Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “FOOD CONTAMINATION”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 397 records · Page 22Linked to original sources

Contaminants in organic and conventional foodstuffs in France.

The aim was to compare the levels of contamination in organic and conventional raw materials. To this end, the level of contamination by heavy metals (lead, cadmium, arsenic, mercury), nitrates and nitrites, and some mycotoxins were monitored. Fifteen products were tested in their organic and conventional forms, including meat, milk, eggs, vegetables and cereals. The median levels of contamination were calculated and compared with the recommended or regulated maximum levels. The maximum levels were exceeded for lead in organic carrots and buckwheat, and in conventional wheat; for cadmium, in both organic and conventional buckwheat; for nitrates, in organic spinach; and for patulin in organic apples. Moreover, contamination of both conventional and organic wheat by deoxynivalenol was observed with a higher level in organic products. However, the health risk for consumers might be real only for the contamination by mycotoxins as the contaminated foods (apples, wheat) are the main contributors to total exposure.

Crops, Agricultural↗

Quantitative detection of type A staphylococcal enterotoxin by Laurell electroimmunodiffusion.

The detection of staphylococcal enterotoxin A by the quantitative technique of electroimmunodiffusion is described. High dilutions of type-specific rabbit antiserum were used in 1% agarose gels, 1 mm thick, and prepared in 0.05-mug barbital buffer, pH 8.6. Volumes of 10 muliters containing 1.5 to 10 ng of toxin were electrophoresed out of 4-mm diameter wells at 5 mA/cm width of gel. The precipitin cones formed were made visible by first immersing the agarose gels in 0.2 M NaCl and then overlaying the surface with the purified globulin fraction of sheep serum against rabbit globulin, followed by soaking of the gels in 1% aqueous cadmium acetate and staining with 0.1% thiazine red in 1% glacial acetic acid. Fully extended cones, 4 to 23 mm in length depending on toxin concentration and antiserum dilution, were developed in 2 to 5 h of electrophoresis, and visualization was achieved within 2 to 3 h. Because the method is qualitative, quantitative, simple, rapid, and sensitive, it offers a practical tool for the detection of small amounts of bacterial toxins in contaminated foods. The method should also qualify as a sensitive detection device in biochemical procedures which attempt to trace, detect, and identify biological substances in nanogram quantities, provided these substances are antigenic and capable of forming a precipitate with their specific antibodies.

Animals↗

Bacteria and the gastrointestinal tract: beneficial and harmful effects.

Bacteria are unique microorganisms that have a variety of physiological functions which are beneficial to human beings. However, bacteria can also be harmful and cause infections if translocated from the gastrointestinal tract to the epithelial tissue following surgery. The process of translocation can lead to surgical wounds becoming contaminated with gastrointestinal microbes such as Escherichia coli, Proteus or Klebsiella species. Bacteria can also cause severe gastrointestinal infections as a consequence of the ingestion of contaminated food. Food-borne bacterial infections can lead to serious consequences for the patient. Nurses managing the care of surgical patients and older people need to be aware of the physiological role that bacteria play but also the detrimental effects of bacterial translocation or ingestion particularly in older people, infants and people who are immunosuppressed.

Bacteria↗

Binding of aflatoxin B1 to bifidobacteria in vitro.

Aflatoxins are mycotoxins that cause health and economic problems when they contaminate food and feed. One potential method for reducing human health effects due to aflatoxin ingestion is to block uptake via binding by bacteria that either make up the normal gut flora or are present in fermented foods in our diet. These bacteria would bind aflatoxin and make it unavailable for absorption in the intestinal tract. Bifidobacteria comprise a large fraction of the normal gut flora, are thought to provide many probiotic effects and are increasingly used in fermented dairy products. These qualities targeted bifidobacteria for studies to determine if various strains of heat-killed bifidobacteria can bind aflatoxin B1 (AFB1) in vitro. The AFB1 binding affinities of various strains of bifidobacteria, Staphylococcus aureus, and Escherichia coli were quantitated utilizing enzyme-linked immunosorbent and [3H]AFB1 binding assays. The bacteria analyzed were found to bind significant quantities of AFB1 ranging from 25% to nearly 60% of the added toxin. The data also suggest that there are reproducible strain differences in AFB1 binding capacity.

