Susan Bengtson Nash

Herbicide contamination and the potential impact to seagrass meadows in Hervey Bay, Queensland, Australia

Publisher: Elsevier BV

Date: 2005

DOI: 10.1016/J.MARPOLBUL.2004.10.045

Abstract: Low concentrations of herbicides (up to 70 ng l(-1)), chiefly diuron (up to 50 ng l(-1)) were detected in surface waters associated with inter-tidal seagrass meadows of Zostera muelleri in Hervey Bay, south-east Queensland, Australia. Diuron and atrazine (up to 1.1 ng g(-1) dry weight of sediment) were detected in the sediments of these seagrass meadows. Concentration of the herbicides diuron, simazine and atrazine increased in surface waters associated with seagrass meadows during moderate river flow events indicating herbicides were washed from the catchment to the marine environment. Maximum herbicide concentration (sum of eight herbicides) in the Mary River during a moderate river flow event was 4260 ng l(-1). No photosynthetic stress was detected in seagrass in this study during low river flow. However, with moderate river flow events, nearshore seagrasses are at risk of being exposed to concentrations of herbicides that are known to inhibit photosynthesis.

Spring Melt and the Redistribution of Organochlorine Pesticides in the Sea-Ice Environment: A Comparative Study between Arctic and Antarctic Regions

Publisher: American Chemical Society (ACS)

Date: 02-08-2017

DOI: 10.1021/ACS.EST.7B02481

Abstract: Complementary s ling of air, snow, sea-ice, and seawater for a range of organochlorine pesticides (OCPs) was undertaken through the early stages of respective spring sea-ice melting at coastal sites in northeast Greenland and eastern Antarctica to investigate OCP concentrations and redistribution during this time. Mean concentrations in seawater, sea-ice and snow were generally greater at the Arctic site. For ex le, α-HCH was found to have the largest concentrations of all analytes in Arctic seawater and sea-ice meltwater s les (224-253 and 34.7-48.2 pg·L

Establishment of the first humpback whale fibroblast cell lines and their application in chemical risk assessment

Publisher: Elsevier BV

Date: 10-2015

DOI: 10.1016/J.AQUATOX.2015.08.005

Abstract: This paper reports the first successful derivation and characterization of humpback whale fibroblast cell lines. Primary fibroblasts were isolated from the dermal connective tissue of skin biopsies, cultured at 37 °C and 5% CO2 in the standard mammalian medium DMEM/F12 supplemented with 10% fetal bovine serum (FBS). Of nine initial biopsies, two cell lines were established from two different animals and designated HuWa1 and HuWa2. The cells have a stable karyotype with 2n=44, which has commonly been observed in other baleen whale species. Cells were verified as being fibroblasts based on their spindle-shaped morphology, adherence to plastic and positive immunoreaction to vimentin. Population doubling time was determined to be ∼41 h and cells were successfully cryopreserved and thawed. To date, HuWa1 cells have been propagated 30 times. Cells proliferate at the tested temperatures, 30, 33.5 and 37 °C, but show the highest rate of proliferation at 37 °C. Short-term exposure to para,para'-dichlorodiphenyldichloroethylene (p,p'-DDE), a priority compound accumulating in southern hemisphere humpback whales, resulted in a concentration-dependent loss of cell viability. The effective concentration which caused a 50% reduction in HuWa1 cell viability (EC50 value) was approximately six times greater than the EC50 value for the same chemical measured with human dermal fibroblasts. HuWa1 exposed to a natural, p,p'-DDE-containing, chemical mixture extracted from whale blubber showed distinctively higher sensitivity than to p,p'-DDE alone. Thus, we provide the first cytotoxicological data for humpback whales and with establishment of the HuWa cell lines, a unique in vitro model for the study of the whales' sensitivity and cellular response to chemicals and other environmental stressors.

Airborne Microplastics in Indoor and Outdoor Environments of a Developing Country in South Asia: Abundance, Distribution, Morphology, and Possible Sources

Publisher: American Chemical Society (ACS)

Date: 28-11-2022

DOI: 10.1021/ACS.EST.2C05885

Abstract: Airborne microplastics (AMPs) have been reported in indoor and outdoor air in high-income countries and are expected to be a significant contributor to daily microplastic (MP) exposure for human beings. To date, there are only a handful of studies in lower-middle-income countries. In this study, AMPs from 5000 to 50 μm were s led across selected areas of Sri Lanka using an active s ling technique. Suspected AMPs were further characterized using Fourier transform infrared spectroscopy. MP concentrations were higher indoors compared to outdoor air (0.13-0.93, compared to 0.00-0.23 particles/m

