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1.
Artigo em Inglês | MEDLINE | ID: mdl-22934994

RESUMO

The level of polychlorinated biphenyls (PCBs) contamination in ready meals was investigated to determine exposure compared to other foodstuffs. Chilled ready meals from nine categories (ambient, Chinese, Indian, Traditional UK, Italian, American Tex-Mex, Vegetarian and Organic), and three samples within each category were Soxhlet extracted in triplicate with hexane for 24 h, followed by a clean-up on deactivated silica gel. The cleaned extracts were concentrated to 1 ml under N(2) gas and analyzed on gas chromatography mass spectrometry (GC-MS) for 7 target PCBs (congeners 28, 52, 101, 118, 153, 138, and 180). Individual congener concentrations ranged from non-detectable to 0.40 ng g(-1) (wet weight). The cumulative concentration of all congeners (ΣPCBs) ranged between 0.20 and 1.00 ng g(-1) (wet weight). These values translate into exposure levels of less than 1 µg kg(-1)day(-1) for reference men and women of 70 and 57 kg, respectively. This preliminary study demonstrates that ready meals, like many other foods, are contaminated by PCBs and may represent an important route of human exposure given contemporary changes in consumer food choice. Even though low levels of contamination were observed, long-term exposure for population groups consuming a high volume of ready meals may have cause for concern regarding chronic health risks.


Assuntos
Exposição Ambiental , Poluentes Ambientais/análise , Fast Foods/análise , Contaminação de Alimentos/análise , Bifenilos Policlorados/análise , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Humanos
2.
Int J Neuropsychopharmacol ; 13(10): 1397-410, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20667171

RESUMO

Several chromosomal regions have been linked to bipolar disorder (BD). However, the search for specific genes has been hampered by inconsistent findings, partly due to genetic and phenotypic heterogeneity. We focused on lithium-responsive bipolar patients, a subgroup thought to be more homogeneous and conducted a multistage study including an initial linkage study followed up by fine mapping and gene expression. Our sample consisted of 36 families (275 genotyped individuals, 132 affected) recruited through probands who were responders to long-term lithium treatment. We conducted a genome-wide scan with 811 microsatellite markers followed by fine mapping. Gene expression studies of candidate regions were conducted on six post-mortem prefrontal brain regions of 20 individuals (8 BD and 12 controls). We identified regions 3p25, 3p14 and 14q11 as showing the highest genome-wide linkage signal (LOD 2.53, 2.04 and 3.19, respectively). Fine mapping provided further support for 3p25, while only modest support was found in the other two regions. We identified a group of synaptic, mitochondrial and apoptotic genes with altered expression patterns in BD. Analysis of an independent microarray dataset supported the implication of synapse-related and mitochondrial genes in BD. In conclusion, using two complementary strategies, we found evidence of linkage to lithium-responsive BD on 3p25, 3p14 and 14q11 as well as significantly dysregulated genes on these regions suggesting altered synaptic and mitochondrial function in BD. Further studies are warranted to demonstrate the functional role of these genes in BD.


Assuntos
Transtorno Bipolar/genética , Expressão Gênica , Sinapses/genética , Adulto , Antimaníacos/uso terapêutico , Encéfalo/metabolismo , Mapeamento Cromossômico , Feminino , Ligação Genética , Genótipo , Humanos , Lítio/uso terapêutico , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade
3.
J Environ Sci Health B ; 43(5): 410-21, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18576222

RESUMO

This study reports on the potential for gastrointestinal (GI) mobilization and bioavailability of food-borne PCBs in humans. The development and validation of a GI simulator and operational protocols, developed in compliance with the requirements of German DIN 19738 risk assessment test procedure, are presented. Food, naturally contaminated with PCBs, was homogenized with simulated saliva fluid and shaken in the GI simulator with simulated gastric fluids (containing pepsin, mucine) for 2 h at 37 degrees C. Afterwards, the simulated intestinal fluids (containing pepsin, mucine, trypsin, pancreatin, bile) were added and the mixture shaken for a further 6 h prior to centrifugation and filtration using Buchner funnels to separate the undigested GI residues from GI fluids. PCBs were recovered from GI residues and fluids by Soxhlet and liquid-liquid extraction respectively, cleaned up using silica-SFE, and analyzed by gas chromatography mass spectrometry detection (GC-MSD). Detailed studies with fish indicate variations in mobilization and bioavailability of Sigma PCBs (28, 52, 101, 118, 153, 138 and 180). For example, the bioavailable fractions (fractions mobilized) in mackerel, salmon, crab and prawn were 0.77, 0.60, 0.54, and 0.72 respectively of the Sigma PCBs initially present in these food samples. The bioavailable fraction was dependent on the physicochemical characteristics of the PCBs. In mackerel bioavailable fractions for individual PCB congeners ranged from 0.47-0.82, from 0.30-0.70 in salmon, 0.44-0.64 in crab and in prawn from 0.47-0.77. Future studies will focus on understanding better, the variability in bioavailable fractions to be expected for different foodstuffs, in addition to tissue culture techniques using human gut cell lines to investigate a simultaneous mobilization and absorption of food-borne PCBs.


