Background The Food Safety Authority of Ireland (FSAI) in collaboration with the Department of Ag... more Background The Food Safety Authority of Ireland (FSAI) in collaboration with the Department of Agriculture, Fisheries and Food conducted a surveillance study on levels of chlorinated dioxins (PCDDs) and furans (PCDFs), brominated dioxins (PBDDs) and furans (PBDFs), polychlorinated biphenyls (PCBs), polybrominated biphenyls (PBBs), polybrominated diphenyl esters (PBDEs), hexabromocyclododecane enantiomers (HBCD Enantiomers), Decabromodiphenyl ethane, Hexabromobenzene, Bis(2,4,6-tribromophenoxy)ethane and Tetrabromo-bisphenol A (TBBP-A) in carcass fat, offal, eggs and milk produced in Ireland. This paper presents findings for PBDEs, PBBD/Fs and PBBs only and reflects increasing international awareness as to their potential persistent and bio-accumulating properties. Monitoring of these compounds was also recently recommended by the European Food Safety Authority 1. Very little occurrence data in food exists for PBDD/Fs and PBBs and this survey was conducted with a view to establish ba...
This paper presents a new model of voter behaviour under methods of proportional representation (... more This paper presents a new model of voter behaviour under methods of proportional representation (PR). We abstract away from rounding, and assume that a party securing k percent of the vote wins exactly k percent of the available seats. Under this assumption PR is not manipulable by any voter aiming at maximisation of the number of seats in the parliament
This research examined the effect of regular flooding upon PCDD/F and PCB levels in milk, beef an... more This research examined the effect of regular flooding upon PCDD/F and PCB levels in milk, beef and lamb, produced on the floodplains of industrial river catchments. Our unique dataset included more than 200 samples analysed for PCDD/Fs and PCBs over two data collection phases (1998-1999 & 2008-2010) from working farms. A robust paired study design was adopted with samples taken from flood-prone farms and nearby control farms not subject to flooding. On industrial river catchments regular flooding is associated with higher PCDD/F and PCB levels in soils and grass. This contamination may be transferred to food but the impact varied by food type. These contrasts may be due to physiological differences between animals, the ages at which they are sent to market and differences in animal husbandry. To minimise the risks of producing food on flood-prone land in industrial river catchments, as well as on any land with elevated PCDD/F and PCB levels, this research suggests a number of options. The choice of livestock may be important and as an example in our study beef cattle accumulated PCDD/Fs to a higher degree than sheep. Land management may also play a role and could include minimising the time that livestock spend on such land or feeding commercial feed, low in PCDD/Fs and PCBs, where appropriate.
The aryl hydrocarbon receptor (AhR) is required for the toxicity of 2,3,7,8-tetrachlorodibenzo-p-... more The aryl hydrocarbon receptor (AhR) is required for the toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), and so the AhR of CRL:WI and CRL:WI(Han) rats was characterized. Western blot showed AhR proteins of~110 and~97 kDa in individual rats from both strains. The AhR cDNA from a CRL:WI(Han) rat with thẽ 110-kDa protein revealed a sequence that was identical to that of the CRL:WI and SD rat. However, cloning of the AhR from a rat with the~97-kDa protein revealed a point mutation, and five variants encoding two C-terminally truncated variants of the AhR protein, arising from a point mutation in the intron/exon junction and consequent differential splicing. These C-terminally truncated variants were expressed and shown to give rise to a protein of~97 kDa; the recombinant AhR bound TCDD with an affinity that was not statistically different from the full-length protein. A single-nucleotide polymorphism assay was developed, and showed that both alleles were represented in a Hardy-Weinberg equilibrium in samples of CRL:WI and CRL:WI(Han) populations; both alleles are abundant. Rats from two studies of TCDD developmental toxicity were genotyped, and the association with toxicity investigated using statistical analysis. There was no plausible evidence that the AhR allele had a significant effect on the toxic endpoints examined. These data show that the two AhR alleles are common in two strains of Wistar rat, and that the AhR alleles had no effect on TCDD-induced developmental toxicity in two independent studies.
