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At least 937 records · Page 52Linked to original sources
PubMed1985

The occurrence and significance of Campylobacter jejuni in man and animals.

Campylobacter jejuni, which is now recognized as a discrete species, is a gram negative, microaerophilic, thermophilic, nalidixic acid sensitive, hippurate positive pathogen requiring special selective media for propogation. The organism is widely distributed in avian species, experimental and companion animals and in humans. Mammalian campylobacteriosis is characterized by an enterocolitis of variable severity. The prevalence of the condition is relatively high in young individuals, in underdeveloped countries and in subjects with diarrhea. Food animals, especially poultry, are reservoirs of the organism and infection occurs following consumption of untreated surface water, unpasteurized milk, incompletely cooked meat or other contaminated food products. Close contact with infected immature companion animals is a significant cause of campylobacteriosis in children and direct intrafamilial transmission and occupational infection have been documented. Campylobacteriosis attributable to C. jejuni is a condition of emerging significance which arises principally from deficiencies in hygiene inherent in the environment and in the food chain which extends from domestic animals to the consumer.

Animals↗
PubMed2003

Determination of ochratoxin A in foods: state-of-the-art and analytical challenges.

Ochratoxin A (OTA) can occur in a large variety of commodities (cereals, beans, groundnuts, spices, dried fruits, coffee, beer, wine) and, because of a carry-over effect, in milk, pig blood, liver, and kidney, and poultry meat from animals fed with contaminated feed. Because of the persistence of OTA in the food chain, exposure to the compound is a potential human health hazard. This has prompted adoption of regulatory limits in several countries which, in turn, implies the development of suitable validated and official analytical methods and rapid screening tests for cost-effective food control on a large scale. Liquid chromatography with fluorescence detection (LC-FLD), coupled with immunoaffinity column (IAC) clean-up, is the most widely employed analytical technique. LC coupled with electrospray-ionization mass spectrometry (MS) has detection limits comparable with those of LC-FLD and the selectivity of IAC can be achieved by tandem (MS-MS) or sequential (MS(n)) detection. Synthetic counterparts to natural antibodies in the form of molecularly imprinted polymers seem a promising alternative to IAC for sample preparation. New analytical approaches to rapid, low-cost screening methods, for example those based on biosensors and dip-stick-like kits, are a direction in which innovation can be expected. Analytical methods for evaluation of the occurrence of OTA in foods, human exposure, and risk assessment are critically reviewed.

Animals↗
PubMed1987

Sources and behavior of technetium in the environment.

Technetium is a man-made element produced in increasing amounts during the last decades. The chemical and physical properties of some technetium compounds are considered, and a discussion of possible source terms is included. Literature on the environmental behavior of technetium is reviewed to evaluate its transfer and equilibrium distribution in aquatic and terrestrial ecosystems. Considerable effort has been expended in the last years in order to understand the biogeochemical processes responsible for the long-term behavior of technetium in the environment and its transfer through food chains as well as to identify critical pathways of the long-lived radioisotope Tc-99 from the environment to man.

Environmental Pollution↗
PubMed2001

Antibiotic resistance in Escherichia coli isolates obtained from animals, foods and humans in Spain.

Antibiotic resistance was investigated in 474 Escherichia coli isolates recovered from animal faeces (broilers, pigs, pets, bulls and horses), human faeces (patients and healthy volunteers) and food products of animal origin. E. coli isolates (3260) recovered from human significant infectious samples were also included. There was a high frequency of nalidixic acid, ciprofloxacin and gentamicin resistance in E. coli isolates from broilers (88, 38 and 40%, respectively), and from foods (53, 13 and 17%). High levels of resistance to trimethoprim-sulphamethoxazole and tetracycline have been found in E. coli isolates from broilers, pigs and foods. These data raise important questions about the potential impact of antibiotic use in animals and the possible entry of resistant pathogens into the food chain.

Animals↗
PubMed1997

Variation in transfer factors for stochastic models: soil-to-plant transfer.

