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PubMed1998

Points of view: Inuit women's perceptions of pollution.

Inuit women's perceptions of health risks from potential contamination in the arctic food chain were investigated in 1995 through in-depth interviews with 47 women in a Canadian arctic community. This number represents 34% of the eligible participants in the population of the research community. Many of these Inuit women suggest that pollution can appear in a variety of forms, from drug and alcohol consumption to visible air and water contaminants to possible invisible contaminants in arctic wildlife. Concepts of pollution--starting with the individual body and extending to the body politic--are influenced by a complex of sociocultural factors arising from historical and contemporary community life.

Attitude to Health↗
PubMed2005

Heavy metal and Pb isotopic compositions of aquatic organisms in the Pearl River Estuary, South China.

The accumulation of trace metals in aquatic organisms may lead to serious health problems through the food chain. The present research project aims to study the accumulation and potential sources of trace metals in aquatic organisms of the Pearl River Estuary (PRE). Four groups of aquatic organisms, including fish, crab, shrimp, and shellfish, were collected in the PRE for trace metal and Pb isotopic analyses. The trace metal concentrations in the aquatic organism samples ranged from 0.01 to 2.10 mg/kg Cd, 0.02 to 4.33 mg/kg Co, 0.08 to 4.27 mg/kg Cr, 0.15 to 77.8 mg/kg Cu, 0.17 to 31.0 mg/kg Ni, 0.04 to 30.7 mg/kg Pb, and 8.78 to 86.3 mg/kg Zn (wet weight). High concentrations of Cd were found in crab, shrimp and shellfish samples, while high concentration of Pb was found in fish. In comparison with the baseline reference values in other parts of the world, fish in the PRE had the highest elevated trace metals. The results of Pb isotopic compositions indicated that the bioaccumulation of Pb in fish come from a wide variety of food sources and/or exposure pathways, particularly the anthropogenic inputs.

Animals↗
PubMedDate not supplied

Assessment of health risks from fallout radiocesium in a hunting and food-gathering society.

Hunting and food-gathering societies are particularly vulnerable to the effects of fallout, since these people are often at the head of natural food chains which can bioaccumulate toxic substances. This paper describes a study on the effects of fallout radiocesium in caribou consumers of northern Canada. Portable whole body counting equipment was transported into five Arctic communities in 1989-90 and used to measure radiocesium body burdens in over 1100 people. The results were compared with a similar survey carried out in 1967-68. The mean body burden for adults in each community had decreased by a factor of 20 to 30 since the earlier survey. It was possible to derive an effective half time of about 4.5 years for the decrease of Cs-137 body burdens in the Arctic. The mean lifetime dose from the ingestion of radiocesium since 1967 amounted to not more than 12 mSv, with possibly an equal contribution from the period before 1967. The current radiation doses are much less than natural background and it is possible to reassure northern residents that caribou meat remains a safe and nutritious food source.

Adolescent↗
PubMed1999

An outbreak of multidrug-resistant, quinolone-resistant Salmonella enterica serotype typhimurium DT104.

BACKGROUND: Food-borne salmonella infections have become a major problem in industrialized countries. The strain of Salmonella enterica serotype typhimurium known as definitive phage type 104 (DT104) is usually resistant to five drugs: ampicillin, chloramphenicol, streptomycin, sulfonamides, and tetracycline. An increasing proportion of DT104 isolates also have reduced susceptibility to fluoroquinolones. METHODS: The Danish salmonella surveillance program determines the phage types of all typhimurium strains from the food chain, and in the case of suspected outbreaks, five-drug-resistant strains are characterized by molecular methods. All patients infected with five-drug-resistant typhimurium are interviewed to obtain clinical and epidemiologic data. In 1998, an outbreak of salmonella occurred, in which the strain of typhimurium DT104 was new to Denmark. We investigated this outbreak and report here our findings. RESULTS: Until 1997, DT104 infections made up less than 1 percent of all human salmonella infections. The strain isolated from patients in the first community outbreak of DT104 in Denmark, in 1998 was resistant to nalidixic acid and had reduced susceptibility to fluoroquinolones. The outbreak included 25 culture-confirmed cases. Eleven patients were hospitalized, and two died. The molecular epidemiology and data from patients indicated that the primary source was a Danish swine herd. Furthermore, the investigation suggested reduced clinical effectiveness of treatment with fluoroquinolones. CONCLUSIONS: Our investigation of an outbreak of DT104 documented the spread of quinolone-resistant bacteria from food animals to humans; this spread was associated with infections that were difficult to treat. Because of the increase in quinolone resistance in salmonella, the use of fluoroquinolones in food animals should be restricted.

