 7 indicator PCBs ranging from 11–350 ng g−1 of serum (1.2–39 μg g−1 lipid). The PCB signatures were interpreted using principal component analysis (PCA) which was able to distinguish workers with background or recent minimal exposure from those with prolonged occupational exposure. Occupationally exposed individuals had a similar PCB profile to Aroclor A1260. However, individuals with prolonged exposure had depleted proportions of several PCB congeners that are susceptible to metabolism (CB-95, CB-101 and CB-151) and elevated proportions of PCBs that are resistant to metabolism (CB-74, CB-153, CB-138 and CB-180). The results also identified a third group of workers with elevated proportions of CB-28, CB-60, CB-66, CB-74, CB-105 and CB-118 who appeared to have been exposed to an additional source of PCBs. The results show near complete removal of the CB-95 E2 enantiomer in some samples, indicating that bioselective metabolism or preferential excretion of one enantiomer occurs in humans. By considering PCB concentrations along with detailed congener specific signatures it was possible to identify different exposure sources, and gain an insight into both the magnitude and duration of exposure. Keywords: Polychlorinated biphenyls (PCBs), Human exposure, GC × GC–TOFMS, Chemical fingerprinting, PCB atropisomers, Chiral, Enantiomer fractions

Polychlorinated biphenyls (PCBs), dioxins (PCDDs) and furans (PCDFs) are frequently detected in grass, soil and farm animals near incineration plants, electric transformers recycling facilities, or after major fires during environmental forensic investigations. The sale of farm animals for food above established PCBs and PCDD/F limits is forbidden, and therefore are slaughtered, or removed from contaminated areas to graze on uncontaminated food, in an attempt to detoxify. If regulated levels are exceeded in one sample, the impacts are rarely limited to one area, or within the sampling period. It is therefore important to establish the extent of the contamination, distinguish the potential source(s) and identify the duration of the contamination event. This manuscript examine potential pitfalls in the analysis of (PCBs), dioxins (PCDDs) and furans (PCDFs) in terms of their regulated levels, sampling challenges, the analysis of samples and statistical interpretation of the test data.

Interaction between the regulator and practitioners in the field of environmental investigations An introduction to a multiparameter approach to improve the reliability of environmental crime evidence Environmental litigation issues in Taiwan and the forensics strategies of chlorinated hydrocarbon contaminated sites Forensic investigations in a PCB case: potential pitfalls and tips Use of symmetric tetrachloroethane to age date chlorinated solvent releases A forensic methodology for investigating chlorinated solvent releases from a dry cleaner 13C and delta37Cl on gas-phase TCE for source identification investigation - Innovative solvent-based sampling method Characterisation and modeling of dust in a semi-arid construction environment Assessment of polycyclic aromatic hydrocarbons in an urban soil dataset Statistics of lost historical coal tar PAH contamination in soils and sediments Micro-bubbles oxygen injection in groundwater contaminated by organic biodegradable compounds and metals Heavy metals (lead, cadmium, chromium, nickel and zinc) contamination in selected electronic waste dumpsites in Lagos, Nigeria Evidence for acid mine drainage in an urban stream in the West Midands A Practical Evaluation of Petrogenic and Biogenic Methane Sources in the Context of Redevelopment and Explosive Hazard Management in Los Angeles, California Subject Index

PCBs were first produced in 1929 and were widely used throughout the 20th century for a variety of industrial uses such as dielectric fluids, hydraulic fluids and plasticisers. Production rates decreased steadily throughout the 1970's as the health and environmental risks from PCBs began to be better understood. In the United States this resulted in passing of the Toxic Substances Control Act in 1976, with PCBs phased out from 1979. However, PCBs can still be found in closed systems such as dielectric fluids in electrical equipment. They are highly persistent and still routinely found in environmental and human samples across the globe. All humans have been exposed to background concentrations of PCBs, however, there are also events where individuals are exposed to elevated concentrations. In litigation cases it is important to differentiate specific exposure events from background exposure, as well as identifying the source of contamination and age dating the exposure period. Age dating PCB exposure is complex, but assessments can be made because different PCB congeners have different residence times in the human body.