Aflatoxin B1↗

Colonic spirochetosis in animals and humans.

Colonic spirochetosis is a disease caused by the gram-negative bacteria Brachyspira aalborgi and Brachyspira pilosicoli. B. pilosicoli induces disease in both humans and animals, whereas B. aalborgi affects only humans and higher primates. Symptoms in humans include diarrhea, rectal bleeding, and abdominal cramps. Colonic spirochetosis is common in third world countries; however, in developed countries, the disease is observed mainly in homosexual males. Terminally ill patients infected with Brachyspira are particularly at risk for developing spirochetemia. Diarrhea, poor growth performance, and decreased feed-to-gain efficiency is seen in pigs with colonic spirochetosis. The disease in chickens is characterized by delayed and/or reduced egg production, diarrhea, poor feed conversion, and retarded growth. Thus, colonic spirochetosis can represent a serious economic loss in the swine and poultry industries. The organisms are transmitted by the fecal-oral route, and several studies have demonstrated that human, primate, pig, dog, or bird strains of B. pilosicoli can be transmitted to pigs, chickens, and mice. B. pilosicoli may be a zoonotic pathogen, and although it has not been demonstrated, there is a possibility that both B. pilosicoli and B. aalborgi can be transferred to humans via contact with the feces of infected animals, meat from infected animals, or food contaminated by food handlers. Neither B. pilosicoli nor B. aalborgi has been well characterized in terms of basic cellular functions, pathogenicity, or genetics. Studies are needed to more thoroughly understand these Brachyspira species and their disease mechanisms.

Animals↗

Influence of Salmonella in pigs preharvest and during pork processing on human health costs and risks from pork.

Salmonellosis in humans is a costly disease traditionally assumed to be associated with exposure to contaminated food. We have developed a farm-to-fork model that allows estimation of the human health costs and risks associated with Salmonella in pork. This analysis focuses on the stages of the pork production chain up to the point of producing a chilled pork carcass. The model predicts the number of human cases of salmonellosis associated with pork (mean, 99,430; 90% confidence interval, 20,970 to 245,560) and the corresponding social costs (mean, $81.53 million; 90% confidence interval, $18.75 million to $197.44 million). Sensitivity and scenario analyses suggest that changes in Salmonella status during processing are more important for human health risk and have a higher benefit:cost ratio when compared with on-farm strategies for Salmonella control. Specifically, benefit:cost ratios are less than 1 (indicating they are not likely to be profitable from a social economic perspective) for the on-farm strategies of vaccination and meal feeding, whereas rinsing carcasses at various temperatures with and without sanitizer all have benefit:cost ratios greater than 1 (indicating they are profitable from a social economic perspective). This type of modeling is useful for evaluation of the relative cost effectiveness of interventions at different points in the food chain when allocating limited food safety dollars and is best used for examining trends and alternative strategies rather than for providing definitive dollar value estimates of risk. The dollar value estimates must be considered in the context of the wide confidence intervals.

Animals↗

Formation of carcinogenic N-nitroso compounds in corn-bread inoculated with fungi.

DMNA, DENA and MBNA are formed in corn-bread which has been inoculated with the most common species of fungi found in foodstuffs of Lin Xian County, Henan Province, such as F. moniliforme, A. flavus and others, and then, added with small amount of NaNO2 after a few days of incubation. These carcinogenic N-nitroso compounds can induce cancer of the liver or/and esophagus in experimental animals. Results of the present study show the capability of some fungi to produce chemical carcinogens as well as mycotoxins in contaminated food, and thus, open a new field of research in cancer etiology.

Aspergillus flavus↗

[Development and application of a method for isolating Escherichia coli O157:H7 in the city of Gualeguaychú].