Herbicides implicated as the cause of severe mangrove dieback in the Mackay region, NE Australia: consequences for marine plant habitats of the GBR World Heritage Area

Publisher: Elsevier BV

Date: 2005

DOI: 10.1016/J.MARPOLBUL.2004.10.040

Abstract: Herbicides, particularly diuron, were correlated with severe and widespread dieback of the dominant mangrove, Avicennia marina (Forsk.) Vierh. var. eucalyptifolia (Val.) N.C. Duke (Avicenniaceae), its reduced canopy condition, and declines in seedling health within three neighbouring estuaries in the Mackay region of NE Australia. This unusual species-specific dieback, first observed in the early 1990s, had gotten notably worse by 2002 to affect >30 km(2) of mangroves in at least five adjacent estuaries in the region. Over the past century, agricultural production has responded well to the demands of increasing population with improvements in farm efficiency assisted by significant increases in the use of agricultural chemicals. However, with regular and episodic river flow events, these chemicals have sometimes found their way into estuarine and nearshore water and sediments where their effects on marine habitats have been largely unquantified. Investigations over the last three years in the Mackay region provide compelling evidence of diuron, and possibly other agricultural herbicides, as the most likely cause of the severe and widespread mangrove dieback. The likely consequences of such dieback included declines in coastal water quality with increased turbidity, nutrients and sediment deposition, as well as further dispersal of the toxic chemicals. The implications of such findings are immense since they describe not only the serious deterioration of protected and beneficial mangrove habitat but also the potential for significant direct and indirect effects on other highly-valued estuarine and marine habitats in the region, including seagrass beds and coral reefs of the Great Barrier Reef lagoon. This article reviews all key findings and observations to date and describes the essential correlative and causative evidence.

Rapid exposure assessment of PSII herbicides in surface water using a novel chlorophyll a fluorescence imaging assay

Publisher: Elsevier BV

Date: 15-08-2008

DOI: 10.1016/J.SCITOTENV.2008.02.062

Abstract: Recently a new Maxi-Imaging-PAM (Max-I-PAM) instrument for phytotoxicity assessment via chlorophyll fluorescence imaging was introduced. This new instrument allows rapid detection of the effects of PS II inhibiting herbicides which are high use agricultural chemicals frequently detected in surface waters in Australia and elsewhere. Several studies have applied the new instrument for detection of phytotoxicants in water using microalgae suspensions however, these use preliminary protocols and to date no validated method is available for high throughput testing of environmental s les in 96-well plates. Here we developed and applied a new protocol allowing dose-response assessment of four s les within 2 h (8 dilutions in duplicate). The technique was found to be sensitive, with a detection limit of 2.3 ng l(-1) for the herbicide diuron when testing solid phase extracts (SPE) of 1000 ml water s les, and reproducible both between experiments (coefficient of variation (CV)=0.30) and within the 96-well plate (CV=0.06). Relative potencies were determined for four reference PS II impacting herbicides (diuron>hexazinone>atrazine>simazine). Extracts from 1000 ml environmental s les and diuron spiked ultrapure water as well as passive s ler extracts were evaluated and good agreement was found between diuron equivalent concentrations calculated from bioassay results (DEQ(IPAM)) and DEQ(CHEM) values calculated from LCMS chemical analysis of the four reference compounds in the same s les. Overall, the technique provides a valuable bioanalytical tool for rapid and inexpensive effects-based assessment of PS II impacting herbicides in environmental mixtures.

Dietary exposure of Antarctic krill to p,p′-DDE: Uptake kinetics and toxicological sensitivity in a key polar species

Publisher: Elsevier BV

Date: 04-2013

DOI: 10.1016/J.ENVPOL.2012.12.026

Abstract: This study evaluated the dietary uptake kinetics and sublethal toxicity of p,p'-dichlorodiphenyl dichloroethylene (p,p'-DDE) in Antarctic krill. The uptake rate constant (characterised by the seawater volume stripped of contaminant sorbed to algae) of 200 ± 0.32 mL g(-1) wet weight h(-1), average absorption efficiency of 86 ± 13% and very low elimination rate constant of 5 × 10(-6) ± 0.0031 h(-1) demonstrate the importance of feeding for p,p'-DDE bioaccumulation in Antarctic krill. Faecal egestion of unabsorbed p,p'-DDE of 8.1 ± 2.7% indicates that this pathway contributes considerably to p,p'-DDE sinking fluxes. A median internal effective concentration (IEC50) of 15 mmol/kg lipid weight for complete immobility indicates baseline toxicity and that Antarctic krill exhibit comparable toxicological sensitivity as temperate species under similar 10 d exposure conditions. These findings support the critical body residue approach and provide insight to the role of Antarctic krill in the biogeochemical cycling of p,p'-DDE in the Southern Ocean.

