• Application of congener based multi-matrix profiling techniques to identify potential PCDD/F sources in environmental samples from the Burrishoole Catchment in the West of Ireland

      White, P.; McHugh, B.; Poole, R.; McGovern, E.; White, J.; Behan, P.; Foley, B.; Covaci, A. (Elsevier, 2014)
      Homologue and congener profiles of PCDD/Fs in eels, passive sampler and sediment extracts from the Burrishoole, a rural upland catchment on the western Irish seaboard were compared with potential PCDD sources. ΣPCDD/F levels in eels ranged from 2.9 to 25.9 pg g−1 wet weight, which are elevated compared to other Irish locations. The OCDD congener dominated the pattern of ΣPCDD/Fs in all matrices from Burrishoole. Passive samplers were successfully deployed to identify for the first time the presence in the water column of PCDD/Fs and dimethoxylated octachlorodiphenyl ether (diMeOoctaCDE), impurities found in pentachlorophenol (PCP) production. Principal component analysis (PCA) identified similarities between PCDD/F profiles in technical PCP mixtures and environmental samples from the Burrishoole region. Results strongly suggest residual PCDD contamination associated with historic local use of a dioxin contaminated product in the catchment area, with pentachlorophenol a strong candidate.
    • Assessment of biomarkers in Mytilus edulis to determine Good Environmental Status for implementation of MSFD in Ireland

      Giltrap, M.; Ronan, J.; Hardenberg, S.; Parkes, G.; McHugh, B.; McGovern, E.; Wilson, J.G. (Elsevier, 2013)
      Candidate OSPAR/ICES recommended biomarkers at the level of the individual in Mytilus edulis for determination of good environmental status for MSFD were evaluated against contaminant levels at sites around Ireland. The sites chosen ranged from moderate to low pollution levels, but the actual ranking of the sites varied according to the contaminant levels present. At the most contaminated site, Cork, 4 out of 16 contaminants exceeded the EAC, while at Shannon, no EACs were exceeded. The SOS assay suggested that Cork was the healthiest site with a LT50 of 17.6 days, while SOS for Shannon was 15.6 days. Likewise, condition factors varied among sites and did not always correspond to contaminant-based status. There may be uncertainty in assigning status around the not good:good boundary. This raises potential difficulties not only in the biomarker/contaminant load relationship but also in the reliability of the biomarkers themselves and hence barriers meeting compliance levels.
    • Biomarkers: are realism and control mutually exclusive in integrated pollution assessment?

      Wilson, J.G.; McHugh, B.; Giltrap, M. (Elsevier, 2014)
      The conventional view of pollution monitoring is that any choice is a trade-off between realism and precision, as the control over confounding variables decreases with the increasing degree of organization of the test system. Dublin Bay is subject to considerable anthropogenic pressures and there have been many attempts to quantify the status of the system at organizational levels from DNA strand breaks (Comet) to the system itself (Ecological Network analysis, ENA). Using Dublin Bay as an example, the data show there was considerable variability at all levels of organization. At intracellular level, Lysosome Membrane Stability (LMS, assessed by Neutral Red Retention, NRR) varied almost 4-fold with season and individual condition, while the community level AZTI Marine biotic Index (AMBI) had a similar range within a single, supposedly homogeneous, site. Overall, there was no evidence that biomarkers of the lower levels of organisation reduced the variability of the measure, despite the extra control over influencing variables, nor was there any evidence that variability was additive at higher levels of organisation. This poses problems for management, especially given the fixed limits of Ecological Quality Standards (EQSs). Clearly while the integrated approach to pollution monitoring does offer the potential to link effects across the organizational range, it should also be possible to improve their capability by widening the database for reference values, particularly at the higher level of organization, and by process models, including the confounding variables found in the field, for those at lower level.
    • Environmental occurrence, analysis, and toxicology of toxaphene compounds