Environmental forensics is a growing multidisciplinary field which combines traditional applied sciences, in particular analytical chemistry, with socioeconomic factors to identify the source, age, and timing of a contaminant into the environment. Persistent organic pollutants (POPs) are a group of priority pollutants which by their chemical nature are capable of long-range transport and biomagnification in food chains, including bioaccumulation in human and animal tissue. Mounting scientific evidence has suggested that they may be found not only in industrial locations but also in remote regions, such as deep ocean sediments and the Antarctic. They have been found to pose a significant risk to the environment and human health prompting the formation of environmental bodies like the United States Environmental Protection Agency and lead to the implementation of regulations to restrict their use. This chapter highlights significant discoveries of POPs in the environment, development of key analytical techniques and legislative milestones in the control of POPs in the environment. It also includes a brief description of the physical and chemical properties of POPs and finishes with a concise explanation of the main environmental processes that control the environmental behavior of POPs.

Worldwide there is concern about the continuing release of persistent organic pollutants (POPs) into the environment. To complete an environmental forensic investigation of POPs in the terrestrial environment, an understanding of the source, fate, and behavior of POPs in terrestrial media is required. This chapter examines a variety of terrestrial environments, including soil and sediments, herbage, wildlife, and humans. It includes discussion on the major pathways in which POPs enter each media, the changes which may occur within the media, background concentrations and patterns which may be used to interpret the potential sources of POPs in each media. Two case studies are presented at the end of this chapter to provide context to the discussion and highlight how environmental forensics investigations in the terrestrial environment may be carried out using different tools.

A GC × GC-TOFMS installed with a Rtx-PCB (60 m × 0.18 mm × 0.18 μm) in the first dimension and Rxi- 17 (1.5 m × 0.1 mm × 0.1 μm) column in the second dimension was used to separate 188 out of 209 congeners. A further 12 congeners were identified through additional data processing resulting in the identification of a total of 200 congeners. However, caution is advised if these 12 congeners were to be used in quantitative assessments. The remaining 9 co-eluting congeners were three doublets (CB65 + CB62, CB160 + CB163 and CB201 + CB204) and one triplet (CB20 + CB21 + CB33). This method was tested on five Aroclors and resulted in the separation of all congeners present in the heavier Aroclor mixtures A1254 and A1260. The suitability of this method for applications in biological matrices was demonstrated on extracted whiting and guillemot liver samples which resulted in the identification of 137 individual PCBs in the whiting liver sample and 120 in the guillemot sample. Fingerprinting was able to show clear differences in the PCB signature of the two animals. This highlights the potential of this method for PCB fingerprinting in environmental forensics studies and other assessments that require congener specific analysis.

In human exposure studies involving Polychlorinated Biphenyls (PCBs), it is useful to establish when an individual was potentially exposed. Age dating PCB exposure is complex but assessments can be made because different PCB congeners have different residence times in the human body. The less chlorinated congeners generally tend to have shorter residence times because they are biotransformed and eliminated faster than more chlorinated congeners. Therefore, the presence of high proportions of less chlorinated congeners is often indicative of recent exposure. The 2003-04 National Health and Nutrition Examination Survey (NHANES) dataset contains results for the concentration of 37 PCBs in a sub-sample of the US population. Multivariate statistical analysis of the NHANES data showed that less chlorinated congeners are not always biotransformed faster than higher chlorinated compounds. For example, PCB 28 (a tri-chlorobiphenyl) appears to be more resistant to biotransformation than PCB 101 and 110 (penta-chlorobiphenyls). Using statistical analysis of the NHANES data in conjunction with previously published studies on PCB persistence in humans, it was possible to identify the structural relationships that determine if a PCB is likely to be from a recent exposure (termed 'episodic') or from steady state exposure. Congeners with chlorine atoms in the 2,5- and 2,3,6-positions appear to be more susceptible to biotransformation whereas congeners with chlorine bonds in the 2,3,4- 2,4,5- 3,4,5- and 2,3,4,5-positions appear to be more persistent. This work shows that future investigations to date PCB exposure would benefit from the analysis of a wide range of congeners, including the selection of key congeners based not only on the degree of chlorination but also on the positions of the chlorine atoms on the biphenyl.