Abattoirs↗
PubMed2006

Concentrations and partitioning of polychlorinated biphenyls in the surface waters of the southern Baltic Sea-seasonal effects.

In the marine environment, the partitioning of hydrophobic organic contaminants, such as polychlorinated biphenyls (PCBs), between the dissolved and suspended matter phases in the water column plays a fundamental role in determining contaminant fate (e.g., air-water exchange or food-chain uptake). Despite the pronounced seasonality in physical, chemical, and biological conditions in temperate marine ecosystems, little is known about the seasonality in organic contaminant partitioning behavior. Surface water from the western Baltic Sea was sampled regularly during an 18-month period between February 2003 and July 2004. The concentrations of seven PCB congeners were determined in the dissolved and particulate organic carbon (POC) phases. An inverse relationship was found between K(POC) (i.e., the ratio between the POC-normalized PCB concentration [pg/kg POC] and the dissolved concentration [pg/L]) and temperature. The decrease in the water temperature of 20 degrees C between summer and winter resulted in an increase in K(POC) by a factor of approximately five. The POC-normalized PCB concentrations were higher in winter than in summer by a factor of 9 to 20. This reflected the higher K(POC) and somewhat greater PCB concentrations in the dissolved phase, and it could have consequences for bioaccumulation of these chemicals in aquatic food webs. The results demonstrate a clear seasonality in contaminant partitioning in the temperate marine environment that should be accounted for when interpreting field data or modeling contaminant fate.

Polychlorinated Biphenyls↗
PubMed2002

Economic changes imposed by mycotoxins in food grains: case study of deoxynivalenol in winter wheat.

The Fusarium epidemic of 1996 in Ontario winter wheat resulted in direct losses of well over $100 million Canadian dollars (CDN). More importantly, wheat marketing in Ontario has changed. The market focus remains primarily food grade. Thus, the awareness of deoxynivalenol (DON) entering the food chain has influenced marketing and trade. New market tolerances for DON have been set. The Chicago Board of Trade will only accept up to 5 ppm (DON), while a new tolerance of 0.5 ppm DON has been set in the breakfast cereal markets. Advance contracts are avoided and there is a new reluctance to service export customers, all because of the liability associated with DON. Furthermore, there are no markets for process by-products which contain concentrated levels of DON. Before 1996, DON problems were handled largely by blending grain across the province. A reluctance to blend DON contaminated wheat and site specific sourcing of grain is growing.

Food Contamination↗
PubMed1995

Public health assessment for dioxins exposure from soil.

Dioxins are among the most toxic anthropogenic chemicals in the environment. Their toxicity has been extensively studied in both humans and animals. Dioxin-contaminated soil may result in dioxins occurring in a food chain. This is especially important for the general population. It has been estimated that about 98% of exposure to dioxins is through the oral route. In the 1980s, a concentration level of 1 ppb 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in soil was specified as "a level of concern," based on cancer effects. However, recent studies indicate that end points other than cancer are also of concern. A health risk analysis scenario based on health effects of TCDD other than cancer is discussed and compared with the projected intake from 1 ppb TCDD in soil.

Biological Availability↗
PubMed1994

Organochlorines and mercury in pilot whale blubber consumed by Faroe islanders.

