• Determination and Occurrence of Phenoxyacetic Acid Herbicides and Their Transformation Products in Groundwater Using Ultra High Performance Liquid Chromatography Coupled to Tandem Mass Spectrometry

      McManus, Sarah-Louise; Moloney, Mary; Richards, Karl G.; Coxon, Catherine E.; Danaher, Martin (MDPI AG., Basel, Switzerland, 10/12/2014)
      A sensitive method was developed and validated for ten phenoxyacetic acid herbicides, six of their main transformation products (TPs) and two benzonitrile TPs in groundwater. The parent compounds mecoprop, mecoprop-p, 2,4-D, dicamba, MCPA, triclopyr, fluroxypr, bromoxynil, bentazone, and 2,3,6-trichlorobenzoic acid (TBA) are included and a selection of their main TPs: phenoxyacetic acid (PAC), 2,4,5-trichloro-phenol (TCP), 4-chloro-2-methylphenol (4C2MP), 2,4-dichlorophenol (DCP), 3,5,6-trichloro-2-pyridinol (T2P), and 3,5-dibromo-4-hydroxybenzoic acid (BrAC), as well as the dichlobenil TPs 2,6-dichlorobenzamide (BAM) and 3,5-dichlorobenzoic acid (DBA) which have never before been determined in Irish groundwater. Water samples were analysed using an efficient ultra-high performance liquid chromatography (UHPLC) method in an 11.9 min separation time prior to detection by tandem mass spectrometry (MS/MS). The limit of detection (LOD) of the method ranged between 0.00008 and 0.0047 µg·L−1 for the 18 analytes. All compounds could be detected below the permitted limits of 0.1 µg·L−1 allowed in the European Union (EU) drinking water legislation [1]. The method was validated according to EU protocols laid out in SANCO/10232/2006 with recoveries ranging between 71% and 118% at the spiked concentration level of 0.06 µg·L−1. The method was successfully applied to 42 groundwater samples collected across several locations in Ireland in March 2012 to reveal that the TPs PAC and 4C2MP were detected just as often as their parent active ingredients (a.i.) in groundwater.
    • Control and detection of food-borne pathogens

      Duffy, Geraldine; Cloak, Orla; Sheridan, James J. (Teagasc, Ballsbridge, Dublin 4, 1998-08)
      The objective of this study was to develop rapid methods for the detection of bacteria from food.
    • The microbiological safety and quality of foods processed by the "sous vide" system as a method of commercial catering

      Bolton, Declan J. (Teagasc, Ballsbridge, Dublin 4, 1998-08)
      The objective of this project was to improve the quality and safety of sous vide foods by investigating the responses of the food-poisoning microorganisms to the processing and storage conditions used in this technology. The major food poisoning bacteria of concern in sous vide foods are strains of Clostridium botulinum, Bacillus cereus, verotoxigenic Escherichia coli O157:H7 (VTEC), Salmonella spp., Listeria monocytogenes and Yersinia enterocolitica.
    • Escherichia coli 0157:H7: implications for HACCP on the farm and in the abattoir

      Bolton, Declan J.; Byrne, Catriona; Sheridan, James J.; Riordan, Denise C. (Teagasc, 1999-01)
      Experiments were designed to assess the risks associated with Escherichia coli O157:H7 on the farm, through the abattoir and into the butcher shop. Data was also generated for application in model building and the reliability of pathogen models for predicting pathogen growth in different foods was examined.
    • Development of HACCP analysis systems for beef slaughter

      Doherty, Alice M.; McEvoy, John M.; Sheridan, James J.; McGuire, Liam; O'Sullivan, Marian (Teagasc, Ballsbridge, Dublin 4, 1999-01)
      The aim of this study was to establish the types and levels of bacterial contamination on beef carcasses slaughtered under commercial conditions. This information is necessary as baseline data for the implementation of a Hazard Analysis Critical Control Point (HACCP) plan in a meat factory. Samples were taken over a twelve month period from five carcass sites representing the fore and hind quarters of the carcass. These included the hock, bung, inside round, cranial back and brisket. The carcasses were sampled at different stages of dressing namely legging, hide removal, evisceration, carcass splitting, carcass washing and chilling (24 h later). Four meat cuts (inside round, outside round, chuck roll (cranial back) and brisket) were also sampled after boning. Counts were enumerated for the following groups of bacteria: total bacterial counts (25°C and 4°C); pseudomonad counts (25°C and 4°C); E nterobacteriaceae counts; E scherichia coli O157:H7 and L isteria spp.
    • Methods for veterinary drug residue analysis in food