Assuntos
Poluentes Ambientais/farmacocinética , Contaminação de Alimentos , Suco Gástrico/metabolismo , Trato Gastrointestinal/metabolismo , Bifenilos Policlorados/farmacocinética , Disponibilidade Biológica , Poluentes Ambientais/análise , Poluentes Ambientais/toxicidade , Cromatografia Gasosa-Espectrometria de Massas , Suco Gástrico/efeitos dos fármacos , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/patologia , Humanos , Bifenilos Policlorados/análise , Bifenilos Policlorados/toxicidade , Medição de Risco , Fatores de Tempo
4.
J Environ Sci Health B ; 43(5): 422-8, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18576223

RESUMO

Food consumption has been widely reported to be the main source of human exposure to PCBs. A total of 47 samples of food products on sale in supermarkets in the United Kingdom were thus analyzed for PCBs to determine residual levels in oil and oil-based products. The objective was to compare the measured levels of total PCBs (Sigma PCBs) in food products to those reported in various environmental compartments. Combined extraction and online clean up was achieved using Accelerated Solvent Extraction (ASE) to recover target analytes for analysis by GC-MSD (gas chromatography mass spectrometry). Sigma PCBs (ng/g) in each product were in the ranges of 4.73-44.38 edible oil; 1.40-6.18 mayonnaise; 1.21-6.25 salad cream; 1.28-5.64 seafood sauce, and 0.97-15.08 exotic dressing. The level of human exposure to PCBs in all products was < 1 microg/kg body weight/day when considering a 70 kg male or 57 kg female, possibly reflecting the reported decline of PCBs in the environment.


Assuntos
Peso Corporal/efeitos dos fármacos , Gorduras Insaturadas na Dieta , Poluentes Ambientais , Óleos/química , Bifenilos Policlorados , Peso Corporal/fisiologia , Poluentes Ambientais/análise , Poluentes Ambientais/metabolismo , Poluentes Ambientais/toxicidade , Feminino , Humanos , Masculino , Bifenilos Policlorados/análise , Bifenilos Policlorados/metabolismo , Bifenilos Policlorados/toxicidade , Solventes/química , Fatores de Tempo
5.
Chemosphere ; 68(7): 1352-8, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17320929

RESUMO

Enhanced treatments of sewage sludge produce a more manageable product for agricultural use by stabilizing the material, removing water, and reducing the possibility of pathogen transfer. We investigated the impact of pilot-scale composting and drying of sludge on physicochemical characteristics and on the concentrations of some organic contaminants. During the 143 day composting procedure, organic matter fell 22% and moisture by half. Concentrations of 4-nonylphenols (4-NPs) fell by 88% and di-(2-ethylhexyl) phthalate (DEHP) by 60%; losses continued throughout the procedure. Losses of total polychlorinated biphenyls (PCBs) were 11%, mostly from the lower molecular weight congeners, suggesting volatilization as the most likely loss mechanism. The drying process was much shorter, 40 days, yet organic matter content decreased by 27% and moisture by 85%. Losses of 4-NPs (39%) and DEHP (22%) were less than in composting and stopped when moisture content became constant. There were no losses of PCBs. Both treatments are simple, practical procedures that reduce the volume of waste and are applicable in situ on farms. Composting would be the method of choice for reducing organic contaminants but requires much longer times than drying.