BASES Conference 2019 – Programme and Abstracts

Publisher: Informa UK Limited

Date: 08-11-2019

DOI: 10.1080/02640414.2019.1671688

Cytochrome P450 isozyme protein verified in the skin of southern hemisphere humpback whales (Megaptera novaeangliae): Implications for biochemical biomarker assessment

Publisher: Elsevier BV

Date: 04-2011

DOI: 10.1016/J.MARPOLBUL.2011.01.007

Abstract: Large mysticete whales represent a unique challenge for chemical risk assessment. Few epidemiological investigations are possible due to the low incidence of adult stranding events. Similarly their often extreme life-history adaptations of prolonged migration and fasting challenge exposure assumptions. Molecular biomarkers offer the potential to complement information yielded through tissue chemical analysis, as well as providing evidence of a molecular response to chemical exposure. In this study we confirm the presence of cytochrome P450 reductase (CPR) and cytochrome P450 isoenzyme 1A1 (CYP1A1) in epidermal tissue of southern hemisphere humpback whales (Megaptera novaeangliae). The detection of CYP1A1 in the integument of the humpback whale affords the opportunity for further quantitative non-destructive investigations of enzyme activity as a function of chemical stress.

Brief communication: Organochlorine pesticides in an archived firn core from Law Dome, East Antarctica

Publisher: Copernicus GmbH

Date: 26-10-2016

DOI: 10.5194/TC-10-2533-2016

Abstract: Abstract. Organochlorine pesticides (OCPs) were, for the first time, quantified in archived firn cores from East Antarctica representative of 1945–1957 and 1958–1967 (current era, C.E.). The core sections were melted under high-purity nitrogen atmosphere, and the meltwater was analysed. Methods allowed quantification of hexachlorocyclohexanes, heptachlor, trans-chlordane, dieldrin and endrin. While the core presented evidence of nominal contamination by modern-use chemicals, indicating handling and/or storage contamination, legacy OCP concentrations and deposition rates reported are orders of magnitude lower than those from Arctic regions, lending support for their validity. The study further provides a description of equipment used and suggests methods to overcome logistical challenges associated with trace organic contaminant detection in polar regions.

Lipid and fatty acid profiles of migrating Southern Hemisphere humpback whales Megaptera novaeangliae

Publisher: Inter-Research Science Center

Date: 19-12-2012

DOI: 10.3354/MEPS10059

Vertical distribution of lipids, fatty acids and organochlorine contaminants in the blubber of southern hemisphere humpback whales (Megaptera novaeangliae)

Publisher: Elsevier BV

Date: 03-3000

DOI: 10.1016/J.MARENVRES.2013.11.004

Abstract: Persistent organic pollutants (POPs), such as toxic lipophilic organochlorine (OC) compounds, accumulate in the blubber tissue of marine mammals. Toxicological s ling methods most frequently target only the superficial blubber layer. Vertical distribution of these contaminants through the blubber mantle may, however, not be homogenous and could reflect any dissemination of lipids and fatty acids (FAs). It is therefore critical to assess stratification patterns in a species of interest as a quality control measure for interpretation of toxicological data. Here, we analysed and compared the distribution of lipids, FAs, and OCs in the outermost and innermost blubber layer of southern hemisphere humpback whales. FA stratification was evident for short-chain (≤18) monounsaturated fatty acids (SC-MUFA), which were concentrated in the outer layer, consistent with the thermoregulatory role of this blubber layer. This stratification was, however, not reflected in OC distribution, which was similar in the inner and outer blubber layers of male humpback whales. By comparison, a noticeable gradient in total blubber lipid from the outer to the inner layer was observed in two lactating females, which coincided with higher lipid normalised contaminant levels in the inner layer. This study contains the most comprehensive assessment of humpback whale blubber stratification to date, however, further investigation of biological and ecological influencing factors is required.