We extend the Gibbard-Satterthwaite theorem in the following way. We prove that an onto, non-dict... more We extend the Gibbard-Satterthwaite theorem in the following way. We prove that an onto, non-dictatorial social choice rule which is employed to choose one of at least three alternatives is safely manipulable. This means that on occasion a voter will have an incentive to make a strategic vote and know that he will not be worse off regardless of how other voters with similar preference orders would vote, sincerely or not.
The most commonly consumed shellfish species produced in Scotland - mussels, oysters and scallops... more The most commonly consumed shellfish species produced in Scotland - mussels, oysters and scallops - were investigated for the occurrence of a range of brominated and chlorinated contaminants in order to establish current levels and estimate human dietary exposure. Flesh from individual sub-samples was representatively pooled and 35 composites were analysed for brominated and chlorinated dioxins (PBDD/Fs, PCDD/Fs), brominated and chlorinated biphenyls (PBBs, PCBs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs) and tetrabromobisphenol A (TBBPA). The analytical methodology used (13)C(12) labelled surrogates of the target compounds, with GC coupled to (usually) high resolution MS, and LC-MS/MS for HBCD and TBBPA analysis. Positive identifications were made in the majority of samples for most analytes with the exception of TBBPA and most PBDD congeners measured. None of the levels detected for PCDD/F and PCB were above the maximum permitted levels specified in European Union regulations. The levels of brominated furans predominated over brominated dioxins, reflecting the environmental distribution and source emission profiles of these contaminants, and relatively high levels of the tri-brominated congeners were observed. Levels of the flame retardant chemicals reflected current and legacy use, with appreciable concentrations of PBDEs and HBCDs (predominantly alpha-HBCD) but far lower levels of PBBs. TBBPA was not detected in any of the species. In general, mussels and oysters displayed relatively higher levels of contamination than scallops, although the gonad tissue of the latter showed significant levels of brominated dioxins. The estimated adult dietary intakes of PCDD/Fs and PCBs arising from the consumption of a typical portion of these foods in combination with an otherwise average UK diet were in the range 0.5-0.6 pg World Health Organisation (WHO)-toxic equivalent (TEQ)(2005)/kg bodyweight per day. These estimated dietary intakes are well within the Tolerable Daily Intake for dioxins and dioxin-like PCBs of 2 pg WHO-TEQ(2005)/kg bodyweight/day endorsed by the independent expert Committee on Toxicology of Chemicals in Food, Consumer Products and the Environment. The corresponding intakes for sumPBDEs and sumHBCDs were 5.6-6.1 and 5.9-7.9 ng/kg bodyweight/day respectively.
The goal of this paper is to examine the incentives to vote insincerely, other than those created... more The goal of this paper is to examine the incentives to vote insincerely, other than those created by rounding, faced by voters in systems of proportional representation (PR). We rigorously investigate two models of voter behaviour. The first model assumes that a voter is primarily interested in the distribution of seats in the post-election parliament (seat maximizer) while the second considers a voter who is concerned with the distribution of power in it (power maximizer). We show that under pure PR, seat maximizers do not have any incentives to manipulate, which justifies the Bowler and Lanoue (1992) claim, and that such incentives for seat maximizers appear with the introduction of a threshold. We show that, even in the absence of a threshold, there will always exist circumstances where a power maximizer would have an incentive to vote insincerely. We demonstrate that her incentives to make an insincere vote depend on her attitude towards uncertainty. The introduction of a thresh...
To control the outbreak of foot and mouth disease, which occurred in the UK in early 2001, a larg... more To control the outbreak of foot and mouth disease, which occurred in the UK in early 2001, a large number of farm animals were slaughtered. Where it was not possible to render or landfill the carcasses, they were destroyed by burning on open pyres, with wood, coal and other materials. Uncontrolled combustion such as this is known to produce small quantities of dioxins and an investigation was made into whether, as a result of the burning, there was an elevation in the concentrations of these compounds in food produced in the areas close to the pyres. With few exceptions, concentrations of PCDD/Fs and PCBs were within the expected ranges as predicted by reference data. No accumulation over time was evident from a repeat milk sampling exercise. Where elevated concentrations of PCDD/Fs and PCBs were found in chickens and eggs, they were in samples not destined for the food chain. Elevated levels in some samples of milk from Dumfries and Galloway were not found in earlier or later samples and may have been found as a result of a temporary feeding regime. Elevated concentrations in lamb from Carmarthenshire were from very young animals which would not have entered the food chain. There was no evidence of any significant increase in dietary exposure to PCDD/Fs and PCBs as a result of the FMD pyres.