Assuntos
Dietilexilftalato/química , Fenóis/química , Bifenilos Policlorados/química , Esgotos/química , Solo/análise , Anaerobiose
6.
J Hazard Mater ; 144(1-2): 340-7, 2007 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-17113229

RESUMO

The biodegradation of 16 US. EPA-listed polycyclic aromatic hydrocarbons (sigma PAHs), with accompanying humification and microbial community structure changes during simulated in-vessel composting-bioremediation of an aged coal-tar-contaminated soil amended with green waste were studied over 56 days. The experimental design compared one constant temperature profile (TC=38 degrees C) with three variable temperature profiles (TP1, TP2 and TP3), including treatment at 70 degrees C to comply with regulatory requirements. Greatest sigma PAHs removal (75.4+/-0.1%; k(1)=0.026 day(-1), R(2)=0.98) occurred at TC=38 degrees C compared to all variable temperature profiles TP1 (62.1+/-11.0%; k(1)=0.016 day(-1), R(2)=0.93), TP2 (71.8+/-8.2%; k(1)=0.021 day(-1), R(2)=0.95) and TP3 (45.3+/-9.7%; k(1)=0.010 day(-1), R(2)=0.91). This study proved that using thermophilic temperatures (70 degrees C) towards the end of in-vessel composting processes (TP2) resulted in greater sigma PAHs removal than using other variable temperature profiles (TP1, TP3), as long as the increase was stepwise via an intermediate temperature (55 degrees C). Phospholipid fatty acid (PLFA) signatures indicated that use of thermophilic temperatures towards the end of the in-vessel composting-bioremediation (TP2) resulted in a higher fungal to bacterial PLFA ratio and a lower Gram-positive to Gram-negative (G(+)/G(-)) bacterial ratio. Fluorescence excitation-emission matrix (EEM) showed the presence of peaks typical of humic-like (Ex/Em wavelength pair approximately 340/460 nm) and fulvic-acid-like (Ex/Em wavelength pair approximately 245/460 nm) substances, indicating mineralization and/or maturation of the compost. Varying the temperature during in-vessel composting to comply with regulatory requirements for pathogen control, promoted contaminant biodegradation, microbial activity and compost maturation.


Assuntos
Alcatrão , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes do Solo/metabolismo , Solo , Bactérias/metabolismo , Biodegradação Ambiental , Reatores Biológicos , Ácidos Graxos/metabolismo , Fungos/metabolismo , Substâncias Húmicas , Temperatura
7.
Environ Pollut ; 141(3): 459-68, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16246473

RESUMO

In-vessel composting of polycyclic aromatic hydrocarbons (PAHs) present in contaminated soil from a manufactured gas plant site was investigated over 98 days using laboratory-scale in-vessel composting reactors. The composting reactors were operated at 18 different operational conditions using a 3-factor factorial design with three temperatures (T, 38 degrees C, 55 degrees C and 70 degrees C), four soil to green waste ratios (S:GW, 0.6:1, 0.7:1, 0.8:1 and 0.9:1 on a dry weight basis) and three moisture contents (MC, 40%, 60% and 80%). PAH losses followed first order kinetics reaching 0.015 day(-1) at optimal operational conditions. A factor analysis of the 18 different operational conditions under investigation indicated that the optimal operational conditions for degradation of PAHs occurred at MC 60%, S:GW 0.8:1 and T 38 degrees C. Thus, it is recommended to maintain operational conditions during in-vessel composting of PAH-solid waste close to these values.


Assuntos
Alcatrão , Recuperação e Remediação Ambiental/métodos , Resíduos Industriais , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Substâncias Húmicas , Umidade , Solo , Temperatura , Fatores de Tempo
8.
Chemosphere ; 64(5): 839-47, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16330081

RESUMO

In-vessel composting of an aged coal-tar contaminated soil from a manufactured gas plant site was investigated over 98days using laboratory-scale in-vessel composting reactors. The composting reactors were operated at 18 different operational conditions using a logistic three-factor factorial design with three temperatures (T=38, 55 and 70 degrees C), four soil to green waste ratios (S:GW; 0.6:1, 0.7:1, 0.8:1 and 0.9:1 on a dry weight basis) and three moisture contents (MC; 40%, 60% and 80%). Excitation-emission matrix (EEM) fluorescence spectroscopy was used to investigate organic matter dynamics in the composting mixture. The results of this investigation indicated that formation of humic substances can be monitored by fluorescence excitation-emission matrix, and provided evidence of progressive mineralization or humification of the composting mixture. Peak excitation wavelength shifts and peak fluorescence intensity can both be used as indicators to monitor the humification or maturation of compost. Finally, the fluorescence index can be applied to investigate the origin of humic substances and fulvic acids, and the humification or maturation of compost.