Lifetime extension of humpback whale skin fibroblasts and their response to lipopolysaccharide (LPS) and a mixture of polychlorinated biphenyls (Aroclor)

Publisher: Springer Science and Business Media LLC

Date: 10-01-2019

DOI: 10.1007/S10565-018-09457-1

Altered developmental timing in early life stages of Antarctic krill (Euphausia superba) exposed to p,p′-DDE

Publisher: Elsevier BV

Date: 11-2011

DOI: 10.1016/J.SCITOTENV.2011.08.056

Abstract: Persistent organic pollutants (POPs) are persistent, toxic and bioaccumulative anthropogenic organic chemicals, capable of undergoing long range environmental transport to remote areas including the Antarctic. p,p'-dichlorodiphenyl dichloroethylene (p,p'-DDE) has been identified as a dominant POP accumulating in Antarctic krill (Euphausia superba), which is a key Southern Ocean species. This study examined the developmental toxicity of p,p'-DDE via aqueous exposure to Antarctic krill larvae. p,p'-DDE exposure was found to stimulate developmental timing in the first three larval stages of Antarctic krill, while extended monitoring of larvae after a five day exposure period had ended, revealed delayed inhibitory responses during development to the fourth larval stage. Stimulatory responses were observed from the lowest p,p'-DDE body residue tested of 10.1±3.0 μmol/kg (3.2±0.95 mg/kg) preserved wet weight, which is comparable to findings for temperate species and an order of magnitude lower than the exposure level found to cause sublethal behavioural effects in Antarctic krill. The delayed responses included increased mortality, which had doubled in the highest p,p'-DDE treatment (95±8.9% mortality at 20 μg/L p,p'-DDE) compared to the solvent control (44±11% mortality) 2 weeks after end of exposure. Development of surviving metanauplius larvae to calyptopis 1 larvae was delayed by 2 days in p,p'-DDE exposed larvae compared with untreated larvae. Finally, the developmental success of surviving p,p'-DDE exposed larvae was reduced by 50 to 75% compared to the solvent control (100% developmental success). The lowest observed effect concentration for all delayed effects was 1 μg/L, the lowest exposure concentration tested. These findings demonstrate the importance of delayed and indirect effects of toxicant exposure. Further, the findings of this study are important for environmental risk assessment of POPs in the Southern Ocean ecosystem and strongly highlight the significance of developmental endpoints for ecotoxicological testing.

Perfluorinated compounds in the Antarctic region: Ocean circulation provides prolonged protection from distant sources

Publisher: Elsevier BV

Date: 09-2010

DOI: 10.1016/J.ENVPOL.2010.05.024

Abstract: In order to investigate the extent to which Perfluorinated Contaminants (PFCs) have permeated the Southern Ocean food web to date, a range of Antarctic, sub-Antarctic and Antarctic-migratory biota were analysed for key ionic PFCs. Based upon the geographical distribution pattern and ecology of biota with detectable vs. non-detectable PFC burdens, an evaluation of the potential contributory roles of alternative system input pathways is made. Our analytical findings, together with previous reports, reveal only the occasional occurrence of PFCs in migratory biota and vertebrate predators with foraging ranges extending into or north of the Antarctic Circumpolar Current (ACC). Geographical contamination patterns observed correspond most strongly with those expected from delivery via hydrospheric transport as governed by the unique oceanographic features of the Southern Ocean. We suggest that hydrospheric transport will form a slow, but primary, input pathway of PFCs to the Antarctic region.

Behavioural sensitivity of a key Southern Ocean species (Antarctic krill, Euphausia superba) to p,p′-DDE exposure

Publisher: Elsevier BV

Date: 2012

DOI: 10.1016/J.ECOENV.2011.09.005

Abstract: Persistent organic pollutants (POPs) have been frequently measured throughout the Southern Ocean food web for which little information is available to assess the potential risks of POP exposure. The current study evaluated the toxicological sensitivity of a key Southern Ocean species, Antarctic krill, to aqueous exposure of p,p'-dichlorodiphenyl dichloroethylene (p,p'-DDE). Behavioural endpoints were used as indicators of sublethal toxicity. Immediate behavioural responses (partial immobility and tail flicking) most likely reflect neurotoxicity, while the p,p'-DDE body residue causing a median level of sublethal toxicity in Antarctic krill following 96h exposure (IEC50(sublethal toxicity)=3.9±0.21mmol/kg lipid weight) is comparable to those known to cause sublethal narcosis in temperate aquatic species. Critical body residues (CBRs) were more reproducible across tests than effective seawater concentrations. These findings support the concept of the CBR approach, that effective tissue residues are comparable across species and geographical ranges despite differences in environmental factors.