An extraction method for the quantitative analysis of polybrominated diphenyl ethers (PBDEs) in a... more An extraction method for the quantitative analysis of polybrominated diphenyl ethers (PBDEs) in aqueous samples has been evaluated. The analytical methodology includes the sample filtration through glass fiber filter and subsequent extraction of dissolved phase compounds by C18 solid-phase disk extraction. Dependence of extraction efficiency on factors such as pollutant concentrations, sample volume, and stability during storage has been investigated. Mean extraction efficiencies of 97% for total PBDEs (13 trito heptabrominated congeners at spiking levels in the range of 15-90 pg) with a RSD between 9 and 20% were achieved. Higher recoveries were observed for the more volatile PBDEs (112%) in relation to more brominated congeners (88%). The developed methodology was successfully applied to the analysis of these compounds in atmospheric deposition and snow samples from remote sites in Europe with method detection and quantitation limits in the range of 2.1-10 pg L −1 for almost all congeners, which allow the determination of PBDEs in remote areas with levels in the range of low to medium pg L −1 for PBDEs.
Page 1. Food & Agricultural Immunology (1994) 6, 17-22 Comparison of ELISA and HPLC Technique... more Page 1. Food & Agricultural Immunology (1994) 6, 17-22 Comparison of ELISA and HPLC Techniques for the Analysis of Carbendazim and Thiabendazole Residues in Fruit and Vegetables KATRINA A. MOUNTFORT, STEWART ...
Background The Food Safety Authority of Ireland (FSAI) in collaboration with the Department of Ag... more Background The Food Safety Authority of Ireland (FSAI) in collaboration with the Department of Agriculture, Fisheries and Food conducted a surveillance study on levels of chlorinated dioxins (PCDDs) and furans (PCDFs), brominated dioxins (PBDDs) and furans (PBDFs), polychlorinated biphenyls (PCBs), polybrominated biphenyls (PBBs), polybrominated diphenyl esters (PBDEs), hexabromocyclododecane enantiomers (HBCD Enantiomers), Decabromodiphenyl ethane, Hexabromobenzene, Bis(2,4,6-tribromophenoxy)ethane and Tetrabromo-bisphenol A (TBBP-A) in carcass fat, offal, eggs and milk produced in Ireland. This paper presents findings for PBDEs, PBBD/Fs and PBBs only and reflects increasing international awareness as to their potential persistent and bio-accumulating properties. Monitoring of these compounds was also recently recommended by the European Food Safety Authority 1. Very little occurrence data in food exists for PBDD/Fs and PBBs and this survey was conducted with a view to establish ba...
This paper presents a new model of voter behaviour under methods of proportional representation (... more This paper presents a new model of voter behaviour under methods of proportional representation (PR). We abstract away from rounding, and assume that a party securing k percent of the vote wins exactly k percent of the available seats. Under this assumption PR is not manipulable by any voter aiming at maximisation of the number of seats in the parliament
This research examined the effect of regular flooding upon PCDD/F and PCB levels in milk, beef an... more This research examined the effect of regular flooding upon PCDD/F and PCB levels in milk, beef and lamb, produced on the floodplains of industrial river catchments. Our unique dataset included more than 200 samples analysed for PCDD/Fs and PCBs over two data collection phases (1998-1999 & 2008-2010) from working farms. A robust paired study design was adopted with samples taken from flood-prone farms and nearby control farms not subject to flooding. On industrial river catchments regular flooding is associated with higher PCDD/F and PCB levels in soils and grass. This contamination may be transferred to food but the impact varied by food type. These contrasts may be due to physiological differences between animals, the ages at which they are sent to market and differences in animal husbandry. To minimise the risks of producing food on flood-prone land in industrial river catchments, as well as on any land with elevated PCDD/F and PCB levels, this research suggests a number of options. The choice of livestock may be important and as an example in our study beef cattle accumulated PCDD/Fs to a higher degree than sheep. Land management may also play a role and could include minimising the time that livestock spend on such land or feeding commercial feed, low in PCDD/Fs and PCBs, where appropriate.
