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PubMed1968

DDT residues and declining reproduction in the Bermuda petrel.

Residues of DDT [1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane] averaging 6.44 parts per million in eggs and chicks of the carnivorous Bermuda petrel indicate widespread contamination of an oceanic food chain that is remote from applications of DDT. Reproduction by the petrel has declined during the last 10 years at the annual rate of 3.25 percent; if the decline continues, reproduction will fail completely by 1978. Concentrations of residues are similar to those in certain terrestrial carnivorous birds whose productivity is also declining. Various considerations implicate contamination by insecticides as a probable major cause of the decline.

Animals↗
PubMed1991

Caesium concentration factors in wild herbivores and the fox (Vulpes vulpes L).

A selection of wild animals was sampled in the winter of 1986/87. The sites chosen for sampling were based on information obtained from survey carried out by The Institute of Terrestrial Ecology in the spring and autumn of 1986. Animals included deer, grouse, hares and rabbits, and foxes which were collected as a top carnivore in the food chain. Variation in concentration of caesium between species from the same area was unpredictable; rabbits, for instance, never exceeded 200 Bq kg(-1) (fresh wt) of (137)Cs in their flesh, even when adjacent to deer forests with over 1000 Bq kg(-1) in the venison. The greatest complication grose from areas of peaty uplands where the pre-Chernobyl (137)Cs from weapons-testing was much higher than expected. This pre-Chernobyl contribution amounted to 630 Bq kg(-1) in a red grouse from the Pennines, and 650 Bq kg(-1) in a roe deer from near the Borders, being c. 60% of the total. Concentration factors were calculated using values from freshly ingested vegetation and tissues from individual animals. Significant differences in concentration factors were found depending on species, food, sex, breeding condition and age. Contrasting the decrease of the two caesium isotopes in roe deer from forestry on peat with those from woodlands on mineral soils, it appeared that after an initial fall in concentration, the only decrease thereafter occurred on the mineral soils. Nowhere were radiocaesium concentrations high enough to cause concern amongst consumers of game and other wild animals, even when levels exceed 3000 Bq kg(-1) (fresh wt) as they did in red deer, red grouse and the blue hare.

Journal Article↗
PubMed2003

Time trends of persistent organic pollutants and heavy metals in umbilical cord blood of Inuit infants born in Nunavik (Québec, Canada) between 1994 and 2001.

Inuit inhabitants of Nunavik (northern Québec, Canada) consume great quantities of marine food and are therefore exposed to high doses of food chain contaminants. In this study, we report the time trends of persistent organic pollutants, mercury, and lead in umbilical cord blood of infants from three communities of the east coast of Hudson Bay in Nunavik. We analyzed 251 cord blood samples collected from 1994 through 2001 for polychlorinated biphenyls (PCBs), dichlorodiphenyl trichloroethane (DDT), dichlorodiphenyl dichloroethylene (DDE), hexachlorobenzene (HCB), chlordanes, lead, and mercury. Using an exponential model, we found strongly significant decreasing trends for PCBs (7.9% per year, p < 0.001), DDE (9.1% per year, p < 0.001), DDT (8.2% per year, p < 0.001), and HCB (6.6% per year, p < 0.01). No significant trends were detected for chlordanes. A significant reduction of lead and mercury concentrations was found, but there was no clear linear or exponential trend. The decreases observed could be explained by a decrease in food contamination, by changes in dietary habits, or, most likely, by a combination of both.

Adult↗
PubMedDate not supplied

Ochratoxin a: its cancer risk and potential for exposure.

Ochratoxin A (OA) is a naturally occurring mycotoxin known to contaminate a variety of foods and beverages. The cancer risk posed by OA was reviewed as relevant to human exposure, regulatory activities, and risk management efforts occurring worldwide, particularly in Europe. OA moves through the food chain and has been found in the tissues and organs of animals, including human blood and breast milk. Results from the National Toxicology Program's rodent bioassays show significantly increased incidence of mammary gland tumors in female rats and kidney tumors in male and female rats given OA orally. Liver tumors in female mice fed OA in the diet have also been observed. In humans, OA exposure has been most often associated with the kidney disease Balkan endemic nephropathy (BEN), symptoms of which include tumors of the kidney and urinary tract. No epidemiological studies have yet adequately evaluated the cancer risk of OA in human populations. Studies have shown OA to be genotoxic as well as immunotoxic, although its mode of action is not fully understood. Organizations and agencies in many countries are currently promulgating standards for OA in foods and beverages. Increased efforts in farm management and food safety are being made to mitigate the risks to public health posed by OA. The U.S. Food and Drug Administration (FDA) is currently evaluating data on OA levels in domestic and imported commodities but has not established official regulations or guidelines for OA in the U.S. food supply.

