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The natural product ambergris is only found rarely on beaches, as jetsam. Even more scarce, or even absent, are accounts of flotsam ambergris. Here, we report the chemical analysis of a rare, large piece (>100kg) of flotsam found in the Atlantic in 2019. About 95% of subsamples from the outside of the coprolith was soluble in dichloromethane. Of this, FTIR spectroscopy, APCI-MS and GC-MS indicated the presence of ambrein. Radiocarbon dating indicated that the sample was post 1950s in age. The 13 C/ 12 C isotope ratio (-22.5 ‰) was typical of those reported to date for whale 'body' ambergris. Metals of ambergris have hardly been reported previously. The distribution found here for the flotsam, was dominated by copper and zinc, which is similar to that of several squid species. This is also consistent with the presence of squid beaks in the coprolith. Squid are a major prey species of sperm whales.

Studying cellular mechanoresponses during cancer metastasis is limited by sample variation or complex protocols that current techniques require. Metastasis is governed by mechanotransduction, whereby cells translate external stimuli, such as circulatory fluid shear stress (FSS), into biochemical cues. We present high-throughput, semi-automated methods to expose cells to FSS using the VIAFLO96 multichannel pipetting device custom-fitted with 22 G needles, increasing the maximum FSS 94-fold from the unmodified tips. Specifically, we develop protocols to semi-automatically stain live samples and to fix, permeabilize, and intracellularly process cells for flow cytometry analysis. Our first model system confirmed that the pro-apoptotic effects of TRAIL therapeutics in prostate cancer cells can be enhanced via FSS-induced Piezo1 activation. Our second system implements this multiplex methodology to show that FSS exposure (290 dyn cm -2 ) increases activation of murine bone marrow-derived dendritic cells. These methodologies greatly improve the mechanobiology workflow, offering a high-throughput, multiplex approach., (© 2024. The Author(s).)

Most of the polycyclic aromatic hydrocarbons (PAHs) in petroleum are alkylated (alkyl PAHs), still the metabolism of these alkyl PAHs to the expected acid products (polycyclic aromatic acids; PAAs) has yet to be demonstrated in oil-exposed fish. Should these compounds be discovered in fish as they have in ragworm, rodents, and humans, they could present an indicative biomarker for assessing oil pollution. In this study, the ability to biotransform alkyl PAHs to PAAs was examined on Atlantic haddock (Melanogrammus aeglefinus). Exposure to phenanthrene, 1-methyphenanthrene or 1,4-dimethylphenanthrene was performed via intraperitoneal injection. An Ion Mobility Quadrupole Time-Of-Flight Mass Spectrometer (IMS-Q-TOF MS) was used in exploratory analysis of extracted bile samples. Acquisition of four-dimensional information by coupling liquid chromatography with the IMS-Q-TOF MS and in-silico prediction for feature prioritization in the data processing workflow allowed several tentative identifications with high degree of confidence. This work presents the first detection of PAAs in fish and suggests the importance of investigating alkyl PAHs in ecotoxicological studies of oil-polluted fish environments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

The use of atmospheric pressure chemical ionisation (APCI) compact mass spectrometry (CMS) was investigated for the analysis of jetsam and museum-archived ambergris and of ambergris components in perfumes. The data were compared with those from existing methods. Authentic samples of some individual ambergris constituents (ambrein, coprostanol, epicoprostanol and coprostanone), were also examined. Rapid APCI CMS was achieved using either a solids probe or a probe with solutions held in capillary melting point tubes. Interpretation is made of the spectra of the principal natural product components, the relative ion responses were measured and the elemental composition of key ions in the spectra confirmed using high resolution accurate mass APCI MS. Rapid analysis of ambergris by APCI CMS may prove to be a further convenient method of identifying ambrein, of measuring the relative ratios of ambrein and steroids in ambergris and even of quantifying the latter, with minimal sample preparation.

A tumor nano-lysate "TNL" vaccine comprised of sonicated 4T1 cells was developed, characterized and implemented for the prevention of triple-negative breast cancer. This study aimed to gain a better understanding of the immune response behind the success of the vaccine in vivo, through use of ex vivo and in vivo assays. Here, we analyze the activation of various immune cells isolated from healthy mouse spleens and find that antigen-presenting cells (APCs) such as dendritic cells (DCs) are being activated following 24 h incubation with 1:10 mg TNL/mg splenocytes. These cells were further explored to determine the pathway by which activation is occurring, and it was observed that TNL are phagocytosed by DCs to activate NF-kB and c-Fos pathways, resulting in enhanced cytokine release after 24 h. An in vivo temporal analysis was performed in mice to understand the immune response at 1, 3, 7 and 10 days after one 100 μL dose of TNL consisting of 10 5 sonicated 4T1 cells via cardiac puncture and splenocyte and peripheral blood mononuclear cell (PBMC) analysis. Changes were observed for up to one week. A multiple dose study was performed comparing mice that were vaccinated with one dose of TNL administered every ten days for 3 doses total, as well as a PBS vehicle control. Survival for TNL-vaccinated mice was enhanced compared to the PBS control, and there was an average delay of 10 days in the onset of metastasis. The differences between the groups at the end of the study demonstrate the potential for TNL as a preventative therapeutic., Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest to declare., (Copyright © 2023. Published by Elsevier B.V.)

