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 1,279 records · Page 71Linked to original sources
PubMed1986

Cobalt content of foods and diets in a Spanish population (short communication).

The WHO Expert Committee on Food Contaminants has pointed out the need of determining the content of foods in trace elements in order to ascertain their contribution to the total intake of oligoelements through the diet. Since the contents in trace elements depend on the environmental features, it is necessary to carry out systematic determinations of trace elements in foods of local origin in order to know the exposure level of population. This work intends to study the cobalt contribution through the diet. The element intake is calculated from the cobalt content in raw foods after elimination of the non-eatable moiety by flame atomic absorption spectroscopy, after formation of a chelate with ammonium pyrrolidine dithiocarbamate (APDC) and extraction with 4-methyl-2-pentanone (MIBK) according to a procedure developed and verified in a previous paper.

Adolescent↗
PubMed2000

Prevention by vitamin E of DNA fragmentation and apoptosis induced by fumonisin B1 in C6 glioma cells.

Fumonisin B1 (FB1), produced by the fungus Fusarium moniliforme, belongs to a class of sphingosine analogue mycotoxins that occur widely in the food chain. Epidemiological studies have associated consumption of Fusarium moniliforme-contaminated food with human oesophageal cancer in China and South Africa. FB1 also causes equine leucoencephalomalacia. Evidence for induction of apoptosis by FB1 was first obtained when C6 glioma cells were incubated with fumonisin B1 (3-27 microM) causing DNA fragmentation profiles showing DNA laddering in gel electrophoresis and apoptotic bodies revealed by chromatin staining with acridine orange and ethidium bromide. Further confirmation experiments and comet assays have been performed under similar conditions. The results of the comet test show that FB1 at 9 and 18 microM induces respectively 50 +/- 2% and 40 +/- 1% of cells with a comet with an increased tail length of 93 +/- 9 microm and 102 +/- 17 microm respectively. Under these concentrations, FB1 induced DNA fragmentation and laddering and many apoptotic bodies. Pre-incubation of the cells with vitamin E (25 microM) for 24 h before FB1 (18 microM) significantly reduced DNA fragmentation and apoptotic bodies induced by FB1.

Animals↗
PubMed2001

Food irradiation: a public health challenge for the 21st century.

Although the United States food supply is generally considered one of the safest in the world, foodborne illnesses remain a concern. Each year, millions of Americans become ill and as many as 5000 die from foodborne infections. The United States Department of Agriculture estimates that medical treatment and productivity losses associated with foodborne illnesses cost as much as $37 billion annually. Irradiation, which involves exposing food briefly to radiant energy, can reduce or eliminate microorganisms that contaminate food or cause spoilage. So far, only limited quantities of irradiated foods--spices, herbs, dry vegetable seasonings, and some fresh fruits, vegetables, and poultry--have been available in the United States. Major purchasers are health care and food service establishments. The World Health Organization reviewed 500 studies and concluded that food irradiation poses no toxicological, microbiological, or nutritional problems. In more than 40 years, there have been no accidents in North America involving transport of the types of radioactive isotopes used for irradiation.

Food Irradiation↗
PubMedDate not supplied

Influence of food intake on presystemic clearance of drugs.

Many drugs have a low degree of oral bioavailability even though their gastrointestinal absorption is complete. This is because they undergo extensive presystemic metabolic transformation during the first passage of the drug through the gastrointestinal mucosa and the liver. In addition to effects on the absorption of some drugs, food intake has been found to influence the bioavailability of drugs with extensive presystemic metabolic clearance. Extensive presystemic clearance occurs commonly with compounds that are lipophilic bases, e.g. propranolol and amitriptyline, but rarely if ever with lipophilic acids, e.g. salicylic acid and penicillin, except for esters of such acids, e.g. acetylsalicylic acid (aspirin) and pivampicillin. While presystemic clearance of (esterified) acidic drugs is unaffected by food, concurrent food intake markedly reduces presystemic clearance, and thus enhances bioavailability, of several lipophilic bases. Among these are propranolol, metoprolol, labetalol, dixyrazine and hydralazine, which are presystemically metabolised by hydroxylation, glucuronidation and acetylation enzymes systems. In contrast, the bioavailability of lipophilic bases which undergo presystemic dealkylation (amitriptyline, codeine, dextropropoxyphene, prazosin, zimelidine) is unaffected by concurrent food intake. Food intake reduces presystemic clearance of hydralazine and propranolol when these drugs are administered in conventional rapid-release tablets but not when they are given in slow-release formulations. Likewise, coadministration of hydralazine reduces presystemic clearance of rapid-release but not slow-release propranolol. These and other observations favour the view that food may reduce presystemic clearance of (certain) lipophilic basic drugs via transient, complex effects on splanchnic-hepatic blood flow and/or shunt processes, and that the extent of this effect is influenced by the rate of drug delivery to the liver. In addition, these findings refute the notion that the reduced presystemic clearance results from (long-lasting) hepatic enzyme inhibition by some nutrient. On the other hand, repeated intake of specific nutrients (protein) and food contaminants (benzpyrene) can enhance presystemic drug clearance by enzyme induction. Thus, food may exert a dual effect on presystemic drug clearance. A complete evaluation of the influence of food on presystemic drug clearance necessitates bioavailability studies carried out following both single and repeated meals, including different kinds of food prepared by various cooking methods. The influence of food on the presystemic clearance of drugs is most likely to be clinically relevant with drugs having narrow therapeutic margins and/or steep dose-response curves.