      O'Keeffe, Michael (Teagasc, 1999-02)
      A comprehensive capability to test for residues of veterinary drugs is an important support for the Irish food industry. There is a requirement for food manufacturers to demonstrate the compliance of their products with stringent customer specifications. In addition, legislative requirements are becoming more exacting both in terms of the range of substances covered and the lower residue levels to which test systems must measure.
    • Protein-bound veterinary drug residues in food

      O'Keeffe, Michael; Horne, Elizabeth; Cadogan, Aodhmar; Coyle, Tiernan (Teagasc, 1999-03)
      Bound residues of veterinary drugs have been recognised as an important aspect of food safety particularly (a) where such residues may persist for long periods after withdrawal of the drug treatment and (b) where the bound residues may be released, during digestion of edible tissues, in biologically active forms. Residues bound to proteins are not extractable by the conventional solvent extraction procedures for residue determination. Procedures for the release of bound residues from proteins, identification of their chemical structure, and determination of the amount of bound residues in edible tissues are required.
    • Supercritical fluid extraction of veterinary drug residues from meat

      O'Keeffe, Mandy J.; O'Keeffe, Michael (Teagasc, 1999-10)
      Extraction is a key step in the analysis of food samples for residues of veterinary drugs. Over the last ten years there has been increasing interest in alternatives to the use of organic solvents for sample extraction. The development of supercritical fluid extraction (SFE) for the determination of residues in meat provides alternative methods, which may be automated and which have attractive properties such as avoidance of organic solvents and increased speed of extraction. This project is a jointly-funded United States Department of Agriculture and Department of Agriculture and Food activity with the objective of developing robust SFE procedures suitable for the quantitative recovery of ß-agonists (illegal growth promoters) from animal tissue. Fundamental aspects of SFE in its application to residue analysis are also addressed.
    • Development of a critical control step for E.coli 0157:H7 in pepperoni

      Duffy, Geraldine; Riordan, Denise C.; Sheridan, James J. (Teagasc, 1999-10)
      Verocytotoxin producing Escherichia coli (VTEC) and particularly strains of serogroup O157, have emerged as food poisoning pathogens which can cause a severe and potentially fatal illness. The symptoms of VTEC infection include haemorrhagic colitis with bloody diarrhoea and severe abdominal pain. The infection may lead to renal failure as a result of haemolytic uraemic syndrome. Because of the severity of the illness and the low infectious dose, this pathogen is classed as a serious food safety issue. It is recommended by the United States Department of Agriculture that the production process for ready to eat foods such as fermented meats (pepperoni, salami etc.) should be capable of addressing a worst case scenario ie. the production process should be able to yield a log105.0cfu /g (105 cfu/g) reduction in numbers of E. coli O157:H7 on the raw meat. The aim of this study was to develop an industrially viable critical control step(s) which could be implemented into the pepperoni production process.
    • The survival of added escherichia coli O157:H7 in natural mineral water and its products and the development of a rapid method for enumeration of the heterotrophic bacteria in natural mineral water

      Kerr, Marie; Fitzgerald, Margaret; Sheridan, James J. (Teagasc, 2000-12)
      The consumption of natural mineral water is rapidly growing and outpacing all other beverages on a global scale. In Europe, bottled water already has a bigger market share than carbonated soft drinks. Yet there is only a limited availability of information on the microbiological safety and quality of bottled natural mineral waters sold within the European Community. As natural mineral water does not receive any bacteriocidal treatment prior to bottling, the risk of pathogen contamination is a public health concern. Pathogen contamination may occur as a result of over exploitation of natural mineral water resources i.e. over abstraction by commercial bottling companies may lead to disturbance of the water table causing contaminated surface water to be drawn down into ground water supplies (Green and Green 1994). Such contamination was implicated in an outbreak of cholera associated with the consumption of bottled natural mineral water in Portugal in 1974 (Blake et al. 1977). The transport and dissemination of E. coli and enterococci in a limestone aquifer had been demonstrated by Personné et al. (1998), confirmation that E. coli can survive the transitory period from the surface to underground water supplies, thus raising the question of E. coli O157:H7 with its low infective dose < 10 cells (Willshaw et al. 1994 and Tilden et al. 1996) surviving the transitory period from surface to a natural mineral water aquifer.
    • Routine diagnostic tests for food-borne pathogens