Variation in outer blubber lipid concentrations does not reflect morphological body condition in humpback whales

Publisher: The Company of Biologists

Date: 2020

DOI: 10.1242/JEB.213769

Abstract: An animal's body condition provides valuable information for ecophysiological studies, and is an important measure of fitness in population monitoring and conservation. While both the external body shape of an animal, as well as its internal tissues (i.e. fat content) can be used as measures of body condition, the relationship between the two is not always linear. We compared the morphological body condition (external metric obtained through aerial photogrammetry) of migrating humpback whales (Megaptera novaeangliae) with their outer blubber lipid concentration (internal metric obtained through blubber biopsy s ling) off south-west Australia early and late in the breeding season (spanning ∼4.5 months). The external body condition index of juvenile and adult humpback whales decreased with 26.9 (from 18.8 to −8.1%) and 12.0 percentage points (from 8.6 to −3.4%) between the early and late phase, respectively. In contrast, we found no intra-seasonal change in blubber lipid concentration, and no difference between reproductive classes (juveniles, adults and lactating females), however the small s le size prevented us from effectively testing these effects. Importantly however, in the 33 animals for which paired metrics were obtained, we found no correlation between the morphometric body condition index and the blubber lipid concentration of in idual whales. The lack of a linear relationship suggest that changes in outer blubber lipid concentration do not reflect external changes in body shape, thus limiting the utility of outer blubber lipid reserves for in idual body condition evaluation. The wider spectrum of change in body morphometry captured with aerial photogrammetry, supports the use of body morphometry as a reliable and well tested method.

A dynamic biophysical fugacity model of the movement of a persistent organic pollutant in Antarctic marine food webs

Publisher: CSIRO Publishing

Date: 2011

DOI: 10.1071/EN10108

Abstract: Environmental contextPersistent organic pollutants (POPs) are potentially toxic chemicals capable of long distance transport and are often found far from their source. Little is known of their behaviour in Antarctica, where the marine plankton food web is driven by strong seasonal variations in solar radiation. Here the first dynamic coupled ecosystem–fugacity model to describe how POPs distribute through the Antarctic environment is presented. The model is used to identify the important processes that govern the presence of hexachlorobenzene in Antarctic plankton. AbstractPolar regions can be repositories for many persistent organic pollutants (POPs). However, comparatively little is known of the movement and behaviour of POPs in Antarctic ecosystems. These systems are characterised by strong seasonal effects of light on plankton dynamics. This work describes a mass-conserving, fugacity-based dynamic model to describe the movement of POPs in the Antarctic physical and plankton systems. The model includes dynamic corrections for changes in the population volumes and the temperature dependence of the fugacity capacities, and was developed by coupling a dynamic Nutrient–Phytoplankton–Zooplankton–Detritus (NPZD) ecosystem model to fugacity models of the chemistry and biology of the Southern Ocean. The model is applied to the movement of hexachlorobenzene, a POP found in the Antarctic environment. The model predicts that the burden of HCB in the plankton varies with the seasonal cycle in Antarctic waters, and induces a seasonal variation in the biomagnification factor of zooplankton. This suggests that time series of POP concentrations in Antarctic biotic and abiotic systems should be measured over complete seasonal cycles. Furthermore, detritus is shown to be a key contributor to the movement of POPs in polar environments, linking physical and biological components of the model.

An Antarctic Research Station as a Source of Brominated and Perfluorinated Persistent Organic Pollutants to the Local Environment

Publisher: American Chemical Society (ACS)

Date: 16-12-2014

DOI: 10.1021/ES5048232

Abstract: This study investigated the role of a permanently manned Australian Antarctic research station (Casey Station) as a source of contemporary persistent organic pollutants (POPs) to the local environment. Polybrominated diphenyl ethers (PBDEs) and poly- and perfluoroalkylated substances (PFASs) were found in indoor dust and treated wastewater effluent of the station. PBDE (e.g., BDE-209 26-820 ng g(-1) dry weight (dw)) and PFAS levels (e.g., PFOS 3.8-2400 ng g(-1) (dw)) in dust were consistent with those previously reported in homes and offices from Australia, reflecting consumer products and materials of the host nation. The levels of PBDEs and PFASs in wastewater (e.g., BDE-209 71-400 ng L(-1)) were in the upper range of concentrations reported for secondary treatment plants in other parts of the world. The chemical profiles of some PFAS s les were, however, different from domestic profiles. Dispersal of chemicals into the immediate marine and terrestrial environments was investigated by analysis of abiotic and biotic matrices. Analytes showed decreasing concentrations with increasing distance from the station. This study provides the first evidence of PFAS input to Polar regions via local research stations and demonstrates the introduction of POPs recently listed under the Stockholm Convention into the Antarctic environment through local human activities.