Biological Availability↗
PubMed1999

Critical path plan for food and nutrition research required for planetary exploration missions.

In preparation for future planetary exploration, NASA-Johnson Space Center has developed a critical path plan for food and nutrition research needs. The plan highlights the risk factors pertaining to food and nutrition associated with exposure to the space flight environment as well as the possible consequences if no corrective measures are implemented. Included in the plan are the initiating events such as microgravity, remote environment and mission duration, which obviously impact the risk factors. The plan includes points of intervention where mitigating factors can be implemented to avoid outcomes such as malnutrition and unsafe foods. Physiological changes induced by lack of gravity, as well as increased exposure to radiation, may alter nutrient bio-availability, and/or nutrient requirements. An inadequate food system, whether due to technical limitations or nutritional shortcomings, can result in serious consequences. Additionally, microbial and chemical food contamination or psychological factors such as depression may lead to insufficient food intake. Critical questions define areas where further research is required to eliminate or ameliorate the risk from each of those factors. These questions delineate priorities for NASA food and nutrition research for planetary exploration missions.

Aerospace Medicine↗
PubMed2003

Food hygiene practices of food vendors in secondary schools in Ilorin.

This descriptive study was carried out to determine food safety practices among food Vendors in secondary schools in Ilorin. Pre-tested questionnaire and observational checklist were administered to 185 respondents recruited using inclusion and exclusion criteria. One hundred and eighty-two (98.4%) of the subjects were females and only 6(3%) were teenagers. One hundred and two (56.8%) had no formal education while 72(39% had received training on food hygiene. Pre-employment medical examination practice was high 141(76%) but periodic medical examination was low 30(16%). Sixty-one (33%) and seventy-two(39%) respondents prepared food well in advance and reheat food before sale respectively. Vendors who prepared food well in advance (over 4 hours) were found to practise food re-heating more than those who prepared food within 4 hours before sale, and this is statistically significant. The major unhygienic practices observed among the food vendors were poor care of used utensils 100(54%), use of previously used water for washing and cleaning, lack of covering apron among the vendors 128(69%) and lack of wash hand basin for immediate cleaning 61(33%). Only 85(46%) of the respondents used soap and water to clean their utensils while the rest 100(54%) used unhygienic methods to clean their utensils. It was observed that respondents who used soap and water for cleaning, vended food at locations that were relatively closer to water source, compared to other vendors who used other methods to clean their utensils. This is also statistically significant. Unkempt fingernails, skin lesions and poor food protection from flies were some of the food contaminating risk factors observed in the study. The need exists for food vendors and other food handlers to be trained on basic principles of safe food handling.

Adolescent↗
PubMedDate not supplied

Polymerase chain reaction techniques for food allergen detection.

Food allergies represent an important health problem in industrialized countries. Undeclared allergenic foods as contaminants in food products pose a major risk for sensitized persons. Reliable detection and quantification methods for food allergens are necessary to ensure compliance with food labeling and improve consumer protection. The methods currently used for the detection of potential allergens in foods are to target either the allergen itself or a marker that indicates the presence of the offending food. As markers for the presence of potentially allergenic foods or ingredients, specific proteins or DNA fragments are targeted. In routine food analysis, the enzyme-linked immunosorbent assay (ELISA) and the polymerase chain reaction (PCR) in the form of a real-time PCR or in combination with an ELISA have been used. The availability, the characteristics, and some future aspects of DNA-based methods in the rapid and sensitive detection of potentially allergenic food constituents or contaminations are discussed in this review.

Allergens↗
PubMed2006

Towards a harmonized approach for risk assessment of genotoxic carcinogens in the European Union.