Some 22,000 pilot whales (Globicephala melaena) were taken in the Faroe Islands between 1970 and 1992. It is known that tissues from these animals are widely consumed by the islanders. The position of these animals at the apex of a direct marine food chain renders them liable to accumulate toxic chemicals, such as metals and organochlorines. Although the consumption of contaminating metals in pilot whale tissues has been studied, the significance of blubber as a dietary source of organochlorine compounds has not been fully considered. This study reports levels of organochlorine and mercury contamination in the blubber of pilot whales taken in two Faroese kills. Published estimates of pilot whale tissue consumption are used to evaluate dietary organochlorine intake in relation to established national and international guidelines and clinical studies conducted in the North American Great Lakes.

Adipose Tissue↗
PubMed2005

Elevated levels of cadmium and zinc in paddy soils and elevated levels of cadmium in rice grain downstream of a zinc mineralized area in Thailand: implications for public health.

Prolonged consumption of rice containing elevated cadmium (Cd) levels is a significant health issue particularly in subsistence communities that are dependent on rice produced on-farm. This situation is further exacerbated in areas of known non-ferrous mineralization adjacent to rice-based agricultural systems where the opportunity for contamination of rice and its eventual entry into the food chain is high. In the current study, an assessment of the degree of soil Cd and Zn contamination and associated rice grain Cd contamination downstream of an actively mined zone of Zn mineralization in western Thailand was undertaken. Total soil Cd and Zn concentrations in the rice-based agricultural system investigated ranged from 0.5 to 284 mg kg(-1) and 100 to 8036 mg kg(-1), respectively. Further, the results indicate that the contamination is associated with suspended sediment transported to fields via the irrigation supply. Consequently, the spatial distribution of Cd and Zn is directly related to a field's proximity to primary outlets from in-field irrigation channels and inter-field irrigation flows with 60-100% of the Cd and Zn loading associated with the first three fields in irrigation sequence. Rice grain Cd concentrations in the 524 fields sampled, ranged from 0.05 to 7.7 mg kg(-1). Over 90% of the rice grain samples collected contained Cd at concentrations exceeding the Codex Committee on Food Additives and Contaminants (CCFAC) draft Maximum Permissible Level for rice grain of 0.2 mg Cd kg(-1). In addition, as a function of demographic group, estimated Weekly Intake (WI) values ranged from 20 to 82 mug Cd per kg Body. This poses a significant public health risk to local communities. The results of this study suggest that an irrigation sequence-based field classification technique in combination with strategic soil and rice grain sampling and the estimation of WI values via rice intake alone may be a useful decision support tool to rapidly evaluate potential public health risks in irrigated rice-based agricultural systems receiving Cd contaminated irrigation water. In addition, the proposed technique will facilitate the cost effective strategic targeting of detailed epidemiological studies thus focusing resources to specific 'high risk' areas.

Agriculture↗
PubMed1978

Breast-milk monitoring to measure Michigan's contamination with polybrominated biphenyls.

In 1973 and 1974, several thousand Michigan dairy farms were contaminated by polybrominated biphenyls (P.B.B.) as the result of an industrial accident. An unknown quantity of contaminated meat and dairy products entered the food chain before contaminated farms were quarantined. To determine the extent of human exposure, P.B.B. concentrations were measured in human breast milk, which was collected in a random-sample survey from nursing mothers throughout Michigan. 96% of 53 samples from Michigan's lower peninsula and 43% of 42 samples from the less densely populated upper peninsula contained detectable levels of P.B.B. These data indicate that about 8 million of Michigan's 9.1 million residents have detectable body burdens of P.B.B.

Accidents, Occupational↗
PubMed2005

Prevention of ochratoxin A in commodities and likely effects of processing fractionation and animal feeds.