Identifying the sources of environmental oil contamination can be challenging, especially for oil in motile organisms such as fish. Lipophilic hydrocarbons from oil can bioaccumulate in fish adipose tissue and potentially provide a forensic "fingerprint" of the original oil. Herein, diamondoid hydrocarbon distributions were employed to provide such fingerprints. Indices produced from diamondoids were used to compare extracts from fish adipose tissues and the crude and fuel oils to which the fish were exposed under laboratory conditions. A suite of 20 diamondoids was found to have bioaccumulated in the dietary-exposed fish. Cross-plots of indices between fish and exposure oils were close to the ideal 1:1 relationship. Comparisons with diamondoid distributions of non-exposure oils produced overall, but not exclusively, weaker correlations. Linear Discriminatory Analysis on a combined set of 15 diamondoid and bicyclane molecular ratios was able to identify the exposure oils, so a use of both compound classes is preferable., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Ex vivo activation of dendritic cells (DCs) has been widely explored for targeted therapies, although these treatments remain expensive. Reducing treatment costs while enhancing cell activation could help to make immunotherapies more accessible. Cells can be activated by both internal and external forces including fluid shear stress (FSS). FSS activates cells via opening of mechanosensitive ion channels. In this study, dendritic cells were activated by sustained exposure to circulatory levels of fluid shear stress using a cone-and-plate flow device and analyzed for activation markers. After 1 h of shear stress exposure, an increase in cytokine release was present in immortalized cells as well as phosphorylation of the proteins NF-κB and cFos in primary DCs. Changes in DC morphology, metabolism and proliferation were also observed. These compelling new findings point to the potential for using FSS to activate DCs for ex vivo therapeutics., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: The authors have submitted a U.S. patent application on the activation of immune cells with fluid shear stress, for various cancer therapy applications., (Copyright © 2023 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Atlantic haddock (Melanogrammus aeglefinus) embryos bind dispersed crude oil droplets to the eggshell and are consequently highly susceptible to toxicity from spilled oil. We established thresholds for developmental toxicity and identified any potential long-term or latent adverse effects that could impair the growth and survival of individuals. Embryos were exposed to oil for eight days (10, 80 and 300 μg oil/L, equivalent to 0.1, 0.8 and 3.0 μg TPAH/L). Acute and delayed mortality were observed at embryonic, larval, and juvenile stages with IC 50  = 2.2, 0.39, and 0.27 μg TPAH/L, respectively. Exposure to 0.1 μg TPAH/L had no negative effect on growth or survival. However, yolk sac larvae showed significant reduction in the outgrowth (ballooning) of the cardiac ventricle in the absence of other extracardiac morphological defects. Due to this propensity for latent sublethal developmental toxicity, we recommend an effect threshold of 0.1 μg TPAH/L for risk assessment models., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Site-specific DNA recombinases play a variety of biological roles, often related to the dissemination of antibiotic resistance, and are also useful synthetic biology tools. The simplest site-specific recombination systems will recombine any two cognate sites regardless of context. Other systems have evolved elaborate mechanisms, often sensing DNA topology, to ensure that only one of multiple possible recombination products is produced. The closely related resolvases from the Tn3 and γδ transposons have historically served as paradigms for the regulation of recombinase activity by DNA topology. However, despite many proposals, models of the multi-subunit protein-DNA complex (termed the synaptosome) that enforces this regulation have been unsatisfying due to a lack of experimental constraints and incomplete concordance with experimental data. Here, we present new structural and biochemical data that lead to a new, detailed model of the Tn3 synaptosome, and discuss how it harnesses DNA topology to regulate the enzymatic activity of the recombinase., (© The Author(s) 2022. Published by Oxford University Press on behalf of Nucleic Acids Research.)

In the present study, we investigated the possibility of identifying the source oils of exposed fish using ratios of bicyclic sesquiterpane (bicyclane) chemical biomarkers. In the event of an oil spill, identification of source oil(s) for assessment, or for litigation purposes, typically uses diagnostic ratios of chemical biomarkers to produce characteristic oil "fingerprints." Although this has been applied in identifying oil residues in sediments, water, and sessile filtering organisms, so far as we are aware this has never been successfully demonstrated for oil-exposed fish. In a 35-day laboratory trial, juvenile Lates calcarifer (barramundi or Asian seabass) were exposed, via the diet (1% w/w), to either a heavy fuel oil or to Montara, an Australian medium crude oil. Two-dimensional gas chromatography with high-resolution mass spectrometry and gas chromatography-mass spectrometry were then used to measure selected ratios of the bicyclanes to examine whether the ratios were statistically reproducibly conserved in the fish tissues. Six diagnostic bicyclane ratios showed high correlation (r 2  > 0.98) with those of each of the two source oils. A linear discriminatory analysis model showed that nine different petroleum products could be reproducibly discriminated using these bicyclane ratios. The model was then used to correctly identify the bicyclane profiles of each of the two exposure oils in the adipose tissue extracts of each of the 18 fish fed oil-enriched diets. From our initial study, bicyclane biomarkers appear to show good potential for providing reliable forensic fingerprints of the sources of oil contamination of exposed fish. Further research is needed to investigate the minimum exposure times required for bicyclane bioaccumulation to achieve detectable concentrations in fish adipose tissues and to determine bicyclane depuration rates once exposure to oil has ceased. Environ Toxicol Chem 2023;42:7-18. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC., (© 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.)

Murray cod Maccullochella peelii (Mitchell) have a key ecological role in ensuring the health of Australia's largest inland waterway, but many aspects surrounding its reproductive strategies in the wild are unknown. From 2015 to 2019 within the Northern Murray-Darling Basin, Australia, we used a combination of bio-telemetry and underwater imagery to quantify the behaviour of Murray cod across their breeding cycle in a natural riverine environment. In most years, breeding behaviour including nest site selection was observed from early-August and spawning from late-August through to late-October, which is considerably earlier than previously reported. There was a positive correlation between the onset of breeding behaviour and week-of-year, and spawning was correlated with moon-phase. Whilst some nesting sites were amongst woody debris and in hollow logs, the majority were located in shallow water on hard substrate underneath undercuts along the riverbank edge. Nests were frequently established in isolated and disconnected pools with little or no measurable flow, suggesting that river hydraulics is not a key component driving spawning of Murray cod across at least some areas of its range. Larvae were observed actively swimming and controlling their position within and near nests and used a scatter tactic when dispersing. We also established that disturbing nesting Murray cod had a negative impact on egg and larval survival. We suggest a review of current regulations to safeguard the long-term conservation of the species across all sections of its range., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

For nearly 200 years, the only natural source of the alcohol ambrein has been coproliths produced in about 1% of sperm whales and in related jetsam. However, the finding of ambrein in adipocere/faeces of human corpses, led us to hypothesise that ambrein might occur in the faeces of other mammals. Herein, we used a recently developed gas chromatography-mass spectrometry method, with suitable derivatisation of the hindered hydroxy group of ambrein, to screen a number of extracts of mammalian faeces. Minor proportions of ambrein were detected in digested human sewage sludge and in the dung of elephant, domestic cattle, giraffe and buffalo. Whether ambrein formation in the terrestrial species is associated with coprolith formation, is unknown, but solid deposits known as enteroliths and fecaliths occur in humans and some domestic animals.

Ambrein is found in ambergris, a coprolith occurring in the rectum of the sperm whale. In vitro , ambrein is produced by enzymatic cyclisation of squalene, via a monocyclic intermediate. However, little is known of the in vivo process. In order to find evidence for the reaction in vivo , a comparison was made of the δ 13 C relative isotopic ratios of ambrein in ambergris with those of co-occurring sterols. A statistically significant difference was noted. This suggests that ambrein originates via a different biosynthetic mechanism from that of the sterols. Examination of the minor constituents of a hydrogenolysed extract of ambergris revealed compounds with a bicyclic polypodane nucleus, rather than those with monocyclic structures. It is hypothesised that in vivo biosynthesis of ambrein proceeds, at least in some cases, via bacterial production of bicyclic polypodenols. The latter are known products of non-concerted squalene (or squalene oxide) cyclisations in other organisms.

The site-specific recombinase Tn3 resolvase initiates DNA strand exchange when two res recombination sites and six resolvase dimers interact to form a synapse. The detailed architecture of this intricate recombination machine remains unclear. We have clarified which of the potential dimer-dimer interactions are required for synapsis and recombination, using a novel complementation strategy that exploits a previously uncharacterized resolvase from Bartonella bacilliformis ("Bart"). Tn3 and Bart resolvases recognize different DNA motifs, via diverged C-terminal domains (CTDs). They also differ substantially at N-terminal domain (NTD) surfaces involved in dimerization and synapse assembly. We designed NTD-CTD hybrid proteins, and hybrid res sites containing both Tn3 and Bart dimer binding sites. Using these components in in vivo assays, we demonstrate that productive synapsis requires a specific "R" interface involving resolvase NTDs at all three dimer-binding sites in res. Synapses containing mixtures of wild-type Tn3 and Bart resolvase NTD dimers are recombination-defective, but activity can be restored by replacing patches of Tn3 resolvase R interface residues with Bart residues, or vice versa. We conclude that the Tn3/Bart family synapse is assembled exclusively by R interactions between resolvase dimers, except for the one special dimer-dimer interaction required for catalysis., (© 2020 The Authors. Molecular Microbiology published by John Wiley & Sons Ltd.)