Novel Use of Cell Profiling Technology to Visualize Mitochondrial Responses of Humpback Whale Fibroblasts to Chemical Exposure

Publisher: American Chemical Society (ACS)

Date: 05-06-2023

DOI: 10.1021/ACS.EST.2C07159

Application of a novel phytotoxicity assay for the detection of herbicides in Hervey Bay and the Great Sandy Straits

Publisher: Elsevier BV

Date: 2005

DOI: 10.1016/J.MARPOLBUL.2004.10.017

Abstract: A novel phytotoxicity assay was incorporated into an environmental assessment of Hervey Bay and the Great Sandy Straits, to investigate the role of run-off associated herbicides in the deteriorated health of intertidal seagrass meadows. Dose response curves of common herbicides were performed and their toxicity equivalents elucidated to assist in analysis. The results of the assay were reproducible and corresponded strongly with results of chemical analyses. The incorporation of the assay into the assessment of surface waters added an important aspect to the study by allowing investigation of the toxicity of cumulative herbicide concentrations and yielding biologically relevant data. The highest herbicide concentration detected during the study was equivalent to 0.23 microg l(-1) diuron a concentration known to inhibit photosynthetic efficiency of the assay biomaterial by approximately 3%.

A model to resolve organochlorine pharmacokinetics in migrating humpback whales

Publisher: Wiley

Date: 03-06-2014

DOI: 10.1002/ETC.2603

Abstract: Humpback whales are iconic mammals at the top of the Antarctic food chain. Their large reserves of lipid-rich tissues such as blubber predispose them to accumulation of lipophilic contaminants throughout their lifetime. Changes in the volume and distribution of lipids in humpback whales, particularly during migration, could play an important role in the pharmacokinetics of lipophilic contaminants such as the organochlorine pesticide hexachlorobenzene (HCB). Previous models have examined constant feeding and nonmigratory scenarios. In the present study, the authors develop a novel heuristic model to investigate HCB dynamics in a humpback whale and its environment by coupling an ecosystem nutrient-phytoplankton-zooplankton-detritus (NPZD) model, a dynamic energy budget (DEB) model, and a physiologically based pharmacokinetic (PBPK) model. The model takes into account the seasonal feeding pattern of whales, their energy requirements, and fluctuating contaminant burdens in the supporting plankton food chain. It is applied to a male whale from weaning to maturity, spanning 20 migration and feeding cycles. The model is initialized with environmental HCB burdens similar to those measured in the Southern Ocean and predicts blubber HCB concentrations consistent with empirical concentrations observed in a southern hemisphere population of male, migrating humpback whales. Results show for the first time some important details of the relationship between energy budgets and organochlorine pharmacokinetics.

Aqueous uptake and sublethal toxicity of p,p′-DDE in non-feeding larval stages of Antarctic krill (Euphausia superba)

Publisher: Elsevier BV

Date: 2012

DOI: 10.1016/J.ENVPOL.2011.09.022

Abstract: This study evaluated the toxicological sensitivity of non-feeding larval stages of a key Antarctic species (Antarctic krill, Euphausia superba) to p,p'-dichlorodiphenyl dichloroethylene (p,p'-DDE) exposure. The aqueous uptake clearance rate of 84 mL g(-1) preserved weight (p.w.) h(-1) determined for p,p'-DDE in Antarctic krill larvae is comparable to previous findings for small cold water crustaceans and five times slower than the rates reported for an hipod inhabiting warmer waters. Natural variations in larval physiology appear to influence contaminant uptake and larval krill behavioural responses, strongly highlighting the importance of time of measurement for ecotoxicological testing. Sublethal narcosis (immobility) was observed in larval Antarctic krill from p,p'-DDE body residues of 0.2 mmol/kg p.w., which is in agreement with findings for adult krill and temperate aquatic species. The finding of comparable body residue-based toxicity of p,p'-DDE between polar and temperate species supports the tissue residue approach for environmental risk assessment of polar ecosystems.