Culture media, reagents, and commercial kits were compared on artificially contaminated food samples. The objective was to find an isolation method for Escherichia coli O157:H7 sensitive, specific and accessible in terms of cost, requirements of equipments and qualification of the analyst. The adopted scheme consisted in a selective enrichment at 42 degrees C during 18 to 24 h, using an appropriate medium, in accordance with the nature of the sample, followed by a step of immunomagnetic separation and simultaneous isolation on a chromogenic agar and MacConkey sorbitol agar with potassium tellurite and cefixime, during 18-24 h at 37 degrees C. The presumptive colonies were confirmed as E. coli O157 by serological and biochemical tests. Secondly, this methodology was applied to food samples, water, bovine gastric content and manure. A total of 410 samples were studied: 279 from meat, 54 milk and dairy products, 6 from vegetables, 27 water samples and 44 bovine gastric content and manure. The frequency of isolation of E. coli O157:H7 was of 3.9%. The phenotypic and genotypic characterization of the isolates was performed. A simple isolation methodology for E. coli O157 was developed, which proved accessible to food laboratories of lower complexity. This methodology allowed the detection of this pathogen in food and environmental samples in Gualeguaychú City. The role of water as vehicle of infection was also established. The strains harbored the same virulence factors as those recovered from human disease.

Animals↗

[Neonatal infection with Listeria monocytogenes: rare, but serious].

Between 1993 and 2003, three infants, two girls and a boy, were found to have an invasive infection with Listeria monocytogenes. They received intensive care including respiratory and circulatory support, antibiotics, and treatment of the neurological complications when possible. One of the girls survived without sequelae but the other two infants died in the neonatal period. In one of these two cases there was a clear clue to the source of the infection in the dietary history of the mother: she had consumed unpasteurised cow's milk. The mothers ofthe infants that died had developed fever shortly before parturition. In The Netherlands, the incidence of neonatal invasive infection with Listeria is estimated at 1.3 per 100,000 live-born children per year. This figure seems not to have changed in the last 20 years. Because of the risk of this rare but serious infection, dietary advice to pregnant women to avoid possibly contaminated food is still relevant.

Animals↗

Physicochemical data for some selected Fusarium toxins.

Fusarium toxins are a major group of secondary metabolites, produced by several species, that may contaminate food cereals and animal feeds. We describe results of a study in which a number of physicochemical constants for 12 Important Fusarium mycotoxins (zearalenone, diacetoxyscirpenol, T-2 toxin, neosolaniol monoacetate, deoxynivalenol, nivalenol, fumonisin B1, fumonisin B2, moniliformin, fusarenon-X, HT-2 toxin, and beta-zearalenol) were determined. Nuclear magnetic resonance, mass spectrometric, UV spectral, molar absorption coefficients, fluorescence spectra, melting points, and specific rotation data are presented.

Animal Feed↗

[Chernobyl and its consequences--some veterinary medical points of view].

Summing up some recent publications, the author provides a survey about what happened, today's situation in Germany, the relation between food contamination and exposure, recommended generic intervention levels for foodstuffs, and possibilities to reduce contamination in food. Some agricultural counter-measures in the management of a post-accidental situation are especially taken into consideration. It follows that the veterinarian plays an important role in reducing population exposure by radioactive fall out.

Animal Feed↗

Existing and emerging foodborne diseases.

Foodborne diseases, i.e. illnesses due to contaminated food, are one of the most widespread problems of the contemporary world. They are toxic or infectious by nature and are caused by agents which enter the body through the ingestion of contaminated food or water. These agents can be chemical like pesticide residues and toxic metals or biological like pathogenic microorganisms. Foods contaminated by biological agents are, however, the major cause of foodborne disease. Data recorded in different countries show that the incidence of some of these diseases has increased dramatically over the past few years, but because of under-reporting the data are of limited value and cannot be compared between countries. In most countries, individual cases of illness are usually not reported. A sentinel surveillance system, started as a pilot study in the Netherlands, was shown to be feasible for the registration of some foodborne infections. Based on this study, it can be estimated that each year Salmonella and Campylobacter cause respectively about 12,000 and 25,000 cases of acute enteritis per million. Case-control studies clearly implicate poultry products as an important source of acute enteritis. New developments in food production and changing trends in food consumption lead to the emergence of new hazards. Additionally, because the population is aging and there has been an increase in the number of individuals with underlying diseases, the state of public health is deteriorating. Campylobacter, Salmonella enteritidis and enterohemorrhagic Escherichia coli are examples of microorganisms that have the opportunity to increase as a consequence of intensive husbandry. Listeria monocytogenes is an example of an organism that causes disease in immunosuppressed individuals.