      de Geus, H.-J.; Besselink, H.; Brouwer, A.; Klungsøyr, J.; McHugh, B.; Nixon, E.; Rimkus, G.G.; Wester, P.G.; de Boer, J. (1999)
      Toxaphene production, in quantities similar to those of polychlorinated biphenyls, has resulted in high toxaphene levels in fish from the Great Lakes and in Arctic marine mammals (up to 10 and 16 microg g-1 lipid). Because of the large variabiliity in total toxaphene data, few reliable conclusions can be drawn about trends or geographic differences in toxaphene concentrations. New developments in mass spectrometric detection using either negative chemical ionization or electron impact modes as well as in multidimensional gas chromatography have recently led researchers to suggest congener-specific approaches. Several nomenclature systems have been developed for toxaphene compounds. Although all systems have specific advantages and limitations, it is suggested that an international body, such as the International Union of Pure and Applied Chemistry, make an attempt to obtain uniformity in the literature. Toxicologic information on individual chlorobornanes is scarce, but some reports have recently appeared. Neurotoxic effects of toxaphene exposure such as those on behavior and learning have been reported. Technical toxaphene and some individual congeners were found to be weakly estrogenic in in vitro test systems; no evidence for endocrine effects in vivo has been reported. In vitro studies show technical toxaphene and toxaphene congeners to be mutagenic. However, in vivo studies have not shown genotoxicity; therefore, a nongenotoxic mechanism is proposed. Nevertheless, toxaphene is believed to present a potential carcinogenic risk to humans. Until now, only Germany has established a legal tolerance level for toxaphene--0.1 mg kg-1 wet weight for fish.
    • In vitro and in vivo tumor promoting potency of technical toxaphene, UV-irradiated toxaphene, and biotransformed toxaphene

      Besselink, H.T.; Nixon, E.; McHugh, B.; Klungsøyr, J.; Brouwer, A. (2000)
      Toxaphene, a complex mixture of polychlorinated camphenes, was first introduced in 1945 by Hercules Co. as Hercules 3965. Until the mid 1980s, it was mass produced and widely used as an insecticide, and was also used as a piscicide to control rough fish in various water systems. The lipophilic, persistent, and volatile nature of toxaphene has contributed to its global dispersion throughout the fresh water and marine environment. In addition to bioaccumulation in biota inhabiting these regions, it is also been detected in humans. Human exposure mainly occurs through the consumption of toxaphene contaminated fish. Information on the carcinogenicity and general toxicology of weathered and biotransformed TT would be of major interest. To mimic the weathered toxaphene found in fish, we developed a so-called 'realistic exposure' procedure for toxaphene. This procedure makes use of cod that were exposed to TT. Toxaphene residues that were extracted from cod liver (CLE), were then used in in vitro and in vivo studies to obtain information on its tumor promoting potency. Besides CLE, we also studied the tumor promoting properties of UV-irradiated toxaphene (UVT) and TT.
    • MATT: Monitoring, Analysis and Toxicity of Toxaphene: improvement of analytical methods

      de Boer, J.; Klungsøyr, J.; Nesje, G.; Meier, S.; McHugh, B.; Nixon, E.; Rimkus, G.G. (1999)
      The European Research Project MATT (Investigation into the Monitoring, Analysis and Toxicity of Toxaphene) started in 1997 and had the objective to provide information on toxicological risks to the consumer of toxaphene residues in fish from European waters. This report includes information on the analytical block of the project, which comprised three studies.
    • Mercury assessment in the marine environment: assessment criteria comparison (EAC/EQS) for mercury

      OSPAR Commission; McHugh, B.; Berbee, R.; Farmer, E.; Fryer, R.; Green, N.; Larsen, M.M.; Webster, L.; Lepom, P.; McGovern, E.; et al. (OSPAR Commission, 2016)
      Mercury is known for its worldwide environmental impact. It is addressed by several existing international agreements addressing atmospheric emissions (CLRTAP), the marine environment (OSPAR, HELCOM, Barcelona, Bucharest), waste (Basel), and export of chemicals (Rotterdam). It can be brought into the biosphere by humans by two different mechanisms: 1) intentional extraction and use, and 2) as a natural constituent in other materials. Mercury is extremely toxic to both man and biota and can be transformed within the aquatic environment into more toxic organic compounds (e.g. methyl mercury). A main pathway of mercury to the sea is atmospheric and it can be carried long distances from its source. The primary risk to the general population is exposure to methylmercury via ingestion of aquatic foods. OSPAR measures and subsequent EU measures regulate the main industrial sources for mercury releases to the environment. A suite of OSPAR measures control mercury emissions, discharges and sources. OSPAR has promoted actions in other international forums, especially the EU, e.g. call for actions to prevent pollution from the disposal of large amounts of pure and waste mercury arising from the closure or conversion of mercury cell chlor-alkali plants and for control measures on the use and marketing of mercury in various products.
    • A sensitive liquid chromatography/tandem mass spectrometry method for the determination of natural and synthetic steroid estrogens in seawater and marine biota, with a focus on proposed Water Framework Directive Environmental Quality Standards