The EU Scientific Committees have considered in the past the use of matematical models for human cancer risk estimation not adequately supported by the available scientific knowledge. Therefore, the advice given to risk managers was to reduce the exposure as far as possible, following the as low as reasonably achievable (ALARA) principle. However, ALARA does not allow to set priorities for risk management, as it does not take into consideration carcinogenic potency and level of human exposure. For this reason the European Food Safety Authority (EFSA) has identified as a priority task the development of a transparent, scientically justifiable and harmonized approach for risk assessment of genotoxic carcinogens. This approach, proposed at the end of 2005, is based on the definition of the (MOE), i.e. the relationship between a given point of the dose reponse curve in the animal and human exposure. As point of comparison EFSA recommends the BMDL10, i.e. the lower limit of the confidence interval of the Benchmark Dose associated with an incidence of 10% of induced tumors. Based on current scientific knowkedge, EFSA concluded that a MOE of 10000 or greater is associated with a low risk and low priority for risk management actions. The approach proposed does not replace the ALARA. It should find application on food contaminants, process by-product, and other substances unintentionally present in food. On the other hand, it is not intended to provide a tool for the definition of tolerable intake levels for genotoxic carcinogens deliberately added to food.

Carcinogens↗
PubMed1981

Identification of foreign matter in foods.

It is the purpose of this paper to review and illustrate recent, pertinent, advances in detection methods for those food particle contaminants that have potential as hazards to human health or that elevate the risk for product liability disputes. Sources for the contamination of the human food supply include extraneous particulates associated with raw materials, food handling and packaging processes, as well as extraneous filth from insects and rodents. Likewise, environmental particulates, either airborne or in liquid suspension, can be considered as potential food contaminants. Concern for the quality of human foods relates to the type and quantity of suspected contaminants. To reduce the risk of particle contaminations of all types in human food supplies and to insure high yields of safe, high quality products, industry safeguards include monitoring and identification of foreign matter. Supportive methodology has been developed to detect, separate and identify particle contaminants of many types. Microscopic contaminants are characterized using light microscopy, electron microscopy and allied techniques. Specific applications of these techniques are described in brief detail.

Asbestos↗
PubMed1991

Ochratoxin A as a contaminant in the human food chain: a Canadian perspective.

Penetration of ochratoxin A into the human food chain in Canada was assessed by analysing stored grains, porcine blood and, finally, human blood. The potential for mycological growth and production of ochratoxin A was determined in 164 samples of stored grain (barley, wheat, maize and silage) collected from producers in Manitoba. A total of 34% were found to have the capacity to produce ochratoxin A; 14.5% had concentrations greater than 1.0 mg/kg. In 1988, 1200 blood samples were obtained from swine destined for slaughter in western Canada. High-performance liquid chromatography demonstrated that 3.6% of the 194 blood samples collected in February and March and 4.2% of the 1006 collected in May, June and July had concentrations of ochratoxin A that exceeded 20 ng/ml. In a subsequent survey of porcine blood carried out in 1989-90, 16-65% of the samples had detectable levels of ochratoxin A, at mean concentrations of 5.4-19.4 ng/ml. Subsequently, human blood samples were collected from 159 individuals, 69 of whom had some form of renal impairment. Of the latter, 40% had detectable levels of ochratoxin A, and 12% had concentrations greater than 0.5 ng/ml. Of the non-renal patients, 39% had detectable levels of ochratoxin A, and 11% had concentrations greater than 0.5 ng/ml. These studies demonstrate that ochratoxin A is present in the blood of people in Canada and that two possible points of entry of this toxin into the human food chain are contaminated grain and pork products.

Animal Feed↗
PubMed2001

Glove barriers to bacterial cross-contamination between hands to food.

Human hands are an important source of microbial contamination of foods. However, published data on the effectiveness of handwashing and glove use in a foodservice setting are limited. Bacterial transfer through foodservice quality gloves was quantified using nalidixic acid-resistant Enterobacter aerogenes (a nonpathogenic surrogate with attachment characteristics similar to Salmonella). Five transfer rates were determined: chicken to bare hand, chicken to hand through gloves, bare hand to lettuce, hand to lettuce through gloves (with low inoculum on hands), and hand to lettuce through gloves (with high inoculum on hands). At least 30 observations were made for each percent transfer rate using 30 individual volunteers. The logarithm of percent transfer data were then fit to distributions: chicken to bare hand, normal (0.71, 0.42); chicken to hand through gloves, gamma (5.91, 0.40, -5.00); bare hand to lettuce, logistic (1.16, 0.30); hand to lettuce through gloves (low inoculum), normal (0.35, 0.88); hand to lettuce through gloves (high inoculum), normal (-2.52, 0.61). A 0.01% transfer was observed from food to hands and from hands to food when subjects wore gloves and a 10% transfer was observed without a glove barrier. These results indicate that gloves are permeable to bacteria although transfer from hands to food through a glove barrier was less than without a glove barrier. Our results indicate that gloves may reduce both bacterial transfer from food to the hands of foodservice workers and in subsequent transfer from hands back to food.