The scientific literature is a good source of information about soil-to-plant transfer, usually documented as mean concentration ratios. It does not provide, however, good information about variation in concentration ratio values, because most studies are done with limited numbers of crops and soils. Fortunately, a suitably large and diverse database is available from the International Union of Radioecologists that can be used to investigate variation. It has a total of over 7,000 concentration ratio values for over 22 elements. This paper reports on analysis of the geometric standard deviations obtained from the database. We assert that geometric standard deviation values are comparable and transferable among elements, so that geometric standard deviations calculated from large databases can be applied to other elements when there is a paucity of data. For a fully generic situation, where neither crops nor soil types are known, the geometric standard deviations is typically about 6. This implies a 1,300-fold range to encompass 95% of the data. For concentration ratios obtained for crops of interest on a specific site, the geometric standard deviation values are much lower, about 1.5. This still implies a fivefold range to encompass 95% of the data. Other values of geometric standard deviations for intermediate levels of information are provided. These estimates of geometric standard deviation are important to and appropriate for stochastic simulations of the impacts of soil contamination on crops and subsequent food chains. They are also important to the inclusivity of concentration ratios value distributions for unusual but perhaps important crops and settings.

Agriculture↗
PubMed2006

Food commensal microbes as a potentially important avenue in transmitting antibiotic resistance genes.

The rapid emergence of antibiotic-resistant (ART) pathogens is a major threat to public health. While the surfacing of ART food-borne pathogens is alarming, the magnitude of the antibiotic resistance (AR) gene pool in food-borne commensal microbes is yet to be revealed. Incidence of ART commensals in selected retail food products was examined in this study. The presence of 10(2)-10(7) CFU of ART bacteria per gram of foods in many samples, particularly in ready-to-eat, 'healthy' food items, indicates that the ART bacteria are abundant in the food chain. AR-encoding genes were detected in ART isolates, and Streptococcus thermophilus was found to be a major host for AR genes in cheese microbiota. Lactococcus lactis and Leuconostoc sp. isolates were also found carrying AR genes. The data indicate that food could be an important avenue for ART bacterial evolution and dissemination. AR-encoding plasmids from several food-borne commensals were transmitted to Streptococcus mutans via natural gene transformation under laboratory conditions, suggesting the possible transfer of AR genes from food commensals to human residential bacteria via horizontal gene transfer.

Animals↗
PubMed2000

The assessment of risk to acquired hypothyroidism from exposure to PCBs: a study among Akwesasne Mohawk women.

PCBs are a family of 209 chemical compounds, each of which consists of two benzene rings and 1 to 10 chlorine atoms. Their long-term stability and dispersion into the environment and the food chain have caused concern about their impact on humans and the environment. Native American communities are believed to be at particularly high risk of such exposure since they typically are more dependent than other populations on local fish and game as a food source. We have evidence for a significant excess in incidence and prevalence of hypothyroidism among Mohawks, particularly older women, as compared to other populations. The goal of the current project is to compare serum PCB concentrations to indicators of thyroid function in controls and patients with demonstrated thyroid dysfunction. Studies on experimental animals (rats) have shown significant depression of circulating levels of T4 and moderate reductions in levels of T3 after exposure to PCBs. We are conducting a retrospective observational case-control study. The participants are Mohawk women 30 years of age and older. Controls are participants in an ongoing environmental epidemiology study, whose thyroid hormone tests show a normal function. Our study aims to investigate the association between long-term exposure to PCBs and acquired hypothyroidism, to identify the critical exposure routes and to develop and apply toxic equivalents for thyroid disease for the various PCB congeners. PCB exposure is assessed by ultra-trace, congener-specific determination in blood specimen using GC/ECD. The study is currently ongoing. We have analyzed 46 samples of cases and 75 samples of controls.

Adult↗
PubMed2000

Standardized growth toxicity testing (Cu, Zn, Pb, and pentachlorophenol) with Helix aspersa.

Juvenile Helix aspersa (1 month, 1 g) were exposed for 4 weeks to food contaminated with copper, zinc, lead, and pentachlorophenol. At concentrations observed in contaminated soils, two essential metals at low levels (Cu and Zn) had a dose-dependent sublethal action on growth. Copper inhibited growth dose-dependently between 1000 and 2000 microg small middle dotg(-1) (EC(50)=1200 microg small middle dotg(-1)), whereas zinc had a toxic effect from 4000 microg small middle dotg(-1) (EC(50)=5500 microg small middle dotg(-1)) on. Lead, a nonessential metal, had no negative effect on growth, unlike cadmium (EC(50)=140 microg small middle dotg(-1)), as reported previously. Pentachlorophenol inhibited growth at a concentration of 500 microg small middle dotg(-1) from the fourth week and 1000 microg small middle dotg(-1) from the first week on. The results obtained with these key organisms in the food chain (consumers) complement those obtained with other land invertebrates (earthworms, springtails, wood-lice, etc.). The findings of the present study and those of earlier studies indicate that juvenile snails are useful organisms for testing the sublethal toxicity of chemicals acting via the food, i.e., the main route of toxicant uptake in land animals.