      Ronan, J.; McHugh, B. (Wiley, 2013)
      RATIONALE: Trace levels of natural and synthetic steroid estrogens estrone (E1), 17b-estradiol (E2) and 17a-ethynyl estradiol (EE2) have been demonstrated to exert adverse effects in exposed organisms. E2 and EE2 have been proposed for inclusion in the Water Framework Directive (WFD) list of priority pollutants; however, the detection and accurate quantification of these compounds provide significant challenges, due to the low detection limits required. METHODS: A sensitive method combining ultrasonication, solid-phase extraction (SPE) and liquid chromatography/tandem mass spectrometry, with electrospray ionisation in negative mode (LC/ESI-MS/MS), capable of determining E1, E2 and EE2 at concentrations between 0.07 and 60 ng/L for seawater and between 0.4 and 200 ng/g wet weight in Mytilus spp. is reported. Recoveries at the limit of quantification (LOQ) ranged from 95 to 102% and 88 to 100% for water and tissue, respectively. Salinity (12 to 35%) and typical marine particulate matter loadings (between 10 and 100 mg/L) were not found to affect analyte recoveries. RESULTS: The first detection of E1 by LC/MS/MS in Irish marine waters (Dublin Bay, at 0.76 ng/L) is reported. Steroids were not detected in Galway Bay, or in any mussel samples from Dublin, Galway and Clare. The level of E2 detected in the dissolved water phase was below the proposed WFD Environmental Quality Standard (EQS) in other surface waters. CONCLUSIONS: The proposed method is suitable for the detection of E1, E2 and EE2 at biologically relevant concentrations and, due to the specificity offered, is not subject to potential interferences from endogenous E1 and E2 which often complicate the interpretation of estrogenic biomarker assays.
    • Stable isotope analysis of baleen reveals resource partitioning among sympatric rorquals and population structure in fin whales

      Ryan, C.; McHugh, B.; Trueman, C.N.; Sabin, R.; Deaville, R.; Harrod, C.; Berrow, S.D.; O'Connor, I. (Inter-Research, 2013)
      Stable isotope analysis is a useful tool for investigating diet, migrations and niche in ecological communities by tracing energy through food-webs. In this study, the stable isotopic composition of carbon and nitrogen in keratin was measured at growth increments of baleen plates from 3 sympatric species of rorquals (Balaenoptera acutrostrata, B. physalus and Megaptera novaeangliae), which died between 1985 and 2010 in Irish and contiguous waters. Bivariate ellipses were used to plot isotopic niches and standard ellipse area parameters were estimated via Bayesian inference using the SIBER routine in the SIAR package in R. Evidence of resource partitioning was thus found among fin, humpback and minke whales using isotopic niches. Highest δ15N values were found in minke whales followed by humpback, and fin whales. Comparison between Northeast Atlantic (Irish/UK and Biscayan) and Mediterranean fin whale isotopic niches support the current International Whaling Commission stock assessment of an isolated Mediterranean population. Significantly larger niche area and higher overall δ 15N and δ 13C values found in fin whales from Irish/UK waters compared to those sampled in adjacent regions (Bay of Biscay and Mediterranean) suggest inshore foraging that may be unique to fin whales in Ireland and the UK. Isotopic profiles support spatial overlap but different foraging strategies between fin whales sampled in Ireland/UK and the Bay of Biscay. Stable isotope analysis of baleen could provide an additional means for identifying ecological units, thus supporting more effective management for the conservation of baleen whales.
    • Survey of toxaphene concentrations in fish from European waters