The aryl hydrocarbon receptor (AhR) is required for the toxicity of 2,3,7,8-tetrachlorodibenzo-p-... more The aryl hydrocarbon receptor (AhR) is required for the toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), and so the AhR of CRL:WI and CRL:WI(Han) rats was characterized. Western blot showed AhR proteins of~110 and~97 kDa in individual rats from both strains. The AhR cDNA from a CRL:WI(Han) rat with thẽ 110-kDa protein revealed a sequence that was identical to that of the CRL:WI and SD rat. However, cloning of the AhR from a rat with the~97-kDa protein revealed a point mutation, and five variants encoding two C-terminally truncated variants of the AhR protein, arising from a point mutation in the intron/exon junction and consequent differential splicing. These C-terminally truncated variants were expressed and shown to give rise to a protein of~97 kDa; the recombinant AhR bound TCDD with an affinity that was not statistically different from the full-length protein. A single-nucleotide polymorphism assay was developed, and showed that both alleles were represented in a Hardy-Weinberg equilibrium in samples of CRL:WI and CRL:WI(Han) populations; both alleles are abundant. Rats from two studies of TCDD developmental toxicity were genotyped, and the association with toxicity investigated using statistical analysis. There was no plausible evidence that the AhR allele had a significant effect on the toxic endpoints examined. These data show that the two AhR alleles are common in two strains of Wistar rat, and that the AhR alleles had no effect on TCDD-induced developmental toxicity in two independent studies.
We extend the Gibbard-Satterthwaite theorem in the following way. We prove that an onto, non-dict... more We extend the Gibbard-Satterthwaite theorem in the following way. We prove that an onto, non-dictatorial social choice rule which is employed to choose one of at least three alternatives is safely manipulable. This means that on occasion a voter will have an incentive to make a strategic vote and know that he will not be worse off regardless of how other voters with similar preference orders would vote, sincerely or not.
The most commonly consumed shellfish species produced in Scotland - mussels, oysters and scallops... more The most commonly consumed shellfish species produced in Scotland - mussels, oysters and scallops - were investigated for the occurrence of a range of brominated and chlorinated contaminants in order to establish current levels and estimate human dietary exposure. Flesh from individual sub-samples was representatively pooled and 35 composites were analysed for brominated and chlorinated dioxins (PBDD/Fs, PCDD/Fs), brominated and chlorinated biphenyls (PBBs, PCBs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs) and tetrabromobisphenol A (TBBPA). The analytical methodology used (13)C(12) labelled surrogates of the target compounds, with GC coupled to (usually) high resolution MS, and LC-MS/MS for HBCD and TBBPA analysis. Positive identifications were made in the majority of samples for most analytes with the exception of TBBPA and most PBDD congeners measured. None of the levels detected for PCDD/F and PCB were above the maximum permitted levels specified in European Union regulations. The levels of brominated furans predominated over brominated dioxins, reflecting the environmental distribution and source emission profiles of these contaminants, and relatively high levels of the tri-brominated congeners were observed. Levels of the flame retardant chemicals reflected current and legacy use, with appreciable concentrations of PBDEs and HBCDs (predominantly alpha-HBCD) but far lower levels of PBBs. TBBPA was not detected in any of the species. In general, mussels and oysters displayed relatively higher levels of contamination than scallops, although the gonad tissue of the latter showed significant levels of brominated dioxins. The estimated adult dietary intakes of PCDD/Fs and PCBs arising from the consumption of a typical portion of these foods in combination with an otherwise average UK diet were in the range 0.5-0.6 pg World Health Organisation (WHO)-toxic equivalent (TEQ)(2005)/kg bodyweight per day. These estimated dietary intakes are well within the Tolerable Daily Intake for dioxins and dioxin-like PCBs of 2 pg WHO-TEQ(2005)/kg bodyweight/day endorsed by the independent expert Committee on Toxicology of Chemicals in Food, Consumer Products and the Environment. The corresponding intakes for sumPBDEs and sumHBCDs were 5.6-6.1 and 5.9-7.9 ng/kg bodyweight/day respectively.