Animals↗
PubMed1994

Farm animals as a putative reservoir for vancomycin-resistant enterococcal infection in man.

Using a highly selective enrichment broth, 62 isolates of vancomycin-resistant Enterococcus faecium were obtained from non-human sources; 35 isolates from raw sewage, 22 from farm animals and 5 from uncooked chickens. All strains possessed the Van A gene, conferring high-level resistance to vancomycin (MIC > or = 256 mg/L). Ribotyping of 42 of these isolates resulted in 14 distinguishable patterns. Two ribotyping patterns were found among isolates from animals and sewage and those from clinical sources. A blood and a urine isolate from separate hospital patients and porcine isolates shared the same ribotyping pattern number 6 and a stool isolate from a patient in the community and sewage isolates shared another pattern, number 10. This finding suggests that animals may serve as a reservoir of vancomycin-resistant enterococci (VRE), which may enter the human food chain. The emergence of VRE in hospital patients may reflect selection of these organisms in the hospital environment by antibiotic usage from which nosocomial spread might occur.

Animals↗
PubMed2004

Chlorinated dibenzo-p-dioxins and dibenzofurans in the Baltic herring and sprat of Estonian coastal waters.

BACKGROUND, AIMS AND SCOPE: The concentration of chlorinated dibenzo-p-dioxins and dibenzofurans in many fish from the Baltic requires monitoring, since it approaches or exceeds the European Union threshold limit value of 4 pg TEQ/g wet weight of fish for human consumption. The concentrations, expressed in TEQs, are important for toxicology and regulations, but hide the concentrations of the individual congeners, which are important for other environmental sciences, source allocation, and for the detection of measurement errors. This report evaluates the results of a survey reported earlier only in the terms of the TEQ concentrations. METHODS: Principal Component Analysis (PCA) was used to reduce the dimensions of the data (17 = 7 chlorinated dibenzo-p-dioxin and 10 chlorinated dibenzofuran congeners) to three principal components. This facilitated the interpretation of the congener profiles. Slopes of the congener concentrations as a function of age of the fish were estimated by least squares regression. The results were compared with a large set of data for lake trout from Lake Ontario. RESULTS AND DISCUSSION: The congener profiles of Baltic herring are less scattered than those of sprat. The profiles of herring from the central Baltic differ from those of herring from the Gulf of Riga and both appear to be affected relatively minimally by the age of the fish. The congener profiles of herring from the western Gulf of Finland are similar to those from the central Baltic, those from middle Gulf of Finland are similar to those from the Gulf of Riga. Both seem to be more affected by age of the fish than the profiles of the first two groups. The concentrations of several pentachloro- and hexachloro-dibenzo-p-dioxins and dibenzofurans increase with the age of the fish CONCLUSION: PCA is a good technique for the evaluation of the congener profiles. The resulting loading and score plots provide a good graphic summary of the multidimensional data. Additional analyses are needed to confirm the observed profile patterns. A comparison with the results of a long-term monitoring from another area shows that the age of the fish is a more important factor than the year of capture. RECOMMENDATION AND OUTLOOK: The surveys should continue for a number of years and the results should be presented and evaluated both in terms of the TEQs as well as in terms of weight concentrations. Since the concentrations do not appear to change very much from year to year, it would be better to carry out surveys only every 3-4 years and, instead, stratify the sampling according to age and gender of the fish, and to analyze replicate extracts by replicate measurements. The inclusion of unmarked replicate samples would be a good quality assurance measure. It would be desirable to analyze additional parts of the food chain in order to understand the fate of the compounds in the ecosystem.

Age Factors↗
PubMed2006

PCR-based strategy to detect contamination with mycotoxigenic Fusarium species in maize.

Contamination of cereals with mycotoxigenic species of Fusarium is an important source of trichothecenes, fumonisins and other mycotoxins which cause serious diseases in human and animals. In addition, these species are phytopathogenic and produce severe losses in cereal yield. Methods for early detection of these Fusarium species are crucial to prevent toxins entering the food chain and are a useful tool in disease management practices. We have developed an integrated protocol for diagnosis of mycotoxigenic Fusarium contamination in maize which can also be used for other cereals. The protocol consisted in an easy and rapid DNA extraction from maize samples (grain and germ), and subsequent group-specific polymerase chain reaction (PCR) assays for genus Fusarium, Gibberella fujikuroi complex, and trichothecene-producing species of Fusarium, that orientate the search of the critical species. We have additionally developed a PCR assay for the identification of F. proliferatum. The primers were designed on the basis of IGS sequence (Intergenic Spacer of rDNA), a multi-copy region in the genome that permits to enhance the sensitivity of the assay in comparison with PCR assays based on single-copy sequences. The suitability of the protocol and the relative efficacy of single and multi-copy sequence-based PCR assays have been tested in a wide range of fumonisin-contaminated maize samples.