      Duffy, Geraldine; Kilbride, Brendan; Fitzmaurice, Justine; Sheridan, James J. (Teagasc, 2001-01)
      Rapid techniques were developed and applied to the determination of total viable bacteria and to the detection of food borne pathogens (Listeria monocytogenes, Salmonella, Campylobacter jejuni and E. coli O157:H7). The method developed for total viable counts is based on membrane filtration and fluorescent staining and the technique can be performed and a result obtained within 20 min. The results correlate well with the standard plate count and the technique is now being implemented in Irish food factories.
    • Methods for antibiotic residues in food

      O'Keeffe, Mandy J.; Walshe, Michaela; Horne, Elizabeth; O'Keeffe, Michael; Foran, Shane; Lardner, Caroline; Daly, Tracy; Kane, Marian (Teagasc, 2001-04)
      A comprehensive capability to test for residues of veterinary drugs is an important support for the Irish food industry. There is a requirement for food manufacturers to demonstrate the compliance of their products with stringent customer specifications. In addition, legislative requirements are becoming more exacting both in terms of the range of substances covered and the lower residue levels to which test systems must measure.
    • Control of escherichia coli 0157:H7 in beefburgers

      Bolton, Declan J.; Byrne, Catriona; Catarame, Terese; Sheridan, James J. (Teagasc, 2001-04)
      The inactivation of E. coli O157:H7 by heating, freezing, pulsed electric field, sodium lactate, lactic acid and citric acid, alone or in combination was investigated. The industrial process for beefburger manufacture did not significantly reduce E.coli O157:H7 numbers regardless of the burger recipe and method of tempering used. Fast freezing of the burgers (to -18°C in 30 minutes as opposed to 36 hours), pulsed electric field, sodium lactate, lactic acid and citric acid, individually and in combination, did not significantly reduce E. coli O157:H7 numbers when applied at different stages throughout the beef burger manufacturing process. Beefburger safety is therefore reliant on proper storage, handling and thermal processing in the domestic or catering kitchen. The lethal effect of thermal processing may be enhanced by the addition of sodium lactate to the burger during mixing. These results are presented and discussed.
    • Food residue database

      O'Keeffe, Michael; Kennedy, Orla; Farrell, Frank; Nolan, Marie-Louise; Dooley, Martin; Byrne, Patrick; Nugent, Audrey; Cantwell, Helen; Horne, Elizabeth; Nelson, Victor; McGrath, David (Teagasc, 2001-11)
      The Food Residue Database contains a broad range of residue studies in foods of animal origin for the period 1995 to 2000, covering veterinary drugs, pesticides and contaminants. In most cases, such as antiparasitic drugs, beta-agonists, pesticides, dioxins, mycotoxins, heavy metals and polycyclic aromatic hydrocarbons, the picture for Irish dairy, meat and fish products is good with residue levels being low or non-measurable. In a few cases, such as ivermectin in farmed salmon and tetracycline residues in pork, improvements in the situation were observed with subsequent studies. Antimicrobial residues, in general, are not a problem but levels above MRL values have been found indicating the need for good practice in use of veterinary medicines. A problem with elevated nitrate levels in dairy powders may be resolved by the industry through observance of good manufacturing practices. Summary Reports on all the studies carried out for the Food Residue Database are available to food companies and other interested parties.
    • A European study on animal food & biomedical aspects of E.coli 0157:H7

