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Kevin V. Thomas - One of the best experts on this subject based on the ideXlab platform.
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Antifouling paint booster Biocides in UK coastal waters: Inputs, occurrence and environmental fate
Science of the Total Environment, 2002Co-Authors: Kevin V. Thomas, Mathew McHugh, Mike WaldockAbstract:This study considered the inputs of antifouling paint booster Biocides into the aquatic environment directly from painted hulls and high pressure hosing operations, the occurrence of booster Biocides in marinas, harbours and docks, and the influence of degradation and water-sediment partition on their environmental fate. Irgarol 1051, the Irgarol 1051 degradation product GS26575, diuron, and the diuron degradation products 1-(3-chlorophenyl)-3,1-dimethylurea (CPDU), 1-(3,4-dichlorophenyl)-3-methylurea (DCPMU) and 1-(3,4-dichlorophenyl)urea (DCPU) were all detected at measurable concentrations in surface waters. Irgarol 1051, GS26575 and diuron were also detected in bottom sediments. A preliminary study of Biocide input during both normal use and foreshore hull hosing showed that hosing may be a significant point source input and also be a cause for future concern since much of this input is in the form of paint particles. Field based measurements and laboratory experiments showed that Irgarol 1051 and diuron persist in the water column, due to a low affinity to partition onto sedimentary material and high resistance to degradation. Other Biocides such as chlorothalonil, dichlofluanid, and Sea-Nine 211 were all found to be rapidly removed from the water column and be less persistent. Copyright ?? 2002 Elsevier Science B.V.
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The environmental fate and behaviour of antifouling paint booster Biocides: A review
Biofouling, 2001Co-Authors: Kevin V. ThomasAbstract:Antifouling paint booster Biocides are a group of organic compounds added to antifouling paints to improve their efficacy. They have become prevalent since the requirement for alternative antifouling paints formulations for small boats (< 25 m). This need followed a ban on the use of triorganotin Biocides in antifouling paints for small boats, in the late 1980's. Worldwide, around eighteen compounds are currently used as antifouling Biocides, viz. benzmethylamide, chlorothalonil, copper pyrithione, dichlofluanid, diuron, fluorofolpet, Irgarol 1051, Sea‐Nine 211, Mancozeb, Polyphase, pyridine‐triphenyl‐borane, TCMS (2,3,5,6‐tetrachloro‐4‐methylsulfonyl) pyridine, TCMTB [2‐(thiocyanomethylthio)benzothia‐zole], Thiram, tolyfluanid, zinc pyrithione (ZPT), ziram and Zineb. Any booster Biocide released into the environment is subjected to a complex set of processes. These processes include transport mechanisms, transformation, degradation, cross media partitioning, and bioaccumulation. This paper reviews the fa...
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Antifouling Paint Booster Biocide Contamination in UK Marine Sediments
Marine Pollution Bulletin, 2000Co-Authors: Kevin V. Thomas, S.j Blake, M. J. WaldockAbstract:The proposed International Maritime Organization (IMO) ban on tributyltin (TBT) as an antifouling paint Biocide, will raise the inevitability of the increased use of alternative paints containing copper and organic booster Biocides. Although the fate of TBT in marine sediments has been extensively studied, very little work has been performed to assess the accumulation of organic booster Biocides in sediments. A survey was conducted to determine concentrations of TBT, Irgarol 1051, the Irgarol 1051 metabolite GS26575 (2-(tert-butylamino)-4-amino-6-(methylthio)-1,3,5-triazine; also referred to as M1) and diuron in coastal and off-shore sediments. TBT was consistently determined at the highest concentrations and was detected in all sediments collected from Southampton Water, UK, along with the TBT degradation product dibutyltin (DBT). Irgarol 1051 was detected (0.01–0.11 μg/g) in some sediments collected from marinas, where high concentrations of these compounds have been measured in surface waters. The Irgarol 1051 metabolite 2-methylthio-4-tert-butylamino-6-amino-s-triazine (M1/GS26575) was only detected at a few locations at concentrations
Jose L Martinez - One of the best experts on this subject based on the ideXlab platform.