Volatile and semi-volatile compounds account for the odors, long valued in the perfumery industry, of the natural product, ambergris. Here we demonstrate application of solid phase micro extraction (SPME) and gas chromatography-mass spectrometry (GC-MS) to headspace analysis of the volatiles and semi-volatiles of jetsam ambergris. The samples collected in 2017/2018, ranged from a black, sticky material from New Zealand, likely recently ejected from a sperm whale, to a white solid found on a beach in Chile and radiocarbon-dated previously to be about 1000 years old. The traces of volatile/semi-volatile compounds extracted included, odorous γ-dihydroionone and odor-free pristane (2,6,10,14-tetramethylpentadecane), as the major constituents. The ratios of these to one another and to many other minor constituents, varied, depending on sample color and age.

The objective of this study was to advance analytical methods for detecting oil sands process-affected water (OSPW) seepage from mining containments and discriminating any such seepage from the natural bitumen background in groundwaters influenced by the Alberta McMurray formation. Improved sampling methods and quantitative analyses of two groups of monoaromatic acids were employed to analyze OSPW and bitumen-affected natural background groundwaters for source discrimination. Both groups of monoaromatic acids showed significant enrichment in OSPW, while ratios of O 2 /O 4 containing heteroatomic ion classes of acid extractable organics (AEOs) did not exhibit diagnostic differences. Evaluating the monoaromatic acids to track a known plume of OSPW-affected groundwater confirmed their diagnostic abilities. A secondary objective was to assess anthropogenically derived artificial sweeteners and per- and polyfluoroalkyl substances (PFAS) as potential tracers for OSPW. Despite the discovery of acesulfame and PFAS in most OSPW samples, trace levels in groundwaters influenced by general anthropogenic activities preclude them as individual robust tracers. However, their inclusion with the other metrics employed in this study served to augment the tiered, weight of evidence methodology developed. This methodology was then used to confirm earlier findings of OSPW migrations into groundwater reaching the Athabasca River system adjacent to the reclaimed pond at Tar Island Dyke.

Jetsam ambergris, found on beaches worldwide, has always been assumed to originate as a natural product of sperm whales (Physeteroidea). However, only indirect evidence has ever been produced for this, such as the presence of whale prey remains in ambergris. Here, we extracted and analysed DNA sequences from jetsam ambergris from beaches in New Zealand and Sri Lanka, and sequences from ambergris of a sperm whale beached in The Netherlands. The lipid-rich composition of ambergris facilitated high preservation-quality of endogenous DNA, upon which we performed shotgun Illumina sequencing. Alignment of mitochondrial and nuclear genome sequences with open-access reference data for multiple whale species confirms that all three jetsam samples derived originally from sperm whales ( Physeter macrocephalus ). Shotgun sequencing here also provides implications for metagenomic insights into ambergris-preserved DNA. These results demonstrate significant implications for elucidating the origins of jetsam ambergris as a prized natural product, and also for the understanding of sperm whale metabolism and diet, and the ecological mechanisms underlying these coproliths.

To date, the only known occurrence of ambrein, an important perfumery organic molecule, is in coproliths found in about one in a hundred sperm whales. Jetsam ambergris coproliths from the whale are also found occasionally on beaches worldwide. Here we report on the surprising occurrence of ambrein in human adipocere. Adipocere is a waxy substance formed post-mortem during incomplete anaerobic decomposition of soft tissues. Adipocere samples obtained from grave exhumations were analysed using gas chromatography-mass spectrometry (GC-MS). In addition to the typical fatty acids of adipocere, lesser amounts of ambrein were identified in the samples, in abundances similar to those of the major accompanying faecal steroids. The distribution of these compounds suggests that ambrein was produced post-mortem during the microbial decomposition of faecal residues and tissues. It is assumed that the adipocere matrix of saturated fatty acidsaided the preservation of ambrein over extended periods of time, because adipocere is stable against degradation. The association of ambrein formation in ageing faecal material, under moist, oxygen-depleted conditions, now requires more attention in studies of other mammalian and geological samples. Indeed, ambrein and its transformation products may be useful novel chemical indicators of aged faecal matter and decomposed bodies.

Extracts of produced waters from five mature Norwegian Sea oil fields were examined as total organic extracts (TOEs) and after fractionation into operationally-defined 'polar' and 'apolar' fractions. The TOEs and fractions were examined by gas chromatography (GC), GC-mass spectrometry (GC-MS), two dimensional GC-MS (GC × GC-MS) and liquid chromatography with high-resolution spectrometry (LC-HRMS) techniques. Low molecular weight aromatics, phenols and other common petroleum-derived hydrocarbons were characterized and quantified in the TOEs and fractions. In addition, a range of more uncommon polar and apolar constituents, including those likely derived from production chemicals, such as trithiolane, imidazolines and quaternary amine compounds (so-called 'quats'), were tentatively identified, using GC × GC-MS and LC-HRMS. The acute toxicity of the TOEs and subfractions was investigated using early life stages of the marine copepod Acartia tonsa. Toxicity varied significantly for different PW TOEs and subfractions. For some PWs, the toxicity was attributed mainly to the 'polar' components, while that of other PWs was associated mainly with the 'apolar' components. Importantly, the observed toxicity could not be explained by the presence of the commonly reported compounds only. Although, due to the vast chemical complexity even of the sub-fractions of the PW extracts, specific compounds driving the observed toxicity could be not be elucidated in this study, the proposed approach may suggest a way forward for future revisions of monitoring regimes for PW discharges., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

Ambergris, which is a coprolith originating from the sperm whale, has been found only rarely, but for centuries, as jetsam on beaches all over the world. There are no reliable data indicating how long such samples may have remained at sea, with unsubstantiated accounts suggesting maybe decades. Here, we obtained over forty jetsam samples, many collected on known dates, from mostly known beach locations across the globe. Such an inventory of verified jetsam ambergris is unprecedented. Each sample was characterised by analytical methods such as gas chromatography-mass spectrometry (GC-MS). We then determined the radiocarbon ages of some of the samples by well-described accelerator-MS techniques. Surprisingly, some samples of jetsam have remained in the environment for about a thousand years.