      Duffy, Geraldine; Garvey, Patricia; Sheridan, James J. (Teagasc, 2002-02)
      Verocytotoxin producing Escherichia coli (VTEC) and, in particular, strains of serogroup O157, have emerged as significant pathogens causing a range of severe and potentially fatal illnesses. The European Union has recognised the threat posed by E coli O157:H7 and the need to devise control strategies based on an understanding of VTEC pathogenicity, transmission, survival and growth. It acknowledges the importance of informing farmers, veterinarians, food producers and health authorities so that each of these groups can act appropriately to reduce the overall hazards posed by these organisms. To contribute to the development and dissemination of effective control strategies, the European Commission funded this Concerted Action Project 1
    • HACCP for Irish beef, pork and lamb slaughter

      Bolton, Declan J.; Sheridan, James J. (Teagasc, 2002-02)
      It is generally accepted that HACCP principles should be incorporated into the food safety control systems in meat processing plants to better assure food safety. The objective of this project was to publish detailed HACCP slaughter documents for the Irish beef, pork and lamb processing industries. These would provide the necessary information and detail to facilitate the implementation of HACCP on the slaughter floor (from lairage to chilling) in Irish meat plants. To this end `HACCP for Irish Beef Slaughter' was published in October 2000, `HACCP for Irish Pork Slaughter' in December 2001 and `HACCP for Irish Lamb Slaughter' will be available early in 2002. These are non-generic, detailed documents which provide the scientific basis for establishing critical control points (CCP), critical limits, monitoring and corrective action procedures.
    • Spread of brain and spinal cord material during beef slaughter

      Daly, Dyan J.; Prendergast, Deirdre M.; Sheridan, James J. (Teagasc, 2002-04)
      Emboli of brain tissue in the lungs have been reported in cases following severe head injury (McMillan 1956) and birth trauma in people (Hauck e t al 1990) and in cattle following stunning (Bauer 1996; Garland 1996). This has important implications for food safety if the brain tissue of stunned cattle is infected with the prion responsible for bovine spongiform encephalopathy (BSE), (Prusiner 1991). BSE emerged following changes in the rendering process in the early 1980s which allowed the aetiologic agent to survive, contaminate protein feed supplement and infect cattle (Brown e t al. 2001). Within a short period of time after the first case of BSE, concerns were expressed regarding the transmission of BSE to humans and the likelihood of infection from consumption of beef and beef products. This has become increasingly significant with the discovery of the link between BSE in cattle and variant Creutzfeldt-Jakob disease (vCJD) in man (Bruce e t al 1997).
    • Risk-based determination of critical control points for pork slaughter

      Bolton, Declan J.; Pearce, Rachel; Sheridan, James J. (Teagasc, 2002-05)
      To identify the critical control points (CCPs) during commercial pork slaughter, 60 pigs in a small abattoir (80 pigs per day) and a similar number in a larger plant (2000 pigs per day) and/or their resultant carcasses were swabbed at the ham, belly and neck. The total bacterial contamination was determined after each stage from the live pigs on the farm to chilling of the carcasses in the abattoir.
    • Rapid control systems for veterinary drug residues in food producing animals

      O'Keeffe, Michael (Teagasc, 2002-10)
      The aim was to develop rapid systems which could be used to test for the presence of veterinary drug residues in food producing animals. Body fluid samples are most suitable for rapid testing systems so as to avoid the lengthy residue extraction procedures required for tissue samples. Urine was analysed for sulphamethazine, a licensed antimicrobial, and for chlorotestosterone, a prohibited growth promoting agent, as models to demonstrate the different approaches.
    • Hygiene and safety of Irish beef carcasses.

      Kerr, Marie; Sheridan, James J. (Teagasc, 2002-10)
      Investigations were carried out in a number of beef abattoirs in Ireland. Information was obtained on the hygienic status of the carcasses being produced and also on their safety, using the presence of Salmonella as an indicator. The data showed that, in general, the hygiene of the carcasses being produced was of a satisfactory quality and that faecal contamination was low, as indicated by the coliform and E. coli counts. The safety of the carcasses as indicated by the presence of Salmonella was considered to be a cause for concern. The level of contamination by this pathogen of 7.6% was considered to be high and requires investigation. The majority of the Salmonella present on carcasses was S. typhimurium DT104, which is resistant to a range of antibodies. The work was part of an EU project and some results are presented from other partners.