The goal of this paper is to examine the incentives to vote insincerely, other than those created... more The goal of this paper is to examine the incentives to vote insincerely, other than those created by rounding, faced by voters in systems of proportional representation (PR). We rigorously investigate two models of voter behaviour. The first model assumes that a voter is primarily interested in the distribution of seats in the post-election parliament (seat maximizer) while the second considers a voter who is concerned with the distribution of power in it (power maximizer). We show that under pure PR, seat maximizers do not have any incentives to manipulate, which justifies the Bowler and Lanoue (1992) claim, and that such incentives for seat maximizers appear with the introduction of a threshold. We show that, even in the absence of a threshold, there will always exist circumstances where a power maximizer would have an incentive to vote insincerely. We demonstrate that her incentives to make an insincere vote depend on her attitude towards uncertainty. The introduction of a thresh...
To control the outbreak of foot and mouth disease, which occurred in the UK in early 2001, a larg... more To control the outbreak of foot and mouth disease, which occurred in the UK in early 2001, a large number of farm animals were slaughtered. Where it was not possible to render or landfill the carcasses, they were destroyed by burning on open pyres, with wood, coal and other materials. Uncontrolled combustion such as this is known to produce small quantities of dioxins and an investigation was made into whether, as a result of the burning, there was an elevation in the concentrations of these compounds in food produced in the areas close to the pyres. With few exceptions, concentrations of PCDD/Fs and PCBs were within the expected ranges as predicted by reference data. No accumulation over time was evident from a repeat milk sampling exercise. Where elevated concentrations of PCDD/Fs and PCBs were found in chickens and eggs, they were in samples not destined for the food chain. Elevated levels in some samples of milk from Dumfries and Galloway were not found in earlier or later samples and may have been found as a result of a temporary feeding regime. Elevated concentrations in lamb from Carmarthenshire were from very young animals which would not have entered the food chain. There was no evidence of any significant increase in dietary exposure to PCDD/Fs and PCBs as a result of the FMD pyres.
An extraction method for the quantitative analysis of polybrominated diphenyl ethers (PBDEs) in a... more An extraction method for the quantitative analysis of polybrominated diphenyl ethers (PBDEs) in aqueous samples has been evaluated. The analytical methodology includes the sample filtration through glass fiber filter and subsequent extraction of dissolved phase compounds by C18 solid-phase disk extraction. Dependence of extraction efficiency on factors such as pollutant concentrations, sample volume, and stability during storage has been investigated. Mean extraction efficiencies of 97% for total PBDEs (13 trito heptabrominated congeners at spiking levels in the range of 15-90 pg) with a RSD between 9 and 20% were achieved. Higher recoveries were observed for the more volatile PBDEs (112%) in relation to more brominated congeners (88%). The developed methodology was successfully applied to the analysis of these compounds in atmospheric deposition and snow samples from remote sites in Europe with method detection and quantitation limits in the range of 2.1-10 pg L −1 for almost all congeners, which allow the determination of PBDEs in remote areas with levels in the range of low to medium pg L −1 for PBDEs.
Page 1. Food & Agricultural Immunology (1994) 6, 17-22 Comparison of ELISA and HPLC Technique... more Page 1. Food & Agricultural Immunology (1994) 6, 17-22 Comparison of ELISA and HPLC Techniques for the Analysis of Carbendazim and Thiabendazole Residues in Fruit and Vegetables KATRINA A. MOUNTFORT, STEWART ...
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