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PubMed2001

Growth Rate of the microalga Tetraselmis suecica changes the biochemical composition of Artemia species.

The impact of different microalgal semicontinuous cultures on growth and biochemical composition in the next link of the food chain was tested using the filter feeder Artemia species as a model. The marine microalga Tetraselmis suecica was cultured semicontinuously with renewal rates between 10% and 50% and used to feed Artemia. Microalgal cultures maintained with a low renewal rate that had biochemical composition similar to that of the stationary-phase cultures commonly used in aquaculture produced poor growth and survival and low food-conversion efficiency compared to cultures maintained with a high renewal rate. Changes in the renewal rate in microalgal cultures also resulted in important changes in the gross biochemical composition of the filter feeder. The gross biochemical composition of the Artemia resembled that of the microalgae used as food except for total lipid content. The percentage of protein in the organic fraction of Artemia increased from 45% to 65% of the organic weight with increasing renewal rates in the microalgal cultures, while the carbohydrate percentage decreased under the same conditions. Higher renewal rates resulted in higher lipid percentages in the microalga, but in Artemia the percentage of lipids decreased from 19% of the organic weight with a renewal rate of 10%, to 13% with a renewal rate of 50%. The percentage of all polyunsaturated fatty acids in Artemia, including 20:5n-3, increased slightly with increasing renewal rates in the microalgal cultures. Results emphasize the importance of controlling microalgal nutritional value for the success of aquaculture food chains in which filter feeders are involved.

Journal Article↗
PubMed2004

Epidemiologic studies of PCB congener profiles in North American fish consuming populations.

Long range atmospheric and stream transport and oceanic currents drive the ecologic process of PCB deposition in the abiotic environment. In contrast short range transport via bioaccumulation-biomagnification up the food chain determines PCB congener profiles and concentrations and their adverse effects in biological organisms. Two research approaches to congeners, with potential to associate specific adverse human health effects with PCB concentrations in indigenous small populations, are summarized in this study. The field epidemiological approach includes giving questionnaires to target population groups in conjunction with sampling for PCBs (and selected persistent organic pollutants and metals), in foods purchased or hunted and collected by Inuit peoples. Direct determination of contaminant levels in food sources and among individuals in selected comparative subpopulations is also presented.

Animals↗
PubMed2000

Chronic toxicity of rare-earth elements on human beings: implications of blood biochemical indices in REE-high regions, South Jiangxi.

Blood analyses for rare-earth element (REE)-high background regions in South Jiangxi show that the population averages of many of the biochemical indices deviate markedly from normal values in the normal region. These deviations are thought to be caused by prolonged intake of REE through food chains in view of that the toxicity of other harmful metals such as Pb and Cd can be neglected because of their insignificant amounts in the environment. In comparison with the normal region, blood biochemical indices abnormal in the REE-high regions are manifested as low total serum protein (TSP), albumin, beta-globulin, glutamic pyruvic transitanase, serium triglycerides, and immunoglobulin, but high cholesterol. These deviations may be related to the REE concentration and composition of food chains, and are sex dependent. Certain blood indices (such as TSP) of different age groups in the LREE-high region indicate that the influence of REE on males is a one-way irreversible process, whereas females show a strong ability of restoration.

Adult↗
PubMed2001

Influence of mining-related activities on concentrations of metals in water and sediment from streams of the Black Hills, South Dakota.

Water and sediment samples were collected from streams in Spearfish Creek, Whitewood Creek, and Bear Butte Creek watersheds in the Black Hills, SD, an area impacted by gold mining operations. Arsenic concentrations that exceeded the U.S. Environmental Protection Agency's Maximum Concentration Limit of 50 microg/L for drinking water were found in water from Annie Creek, a tributary of Spearfish Creek, and from Whitewood Creek. Gold Run, a tributary of Whitewood Creek, and Annie Creek contained Se concentrations in water that exceeded the EPA Ecotox threshold of 5 microg/L and were classified as a high hazard for Se accumulation from water into the planktonic food chain and for resultant toxicity to fish and aquatic birds. Concentrations of As, Cd, Cu, Hg, Ni, Pb, and Zn in sediment exceeded EPA Ecotox thresholds in one or more of the watersheds suggesting potential adverse ecological effects. Sediment from Rubicon Creek, a tributary of Spearfish Creek, contained Se concentrations high enough (4.0 microg/g) to be a moderate hazard for accumulation from sediments into the benthic food chain, with resultant dietary toxicity to fish and aquatic birds. These results are discussed in light of historical mining activities and recent clean-up and reclamation efforts. Based on the results and comparisons to Ecotox tresholds, further studies of ecological effects are warranted.

Environmental Monitoring↗
PubMed1995

Risk assessment, life history strategies, and turtles: could declines be prevented or predicted?