Colony Count, Microbial↗
PubMed2001

Molecular identification of food-borne and water-borne protozoa.

Cryptosporidium and Giardia can be transmitted to humans by contaminated food and water, resulting in large outbreaks of diarrheal disease. Sensitive methods for detecting these parasites are needed to control and prevent infection. However, this issue is complicated by the fact that there is still uncertainty about the role played by different species/genotypes with respect to human disease. We are in the process of collecting samples from clinical cases (both sporadic and outbreak-related human infections) and from the environment (tap and waste water samples from different geographic regions), to test the efficacy of methods for detection and genotyping. Concerning Cryptosporidium parvum, we have developed new genotyping methods based on highly polymorphic microsatellite markers. The use of microsatellite markers allows the route of transmission to be traced; these methods can also be used not only to distinguish between anthroponotic and zoonotic transmission but also to identify the source(s) of infection. Regarding Giardia, which was found very frequently in environmental water samples, we are testing the beta-giardin gene as a marker to discriminate among species/genotypes.

Animals↗
PubMed1986

[A food-borne infection caused by Campylobacter jejuni serotype Lauwers 19].

Report on a outbreak due to contaminated food involving 556 schoolchildren who got their lunch from a school kitchen. The outbreak occurred abruptly without any secondary infectious. Examinations for Salmonellae, Shigellae, Enteritis-coli, Yersiniae and Rotaviruses were negative. However, Campylobacter jejuni were isolated from 105 specimens of faeces in Rostock. Sixty of these strains and another 2 that had been isolated at the same time but had no relation to the outbreak in Rostock, were further differentiated in Berlin-Buch. All of them proved to be Campylobacter jejuni biotype 2. Serotyping according to Lauwers revealed that 58 out of the 60 strains isolated belong to serotype 19. One of the two remaining strains could not be typed, the other was identified as serotype 1. One of the two cultivated strains that were not related to the outbreak in Rostock, was untypable, the other being of serotype 2. Therefore it can be assumed that the outbreak came from the same source of infection. Epidemiological investigations pointed to some food which had been served 6 days prior to the outbreak. The meal had consisted of white cabbage stew with beef. The kitchen supplies the cooked food to several institutions; 3 different dishes being prepared each day, referred to as dish, A, B and C. The institutions receiving dish A - which on November 1, 1985 was the above-mentioned white cabbage stew - actually included several classes of a school as well as a kindergarten. On that particular day however the kindergarten had not been supplied with dish A but, as an exception, with dish B.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Environmental contaminants in the food chain.

Both terrestrial and aquatic food chains are capable of accumulating certain environmental contaminants to toxic concentrations. This article focuses on the aquatic food chain because we have less control over contaminant entry into this chain than we have for the terrestrial chain. In general, at least three special properties are required for a contaminant to bioaccumulate in an aquatic food chain: 1) a high octanol-water partition coefficient, 2) chemical and metabolic stability in water and in organisms in the food chain, and 3) a low toxicity to organisms in the chain so that the chain is not broken by loss of an intermediate species. Few of the thousands of chemicals produced by human industry meet these requirements. In terms of organic chemicals, the best known examples of bioaccumulation in aquatic food chains are the polychlorinated biphenyls (PCBs), dioxins, and organochlorine pesticides such as dichlorodiphenyltrichloroethane (DDT). Few examples exist of bioaccumulation of metal compounds. Methylmercury is arguably the most dramatic and best documented example of high bioaccumulation.

Animals↗
PubMed1980

Lack of person-to-person transmission of enterotoxigenic Escherichia coli despite close contact.