A multitude of recent studies have documented the detrimental effects of crude oil exposure on early life stages of fish, including larvae and embryos. While polycyclic aromatic hydrocarbons (PAHs), particularly alkyl PAHs, are often considered the main cause of observed toxic effects, other crude oil derived organic compounds are usually overlooked. In the current study, comprehensive two-dimensional gas chromatography coupled to mass spectrometry was applied to investigate the body burden of a wide range of petrogenic compounds in Atlantic haddock (Melanogrammus aeglefinus) and cod (Gadus morhua) embryos that had been exposed to sublethal doses of dispersed crude oil. Several groups of alkylated monoaromatic compounds (e.g. alkyl tetralins, indanes and alkyl benzenes), as well as highly alkylated PAHs, were found to accumulate in the fish embryos upon crude oil exposure. To investigate the toxicity of the monoaromatic compounds, two models (1-isopropyl-4-methyltetralin and 1-isopropyl-4-methylindane) were synthesized and shown to bioaccumulate and cause delayed hatching in developing embryos. Minor developmental effects, including craniofacial and jaw deformations and pericardial edemas, were also observed at the highest studied concentrations of the alkylindane., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Previous studies of uptake and effects of nanoplastics by marine organisms have been conducted at what may be unrealistically high concentrations. This is a consequence of the analytical challenges in tracking plastic particles in organisms at environmentally relevant concentrations and highlights the need for new approaches. Here, we present pulse exposures of 14 C-radiolabeled nanopolystyrene to a commercially important mollusk, Pecten maximus, at what have been predicted to be environmentally relevant concentrations (<15 μg L -1 ). Uptake was rapid and was greater for 24 nm than for 250 nm particles. After 6 h, autoradiography showed accumulation of 250 nm nanoplastics in the intestine, while 24 nm particles were dispersed throughout the whole-body, possibly indicating some translocation across epithelial membranes. However, depuration was also relatively rapid for both sizes; 24 nm particles were no longer detectable after 14 days, although some 250 nm particles were still detectable after 48 days. Particle size thus apparently influenced the biokinetics and suggests a need for chronic exposure studies. Modeling extrapolations indicated that it could take 300 days of continued environmental exposure for uptake to reach equilibrium in scallop body tissues although the concentrations would still below 2.7 mg g -1 . Comparison with previous work in which scallops were exposed to nonplastic (silver) nanomaterials of similar size (20 nm), suggests that nanoparticle composition may also influence the uptake tissue distributions somewhat.

Jetsam ambergris, found washed ashore on beaches, is an environmentally modified form of a natural product of Sperm whales which sometimes develops a pleasant odour. Odorous samples have proved valuable in perfumery. Identification of jetsam ambergris by analysis of organic-soluble extracts by Fourier transform infra-red spectroscopy (FTIR) and of derivatised samples by gas chromatography-mass spectrometry (GC-MS) has already been shown. Here, we describe a different method, in which characteristic alkenic protons and carbon atoms of the major constituent ambrein, were identified in whole extracts using nuclear magnetic resonance spectroscopy (NMR). The advantages of employing NMR spectroscopy included rapidity, reduced losses of volatiles compared to GC-MS and detection of non-GC amenable constituents. However, the identities and quantities of co-occurring individual components (e.g. steroids) could not easily be assigned in the unfractionated extracts by NMR spectroscopy, whereas they were by GC-MS, so an approach combining FTIR, GC-MS and NMR spectroscopic methods is advocated.

Petroleum acids, often called 'Naphthenic Acids' (NA), enter the environment in complex mixtures from numerous sources. These include from Produced and Process-Affected waters discharged from some oil industry activities, and from the environmental weathering of spilled crude oil hydrocarbons. Here, we test the hypothesis that individual NA within the complex mixtures can induce developmental abnormalities in fish, by screening a range of individual acids, with known chemical structures. Sixteen aromatic NA were tested using a Thamnocephalus platyrus (beavertail fairyshrimp) assay, to establish acute toxicity. Toxicities ranged from 568 to 8 μM, with the methylbiphenyl acid, 4-(p-tolyl)benzoic acid, most toxic. Next, five of the most toxic monoacids and for comparison, a diacid, were assayed using Danio rerio (zebrafish) embryos to test for lethality and developmental abnormalities. The toxicities were also predicted using Admet predictor™ software. Exposure to the five monoacids produced deformities in zebrafish embryos in a dose-dependent manner. Thus, exposure to 4-(p-tolyl)benzoic acid produced abnormalities in >90% of the embryos at concentrations of <1 μM; exposure to dehydroabietic acid caused pericardial edema and stunted growth in 100% of the embryos at 6 μM and exposure to pyrene-1-carboxylic acid caused 80% of embryos to be affected at 3 μM. The findings of this preliminary study therefore suggest that some aromatic acids are targets for more detailed mechanistic studies of mode of action. The results should help to focus on those NA which may be important for monitoring in oil industry wastewaters and polluted environmental samples., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Anaerobic biotransformation of petroleum hydrocarbons is an important alteration mechanism, both subsurface in geological reservoirs, in aquifers and in anoxic deep sea environments. Here we report the resolution and identification, by comprehensive two-dimensional gas chromatography-mass spectrometry (GC×GC-MS), of complex mixtures of aromatic acid and diacid metabolites of the anaerobic biodegradation of many crude oil hydrocarbons. An extended range of metabolites, including alkylbenzyl, alkylindanyl, alkyltetralinyl, alkylnaphthyl succinic acids and alkyltetralin, alkylnaphthoic and phenanthrene carboxylic acids, is reported in samples from experiments conducted under sulfate-reducing conditions in a microcosm over two years. The range of metabolites identified shows that the fumarate addition mechanism applies to the alteration of hydrocarbons with up to C 8 alkylation in monoaromatics and that functionalisation of up to three ring aromatic hydrocarbons with at least C 1 alkylation occurs. The GC×GC-MS method might now be applied to the identification of complex mixtures of metabolites in samples from real environmental oil spills., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Many environmental matrices contaminated with organic pollutants derived from crude oil or degraded petroleum contain mixtures so complex that they are typically unresolved by conventional analytical techniques such as gas chromatography. The resulting chromatographic features have become known as 'humps' or unresolved complex mixtures (UCMs). These UCMs often dominate the organic contaminants of polluted environmental samples: for example, in oil sands produced water up to 150mgL -1 of 'naphthenic acids' appear as UCMs when examined by gas chromatography as the esters. In oil-contaminated mussels, aromatic hydrocarbon UCMs may comprise almost all of the total toxic hydrocarbons, with over 7000μgg -1 dry weight reported in some samples. Over the last 25 years, efforts to resolve and thus identify, or at least to produce average structures, for some UCM components, have proved fruitful. Numerous non-polar UCM hydrocarbons and more polar UCM acids have been identified, then synthesised or purchased from commercial suppliers. As UCMs have been proposed to represent a risk to aquatic organisms, the need for assessment of the ecotoxicological effects and characterisation of the mode of action (MoA) of these environmental pollutants has arisen. In the present study, several chemicals with structures typical of those found in some UCMs, were assessed for their potential to disrupt membrane integrity, inhibit metabolic activity, activate the aryl hydrocarbon receptor (AhR), and activate the estrogen receptor (ER) in primary rainbow trout hepatocytes (Oncorhynchus mykiss). These endpoints were determined in order to screen for common toxic modes of action (MoA) in this diverse group of chemicals. The results from the in vitro screening indicated that of the endpoints tested, the predominant toxic MoA was cytotoxicity. EC 50 values for cytotoxicity were obtained for 16 compounds and ranged from 77μM-24mM, whereof aliphatic monocyclic acids, monoaromatic acids, polycyclic monoaromatic acids and alkylnaphthalenes were the most toxic. The observed cytotoxicity of the chemicals correlated well with the hydrophobicity (LogK OW ) suggesting that the toxicity was predominantly due to a non-specific MoA. Interestingly, two compounds induced the ER-mediated production of vitellogenin (Vtg) and six compounds induced the AhR-mediated Ethoxyresorufin-O-deethylase (EROD) enzymatic activity to >20% of the positive control; by doing so suggesting that they may act as ER or AhR agonists in fish. The heterogeneous group of 'UCM compounds' tested exhibited multiple MoA that may potentially cause adverse effects in fish. Additional studies to determine if these compounds may cause adverse effects in vivo at environmentally relevant concentrations, are warranted to identify if such compounds are indeed of potential environmental concern., (Copyright © 2017 Elsevier B.V. All rights reserved.)