Detoxification enzyme activities (CYP1A1 and GST) in the skin of humpback whales as a function of organochlorine burdens and migration status

Publisher: Elsevier BV

Date: 10-2014

DOI: 10.1016/J.AQUATOX.2014.06.021

Abstract: The activities of glutathione-s-transferase (GST) and cytochrome P-450 1A1 (CYP1A1) enzymes were measured in freshly extracted epidermis of live-biopsied, migrating, southern hemisphere humpback whales (Megaptera novaeangliae). The two quantified enzyme activities did not correlate strongly with each other. Similarly, neither correlated strongly with any of the organochlorine compound groups previously measured in the superficial blubber of the s le biopsy core, likely reflecting the anticipated low levels of typical aryl-hydrocarbon receptor ligands. GST activity did not differ significantly between genders or between northward (early migration) or southward (late migration) migrating cohorts. Indeed, the inter-in idual variability in GST measurements was relatively low. This observation raises the possibility that measured activities were basal activities and that GST function was inherently impacted by the fasting state of the s led animals, as seen in other species. These results do not support the implementation of CYP1A1 or GST as effective biomarkers of organochlorine contaminant burdens in southern hemisphere populations of humpback whales as advocated for other cetacean species. Further investigation of GST activity in feeding versus fasting cohorts may, however, provide some insight into the fasting metabolism of these behaviourally adapted populations.

Air–Seawater Exchange of Organochlorine Pesticides in the Southern Ocean between Australia and Antarctica

Publisher: American Chemical Society (ACS)

Date: 12-07-2016

DOI: 10.1021/ACS.EST.6B01970

Abstract: This study contributes new data on the spatial variability of persistent organic pollutants in the Indian-Pacific sector of the Southern Ocean and represents the first empirical data obtained from this region in 25 years. Paired high-volume atmospheric and seawater s les were collected along a transect between Australia and Antarctica to investigate the latitudinal dependence of the occurrence and distribution of legacy organochlorine pesticides (OCPs) and the current use pesticide chlorpyrifos in the Southern Ocean. Dissolved ΣHCH and dieldrin concentrations decreased linearly with increasing latitude from 7.7 to 3.0 and from 1.0 to 0.6 pg·L(-1), respectively. There was no consistent trend observed in the latitudinal profile of atmospheric s les however, some compounds (such as dieldrin) showed reduced concentrations from 7.5-3.4 to 2.7-0.65 pg·m(-3) at the highest latitudes south of the Polar Front. Chlorpyrifos was found in s les from this area for the first time. Estimated air-seawater fugacity ratios and fluxes indicate a current net deposition between -3600 and -900, -6400 and -400, and -1400 and -200 (pg·m(-2)·d(-1)) for γ-HCH, dieldrin, and chlorpyrifos, respectively. These findings suggest that, under current climatic conditions, the Southern Ocean reservoir in the Indian-Pacific sector serves as an environmental sink rather than a source of OCPs to the atmosphere.

Persistent organohalogen contaminant burdens in Antarctic krill (Euphausia superba) from the eastern Antarctic sector: A baseline study

Publisher: Elsevier BV

Date: 15-12-2008

DOI: 10.1016/J.SCITOTENV.2008.08.034

Abstract: A baseline for persistent organohalogen compound (POC) accumulation in the Antarctic keystone species, Antarctic krill (Euphausia superba) has been established for a 50 degrees longitudinal range of the eastern Antarctic sector. S les of adult krill, caught from 12 sites distributed between 30 degrees and 80 degrees E (60-70 degrees S), were analysed for >100 organohalogen compounds including chlorinated pesticides, polychlorinated biphenyls (PCBs), polybrominated organic compounds and polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs). Organochlorine pesticides dominated measured krill contaminant burdens with hexachlorobenzene (HCB) as the single most abundant compound quantified. Krill HCB concentrations were comparable to those detected at this trophic level in both the Arctic and temperate northwest Atlantic, lending support for the hypothesis that HCB will approach global equilibrium at a faster rate than other POCs. Para, para'-dichlorodiphenylethene (p,p'-DDE) was detected at notable concentrations. Measurements of DDT and its degradation products provide an important baseline for monitoring the temporal and geographical influence of renewed, DDT usage for malaria-control in affected southern hemisphere countries. In contrast to the Arctic, PCBs did not feature prominently in contaminant burdens of Antarctic krill. The major commercial polybrominated diphenyl ether (PBDE) congeners -99 and -47 were quantified at low background levels with clear concentration spikes observed at around 70 degrees E , in the vicinity of modern, active research stations. The likelihood that local anthropogenic activities are supplementing low PBDE levels, delivered otherwise primarily via long range environmental transport, is discussed. The suspected naturally occurring brominated organic compound, 2,4,6-tribromoanisole (TBA), was a ubiquitous contaminant in all s les whereas the only PCDD/Fs quantifiable were trace levels of octachlorodibenzo-p-dioxin (OCDD) and 1,2,3,4,7,8/1,2,3,4,7,9-hexachlorodibenzofuran (HxCDF). With the aims of i) Generating a robust and broadly applicable POC auditing platform for the scarcely studied eastern Antarctic sector ii) Determining the compounds accumulating in Antarctic krill for further toxicity evaluation studies and iii) Establishing a baseline for Antarctic predator exposure to POCs, this study represents one of the most comprehensive reports of POC contamination of the Antarctic food web to date.