Aspergillus ochraceus↗
PubMed1989

[Bean grain quality].

As the title states, the present document is a review of the factors which may influence the bean grain quality. This quality is determined by factors such as acceptability by the consumer, cooking characteristics and by its nutritive value. At the same time, these factors are affected by the genetic constitution of the grain as well as by the environmental conditions of production. Therefore, the improvement obtained on the bean-grain quality will be measured through the interaction established among the different disciplines, such as geneticists, agronomists and scientists in food science and nutrition. The above-mentioned factors are influenced by the events that occur in the different links of the food chain. This article analyzes the effect of processing on the nutritive quality of the grain and, likewise, a brief review of the hard-to-cook problem which affects the acceptability of the grain by the consumer is made. It also considers the low protein digestibility problem and the effects that have been associated to tannin content, as well as the carbohydrate utilization. Finally, some recommendations are suggested to improve the nutritional quality of beans, which is the most important protein source for large segments of the worldwide population.

Digestion↗
PubMed2006

[Chemical and effect-related analysis of dioxins and dioxinlike PCB's].

Dioxins and dioxinlike PCBs are high toxic and persistent compounds. They accumulate in the feed and food chain. Because of their occurrence in a very low concentration range, the established requirements for analytical methods are restrictive. Commission Directive 2002/69/EC of 26 July 2002 lays down sampling methods and methods of analysis for the official control of dioxins and dioxinlike PCBs in foodstuff. Confirmatory methods are high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS). Screening methods could be used to select samples with significant levels of dioxins. Bioassay--for example the EROD-Bioassay--can be used as a screening method.

Animal Feed↗
PubMed1992

Concept of seasonality in the light of the Chernobyl accident.

Seasonality could have a strong influence on the radiological impact of environmental radioactive contamination. Short-lived radionuclides (e.g., 131l) and those that mainly enter the food chain by direct contamination (e.g., 137Cs) are especially important in this context. In particular, the contamination of cereals is influenced by seasonality. For temperate latitudes it is generally true that radioactive contamination during winter, when the fields lie fallow and the domestic animals are stabled, will result in a significantly lower radiological impact than if a similar contamination were to take place in the summer shortly before harvesting. The impact of the Chernobyl accident on the radioactive contamination of human diet was strongly influenced by seasonality.

Accidents↗
PubMed2000

[Food contamination by PCBs/dioxins in Belgium: analysis of an accident with improbable health consequences].

In 1999, a food crisis broke out in Belgium as a result of the accidental contamination of animal feed by PCBs (polychlorobiphenyls) and dioxins (mainly furans). The analysis of the database from the PCB food monitoring program implemented after the discovery of incident confirms that the contamination has been very limited, both in time (peak at the end of January) and in the food chain (affecting less than 0.5% of the farms in the whole country). The extreme scenario of a doubling of the PCB and dioxin body burden as envisaged in "Nature" (401: 231-232, 1999) could have been conceivable only in the case of farmers who would have consumed their own products. But even in such an extreme case, this would mean going back to the levels of PCB and dioxin body burden of subjects living in the 1980s or of those regularly eating contaminated seafood.

Accidents↗
PubMedDate not supplied

Surface plasmon resonance biosensors for detection of pathogenic microorganisms: strategies to secure food and environmental safety.