We describe determination of the dichloromethane-soluble components of 12 samples of the natural product, ambergris, using capillary gas chromatography-mass spectrometry (GC-MS). Ambergris is produced in vivo in about 1% of Sperm whales and is used in perfumery and for odour fixation. Whilst descriptions of ambergris chemistry appeared until about 40 years ago, few accounts of analyses of whole extracts of multiple samples of ambergris by GC-MS have been published before. As expected, our analyses revealed that the major component (up to 97% of the dichloromethane-soluble material) was ambrein, with co-occurring, variable proportions of steroids. Moreover, we report apparently for the first time, mass spectra and retention indices of derivatised ambrein. These data should now allow reliable, rapid confirmation of even small amounts of jetsam, archived museum and customs samples of ambergris and an assessment of ambergris 'quality'.

The present study tested the hypothesis of no delayed sublethal effects of mild angling and release on the feeding, growth, somatic condition and gonadal development of golden perch Macquaria ambigua during gametogenesis. Subsamples of adult M. ambigua (n = 17-21 of 207), originally captured from the wild and stocked into ten 0·1 ha earthen ponds, were angled and released during early and late gametogenesis. Wild samples that were concurrently collected throughout the experiment underwent rapid and synchronous gonadal development and many spawned. While no spawning occurred in the ponds, most M. ambigua underwent normal gonadal development to maturity, including the angled fish. Angled fish also fed, maintained condition and actually grew faster than non-angled captive controls. Although females that were angled during late gametogenesis more readily ingested and retained baited hooks, neither their subsequent condition nor gonadal development was significantly affected. The predominance of null results was attributed to the combined effects of the flexible reproductive strategy of M. ambigua, the benignness of mouth hooking and immediate release, and possible methodological issues arising from differential hooking success of more aggressive and resilient individuals. The findings support earlier catch-and-release research, but contrast with reports of acute reproductive effects following capture and handling for aquaculture broodstock. This discrepancy highlights the need for research to specifically address welfare questions relevant to recreational fisheries across various species and angling scenarios., (© 2017 The Fisheries Society of the British Isles.)

Identification of the heteroatom (nitrogen, sulfur, and oxygen)-containing compounds of petroleum is of key importance when considering industrial and environmental issues associated with crude oil production. The more commonly performed methods of crude oil fractionation are often insufficient in the extent to which they separate oils, not allowing defined "molecular" fractions to be obtained. Methods capable of performing a class type separation are uncommon and are often extensive and resource and time intensive. Here we report a method for the separation of crude oils into discrete compound classes. The method utilizes both ion exchange and normal phase chromatography to generate fractions of saturated hydrocarbons, aromatic hydrocarbons, basic compounds, naphthenic acids, and other oxygen-containing species, carbazoles, sulfones, and thiophenes from small crude oil samples (∼0.5 g). Assessment of method selectivity with a suite of model compounds has shown the fractions to be well-defined, with classes of model compounds isolated within discrete fractions. Application of the method to five crude oils of varying API gravity (12.1-38.3°) demonstrates a potential for wide-ranging use. Sample recoveries were high (77-98%) with simple evaporative losses correlating closely with total sample loss. Repeatability was also high, demonstrated by triplicate analyses of model compound mixtures, oils spiked with model compounds and oils alone. Separation selectivity was further demonstrated by application of the scheme to the Alaska North Slope (ANS) crude oil and analysis of fractions by comprehensive two-dimensional gas-chromatography mass-spectrometry (GC × GC/MS) and/or liquid-chromatography high-resolution accurate-mass mass-spectrometry methods (LC-HRAM-MS). Isolation of discrete fractions then allowed excellent separation (by LC and GC methods) of carbazole, dibenzothiophene, fluorenones, xanthones, and quinoline fractions. Individual parent and C 1-5 alkyl homologues were easily separated (GC × GC/MS), allowing high-quality mass spectra (EI) to be obtained for the individual compounds in many cases. Analysis of fractions by GC × GC/MS also allowed a series of thioxanones to be identified.

It has been hypothesised that, if ingested, plastic debris could act as vector for the transfer of chemical contaminants from seawater to organisms, yet modelling suggest that, in the natural environment, chemical transfer would be negligible compared to other routes of uptake. However, to date, the models have not incorporated consideration of the role of gut surfactants, or the influence of pH or temperature on desorption, whilst experimental work has shown that these factors can enhance desorption of sorbed contaminants several fold. Here, we modelled the transfer of sorbed organic contaminants dichlorodiphenyltrichloroethane (DDT), phenanthrene (Phe) and bis-2-ethylhexyl phthalate (DEHP) from microscopic particles of polyvinylchloride (PVC) and polyethylene (PE) to a benthic invertebrate, a fish and a seabird using a one-compartment model OMEGA (Optimal Modelling for EcotoxicoloGical Applications) with different conditions of pH, temperature and gut surfactants. Environmental concentrations of contaminants at the bottom and the top of published ranges were considered, in combination with ingestion of either 1 or 5% by weight of plastic. For all organisms, the combined intake from food and water was the main route of exposure for Phe, DEHP and DDT with a negligible input from plastic. For the benthic invertebrate, predictions including the presence of contaminated plastic resulted in very small increases in the internal concentrations of DDT and DEHP, while the net change in the transfer of Phe was negligible. While there may be scenarios in which the presence of plastic makes a more important contribution, our modelling study suggests that ingestion of microplastic does not provide a quantitatively important additional pathway for the transfer of adsorbed chemicals from seawater to biota via the gut., (Copyright © 2016. Published by Elsevier Ltd.)