Assuntos
Alcatrão/análise , Compostos Orgânicos/análise , Poluentes do Solo/análise , Solo/análise , Espectrometria de Fluorescência/métodos , Benzopiranos/análise , Benzopiranos/metabolismo , Biodegradação Ambiental , Alcatrão/metabolismo , Substâncias Húmicas/análise , Compostos Orgânicos/química , Poluentes do Solo/metabolismo , Temperatura , Fatores de Tempo
9.
Chemosphere ; 63(4): 541-53, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16297429

RESUMO

The residues of polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in soils from organic farms and their uptake by four varieties of organic-produced potatoes and three varieties of organic carrots from England were investigated. Samples of the soils, crop peels and cores were all Soxhlet-extracted in triplicate, cleaned up by open-column chromatography and analysed by a multi-residue analytical method using gas chromatography with mass selective detection. The concentrations of PAHs, PCBs and OCPs in soils from organic farms ranged from 590+/-43 to 2301+/-146 microg/kg, 3.56+/-0.73 to 9.61+/-1.98 microg/kg and 52.2+/-4.9 to 478+/-111 microg/kg, respectively. Uptake by different crop varieties were 8.42+/-0.93 to 40.1+/-4.9 microg/kg sigmaPAHs, 0.83+/-0.19 to 2.68+/-0.94 microg/kg sigmaPCBs and 8.09+/-0.83 to 133+/-27 microg/kg sigmaOCPs. Residue uptake from soils depended on plant variety; Desiree potato and Nairobi carrot varieties were more susceptible to PAH contamination. Likewise, uptake of PCBs and OCPs depended on potato variety. There were significant positive correlations between the PCB and OCP concentrations (P<0.05) in soils and carrots but no significant correlation was found between the concentrations of any contaminants in soils and potatoes. Peeling carrots and potatoes was found to remove 52-100% of the contaminant residues depending on crop variety and the properties of the contaminants. Soil-crop bioconcentration factors (BCFs) decreased with increasing logK(ow) for PAHs up to about 4.5 and for PCBs up to about 6.5, above which no changes were discernible for either class of contaminants. No relationship was observed between soil-crop BCFs and logK(ow) for OCPs, most likely because their concentrations were low and variable.


Assuntos
Hidrocarbonetos Clorados/análise , Resíduos de Praguicidas/análise , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Verduras/química , Agricultura/métodos , Daucus carota/química , Inglaterra , Contaminação de Alimentos , Hidrocarbonetos Clorados/metabolismo , Resíduos de Praguicidas/metabolismo , Bifenilos Policlorados/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes do Solo/análise , Solanum tuberosum/química , Verduras/metabolismo
10.
J Hazard Mater ; 137(3): 1583-8, 2006 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-16797836

RESUMO

The biodegradation of 16 USEPA-listed PAHs (SigmaPAHs) during simulated in-vessel composting-bioremediation of an aged coal-tar-contaminated soil amended with fresh green waste compost (FGWC) collected from two landfill sites in the United Kingdom (UK) were studied over 56 days. The experimental design compared three constant temperature profiles (TC=38, 55 and 70 degrees C) with one variable temperature profile including treatment at 70 degrees C to comply with regulatory requirements (TP1). The highest disappearance of SigmaPAHs was observed in the soil amended with FGWC (53.2% and 48.1% SigmaPAHs disappearance in soil amended with FGWC-Site 1 and FGWC-Site 2, respectively) containing lower initial organic mater (TOM) (Initial TOM(FGWC-Site 1)=25.6+/-0.6%

Assuntos
Alcatrão/química , Alcatrão/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Solo , Reatores Biológicos , Temperatura , Fatores de Tempo , Gerenciamento de Resíduos
11.
Environ Int ; 31(2): 173-8, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15661279

RESUMO

The biodegradation of 16 United States Environmental Protection Agency (USEPA)-listed polycyclic aromatic hydrocarbons (PAHs) present in contaminated soil from a manufactured gas plant site was investigated using laboratory-scale in-vessel composting-bioremediation reactors over 8 weeks. The influence of temperature (T, 38, 55, and 70 degrees C) and soil/green waste ratio (S:GW, 0.6:1, 0.7:1, 0.8:1, and 0.9:1) was investigated. A comparative study using a temperature profile during in-vessel composting-bioremediation to meet current regulatory requirements was also investigated. Temperature and amendment ratio were found to be important operating parameters for PAH removal for in-vessel composting-bioremediation of aged coal tar-contaminated soil. After 8 weeks of continuous treatment, the highest removal of 16 USEPA PAHs was observed at T=38 degrees C and S:GW=0.8:1 (75.2%). Lower removal of 16 USEPA PAHs was observed for temperature profile treatment (60.8%). We recommend that when conventional composting processes using temperature profiles to meet regulatory requirements for pathogen control need to be used, these should start with a prolonged mesophilic stage (6 weeks in this investigation) followed by thermophilic, cooling, and maturation stages.