First detection of short-chain chlorinated paraffins (SCCPs) in humpback whales (Megaptera novaeangliae) foraging in Antarctic waters

Publisher: Elsevier BV

Date: 07-2019

DOI: 10.1016/J.ENVPOL.2019.04.103

Abstract: Short-chain chlorinated paraffins (SCCPs) are particularly prone to environmental dispersal through long range atmospheric transport. Consequently, they have been detected in biota and environmental matrices at both the North Pole and South Pole. This study shows the first detection of SCCPs in southern hemisphere humpback whales feeding in Antarctic waters. Blubber of specimens stranded along the Australian coastline was analysed and SCCPs were detected in 7 out of 9 in iduals. Levels of SCCPs detected in this study were generally low with concentrations up to only 46 ng/g lw. These results were significantly lower than those detected in Northern Hemisphere odontocetes from previous studies, although no reported burdens in northern hemisphere baleen whales are available for comparison. Both the highest level and lowest (<MDL) were measured in calves-of-the-year. Congener group profile in the s les showed that the predominant carbon chain length was C

The combined SPE:ToxY-PAM phytotoxicity assay; application and appraisal of a novel biomonitoring tool for the aquatic environment

Publisher: Elsevier BV

Date: 2005

DOI: 10.1016/J.BIOS.2004.09.019

Abstract: Mounting concerns regarding the environmental impact of herbicides has meant a growing requirement for accurate, timely information regarding herbicide residue contamination of, in particular, aquatic systems. Conventional methods of detection remain limited in terms of practicality due to high costs of operation and the specialised information that analysis provides. A new phytotoxicity bioassay was trialled for the detection of herbicide residues in filter-purified (Milli-Q) as well as natural waters. The performance of the system, which combines solid-phase extraction (SPE) with the ToxY-PAM dual-channel yield analyser (Heinz Walz GmbH), was tested alongside the traditional method of liquid chromatography-mass spectrometry (LC-MS). The assay methodology was found to be highly sensitive (LOD 0.1 ng L(-1) diuron) with good reproducibility. The study showed that the assay protocol is time effective and can be employed for the aquatic screening of herbicide residues in purified as well as natural waters.

The blubber adipocyte index: A nondestructive biomarker of adiposity in humpback whales (Megaptera novaeangliae)

Publisher: Wiley

Date: 04-06-2017

DOI: 10.1002/ECE3.2913

Uptake and Depuration Kinetics Influence Microplastic Bioaccumulation and Toxicity in Antarctic Krill (Euphausia superba)

Publisher: American Chemical Society (ACS)

Date: 03-02-2018

DOI: 10.1021/ACS.EST.7B05759

Abstract: The discarding of plastic products has led to the ubiquitous occurrence of microplastic particles in the marine environment. The uptake and depuration kinetics of ingested microplastics for many marine species still remain unknown despite its importance for understanding bioaccumulation potential to higher trophic level consumers. In this study, Antarctic krill ( Euphausia superba) were exposed to polyethylene microplastics to quantify acute toxicity and ingestion kinetics, providing insight into the bioaccumulation potential of microplastics at the first-order consumer level. In the 10 day acute toxicity assay, no mortality or dose-dependent weight loss occurred in exposed krill, at any of the exposure concentrations (0, 10, 20, 40, or 80% plastic diet). Krill exposed to a 20% plastic diet for 24 h displayed fast uptake (22 ng mg

University Of East London

Location: United Kingdom of Great Britain and Northern Ireland

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Discovery Projects - Grant ID: DP0666891

Start Date: 01-2006

End Date: 12-2009

Amount: $600,000.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP140100018

Start Date: 2014

End Date: 12-2017

Amount: $408,567.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE190100106

Start Date: 03-2019

End Date: 12-2019

Amount: $334,425.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP220101462

Start Date: 05-2023

End Date: 04-2027

Amount: $724,450.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE220100031

Start Date: 06-2022

End Date: 05-2023

Amount: $630,880.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP140100412

Start Date: 06-2015

End Date: 06-2020

Amount: $491,700.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP210200550

Start Date: 08-2023

End Date: 08-2026

Amount: $323,388.00

Funder: Australian Research Council