The acid-extractable organic compounds (AEOs), including naphthenic acids (NAs), present within oil sands process-affected water (OSPW) receive great attention due to their known toxicity. While recent progress in advanced separation and analytical methodologies for AEOs has improved our understanding of the composition of these mixtures, little is known regarding any variability (i.e., spatial, temporal) inherent within, or between, tailings ponds. In this study, 5 samples were collected from the same location of one tailings pond over a 2-week period. In addition, 5 samples were collected simultaneously from different locations within a tailings pond from a different mine site, as well as its associated recycling pond. In both cases, the AEOs were analyzed using SFS, ESI-MS, HRMS, GC×GC-ToF/MS, and GC- & LC-QToF/MS (GC analyses following conversion to methyl esters). Principal component analysis of HRMS data was able to distinguish the ponds from each other, while data from GC×GC-ToF/MS, and LC- and GC-QToF/MS were used to differentiate samples from within the temporal and spatial sample sets, with the greater variability associated with the latter. Spatial differences could be attributed to pond dynamics, including differences in inputs of tailings and surface run-off. Application of novel chemometric data analyses of unknown compounds detected by LC- and GC-QToF/MS allowed further differentiation of samples both within and between data sets, providing an innovative approach for future fingerprinting studies., (Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.)

The presence of a di-unsaturated highly branched isoprenoid (HBI) lipid biomarker (diene II) in Southern Ocean sediments has previously been proposed as a proxy measure of palaeo Antarctic sea ice. Here we show that a source of diene II is the sympagic diatom Berkeleya adeliensis Medlin. Furthermore, the propensity for B. adeliensis to flourish in platelet ice is reflected by an offshore downward gradient in diene II concentration in >100 surface sediments from Antarctic coastal and near-coastal environments. Since platelet ice formation is strongly associated with super-cooled freshwater inflow, we further hypothesize that sedimentary diene II provides a potentially sensitive proxy indicator of landfast sea ice influenced by meltwater discharge from nearby glaciers and ice shelves, and re-examination of some previous diene II downcore records supports this hypothesis. The term IPSO25-Ice Proxy for the Southern Ocean with 25 carbon atoms-is proposed as a proxy name for diene II.

In a previous study, we found a dose-dependent synergistic effect in recombinant yeast stably transfected with the human androgen receptor (AR), in response to co-exposure to testosterone and a commercially-available lubricant (engine) oil for cars. As there is relatively little knowledge on synergistic toxic effects and causative compounds, particularly for the androgenic system, the objective of the present study was to investigate this oil in more detail. The oil was fractionated into SARA fractions (so-called 'saturates', 'aromatics', 'resins', and 'asphaltenes') by open column chromatography. Surprisingly, when exposing the recombinant AR yeast to testosterone in combination with the separate SARA fractions, the synergistic effect could not be reproduced fully. After pooling the fractions again however, the full synergism returned. From subsequent exposures to combinations of two or three SARA fractions, it appeared that both the 'saturates' and the 'resins' fraction were required for obtaining the synergistic response with testosterone. This clearly demonstrates a synergistic effect related to the androgenic system caused by the joint action of at least three chemically-distinct compounds, or groups of compounds (i.e. testosterone, 'resins' and 'saturates'). Although detailed chemical analyses could not reveal the identity of the causative compounds and the in vivo relevance of the present results remains unclear, the results do add to the growing body of evidence on the potentially extremely complex character of mixture effects., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Naphthenic acids (NAs) are among the most toxic organic pollutants present in oil sands process waters (OSPW) and enter marine and freshwater environments through natural and anthropogenic sources. We investigated the effects of the acid extractable organic (AEO) fraction of OSPW and individual surrogate NAs, on maximum photosynthetic efficiency of photosystem II (PSII) (FV/FM) and cell growth in Emiliania huxleyi and Chlorella vulgaris as representative marine and freshwater phytoplankton. Whilst FV/FM in E. huxleyi and C. vulgaris was not inhibited by AEO, exposure to two surrogate NAs: (4'-n-butylphenyl)-4-butanoic acid (n-BPBA) and (4'-tert-butylphenyl)-4-butanoic acid (tert-BPBA), caused complete inhibition of FV/FM in E. huxleyi (≥10 mg L(-1)n-BPBA; ≥50 mg L(-1)tert-BPBA) but not in C. vulgaris. Growth rates and cell abundances in E. huxleyi were also reduced when exposed to ≥10 mg L(-1)n- and tert-BPBA; however, higher concentrations of n- and tert-BPBA (100 mg L(-1)) were required to reduce cell growth in C. vulgaris. AEO at ≥10 mg L(-1) stimulated E. huxleyi growth rate (p ≤ 0.002), yet had no apparent effect on C. vulgaris. In conclusion, E. huxleyi was generally more sensitive to NAs than C. vulgaris. This report provides a better understanding of the physiological responses of phytoplankton to NAs which will enable improved monitoring of NA pollution in aquatic ecosystems in the future., (Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Cosmetic products, such as facial scrubs, have been identified as potentially important primary sources of microplastics to the marine environment. This study characterises, quantifies and then investigates the sorptive properties of plastic microbeads that are used as exfoliants in cosmetics. Polyethylene microbeads were extracted from several products, and shown to have a wide size range (mean diameters between 164 and 327 μm). We estimated that between 4594 and 94,500 microbeads could be released in a single use. To examine the potential for microbeads to accumulate and transport chemicals they were exposed to a binary mixture of (3)H-phenanthrene and (14)C-DDT in seawater. The potential for transport of sorbed chemicals by microbeads was broadly similar to that of polythene (PE) particles used in previous sorption studies. In conclusion, cosmetic exfoliants are a potentially important, yet preventable source of microplastic contamination in the marine environment., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Identification of individual petroleum acids ("naphthenic" acids, NA) has proved challenging for decades, due to the extreme complexity of many petroleum acid mixtures. This has hindered detailed understanding of the role of NA in petroleum generation and oil production processes, refinery corrosion, as wood preservatives, and as environmental toxicants. Some recent advances have been made due to improved chromatographic separation of esters of the acids by multidimensional gas chromatography-mass spectrometry (GC × GC-MS), but relatively few reference spectra of esters are available for comparison. Here we report a complementary method based on a combination of a modified historical approach of converting NA to the corresponding hydrocarbons, followed by analysis by GC × GC-MS. Many published spectra exist for reference hydrocarbons making comparisons of reference spectra with those of the unknowns, much more feasible. As an example, we report identification of over 30 individual bicyclic naphthenic acids as the bicyclane hydrocarbons. These include both fused and bridged acids possessing methyl, dimethyl, and ethyl alkyl substituents as well as some terpenoid-derived acids. The study provides the most comprehensive analysis of one of the major classes of NA (the bicyclic acids) to date. There is now clear potential for this method to be used for the structural elucidation of other unknown acids (e.g., oil sands acids) and functionalized biomarkers in complex mixtures.

Oil industry produced waters, such as the oils sands process-affected waters (OSPW) of Alberta, Canada, represent a challenge in terms of risk assessment and reclamation due to their extreme complexity, particularly of the organic chemical constituents, including the naphthenic acids (NA). The identification of numerous NA in single samples has raised promise for the use of NA distributions for profiling OSPW. However, monitoring of the success of containment is still difficult, due to the lack of knowledge of the homogeneity (or otherwise) of OSPW composition within, and between, different industry containments. Here we used GC×GC-MS to compare the NA of five OSPW samples from each of two different industries. Short-term temporal and pond-scale spatial variations in the distributions of known adamantane acids and diacids and other unknown tricyclic acids were examined and a statistical appraisal of the replicate data made. The presence/absence of individual acids easily distinguished the OSPW NA of one industry from those of the other. The proportions of tricyclic acids with different carbon numbers also varied significantly between the OSPW of the two industries. The pond-scale spatial variation in NA in OSPW samples was higher than the short-term (2 weeks) temporal variations. An OSPW sample from an aged pond was exceptionally high in the proportion of C15,16,17 compounds, possibly due to increased biotransformation. Such techniques could possibly also help to distinguish different sources of NA in the environment.