Assuntos
Alcatrão/química , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Biodegradação Ambiental , Eliminação de Resíduos , Temperatura , Fatores de Tempo
12.
Chemosphere ; 61(9): 1336-44, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15979687

RESUMO

When sewage sludge is added to agricultural land, organic chemicals contaminants are also added. The fate of these chemicals, particularly those shown to have oestrogenic potential, has received much research and regulatory interest in recent years. A method was developed for the analysis of 4-nonylphenols, phthalates, and PCB congeners in soils, mesophilic anaerobially digested dewatered (MADD) sewage sludge, and MADD sludge-amended soil. After Soxhlet-extraction, the 4-nonylphenols and phthalates were separated from the PCBs on an isolute cyanopropyl SPE cartridge and analysed by GC-MS directly. The PCBs were acid treated on a Bakerbond PCB-A cartridge, then passed through a gel filtration column of Biobeads SX-3 resin, before GC-MS analysis. The method was successfully validated and then used for routine analysis, where average recoveries of the surrogate standards were 83+/-17% (4-n-heptylphenol), 96+/-11% (dimethyl-tere-phthalate), 101+/-12% (dibenzyl-phthalate), and 79+/-13% (PCBs 6, 54, 104, 155, and 198).


Assuntos
Poluentes Ambientais/análise , Fenóis/análise , Ácidos Ftálicos/análise , Bifenilos Policlorados/análise , Esgotos/química , Agricultura , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas , Sensibilidade e Especificidade
13.
Waste Manag ; 25(3): 281-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15823743

RESUMO

The biodegradation of 16 polycyclic aromatic hydrocarbons (PAHs), listed as priority pollutants by the USEPA, present in a coal-tar-contaminated soil from a former manufactured gas plant site was investigated using laboratory-scale in-vessel composting reactors to determine the suitability of this approach as a bioremediation technology. Preliminary investigations were conducted over 16 weeks to determine the optimum soil composting temperature (38, 55 and 70 degrees C). Three tests were performed; firstly, soil was composted with green-waste, with a moisture content of 60%. Secondly, microbial activity was HgCl2-inhibited in the soil green-waste mixture with a moisture content of 60%, to evaluate abiotic losses, while in the third experiment only soil was incubated at the three different temperatures. PAHs and microbial populations were monitored. PAHs were lost from all treatments with 38 degrees C being the optimum temperature for both PAH removal and microbial activity. Calculated activation energy values (E(a)) for total PAHs suggested that the main loss mechanism in the soil-green waste reactors was biological, whereas in the soil reactors it was chemical. Total PAH losses in the soil-green waste composting mixtures were by pseudo-first order kinetics at 38 degrees C (k = 0.013 day(-1), R2 = 0.95), 55 degrees C (k = 0.010 day(-1), R2 = 0.76) and at 70 degrees C (k = 0.009 day(-1), R2 = 0.73).


Assuntos
Modelos Teóricos , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes do Solo/metabolismo , Bactérias , Biodegradação Ambiental , Reatores Biológicos , Dinâmica Populacional , Temperatura
14.
Chemosphere ; 76(6): 841-6, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19419750