      McHugh, B.; Nixon, E.; Klungsoyr, J.; Besselink, H.; Brouwer, A.; Rimkus, G.; Leonards, P.; de Boer, J. (2000)
      Toxaphene, a suspected carcinogen, is a broad spectrum chlorinated pesticide. The objective of this study was to provide information on the toxicological risks posed by toxaphene to the consumer of fish from European waters. The levels of 3 toxaphene congeners in various fish species from different geographical locations were determined. These data were then used to provide information on the exposure of toxaphene to the consumer of fish.
    • Toxicological risks to humans of toxaphene residues in fish

      Leonards, P.E.G.; Besselink, H.; Klungsøyr, J.; McHugh, B.; Nixon, E.; Rimkus, G.G.; Brouwer, A.; de Boer, J. (Wiley, 2011)
      A revised risk assessment for toxaphene was developed, based on the assumption that fish consumers are only exposed to toxaphene residues that differ substantially from technical toxaphene due to environmental degradation and metabolism. In vitro studies confirmed that both technical toxaphene and degraded toxaphene inhibit gap junctional intercellular communication that correlates with the mechanistic potential to cause tumour promotion. In vivo rat studies established the NOAEL for degraded and technical toxaphene at the highest dose tested in the bioassay. Toxaphene residue intakes from European fishery products were estimated and compared to the provisional tolerable daily intakes (TDIs) from various regulatory agencies including Canada, the United States, Germany. The estimated intake was also compared to a new calculated provisional MATT pTDI. The MATT pTDI is based upon new toxicological information (in vivo rat studies) developed on a model for environmental toxaphene residues rather than technical toxaphene. A MATT pTDI (1.08 mg total toxaphene for a person of 60 kg) for tumour promotion potency was adopted for use in Europe and is hitherto referred to as the MATT pTDI. These new data result in a better estimate of safety and a higher TDI than previously used. Based on realistic fish consumption data and recent baseline concentration data of toxaphene in European fishery products the toxaphene intake for the consumers of Germany, Ireland, Norway and The Netherlands was estimated. For an average adult fish consumer the average daily intake of toxaphene was estimated to be 1.2 µg, and 0.4, 0.5, and 0.2 µg for the consumers of Norway, Germany, Ireland, and The Netherlands, respectively. The toxaphene intake of these average fish consumers was far below the MATT pTDI of 1.08 mg/60 kg body weight. In conclusion, based on the most relevant toxicological studies and the most realistic estimates of fish consumption and recent concentrations of toxaphene in European fishery products, adverse health effects are unlikely for the average European consumer of fishery products. In no case is the MATT pTDI exceeded.
    • Utilising caging techniques to investigate metal assimilation in Nucella lapillus, Mytilus edulis and Crassostrea gigas at three Irish coastal locations

      Giltrap, M.; Macken, A.; Davoren, M.; McGovern, E.; Foley, B.; Larsen, M.; White, J.; McHugh, B. (Elsevier, 2013)
      Pollution by metals has been of increasing concern for a number of decades but at present, the mechanism of metal accumulation in sentinel species is not fully understood and further studies are required for environmental risk assessment of metals in aquatic environments. The use of caging techniques has proven to be useful for assessment of water quality in coastal and estuarine environments. This study investigates the application of caging techniques for monitoring uptake of 20 elements [Li, Na, Mg, Al, P, K, Ca, V, Cr, Mn, Fe, Ni, Co, Cu, As, Sb, Pb, Hg, Cd and Zn] in three marine species namely Nucella lapillus, Mytilus edulis and Crassostrea gigas. Stable isotopes were used to determine predatory effects and also used for modelling metal uptake in test species and to track nutrient assimilation. Metal levels were monitored at three different coastal locations, namely Dublin Bay, Dunmore East and Omey Island over 18 weeks. Significant differences in concentrations of Mn, Co and Zn between mussels and oysters were found. Correlations between cadmium levels in N. lapillus and δ13C and δ15N suggest dietary influences in Cd uptake. Levels of Zn were highest in C. gigas compared to the other two species and levels of Zn were most elevated at the Dunmore East site. Copper levels were more elevated in all test species at both Dublin Bay and Dunmore East. Mercury was raised in all species at Dunmore East compared to the other two sites. Biotic accumulation of metals in the test species demonstrates that caging techniques can provide a valid tool for biomonitoring in metal impacted areas.