This paper presents chemical composition and aquatic toxicity characteristics of a commercial sample of naphthenic acids (NAs). Naphthenic acids are derived from the refining of petroleum middle distillates and can contribute to refinery effluent toxicity. NAs are also present in oil sands process-affected water (OSPW), but differences in the NAs compositions from these sources precludes using a common aquatic toxicity dataset to represent the aquatic hazards of NAs from both origins. Our chemical characterization of a commercial sample of NAs showed it to contain in order of abundance, 1-ring>2-ring>acyclic>3-ring acids (∼84%). Also present were monoaromatic acids (7%) and non-acids (9%, polyaromatic hydrocarbons and sulfur heterocyclic compounds). While the acyclic acids were only the third most abundant group, the five most abundant individual compounds were identified as C(10-14) n-acids (n-decanoic acid to n-tetradecanoic acid). Aquatic toxicity testing of fish (Pimephales promelas), invertebrate (Daphnia magna), algae (Pseudokirchneriella subcapitata), and bacteria (Vibrio fischeri) showed P. promelas to be the most sensitive species with 96-h LL50=9.0 mg L(-1) (LC50=5.6 mg L(-1)). Acute EL50 values for the other species ranged 24-46 mg L(-1) (EC50 values ranged 20-30 mg L(-1)). Biomimetic extraction via solid-phase-microextraction (BE-SPME) suggested a nonpolar narcosis mode of toxic action for D. magna, P. subcapitata, and V. fischeri. The BE analysis under-predicted fish toxicity, which indicates that a specific mode of action, besides narcosis, may be a factor for fishes., (Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Although bicyclic acids have been reported to be the major naphthenic acids in oil sands process-affected water (OSPW) and a well-accepted screening assay indicated that some bicyclics were the most acutely toxic acids tested, none have yet been identified. Here we show by comprehensive multidimensional gas chromatography-mass spectrometry (GC×GC-MS), that >100 C8-15 bicyclic acids are typically present in OSPW. Synthesis or purchase allowed us to establish the GC×GC retention times of methyl esters of numerous of these and the mass spectra and published spectra of some additional types, allowed us to identify bicyclo[2.2.1]heptane, bicyclo[3.2.1]octane, bicyclo[4.3.0]nonane, bicyclo[3.3.1]nonane and bicyclo[4.4.0]decane acids in OSPW and a bicyclo[2.2.2]octane acid in a commercial acid mixture. The retention positions of authentic bicyclo[3.3.0]octane and bicyclo[4.2.0]octane carboxylic acid methyl esters and published retention indices, showed these were also possibilities, as were bicyclo[3.1.1]heptane acids. Bicyclo[5.3.0]decane and cyclopentylcyclopentane carboxylic acids were ruled out in the samples analysed, on the basis that the corresponding alkanes eluted well after bicyclo[4.4.0]decane (latest eluting acids). Bicyclo[4.2.1]nonane, bicyclo[3.2.2]nonane, bicyclo[3.3.2]decane, bicyclo[4.2.2]decane and spiro[4.5]decane carboxylic acids could not be ruled out or in, as no authentic compounds or literature data were available. Mass spectra of the methyl esters of the higher bicyclic C12-15 acids suggested that many were simply analogues of the acids identified above, with longer alkanoate chains and/or alkyl substituents. Our hypothesis is that these acids represent the biotransformation products of the initially somewhat more bio-resistant bicyclanes of petroleum. Although remediation studies suggest that many bicyclic acids can be relatively quickly removed from suitably treated OSPW, examination by GC×GC-MS may show which isomers are affected most. Knowledge of the structures will allow the toxicity of any residual isomers to be calculated and measured., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Rationale: Characterising complex mixtures of organic compounds in polar fractions of heavy petroleum is challenging, but is important for pollution studies and for exploration and production geochemistry. Oil sands process-affected water (OSPW) stored in large tailings ponds by Canadian oil sands industries contains such mixtures., Methods: A polar OSPW fraction was obtained by silver ion solid-phase extraction with methanol elution. This was examined by numerous methods, including electrospray ionisation (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS) and ultra-high-pressure liquid chromatography (uHPLC)/Orbitrap MS, in multiple ionisation and MS/MS modes. Compounds were also synthesised for comparison., Results: The major ESI ionisable compounds detected (+ion mode) were C15-28 SO3 species with 3-7 double bond equivalents (DBE) and C27-28 SO5 species with 5 DBE. ESI-MS/MS collision-induced losses were due to water, methanol, water plus methanol and water plus methyl formate, typical of methyl esters of hydroxy acids. Once the fraction was re-saponified, species originally detected by positive ion MS, could be detected only by negative ion MS, consistent with their assignment as sulphur-containing hydroxy carboxylic acids. The free acid of a keto dibenzothiophene alkanoic acid was added to an unesterified acid extract of OSPW in known concentrations as a putative internal standard, but attempted quantification in this way proved unreliable., Conclusions: The results suggest the more polar acidic organic SO3 constituents of OSPW include C15-28  S-containing, alicyclic and aromatic hydroxy carboxylic acids. SO5 species are possibly sulphone analogues of these. The origin of such compounds is probably via further biotransformation (hydroxylation) of the related S-containing carboxylic acids identified previously in a less polar OSPW fraction. The environmental risks, corrosivity and oil flow assurance effects should be easier to assess, given that partial structures are now known, although further identification is still needed., (Copyright © 2014 John Wiley & Sons, Ltd.)

Rationale: The identification of key acid metabolites ('signature' metabolites) has allowed significant improvements to be made in our understanding of the biodegradation of petroleum hydrocarbons, in reservoir and in contaminated natural systems, such as aquifers and seawater. On this basis, anaerobic oxidation is now more widely accepted as one viable mechanism, for instance. However, identification of metabolites in the complex acid mixtures from petroleum degradation is challenging and would benefit from use of more highly resolving analytical methods., Methods: Comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry (GCxGC/TOFMS) with both nominal mass and accurate mass measurement was used to study the complex mixtures of aromatic acids (as methyl esters) in petroleum fractions., Results: Numerous mono- and di-aromatic acid isomers were identified in a commercial naphthenic acids fraction from petroleum and in an acids fraction from a biodegraded petroleum. In many instances, compounds were identified by comparison of mass spectral and retention time data with those of authentic compounds., Conclusions: The identification of a variety of alkyl naphthalene carboxylic and alkanoic and alkyl tetralin carboxylic and alkanoic acids, plus identifications of a range of alkyl indane acids, provides further evidence for 'signature' metabolites of biodegradation of aromatic petroleum hydrocarbons. Identifications such as these now offer the prospect of better differentiation of metabolites of bacterial processes (e.g. aerobic, methanogenic, sulphate-reducing) in polar petroleum fractions., (Copyright © 2014 John Wiley & Sons, Ltd.)