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multiple adaptive routes of salmonella enterica typhimurium to Biocide and antibiotic exposure
BMC Genomics, 2016Co-Authors: Tânia Curiao, Emmanuela Marchi, Denis Grandgirard, Ricardo Leonsampedro, Carlo Viti, Stephen L Leib, Fernando Baquero, Marco R Oggioni, Jose L MartinezAbstract:Biocides and antibiotics are used to eradicate or prevent the growth of microbial species on surfaces (occasionally on catheters), or infected sites, either in combination or sequentially, raising concerns about the development of co-resistance to both antimicrobial types. The effect of such compounds on Salmonella enterica, a major food-borne and zoonotic pathogen, has been analysed in different studies, but only few works evaluated its biological cost, and the overall effects at the genomic and transcriptomic levels associated with diverse phenotypes resulting from Biocide exposure, which was the aim of this work. Exposure to triclosan, clorhexidine, benzalkonium, (but not to hypochlorite) resulted in mutants with different phenotypes to a wide range of antimicrobials even unrelated to the selective agent. Most Biocide-resistant mutants showed increased susceptibility to compounds acting on the cell wall (β-lactams) or the cell membranes (poly-L-lysine, polymyxin B, colistin or toxic anions). Mutations (SNPs) were found in three intergenic regions and nine genes, which have a role in energy production, amino acids, carbohydrates or lipids metabolism, some of them involved in membrane transport and pathogenicity. Comparative transcriptomics of Biocide-resistant mutants showed over-expression of genes encoding efflux pumps (sugE), ribosomal and transcription-related proteins, cold-shock response (cpeE) and enzymes of microaerobic metabolism including those of the phosphotransferase system. Mainly ribosomal, metabolic and pathogenicity-related genes had affected expression in both in vitro-selected Biocide mutants and field Salmonella isolates with reduced Biocide susceptibility. Multiple pathways can be involved in the adaptation of Salmonella to Biocides, mainly related with global stress, or involving metabolic and membrane alterations, and eventually causing “collateral sensitivity” to other antimicrobials. These changes might impact the bacterial-environment interaction, imposing significant bacterial fitness costs which may reduce the chances of fixation and spread of Biocide resistant mutants.
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evaluation of epidemiological cut off values indicates that Biocide resistant subpopulations are uncommon in natural isolates of clinically relevant microorganisms
PLOS ONE, 2014Co-Authors: Ian Morrissey, Tânia Curiao, Marco R Oggioni, Daniel R Knight, Teresa M Coque, Ayse Kalkanci, Jose L MartinezAbstract:To date there are no clear criteria to determine whether a microbe is susceptible to Biocides or not. As a starting point for distinguishing between wild-type and resistant organisms, we set out to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) distributions for four common Biocides; triclosan, benzalkonium chloride, chlorhexidine and sodium hypochlorite for 3319 clinical isolates, with a particular focus on Staphylococcus aureus (N = 1635) and Salmonella spp. (N = 901) but also including Escherichia coli (N = 368), Candida albicans (N = 200), Klebsiella pneumoniae (N = 60), Enterobacter spp. (N = 54), Enterococcus faecium (N = 53), and Enterococcus faecalis (N = 56). From these data epidemiological cut-off values (ECOFFs) are proposed. As would be expected, MBCs were higher than MICs for all Biocides. In most cases both values followed a normal distribution. Bimodal distributions, indicating the existence of Biocide resistant subpopulations were observed for Enterobacter chlorhexidine susceptibility (both MICs and MBCs) and the susceptibility to triclosan of Enterobacter (MBC), E. coli (MBC and MIC) and S. aureus (MBC and MIC). There is a concern on the potential selection of antibiotic resistance by Biocides. Our results indicate however that resistance to Biocides and, hence any potential association with antibiotic resistance, is uncommon in natural populations of clinically relevant microorganisms.
Mike Waldock - One of the best experts on this subject based on the ideXlab platform.
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Antifouling paint booster Biocides in UK coastal waters: Inputs, occurrence and environmental fate
Science of the Total Environment, 2002Co-Authors: Kevin V. Thomas, Mathew McHugh, Mike WaldockAbstract:This study considered the inputs of antifouling paint booster Biocides into the aquatic environment directly from painted hulls and high pressure hosing operations, the occurrence of booster Biocides in marinas, harbours and docks, and the influence of degradation and water-sediment partition on their environmental fate. Irgarol 1051, the Irgarol 1051 degradation product GS26575, diuron, and the diuron degradation products 1-(3-chlorophenyl)-3,1-dimethylurea (CPDU), 1-(3,4-dichlorophenyl)-3-methylurea (DCPMU) and 1-(3,4-dichlorophenyl)urea (DCPU) were all detected at measurable concentrations in surface waters. Irgarol 1051, GS26575 and diuron were also detected in bottom sediments. A preliminary study of Biocide input during both normal use and foreshore hull hosing showed that hosing may be a significant point source input and also be a cause for future concern since much of this input is in the form of paint particles. Field based measurements and laboratory experiments showed that Irgarol 1051 and diuron persist in the water column, due to a low affinity to partition onto sedimentary material and high resistance to degradation. Other Biocides such as chlorothalonil, dichlofluanid, and Sea-Nine 211 were all found to be rapidly removed from the water column and be less persistent. Copyright ?? 2002 Elsevier Science B.V.
Ioannis Konstantinou - One of the best experts on this subject based on the ideXlab platform.