DNA Primers↗
PubMed2006

Detection of Enterobacter sakazakii in dried infant milk formula by cationic-magnetic-bead capture.

Enterobacter sakazakii has been associated with life-threatening infections in premature low-birth-weight infants. Contaminated infant milk formula (IMF) has been implicated in cases of E. sakazakii meningitis. Quick and sensitive methods to detect low-level contamination sporadically present in IMF preparations would positively contribute towards risk reduction across the infant formula food chain. Here we report on the development of a simple method, combining charged separation and growth on selective agar, to detect E. sakazakii in IMF. This protocol can reliably detect 1 to 5 CFU of E. sakazakii in 500 g of IMF in less than 24 h.

Bacteriological Techniques↗
PubMed2006

Maternal body burdens of methylmercury impair survival skills of offspring in Atlantic croaker (Micropogonias undulatus).

Methylmercury (MeHg), the organic form of mercury, bioaccumulates easily through the food chain. Fish in high trophic levels can accumulate substantial levels of MeHg and transfer it to their developing eggs. Here, the effects of maternally derived MeHg on the planktonic larval stage of Atlantic croaker were investigated. Adult Atlantic croaker were fed MeHg-contaminated food at three levels: 0, 0.05, and 0.1 mg kg(-1) day(-1) for 1 month. Fish were then induced to spawn and MeHg levels in the eggs were measured (0.04-4.6 ng g(-1)). Behavioral performance of exposed and control larvae was measured at four developmental stages: end of yolk absorption (yolk), end of oil absorption (oil), and 4 and 11 days after oil absorption (oil+4 and oil+11). Behaviors analyzed included survival skills related to foraging and predator evasion: routine behavior (rate of travel, active swimming speed, net-to-gross displacement ratio, and activity) and startle response to a visual and a vibratory stimulus (responsiveness, reactive distance, response distance, response duration, average response speed, and maximum response speed). Maternally transferred MeHg induced concentration-dependent effects on survival skills. Statistical and simulation models applied to predict the ecological consequences of the behavioral effects suggested that maternal transfer of MeHg may substantially lower survival of planktonic stage larvae compared to unexposed larvae. These results also imply that larvae of top predatory fish species, such as blue marlin, may suffer mortality through maternal transfer of MeHg.

Animals↗
PubMed1999

Antibiotic usage in animals: impact on bacterial resistance and public health.

Antibiotic use whether for therapy or prevention of bacterial diseases, or as performance enhancers will result in antibiotic resistant micro-organisms, not only among pathogens but also among bacteria of the endogenous microflora of animals. The extent to which antibiotic use in animals will contribute to the antibiotic resistance in humans is still under much debate. In addition to the veterinary use of antibiotics, the use of these agents as antimicrobial growth promoters (AGP) greatly influences the prevalence of resistance in animal bacteria and a poses risk factor for the emergence of antibiotic resistance in human pathogens. Antibiotic resistant bacteria such as Escherichia coli, Salmonella spp., Campylobacter spp. and enterococci from animals can colonise or infect the human population via contact (occupational exposure) or via the food chain. Moreover, resistance genes can be transferred from bacteria of animals to human pathogens in the intestinal flora of humans. In humans, the control of resistance is based on hygienic measures: prevention of cross contamination and a decrease in the usage of antibiotics. In food animals housed closely together, hygienic measures, such as prevention of oral-faecal contact, are not feasible. Therefore, diminishing the need for antibiotics is the only possible way of controlling resistance in large groups of animals. This can be achieved by improvement of animal husbandry systems, feed composition and eradication of or vaccination against infectious diseases. Moreover, abolishing the use of antibiotics as feed additives for growth promotion in animals bred as a food source for humans would decrease the use of antibiotics in animals on a worldwide scale by nearly 50%. This would not only diminish the public health risk of dissemination of resistant bacteria or resistant genes from animals to humans, but would also be of major importance in maintaining the efficacy of antibiotics in veterinary medicine.

Animal Husbandry↗
PubMed2002

[Are data collected in France sufficient for a quantitative analysis of food-related infections?].