RESUMO

BACKGROUND: Polychlorinated biphenyls (PCBs) are anthropogenic, organic compounds. Although banned in the 1970s, PCBs are poorly biodegradable and hence ubiquitous in the environment. They accumulate in adipose tissue and are implicated various malignancies, including breast and pancreatic cancer. The hepatobiliary system is the main excretory route for such xenobiotic toxins. Incidence rates of intrahepatic biliary tract cancer are increasing worldwide. Measurement and comparison of PCB levels in bile from human patients with benign and malignant bile duct disease has not previously been done. OBJECTIVES: To compare PCB concentrations in bile from patients with malignant (n=8) and non-malignant (n=7) biliary disease. METHODS AND RESULTS: Fifteen human bile samples, collected endoscopically, were analysed using gas chromatography mass spectrometry for seven target PCB congeners (28, 52, 101, 118, 153, 138, and 180), known to occur in the environment and food. Amongst males, total PCB concentrations in bile ranged from 6 ng mL(-1) (aged 73 years) to 49 ng mL(-1) (aged 90 years); and in females between 8 ng mL(-1) (aged 33 years) to 43 ng mL(-1) (aged 67 years) bile. Although there was no overall difference in mean PCB levels between non-cancer and cancer patients, levels of congener 28 were significantly higher in patients with biliary tract cancer (p<0.05). CONCLUSIONS: Despite the banning of PCBs over 30 years ago, these xenobiotics are present in the bile of patients with biliary disease. PCB levels tend to increase with age, suggesting chronic bioaccumulation. Further research is necessary to investigate the relevance of increased levels of congener 28 in bile in biliary tract cancer.


Assuntos
Bile/química , Neoplasias do Sistema Biliar/química , Poluentes Ambientais/análise , Bifenilos Policlorados/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Poluentes Ambientais/química , Poluentes Ambientais/isolamento & purificação , Feminino , Humanos , Marcação por Isótopo , Masculino , Pessoa de Meia-Idade , Bifenilos Policlorados/química , Bifenilos Policlorados/isolamento & purificação , Xenobióticos/análise , Xenobióticos/química , Xenobióticos/isolamento & purificação
15.
Crit Rev Food Sci Nutr ; 43(3): 287-316, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12822674

RESUMO

Hazard Analysis by Critical Control Points (HACCP) is a systematic approach to the identification, assessment, and control of hazards in the food chain. Effective HACCP requires the consideration of all chemical microbiological, and physical hazards. However, current procedures focus primarily on microbiological and physical hazards, while chemical aspects of HACCP have received relatively little attention. In this article we discuss the application of HACCP to organic chemical contaminants and the problems that are likely to be encountered in agriculture. We also present generic templates for the development of organic chemical contaminant HACCP procedures for selected raw food commodities, that is, cereal crops,raw meats, and milk.


Assuntos
Agricultura , Contaminação de Alimentos/prevenção & controle , Compostos Orgânicos , Gestão da Segurança/métodos , Agroquímicos , Animais , Carne , Leite , Plantas Comestíveis , Controle de Qualidade
16.
J Hepatol ; 37(6): 806-13, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12445422

RESUMO

BACKGROUND/AIMS: The age-standardized mortality rate for hepatocellular carcinoma is increasing in several countries. However, in England and Wales we previously reported an increase in mortality rates from intrahepatic cholangiocarcinoma. Trends in cholangiocarcinoma in most other industrialized countries are unknown. To further study trends in hepatobiliary and pancreatic tumours, we analysed mortality data from the United States, Japan, Australia and Europe. METHODS: Age-standardized mortality rates for men and women for subcategories of liver tumours, tumours of the gall bladder and extrahepatic biliary tree and pancreas from 1979 to 1998 were obtained from the World Health Organization mortality database. RESULTS: We confirmed previously reported increases in hepatocellular carcinoma, but also found increases in other countries, particularly Australia (3-year average rise from 1.20 to 2.27, men). Mortality for intrahepatic cholangiocarcinoma increased in men in all countries studied, with the largest increases in Australia (from 0.10 to 0.70) and England and Wales (from 0.20 to 0.83). CONCLUSIONS: We present a hitherto unreported rise in age-standardized mortality rates from intrahepatic cholangiocarcinoma across four continents. The cause remains uncertain. An impact on the observed trends of improved diagnostic techniques and death certificate misclassification cannot be completely ruled out. Future research should include epidemiological studies to examine possible case-clustering and investigation of potential aetiological and host factors.


Assuntos
Neoplasias do Sistema Biliar/mortalidade , Internacionalidade , Neoplasias Hepáticas/mortalidade , Neoplasias Pancreáticas/mortalidade , Austrália/epidemiologia , Carcinoma Hepatocelular/mortalidade , Colangiocarcinoma/mortalidade , Europa (Continente)/epidemiologia , Feminino , Neoplasias da Vesícula Biliar/mortalidade , Humanos , Japão/epidemiologia , Masculino , Estados Unidos/epidemiologia
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