The scanty epidemiologic evidence available suggests that enterotoxigenic Escherichia coli (ETEC) are usually spread by contaminated food and water vehicles; little is known of the risk of secondary spread by contact transmission. Studies carried out in a 22-bed isolation Ward at the U. of Maryland Hospital gave the opportunity to determine whether individuals excreting ETEC, with and without diarrhea, would transmit the pathogen to controls living in close contact. In one combined study, seven volunteers who had ingested 10(8) virulent ETEC (strain H10407), were housed day and night for two weeks with eight other volunterrs participating in an intranasal attenuated influenza vaccine study. In a second study, four persons ingesting 10(8) ETEC (strain 214-4) lived with 13 who were inoculated with intranasal influenza vaccine. The individuals in the E. coli and influenza groups were randomly mixed in bedrooms and shared bathrooms, dining and recreation areas of the ward. Seven persons who ingested ETEC developed diarrhea; all 11 excreted the pathogen (10(7)-10(9) organisms/gm or ml of stool), and 10 had significant rises in anti-O or antitoxin antibody. In contrast, no influenza vaccinees, despite close sharing of facilities, developed diarrhea, excreted ETEC or had rises in antibody to E. coli antigens. These data suggest that ETEC are not readily transmitted to healthy adults by direct person-to-person contact. Precautions to prevent contamination of shared food sources would appear to be the most rational intervention to avoid secondary cases of ETEC diarrhea.

Adolescent↗
PubMed1991

Listeria in effluents from the food-processing industry.

There is general agreement that listeriosis has a significant impact on Man as well as on animals. Listeria monocytogenes has been isolated from the faeces of healthy human and animal carriers and from various environmental sources. L. monocytogenes is the pathogenic species most responsible for abortion, septicaemia and meningitis in animals and Man. Listeria ivanovii is a primary cause of abortion in animals. Owing to a number of epidemics and single cases caused by food contaminated with L. monocytogenes, listeriosis has received more attention in the past ten years than ever before. Entry of the organism into food-processing plants is primarily caused by animals which excrete Listeria in their faeces. Other sources of entry are raw foods of animal origin and personnel in food establishment. Proliferation of Listeria is promoted by high humidity and nutrient waste in certain food production plants. Removal of Listeria is almost impossible by routine disinfection. Listeria-contaminated sites pose a serious risk of recontamination of food-processing equipment and processed foods. Moreover, such sites represent an inexhaustible source of entry for Listeria in plant effluents. There is no denying that effluents from food-processing plants increase the spread of Listeria in the environment. However, considering the existence of other sources of entry, such as human and animal husbandry wastes, and that circulation and recontamination within the environment itself are also possible, this may not be a particularly important risk.

Animals↗
PubMedDate not supplied

Dietary intake, levels in food and estimated intake of lead, cadmium, and mercury.

Since 1980, systematic efforts have been made by the Joint UNEP/FAO/WHO Food Contamination Monitoring Programme to collect information on dietary intake of various contaminants, exemplified by lead, cadmium and mercury. In 1980-88, average adult intakes of lead varied from 1 to 63 micrograms/kg bw/week, approaching or exceeding the Provisional Tolerate Weekly Intake (PTWI) of 25 micrograms/kg bw in four countries providing data. Major sources in food and drinking water differed from country to country. A downward trend was observed consequent on reduction in use of lead-soldered cans and of lead in petrol. Few countries provided data on intakes by infants and children (more vulnerable groups) but the mean exceeded the PTWI in three countries, heavily influenced by levels in water and lowest in infants consuming only breast milk. Average adult intakes of cadmium were, with one exception, below the PTWI of 7 micrograms/kg bw; intakes by children were higher on a body weight basis but still within the PTWI in countries supplying data. Highest levels occurred in offal (mean 320 micrograms/kg) and shellfish (200 micrograms/kg) but, because of amounts consumed, reduction of concentrations in cereals, roots and tubers would be most effective. Important sources of contamination included phosphate fertilizer sewage sludge, plated/galvanized equipment, enamels and glazes. For mercury, average intakes were below the PTWI (300 micrograms/person; 200 micrograms/person or 3.3 micrograms/kg bw as methylmercury) for adults and for breast-fed infants. Contributions from fish varied from 20 to 85%; in some countries because of different dietary habits, cereals or meat may contribute similar amounts. Because of inadequate data on food other than fish, intake estimates are biassed and sometimes based solely on typical levels in fish.

Adult↗
PubMed2000

Environment and contaminants in traditional food systems of northern indigenous peoples.

Traditional food resources of indigenous peoples are now recognized as containing a variety of environmental contaminants which reach food species through local or long-range transport avenues. In this chapter we review the published reports of contaminants contained in traditional food in northern North America and Europe as organochlorines, heavy metals, and radionuclides. Usually, multiple contaminants are contained in the same food species. Measurement of dietary exposure to these environmental contaminants is reviewed, as are major issues of risk assessment, evaluation, and management. The dilemma faced by indigenous peoples in weighing the multiple nutritional and socioeconomic benefits of traditional food use against risk of contaminants in culturally important food resources is described.

Chlordan↗