International marketing of animals, animal products and food stuffs and the emergence or re-emergence of food poisoning has raised the risk of international transmission of certain infectious agents. Risk analysis, with its three components, assessment, management, and information, constitutes a new approach to state health policies. To guarantee health safety of the human, animal and plant populations, states can prohibit importation or marketing of food products if their decisions are based on open scientific evidence. Risk assessment is a structured open process evaluating available data designed to modelize transmission of the infectious agent integrating the different elements of the food chain from production to consumption. The assessment process involves four phases, The results of risk assessment depend on the pertinence and the quality of the data used for each of these four phases. Data required to implement risk assessment are unfortunately widely dispersed. The food and agriculture industry, official regulatory agencies, consumer watch organizations, and the scientific community all have useful information for risk assessment. The lack of standard methods to collect, process and diffuse data further complicates the problem.

Data Collection↗
PubMed1996

The facts about the phthalates scare.

Phthalates are a group of chemicals used in industry and present in the environment. The MAFF survey of phthalates found very low levels in all the 15 infant formula brands tested, as well as in the food chain generally. The levels of individual phthalates in formulae are low and the Department of Health has advised there is no health risk to infants. This has been confirmed by the European Commission (EC). Phthalates are fat-soluble and liable to occur in foods such as milk, cheese, meat, fish and eggs as well as infant formulae. Phthalates may also occur in breast milk. The EC has called for more research on phthalates in food and the environment.

Environmental Exposure↗
PubMed1999

A multi-state survey of consumer food-handling and food-consumption practices.

INTRODUCTION: In the United States, foodborne infections cause an estimated 6.5-33 million illnesses a year. Also included in the burden of foodborne illnesses are sequelae such as hemolytic uremic syndrome, Guillain-Barré syndrome, and reactive arthritis. Surveillance for risky food-handling and food-consumption practices can be used to identify high-risk populations, develop educational efforts, and evaluate progress toward risk reduction. DESIGN: In 1995 and 1996, Behavioral Risk Factor Surveillance System interviews of 19,356 adults in eight states (1995: Colorado, Florida, Missouri, New York, and Tennessee; 1996: Indiana, New Jersey, and South Dakota) included questions related to food-handling and/or food-consumption practices. Risky food-handling and food-consumption practices were not uncommon. Overall, 19% of respondents did not adequately wash hands or cutting boards after contact with raw meat or chicken. During the previous year, 20% ate pink hamburgers, 50% ate undercooked eggs, 8% ate raw oysters, and 1% drank raw milk. Men were more likely to report risky practices than women. The prevalence of most risky behaviors increased with increasing socioeconomic status. CONCLUSION: Targeted education efforts may reduce the frequency of these behaviors. Periodic surveillance can be used to assess effectiveness. In addition to consumer education, prevention efforts are needed throughout the food chain including on the farm, in processing, distribution, and at retail.

Adolescent↗
PubMed2003

Size makes a difference.

OBJECTIVE: To elucidate status and trends in portion size of foods rich in fat and/or added sugars during the past decades, and to bring portion size into perspective in its role in obesity and dietary guidelines in Denmark. DATA SOURCES: Information about portion sizes of low-fat and full-fat food items was obtained from a 4-day weighed food record (Study 1). Trends in portion sizes of commercial foods were examined by gathering information from major food manufacturers and fast food chains (Study 2). Data on intakes and sales of sugar-sweetened soft drinks and confectionery were obtained through nation-wide dietary surveys and official sales statistics (Study 3). RESULTS: Study 1: Subjects ate and drank significantly more when they chose low-fat food and meal items (milk used as a drink, sauce and sliced cold meat), compared with their counterparts who chose food and meal items with a higher fat content. As a result, almost the same amounts of energy and fat were consumed both ways, with the exception of sliced cold meat (energy and fat) and milk (fat). Study 2: Portion sizes of commercial energy-dense foods and beverages, and fast food meals rich in fat and/or added sugars, seem to have increased over time, and in particular in the last 10 years. Study 3: The development in portion sizes of commercial foods has been paralleled by a sharp increase of more than 50% in the sales of sugar-sweetened soft drinks and confectionery like sweets, chocolate and ice creams since the 1970s. CONCLUSIONS: Larger portion sizes of foods low in fat and commercial energy-dense foods and beverages could be important factors in maintaining a high energy intake, causing over-consumption and enhancing the prevalence of obesity in the population. In light of this development, portion size ought to take central place in dietary guidelines and public campaigns.

Adolescent↗