Whenever possible, preventing the formation of ochratoxin A (OTA) in susceptible food commodities such as cereals, grapes and coffee beans should be the primary aim. Each product tends to host a specific OTA-producing mould so that the environmental conditions and factors that encourage the subsequent formation of OTA need to be understood. Codes of Practice for prevention and management of OTA are being developed and can be used in conjunction with a HACCP approach to protect the end consumer, in line with EU statutory limits. If prevention fails, an understanding of how concentrations change during the whole food chain may be useful in minimizing the concentrations reaching the consumer. OTA is quite heat stable under neutral conditions but may be partly broken down, e.g. in extrusion processing. In milling or other separation procedures, OTA will be concentrated or reduced in the resulting components. By-products such as 'cleanings' or bran may contain high concentrations and are often used for animal feed. Introduction of guideline or statutory maximum concentrations for feed within the EU makes it essential that concentrations of ochratoxin A in such by-products are acceptable. This paper reviews recent literature and findings from recent 5th Framework EU-funded projects.

Animal Feed↗
PubMed1995

Preliminary results of fasting on the kinetics of organochlorines in polar bears (Ursus maritimus).

We determined concentrations of polychlorinated biphenyls (PCBs), chlordanes (CHLORs), chlorobenzenes (CBzs), hexachlorocyclohexanes (HCHs), and dichlorodiphenyltrichloroethane (DDT) and its metabolites (DDD and DDE) in the tissues of individual polar bears (Ursus maritimus) before and after a lengthy period of fasting. Polar bears are an ideal model for such studies. They undergo one of the most extreme fasts known for any mammal and are located at the top of a long food chain, thus biomagnification of organochlorines (OC) is significant. Adipose tissue and milk were collected from different reproductive classes of adult females (solitary/pregnant, with cubs-of-the-year, with yearling cubs) and were analyzed for organochlorine content. As the fasting period progressed and adipose reserves decreased, concentrations of some organochlorines in the adipose tissue and milk increased on a lipid weight basis. The transfer of contaminants from mothers to offspring thus also increases with duration of the fasting period. This phenomenon could adversely influence the survival and growth of cubs during the critical early phase of their development.

Adipose Tissue↗
PubMedDate not supplied

Spread of resistant bacteria and resistance genes from animals to humans--the public health consequences.

The paper reviews the lines of evidence which link the use of antimicrobial drugs for food animals with the emergence of antimicrobial drug resistance in bacteria pathogenic to humans, with a particular focus on the public health aspects. Deductions from the epidemiology of food-borne infections, ecological studies, outbreak investigations, typing studies and direct epidemiological observations show that resistant bacteria are transferred from food animals to man. In addition to transfer in the food chain, exchange of mobile genetic elements among commensal and pathogenic bacteria contributes to the emergence of drug resistance. There is growing evidence that this has measurable consequences for human public health. One consequence is increased transmission supported by unrelated use of anti-microbials in humans. Other consequences are related to reduced efficacy of early empirical treatment, limitations in the choices for treatment after confirmed microbiological diagnosis, and finally a possible coselection of virulence traits. Recent epidemiological studies have measured these consequences in terms of excess mortality associated with resistance, increased duration of illness, and increased risk of invasive illness or hospitalization following infections with resistant Salmonella.

Animals↗
PubMed2004

Allermatch, a webtool for the prediction of potential allergenicity according to current FAO/WHO Codex alimentarius guidelines.

BACKGROUND: Novel proteins entering the food chain, for example by genetic modification of plants, have to be tested for allergenicity. Allermatch http://allermatch.org is a webtool for the efficient and standardized prediction of potential allergenicity of proteins and peptides according to the current recommendations of the FAO/WHO Expert Consultation, as outlined in the Codex alimentarius. DESCRIPTION: A query amino acid sequence is compared with all known allergenic proteins retrieved from the protein databases using a sliding window approach. This identifies stretches of 80 amino acids with more than 35% similarity or small identical stretches of at least six amino acids. The outcome of the analysis is presented in a concise format. The predictive performance of the FAO/WHO criteria is evaluated by screening sets of allergens and non-allergens against the Allermatch databases. Besides correct predictions, both methods are shown to generate false positive and false negative hits and the outcomes should therefore be combined with other methods of allergenicity assessment, as advised by the FAO/WHO. CONCLUSIONS: Allermatch provides an accessible, efficient, and useful webtool for analysis of potential allergenicity of proteins introduced in genetically modified food prior to market release that complies with current FAO/WHO guidelines.