This review describes the exploitation of exclusively optical surface plasmon resonance (SPR) biosensors for the direct and indirect detection of pathogenic microorganisms in food chains and the environment. Direct detection is, in most cases, facilitated by the use of defined monoclonal or polyclonal antibodies raised against (a part of) the target pathogenic microorganisms. The antibodies were immobilized to a solid phase of the sensor to capture the microbe from the sample. Alternatively, antibodies were used in an inhibition-like assay involving incubation with the target organism prior to analysis of nonbound antibodies. The free immunoglobins were screened on a sensor surface coated with either purified antigens or with Fc or Fab binding antibodies. Discussed examples of these approaches are the determination of Escherichia coli O1 57:H7, Salmonella spp., and Listeria monocytogenes. Another direct detection strategy involved SPR analysis of polymerase chain reaction products of Shiga toxin-2 genes reporting the presence of E. coli O157:H7 in human stool. Metabolic products have been exploited as biomarkers for the presence of a microbial agent, such as enterotoxin B and a virulence factor for the occurrence of Staphylococcus aureus and Streptococcus suis, respectively. Indirect detection, on the other hand, is performed by analysis of a humoral immune response of the infected animal or human. By immobilization of specific antigenic structures, infections with Herpes simplex and human immunodeficiency viruses, Salmonella and Treponema pallidum bacteria, and Schistosoma spp. parasites were revealed using human, avian, and porcine sera and avian eggs. Bound antibodies were easily isotyped using an SPR biosensor to reveal the infection history of the individual. Discussed studies show the recent recognition of the suitability of this type of instrument for (rapid) detection of health-threatening microbes to food and environmental microbial safety.

Biosensing Techniques↗
PubMed2002

[The risk of variant Creutzfeldt-Jakob disease in the Netherlands and the effect of preventive measures].

Variant Creutzfeldt-Jakob disease (vCJD) is a fatal and untreatable neurological disease, in which pathogenic prions (PrPSc) are involved. There is convincing epidemiological and experimental evidence that vCJD is a human expression of bovine spongiform encephalopathy (BSE). The risk of transmission of pathogenic prions which cause vCJD to humans is influenced by the species barrier, genetic susceptibility of the host, dose of infection and route of exposure. Transmission of pathogenic prions from bovines to humans is possible through meat products containing nerve and lymphatic tissue, and through medical products derived from bovine material. Human to human transmission is, in principle, also possible via blood and blood-derived products, human organs and tissues for transplantation, and through surgical instruments. Preventive measures to reduce transmission from bovines to humans have been introduced step by step in the Netherlands since 1989. With proper implementation, the current risk of becoming infected by Dutch meat products is small. It is very likely, however, that in the past decade BSE-infected bovines have entered the food chain. The Dutch population has also been exposed to foreign infected meat products. Measures to prevent human to human transmission are currently being improved in the Netherlands. It is expected that cases of vCJD will occur in the Netherlands in the future, but the number cannot be estimated accurately. The presence of PrPSc in both the livestock and in the human population in the Netherlands constitutes a permanent public health threat and is a reason for continued vigilance and active prevention.

Animals↗
PubMed2005

Metals in Nile perch (Lates niloticus) and suspended particulate matter from Lake Victoria, Tanzania.

A study was conducted to assess the levels of pollutant metals in suspended particulate matter and Nile perch from Lake Victoria. The metals in particulate matter were determined to ascertain their concentrations at the base of the food chain. Nile perch samples were collected in September 2003 from five major fish processing factories at the shores of Lake Victoria in Mwanza and Musoma. The concentrations of total Hg, Pb, Cd, and Cu were generally low in particulate matter and in most locations were close to or below their limits of detection. The concentrations of Zn were high in suspended particulate matter, the highest being 219.4 +/- 153.0 microg L(-1) found in particulate matter from Nungwe Bay in the southern part of Lake Victoria. Nile perch generally contained low levels of heavy metals; the range for Pb was <0.01-0.08 microg g(-1) ww, Cd was <0.001-0.04 microg g(-1) ww, Cu was 0.01-0.97 microg g(-1) ww, and Zn was <0.01-18.94 microg g(-1) ww. The concentration of total mercury ranged between 31.0 and 684.2 ng g(-1) ww; generally, it was below the Food and Agriculture Organization of the United Nations/World Health Organization (1000 ng total Hg g(-1) ww for piscivorous fish species) maximum allowable level. Indeed, all Nile perch samples that weighed less than 10 kg had less than 200 ng total Hg g(-1) ww and therefore are safe for regular consumption by at-risk groups such as children and pregnant women. Levels of mercury and other heavy metals in Nile perch at present is, therefore, not a severe environmental issue; however, urgent regulatory measures should be taken to minimize metal input into the lake to maintain the current levels in the fish.

Animals↗
PubMedDate not supplied

Evaluation of 137Cs activity in plant drugs and in some phytoderivatives from Chernobyl accident up to present (1986-1994).