Polar organic compounds found in industrial process waters, particularly those originating from biodegraded petroleum residues, include 'naphthenic acids' (NA). Some NA have been shown to have acute toxicity to fish and also to produce sub-lethal effects. Whilst some of these toxic effects are produced by identifiable carboxylic acids, acids such as sulphur-containing acids, which have been detected, but not yet identified, may produce others. Therefore, in the present study, the sulphur-containing acids in oil sands process water were studied. A fraction (ca 12% by weight of the total NA containing ca 1.5% weight sulphur) was obtained by elution of methylated NA through an argentation solid phase extraction column with diethyl ether. This was examined by multidimensional comprehensive gas chromatography-mass spectrometry (GCxGC-MS) in both nominal and high resolution mass accuracy modes and by GCxGC-sulphur chemiluminescence detection (GCxGC-SCD). Interpretation of the mass spectra and retention behaviour of methyl esters of several synthesised sulphur acids and the unknowns allowed delimitation of the structures, but not complete identification. Diaromatic sulphur-containing alkanoic acids were suggested. Computer modelling of the toxicities of some of the possible acids suggested they would have similar toxicities to one another and to dehydroabietic acid. However, the sulphur-rich fraction was not toxic or estrogenic to trout hepatocytes, suggesting the concentrations of sulphur acids in this sample were too low to produce any such effects in vitro. Further samples should probably be examined for these compounds., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Microplastics have the potential to uptake and release persistent organic pollutants (POPs); however, subsequent transfer to marine organisms is poorly understood. Some models estimating transfer of sorbed contaminants to organisms neglect the role of gut surfactants under differing physiological conditions in the gut (varying pH and temperature), examined here. We investigated the potential for polyvinylchloride (PVC) and polyethylene (PE) to sorb and desorb (14)C-DDT, (14)C-phenanthrene (Phe), (14)C-perfluorooctanoic acid (PFOA) and (14)C-di-2-ethylhexyl phthalate (DEHP). Desorption rates of POPs were quantified in seawater and under simulated gut conditions. Influence of pH and temperature was examined in order to represent cold and warm blooded organisms. Desorption rates were faster with gut surfactant, with a further substantial increase under conditions simulating warm blooded organisms. Desorption under gut conditions could be up to 30 times greater than in seawater alone. Of the POP/plastic combinations examined Phe with PE gave the highest potential for transport to organisms., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The objective of this study was to identify chemical components that could distinguish chemical mixtures in oil sands process-affected water (OSPW) that had potentially migrated to groundwater in the oil sands development area of northern Alberta, Canada. In the first part of the study, OSPW samples from two different tailings ponds and a broad range of natural groundwater samples were assessed with historically employed techniques as Level-1 analyses, including geochemistry, total concentrations of naphthenic acids (NAs) and synchronous fluorescence spectroscopy (SFS). While these analyses did not allow for reliable source differentiation, they did identify samples containing significant concentrations of oil sands acid-extractable organics (AEOs). In applying Level-2 profiling analyses using electrospray ionization high resolution mass spectrometry (ESI-HRMS) and comprehensive multidimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOF/MS) to samples containing appreciable AEO concentrations, differentiation of natural from OSPW sources was apparent through measurements of O2:O4 ion class ratios (ESI-HRMS) and diagnostic ions for two families of suspected monoaromatic acids (GC × GC-TOF/MS). The resemblance between the AEO profiles from OSPW and from 6 groundwater samples adjacent to two tailings ponds implies a common source, supporting the use of these complimentary analyses for source identification. These samples included two of upward flowing groundwater collected <1 m beneath the Athabasca River, suggesting OSPW-affected groundwater is reaching the river system.

Rationale: As a by-product of oil sands extraction, large volumes of oil sands process water (OSPW) are generated, which are contaminated with a large range of water-soluble organic compounds. The acids are thought to be derived from hydrocarbons via natural biodegradation pathways such as α- and β-oxidation of alkyl substituents, which could produce mono- and diacids, for example. However, while several monoacids ('O2' species) have been identified, the presence of diacids (i.e. 'O4' species) has only been deduced from results obtained via Fourier transform infrared (FTIR) spectroscopy, Fourier transform ion cyclotron resonance high-resolution mass spectrometry (FTICR-HRMS) and nuclear magnetic resonance ((1)H-NMR) spectroscopy and the structures have never been confirmed., Methods: An extract of an OSPW from a Canadian tailings pond was analysed and the retention times and the electron ionization mass spectra of some analytes were compared with those of bis-methyl esters of authentic diacids by gas chromatography × gas chromatography/time-of-flight mass spectrometry (GCxGC/TOFMS) in nominal and accurate mass configurations., Results: Two diamondoid diacids (3-carboxymethyladamantane-1-carboxylic acid and adamantane-1,3-dicarboxylic acid) were firmly identified as their bis-methyl esters by retention time and mass spectral matching and several other structural isomers were more tentatively assigned. Diacids have substantially increased polarity over the hydrocarbon and monoacid species from which they probably derive: as late members of biodegradation processes they may be useful indicators of weathering and ageing, not only of OSPW, but potentially of crude oil residues more generally., Conclusions: Structures of O4 species in OSPW have been identified. This confirms pathways of microbial biodegradation, which were only postulated previously, and may be a further indication that remediation of OSPW toxicity can occur by natural microbial action. The presence and abundance of these diacids might therefore be useful as a measure of biodegradation and weathering., (Copyright © 2013 John Wiley & Sons, Ltd.)

Inadequate products, waste management, and policy are struggling to prevent plastic waste from infiltrating ecosystems [1, 2]. Disintegration into smaller pieces means that the abundance of micrometer-sized plastic (microplastic) in habitats has increased [3] and outnumbers larger debris [2, 4]. When ingested by animals, plastic provides a feasible pathway to transfer attached pollutants and additive chemicals into their tissues [5-15]. Despite positive correlations between concentrations of ingested plastic and pollutants in tissues of animals, few, if any, controlled experiments have examined whether ingested plastic transfers pollutants and additives to animals. We exposed lugworms (Arenicola marina) to sand with 5% microplastic that was presorbed with pollutants (nonylphenol and phenanthrene) and additive chemicals (Triclosan and PBDE-47). Microplastic transferred pollutants and additive chemicals into gut tissues of lugworms, causing some biological effects, although clean sand transferred larger concentrations of pollutants into their tissues. Uptake of nonylphenol from PVC or sand reduced the ability of coelomocytes to remove pathogenic bacteria by >60%. Uptake of Triclosan from PVC diminished the ability of worms to engineer sediments and caused mortality, each by >55%, while PVC alone made worms >30% more susceptible to oxidative stress. As global microplastic contamination accelerates, our findings indicate that large concentrations of microplastic and additives can harm ecophysiological functions performed by organisms., (Copyright © 2013 Elsevier Ltd. All rights reserved.)