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antifouling paint booster Biocide contamination in greek marine sediments
Chemosphere, 2002Co-Authors: T A Albanis, Dimitra A Lambropoulou, Vasilios A Sakkas, Ioannis KonstantinouAbstract:Abstract Organic booster Biocides were recently introduced as alternatives to organotin compounds in antifouling products, after restrictions imposed on the use of tributyltin in 1987. In this study, the concentrations of three Biocides commonly used as antifoulants, Irgarol 1051 (2-methylthio-4-tertiary-butylamino-6-cyclopropylamino- s -triazine), dichlofluanid ( N -dichlorofluoromethylthio- N ′ , N ′ -dimethyl- N -phenyl sulphamide) and chlorothalonil (2,4,5,6-tetrachloro isophthalonitrile) were determined in sediments from ports and marinas of Greece. Piraeus (Central port, Mikrolimano and Pasalimani marinas), Thessaloniki (Central port and marina), Patras (Central port and marina), Elefsina, Igoumenitsa, Aktio and Chalkida marinas were chosen as representative study sites for comparison with previous monitoring surveys of Biocides in coastal sediments from other European countries. Samples were collected at the end of one boating season (October 1999), as well before and during the 2000 boating season. All the compounds monitored were detected at most of sites and seasonal dependence of Biocide concentrations were found, with maxima during the period June–September, while the winter period (December–February) lower values were encountered. The concentrations levels ranged from 3 to 690 ng/g dw (dry weight). Highest levels of the Biocides were found in marinas (690, 195 and 165 ng/g dw, for Irgarol, dichlofluanid and chlorothalonil respectively) while in ports lower concentrations were observed. Antifouling paints are implicated as the likely sources of Biocides since agricultural applications possibly contributed for chlorothalonil and dichlofluanid inputs in a few sampling sites.
A. D. Russell - One of the best experts on this subject based on the ideXlab platform.
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Biocide use and antibiotic resistance the relevance of laboratory findings to clinical and environmental situations
Lancet Infectious Diseases, 2003Co-Authors: A. D. RussellAbstract:Antibiotics are used as chemotherapeutic drugs, and Biocides are used as antiseptics, disinfectants, and preservatives. Several factors affect biocidal activity, notably concentration, period of contact, pH, temperature, the presence of interfering material, and the types, numbers, location, and condition of microorganisms. Bacterial cells as part of natural or artificial (laboratory) biofilm communities are much less susceptible than planktonic cells to antibiotics and Biocides. Assessment of biocidal activity by bactericidal testing is more relevant than by determination of minimum inhibitory concentrations. Biocides and antibiotics may show some similarities in their mechanisms of action and common mechanisms of bacterial insusceptibility may apply, but there are also major differences. In the laboratory, bacteria can become less susceptible to some Biocides. Decreased resistance may be stable or unstable and may be accompanied by a low-level increase in antibiotic resistance. Laboratory studies are useful for examining stress responses and basic mechanisms of action and of bacterial insusceptibility to antibacterial agents. Translation of such findings to the clinical and environmental situations to provide evidence of a possible relation between Biocide use and clinical antibiotic resistance is difficult and should be viewed with caution.
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Mechanisms of bacterial insusceptibility to Biocides.
American Journal of Infection Control, 2001Co-Authors: A. D. RussellAbstract:Abstract Bacterial insusceptibility to Biocides is of two types, intrinsic and acquired. Intrinsic insusceptibility is a natural property of an organism and is shown by bacterial spores, mycobacteria, and gram-negative bacilli. Cellular impermeability is a major factor, and in some cases active efflux pumps play an important role. A special example is that of phenotypic (physiological) adaptation to intrinsic resistance found in bacteria present in biofilms. Acquired resistance arises through mutation or via the acquisition of plasmids or transposons; efflux of Biocide is a major mechanism, although plasmid-mediated inactivation has also been shown to occur. An additional aspect that must be considered is the stringent response elicited in bacteria on exposure to inimical agencies. There is a possible linkage between certain Biocides and antibiotic resistance under experimental conditions. (Am J Infect Control 2001;29:259-61)
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Plasmids and bacterial resistance to Biocides.
Journal of Applied Microbiology, 1997Co-Authors: A. D. RussellAbstract:Plasmid-encoded fu1 bacterial resistance to antibiotics and to anions and cations (including important mercurial and silver compounds) has been widely studied. Plasmid-mediated resistance to organic cationic agents which are important Biocides has been described for chlorhexidine and quaternary ammonium compounds (and also for the less important acridines, diamidines and ethidium bromide) in antibiotic-resistant Staphylococcus aureus and Staph. epidermidis strains. Plasmids may also encode reduced Biocide susceptibility of Gram-negative bacteria, but intrinsic resistance is likely to be of greater significance. Antibiotic resistance and Biocide resistance may be linked but this is not always found clinically.
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Antibiotic and Biocide resistance in bacteria.
Microbios, 1996Co-Authors: A. D. Russell, Day MjAbstract:Antibiotic-resistant bacteria pose an ever-increasing therapeutic problem. The ways whereby bacteria circumvent drug action are many and varied, ranging from intrinsic impermeability to acquired resistance (involving plasmids, transposons and mutations). Antibiotics may be unable to reach susceptible target sites, they may be enzymatically inactivated, modified or expelled or mutations may arise such as to render the target sites insusceptible. Mechanisms of bacterial resistance to Biocides are less well understood but cellular impermeability is a major factor. Plasmid-mediated efflux of cationic antiseptics in antibiotic-resistant Staphylococcus aureus strains has been demonstrated but its role in the resistance of these organisms to the Biocide concentrations used in clinical practice is unclear. An association between resistance to antibiotics and Biocides in Gram-negative bacteria has also been observed but it is often difficult at present to reach definite conclusions about genetic linkages between antibiotic resistance and Biocide resistance.