The accident to the nuclear power plant of Chernobyl (in April 1986) caused a radioactive contamination in large areas of the majority of European countries. During the first transient time the fall-out phenomenon was the most important method of contamination, particularly from 131I whose relative isotopic abundance with respect to other released radionuclides was very high. Thereafter, 137Cs, owing to its long half-time and its large presence in environmental matrixes and so in the food chain, became the element on which the attention was to be focused. Plant drugs and their derivatives are, at present, of very large alimentary consumption among people. This can cause some problems to human health, so the authors have studied (from 1986 to 1994) the activity of 137Cs in a large number of drugs (about 5000) and in some industrial and home-made officinal products. Some suggestions on the Cs+,K+ ions competition in soil can also be derived.

Cesium Radioisotopes↗
PubMed2001

Possible health impact of phytoestrogens and xenoestrogens in food.

Plants produce estrogen-like substances, denominated phytoestrogens, which are present in many human foodstuffs. The consumption of phytoestrogens has been associated with a variety of protective effects. Their relative estrogenic potency combined with their concentrations in food and human plasma indicate biological relevance. However, their biological properties differ from those of estradiol or other endogenous estrogens in humans. For instance, their possible effects on SHBG, inhibition of steroid metabolizing enzymes, anti-proliferative and anti-angiogenetic and other side effects have been described. Furthermore, phytoestrogens can exert estrogenic and antiestrogenic activities at the same time and their potency and metabolism have not been yet elucidated in all cases. In recent decades growing evidence has accumulated on the hormone-like effects of synthetic chemicals that appeared in the environment. The possible impact of xenoestrogens, to which humans are also exposed through the food chain, needs to be further clarified as well. The molecular effects and control mechanisms of these substances, their pharmacokinetics, threshold levels and dose-response differences are issues that require further research before a full assessment of their effect on humans can be drawn. Evaluating the total exposure and impact of this estrogenic effect is very challenging because of the lack of specific knowledge in some areas and the differences in the biological activity among these substances, as pinpointed in this review.

Animals↗
PubMed2003

Comparison of dioxin and PCB concentrations in human breast milk samples from Hong Kong and the Netherlands.

The adverse effects of dioxins and polychlorinated biphenyls (PCBs) on human health are of increasing concern. These lipophilic compounds are concentrated through the food chain and are present in human milk. This study compares PCB levels in human milk samples from Hong Kong and Dutch mothers. Ten breast milk samples from Hong Kong and 10 from the Netherlands were collected during home visits between 2 and 6 weeks postpartum. Total toxic equivalence (TEQ) of dioxin and PCBs were determined using the DR-CALUX(R) bioassay. The total dioxin and PCB levels in breast milk samples for Hong Kong ranged from 3.1 to 29.9 pg TEQ g(-1) lipid and for the Netherlands from 8.9 to 89.5 pg TEQ g(-1) lipid. Despite Hong Kong's high degree of industrialization, the levels of dioxin and PCBs were fourfold lower in the Hong Kong than in the Dutch samples. This may be due to a lower dietary intake of dioxins and PCBs in Hong Kong because of lower background levels of these contaminants or to different food habits.

Adult↗
PubMed1997

Ecosystem recovery following selenium contamination in a freshwater reservoir.

Belews Lake, North Carolina, was contaminated by selenium in wastewater released from a coal-fired electric generating facility during 1974-1985. Selenium bioaccumulated in aquatic food chains and caused severe reproductive failure and teratogenic deformities in fish. Beginning in 1986, the electric utility company changed its ash disposal practices and selenium-laden wastewater no longer entered the lake. A survey of selenium present in the water, sediments, benthic invertebrates, fish, and aquatic birds was conducted in 1996. Concentrations were compared to pre-1986 levels to determine how much change occurred during the decade since selenium inputs stopped. The data were also examined using a hazard assessment protocol to determine if ecosystem-level hazards to fish and aquatic birds had changed as well. Results reveal that waterborne selenium fell from a peak of 20 micrograms/liter before 1986, to < 1 microgram/liter in 1996; concentrations in biota were 85-95% lower in 1996. Hazard ratings indicate that high hazard existed prior to 1986 and that moderate hazard is still present, primarily due to selenium in the sediment-detrital food pathway. Concentrations of selenium in sediments have fallen by about 65-75%, but remain sufficiently elevated (1-4 micrograms/g) to contaminate benthic food organisms of fish and aquatic birds. Field evidence confirmed the validity of the hazard ratings. Developmental abnormalities in young fish indicate that selenium-induced teratogenesis and reproductive impairment are occurring. Moreover, the concentrations of selenium in benthic food organisms are sufficient to cause mortality in young bluegill and other centrarchids because of Winter Stress Syndrome. At the ecosystem level, recovery has been slow. Toxic effects are still evident 10 years after selenium inputs were stopped. The sediment-associated selenium will likely continue to be a significant hazard to fish and aquatic birds for years.