Animals↗

On-farm contamination of animals with chemical contaminants.

Food products should not contain unsafe levels of chemical contaminants. However, it is not possible to monitor each and every one of the many thousands of chemicals that are used in our advanced societies. Chemical contaminants in foodstuffs of animal origin may be classified into three categories: natural contaminants (e.g. mycotoxins), environmental contaminants linked to industrialisation and/or urbanisation (e.g. dioxins and dioxin-like compounds) and authorised chemical products (e.g. residues of veterinary medical products). Chemical hazards may contaminate foodstuffs of animal origin all the way from farm to fork. Contamination may occur in any of the different production systems, and it is difficult to make comparisons between production systems (e.g. extensive versus intensive farming systems) with regard to food safety. Even when we take into account the latest analytical methods, which can detect ever-smaller quantities of residues, the relative importance of chemical contaminants seems to have declined during recent decades due to improvements in information and prevention. Nonetheless, individual incidents can never be ruled out and may have serious economic, health or social repercussions. Particular attention must be paid to chemical hazards, in order to reduce as much as possible the risks to livestock and to the consumer. Continued monitoring and periodic reassessment of risks posed by these contaminants (at the national level) are needed to detect or anticipate new problems, so that appropriate actions can be taken in the interest of public health. More attention should be paid to the production of detailed information, especially with regard to background data (e.g. the objectives of the monitoring, sampling methods, chemicals to be analysed, analytical methods, detection limits, raw data and specified units), in order to obtain a better basis for risk assessment. Such risk assessment provides control authorities with an effective tool for the exchange of information and measures to be taken to ensure food safety.

Animal Husbandry↗

Contamination of foods by food handlers: experiments on hepatitis A virus transfer to food and its interruption.

Hepatitis A virus (HAV) is an important pathogen which has been responsible for many food-borne outbreaks. HAV-excreting food handlers, especially those with poor hygienic practices, can contaminate the foods which they handle. Consumption of such foods without further processing has been known to result in cases of infectious hepatitis. Since quantitative data on virus transfer during contact of hands with foods is not available, we investigated the transfer of HAV from artificially contaminated fingerpads of adult volunteers to pieces of fresh lettuce. Touching the lettuce with artificially contaminated fingerpads for 10 s at a pressure of 0.2 to 0.4 kg/cm(2) resulted in transfer of 9.2% +/- 0.9% of the infectious virus. The pretreatments tested to interrupt virus transfer from contaminated fingerpads included (i) hard-water rinsing and towel drying, (ii) application of a domestic or commercial topical agent followed by water rinsing and towel drying, and (iii) exposure to a hand gel containing 62% ethanol or 75% liquid ethanol without water rinsing or towel drying. When the fingerpads were treated with the topical agents or alcohol before the lettuce was touched, the amount of infectious virus transferred to lettuce was reduced from 9.2% to between 0.3 and 0.6% (depending on the topical agent used), which was a reduction in virus transfer of up to 30-fold. Surprisingly, no virus transfer to lettuce was detected when the fingerpads were rinsed with water alone before the lettuce was touched. However, additional experiments with water rinsing in which smaller volumes of water were used (1 ml instead of 15 ml) showed that the rate of virus transfer to lettuce was 0.3% +/- 0.1%. The variability in virus transfer rates following water rinsing may indicate that the volume of water at least in part influences virus removal from the fingerpads differently, a possibility which should be investigated further. This study provided novel information concerning the rate of virus transfer to foods and a model for investigating the transfer of viral and other food-borne pathogens from contaminated hands to foods, as well as techniques for interrupting such transfer to improve food safety.

Adult↗

Reasoning about food and contamination.