Nutrient concentrations within watercourses are often associated with the input of sewage or the runoff of fertilizers. Due to population increases, there has been a dramatic rise in the amount of fertilizer applied to land, as well as in the further development of sewage treatment plants (STPs), both of which can lead to significant discharges with associated eutrophication risks in coastal waters. The implementation of the European Union Water Framework Directive (EU-WFD) should improve the management and quality of European water bodies. The Ria Formosa Lagoon, Portugal, is one such water body monitored under the WFD where two inter-calibration sites have been developed, that of the Anc˜ao Basin, which has a status of “high/good,” and that of the Ramalhete Channel, with a status of “good/moderate.” Spatial nutrient concentrations (NH+ 4 , NO–2 , NO–3 , PO3–4 ) and lipids were measured in two areas that were thought to contribute nutrients into the Anc˜ao Basin; a river that flows through several golf courses and the Ramalhete Channel, which receives discharge from both Faro Airport and a STP. Nutrient analyses showed that waters from the Ramalhete Channel had substantial concentrations, the highest of which was ammonium, which exceeded 180 μM near the sewage discharge site; however, concentrations diminished towards the sea, reaching 2.7 μM suggesting the utilization of NH+4 by seagrasses (Zostera noltii).The Atlantic Ocean was also a source of nitrate, contributing 1.8 μM, whereas sources of phosphate originated in the Anc˜ao Basin catchment and included a commercial horticulture site,several golf courses, and the STP. Principal component analysis (PCA) and cross plots of the 5β-coprostanol/cholesterol and 5β-coprostanol/(5β-coprostanol + 5α-cholestanol) ratios identified areas of fecal contamination, highlighting several sites previously unknown to contain sewage matter. In general, nitrogen sources were associated with agriculture and phosphate originated from the golf complex and sewage discharges. These effects were partly mitigated, however, by eutrophic ponds between the river and the lagoon.

Many allotments in the UK today are situated on urban brownfield areas which creates a potential human health risk from soil borne contamination. This paper looks specifically at the risks to allotment users at a site in Rochdale, UK, from polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-furans (PCDD and PCDF). A contaminated land investigation was undertaken involving the collection and analysis of 24 soil samples from the top 0.0-0.3 m of the soil profile. Homogenised egg samples were also collected and analysed from plots where poultry were kept. The concentration of PCDD and PCDF in soil at the site varied from 0.69 to 13.62 μg kg(-1); two plots out of a total of eight exceeded the soil guideline value (SGV) of 8 μg kg(-1), however all plots fell below the site specific assessment criteria (SSAC) of 15.9 μg kg(-1). Human health risks were assessed using the Environment Agency's contaminated land exposure assessment (CLEA) model. The assessment using CLEA alone did not provide enough evidence to indicate significant possibility of significant harm (SPOSH) across the entire allotment site. However, when the likely exposure from the soil was combined with potential exposure from consumption of site laid eggs, the results indicated that the potential risks could constitute SPOSH. This paper gives evidence to support the bioconcentration of PCDD and PCDF in eggs and highlights the importance of considering pollutant linkages outside the generic CLEA model.

The South West Nuclear Hub has joined with its industrial partners to engage with the public about the pros and cons of nuclear power, and open a balanced and evidence-based dialogue around common areas of concern, such as nuclear safety and nuclear waste. This programme of industrial engagement must continue into the future if we are to understand and effectively address those concerns, and make the UK’s nuclear renaissance work for all.