Animals↗
PubMed1992

Ciguatoxic fish in the French West Indies.

An epidemiological study on ciguatera fish poisoning in the French West Indies on St-Barthelemy, St-Martin and Anguilla was conducted in the years 1985-1986-1987 and 1991-1992. A study on the toxicity of coral fish was realized. The toxicity of 700 fish belonging to 57 species was evaluated by bio-assays. 430 mosquito-bio-assays were performed on individual fish (flesh or liver) and 19 on pools (flesh or liver; with 4 to 24 fish). A second group was evaluated on liver by the chick feeding-test (33 individual and 64 on pools with 2 to 24 fish). The results showed that many species are involved in the toxic food chain. At least 25% may have a high level of toxicity, 32.5% are intermediate and 10% are doubtful. Major results concern: (1) high risk species (Caranx bartholomaei, C. lugubris, Lutjanus apodus, L. jocu, Gymnothorax funebris, G. moringa, Mycteroperca venenosa, M. tigris, Epinephelus morio, Sphyraena barracuda); (2) intermediate species (Caranx latus, C. ruber, Lutjanus buccanella); (3) low risk species (Balistes vetula, Haemulon album, Priacantus arenatus, Alphestes afer). Occasionally other species or new species are involved Etelis oculatus, Lutjanus analis, Pristipomoides macrophtalmus, Rhomboplites aurorubens, Haemulon album, Scarus vetula.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1997

Health impacts of large releases of radionuclides. Physical transport and chemical and biological processes in agricultural systems.

The purpose of radioecological models is to make realistic estimates of doses to the public after accidental releases of radionuclides into the environment. Important physical, chemical and biological processes involved in the dispersion and transport of radioactive substances in the atmosphere and along the food-chains are presented. The results of the EURAD (EURopean Acid Deposition) model, predicting the deposition patterns of 131I and 137Cs in Belarus and Ukraine after the Chernobyl accident, are discussed. An overview of the most important ecological processes--such as deposition, interception and translocation, weathering, transfers from soil to plants and from plants to animal/animal products, and seasonality in agricultural environments--is given. Examples corresponding to these individual processes, mainly experimental results after the Chernobyl accident and related to radiocaesium and radioiodine, are shown and discussed.

Agriculture↗
PubMed2005

Trace elements analysis in forage samples from a US Navy bombing range (Vieques, Puerto Rico).

Plants are good environmental sensors of the soil conditions in which they are growing. They also respond directly to the state of air. The tops of plants are collectors of air pollutants, and their chemical composition may be a good indicator for contaminated-areas when it is assessed against background values obtained for unpolluted vegetation. Both, aquatic and terrestrial plants are known to bioaccumulate heavy metals and therefore represent a potential source of these contaminants to the human food chain. An evaluation of heavy metals was conducted from vegetation samples collected at the Atlantic Fleet Weapons Training Facilities (AFWTF) in Vieques, Puerto Rico. In order to understand the potential risks associated to heavy metal mobilization through biological systems, it is first necessary to establish background values obtained from reference locations. This information allows a better interpretation of the significance of anthropogenic factors in changing trace elements status in soil and plants. Since Guánica State Forest is located at a similar geoclimatic zone as the AFWTF, samples at this site were used as a standard reference material and as experimental controls. Both sampling and analysis were conducted as previously described in standardized protocols using acid digestion of dry ashes. Then, levels of heavy metals were obtained by air-acetylene flame detection in an atomic absorption spectrophotometer. Our results from the samples taken at the AFWTF indicate mobilization of undesirable trace elements through the marine and terrestrial food web. Since plants naturally remove heavy metals from soils, they could be employed for the restoration of this and similarly contaminated sites.

Environmental Monitoring↗