Allergens↗
PubMed1982

[Arsenic emission and effects on the biosphere].

In the GDR, the arsenic emission in the surroundings of metallurgical plants have been reduced to a minimum, the contamination of the soil being not yet diminished in some cases. In the framework of a comprehensive research program, it was shown that the uptake of arsenic by man via the food chain is possible in the area of activity of an arsenic emitter (due to increased arsenic content in the sedimentary dust), even if the maximum emission concentration of arsenic in the aerosol is considerably lower than the permanent limit value. Apart from local sources of emission (e.g. non-ferrous smelteries and phosphate works), the extended burden on the air by traces of arsenic originating from power station exhalates deserves increasing attention. In regions where industrial plants are concentrated, but also in regions with intensive agriculture and horticulture, it is recommendable to determine regularly the arsenic contents in the air, soil, vegetable feeding stuffs and vegetable foodstuffs.

Air Pollutants↗
PubMed1994

The microbiology of minimally processed fresh fruits and vegetables.

Minimally processed fresh (MPF) fruits and vegetables are good media for growth of microorganisms. They have been involved in outbreaks because of the consumption of products contaminated by pathogens. They are also sensitive to various spoilage microorganisms such as pectinolytic bacteria, saprophytic Gram-negative bacteria, lactic acid bacteria, and yeasts. Contamination of MPF fruits and vegetables occurs at every stage of the food chain, from cultivation to processing. Polluted environments during cultivation or poor hygienic conditions in processing increase the risk of contamination with foodborne pathogens. Although MPF fruits and vegetables may harbor psychrotrophic microorganisms such as fluorescent pseudomonads or Listeria monocytogenes, good control of refrigeration temperature limits growth of spoilage and pathogenic microorganisms. Modified atmospheres are often efficient to maintain or improve visual organoleptic quality of MPF fruits and vegetables, but their effects on microorganisms are inconsistent. Chemical disinfection can partially reduce the initial bacterial contamination; irradiation seems to be more efficient. The applications of legislations and quality assurance systems to control contamination, survival, and growth of foodborne pathogens in MPF fruits and vegetables are discussed.

Food Contamination↗
PubMed1983

Impact of cadmium in the environment of the Federal Republic of Germany.

Under present conditions, a further increase of environmental pollution due to cadmium must be expected. The resulting effects would be seen particularly in an increase of cadmium concentration in the food chain and would lead to a higher average intake of cadmium by man. This means that the relatively small percentage of the population who are now exposed to the risk of renal malfunction due to cadmium would increase significantly. The subsequent decontamination of an area once it has been polluted is not possible according to our present knowledge. The consequences could include considerable limitation of land use for agriculture. It must, therefore, be considered essential to undertake preventative measures in order to limit the further output of cadmium to a minimum. To achieve this there are many possibilities in the field of reduction and prevention technology, possibilities which are worth examining and considering individually.

Air Pollutants, Occupational↗
PubMed2003

Exposure assessment of environmental organic chemicals at contaminated sites: a multicompartment modelling approach.

For the prevention of future damages from chemicals at large contaminated sites, all transfer pathways leading to the exposure of man and vulnerable ecosystems have to be taken into account. For organic contaminants, the uptake into vegetation is the major entry route for the transfer into the food chains. Lipophilic substances are taken up by roots but are not translocated with the transpiration stream. Atmospheric background concentrations have a significant impact on foliage contamination due to the effective gaseous and particle deposition. Vegetables can also be contaminated after irrigation with contaminated water supplied by groundwater wells. By means of a multicompartment model, the various uptake processes into roots and foliage as well as the transformation and translocation processes are described and the concentration pattern resulting from daily irrigation with methyl-t-butyl ether in the edible parts is simulated. The results demonstrate the advantage of a dynamic multicompartment model over the static environmental quality standard approach in terms of derivation of possible exposure reduction measures for organic chemicals.

Food Contamination↗