This article examines strategies that are used to reason about food and contamination. In Experiment 1, Ss refrained from choosing a substance that had been given a "poison" label when the intent of the labeler was ambiguous or malicious but preferred this substance when a rationale was provided that dispelled the implication that there once might have been contaminants present. Experiment 2 was designed to compare the effects of safety on conditional reasoning in food and food-irrelevant contexts. When the safety issue was relevant to food in the form of contamination, subjects were most likely to use formal logic in reasoning. A similar pattern of responses was found in Experiment 3 on tasks for which subjects' ratings of their experience of contexts were matched for plausibility, experience, and danger. The results are discussed in terms of an adaptive constraint that facilitates rationality in reasoning within the food domain.

Adult↗

Control of chemical contaminants in foods: past, present, and future.

In the late 1930s and early 1940s, almost the only analyses carried out for chemical contaminants in foods were for lead arsenate and other arsenical pesticides in fruits. Since then, a tremendous expansion has occurred in the types of chemical contaminants found in foods and in the activities of the U.S. Food and Drug Administration and other organizations responsible for monitoring and controlling the presence of these contaminants in the food supply. This paper describes the findings and control of additional chemical contaminants in foods, including synthetic pesticides, PCBs (polychlorinated biphenyls), other industrial chemicals, fungal metabolites such as aflatoxins, toxic metals, and radionuclides. The common characteristics of problems connected with these different types of contaminants include uncontrolled entry into the food supply, incidents causing extreme public worry, and near impossibility in removing these contaminants from the food supply. Problems may also arise from new technologies and environmental developments. New approaches beyond ordinary regulatory activities are being used to meet these problems. Broader analytical methods requiring less time and faster and more sophisticated toxicological methods are needed to assess the hazard of these environmental food contaminants.

Drug Stability↗

Dioxin contamination in food. Bayreuth, Germany, from September 28 to October 1, 2000.

Dioxin and PCB monitoring programs for food and feeding stuff in most countries of the world, including many European Countries are currently inadequate. Better control of food production lines and food processing procedures is needed to minimize entry of dioxin to the food chain and will help to avoid dioxin contamination accidents. This would also improve the ability to trace back a possible contamination to its source. European guidelines for monitoring programs should be established to ensure comparable and meaningful results. These guidelines should define the minimum requirements for the design of monitoring programs, analytical methods, and quality assurance. Though data from Northern Europe shows that the general population exposure to dioxin and PCB has decreased during the last ten years these compounds continue to be a risk of accidental contamination of the food chain. The most prominent recent example is the Belgian dioxin contamination of feeding stuff in 1999. The Belgian dioxin contamination was not detected due to dioxin monitoring programs but by their direct biological effects seen in animals. Four other cases of dioxin contamination have been detected in Europe since 1997 due to local monitoring programs. One of them (citrus pulp pellets 1998) was in a much larger scale than the Belgian dioxin contamination. The general population's exposure to dioxins and PCBs is still in the same range (1-4 pg WHO-TEQ/kg body weight and day) as the recently revised WHO tolerable daily intake (TDI). There is concern that short-term high level exposure to dioxins, furans, and PCB may cause biological effects on the human fetal development and further research is required. Further actions to control sources building on considerable advances already made in many countries may need to be supplemented by measures to prevent direct contamination of feeding stuff or food to reduce general population exposure further.

Animal Feed↗

Food policies: a threat to health?

Food policies deliver large quantities of food relatively safely, but they are failing to deliver healthy diets. Policies fall into three broad categories: the supply of sufficient amounts of food (food security); the provision of food free from contamination (food safety); the provision of a healthy diet available to all (nutritional quality). These three aspects are dealt with by institutions that rarely engage with each other, let alone coordinate their strategies. Greater financial support has been given to agricultural policy than to any other joint EU endeavour. In the last decade food safety has dominated headlines and has influenced recent changes to EU food policies. New food authorities and agencies have been established and ministerial responsibilities have been redefined. Yet, it is nutrition, or rather 'mis-nutrition', that is the largest single cause of death and disease within the region, and indeed worldwide. This need not be the case. Nutrition and dietary policies may find themselves in close alliance with policies for sustainable agriculture. However, the change in thinking that will be required will mean reconsidering the role of commercial food production. Successful nutrition policies may yet prove to be the next major step in the improvement of public health.

Agriculture↗