The process of ecological risk assessment should involve the ability to predict adverse outcomes of particular environmental contaminants or human intrusions. Ecological risk assessment generally focuses on populations, communities, and ecosystems, rather than on individual health. We explore the importance of life history strategies of aquatic turtles to their risk from environmental contaminants and other human activities using three examples: the wood turtle Clemmys insculpta, a freshwater species; the diamondback terrapin Malaclemys terrapin, a littoral species; and marine turtles as a group. These turtles are partly herbivorous and are at low or intermediate levels on the food chain, yet are particularly vulnerable due to their life history strategies of being long-lived with relatively low survival of young. They suffer a variety of natural mortality factors that include predation, starvation, and disease, as well as inundation and destruction of nesting beaches and their eggs by storms. Yet they also face a number of anthropogenic hazards, including toxic chemicals and floatables (plastics); capture for food, other products, and pets; incidental mortality in fishing gear; disturbance while nesting or moving on land; injuries or death by collision with boats; and increased predator exposure because of humans. The three turtle species (or groups of species) examined have experienced these natural and anthropogenic pressures differentially, with resultant differences in the rates of population declines. Because they are lower on the food chain than other obligate carnivores, they are less vulnerable to toxics, and to date, toxics seem a relatively inconsequential environmental risk to turtles.

Animals↗
PubMed1997

Strategies to control Salmonella and Campylobacter in raw poultry products.

Foodborne illness is a major public health concern. The largest number of foodborne illness cases attributed to poultry and poultry products are caused by paratyphoid serotypes of Salmonella and by Campylobacter jejuni. The effective prevention of foodborne disease requires an understanding that contamination can be introduced into foods at numerous points along the food chain. Since multiple entry points exist for foodborne pathogens, multifaceted intervention approaches are required to successfully control contamination of poultry during the various phases of the growth period and processing procedure of broiler chickens. Strategies during the grow-out period (the period during which day-old chicks are raised to six- to seven-week-old broiler chickens) include sanitation, biosecurity, vaccine and drug therapy, and biological control procedures, such as those aimed at preventing colonisation. There are also many critical control points identified in the processing plant which reduce contamination. These include temperature controls (washer and product), chemical interventions, water replacements and counter-flow technology in the scalder and chiller, and equipment maintenance. Transportation and food handling at retail outlets and by the consumer (i.e., storage at the proper temperature and adequate cooking) are the final critical control points in the farm-to-table continuum. It is important to apply risk reduction strategies throughout the food chain. These include: easing the development and implementation of voluntary animal production 'best management practices', implementing in-plant hazard analysis and critical control point systems, developing effective transportation and refrigeration standards, working to facilitate adoption of the model Food Code in all States and providing educational materials and support for public health activities nationwide.

Animals↗
PubMedDate not supplied

Overview of acrylamide monitoring databases.

Since high acrylamide levels in carbohydrate-rich food were reported in 2002, many research activities were started in order to gain knowledge on occurrence, formation, and prevention of this compound in food products. Among them, monitoring programs were conducted in many countries worldwide by official bodies as well as by the food industry. National and international bodies set up monitoring databases. In 2003, both the European Commission and the World Health Organization posted calls for data and placed their spreadsheets for the submission of data on the Web. The goal of the databases is to collect data for a reliable estimation of the exposure of consumers to acrylamide via the food chain. This paper describes the assessment of the data quality and outlines the composition of the data in the 2 databases, to date.

Acrylamide↗
PubMed2001

Pesticide residues in human food and wildlife in The Netherlands.

Several monitoring programmes for pesticide residues in food are currently operative in the Netherlands, some of which are related to EU directives. These programmes cover a range of products. This paper reviews the 1997 and 1998 data for fruit and vegetables, meat, milk, livestock and fish, as well as presenting data on pesticide residues in wildlife. The aim of the paper is to provide an overview of what is known about pesticide residues in the Netherlands, including indications of the origins of the compounds found. A total of 281 different compounds were monitored on fruit and vegetables. Of these compounds, 45% were actually found on products and 28% exceeded the standard. Expressed as percentages of the number of measurements, the data show that 0.3% of the measurements detected a compound, and standards were exceeded in 0.02% of the measurements. Some of the cases in which standards were exceeded concerned the use of compounds in minor crops, for which their use is not permitted. Other cases involved excessive dosages or application within the safety interval before harvest. In meat, milk and livestock, 10 persistent organochlorine compounds were measured. Most of these compounds, with the exception of lindane, are no longer in use, but are still being found as residues. The concentrations found were very low and have not exceeded standards for human consumption since 1993. No assessment was made, however, of products currently in use. Organochlorine compounds have also frequently been found in fish (eel), in higher concentrations than in meat, but in nearly all cases in quantities below the standards for human consumption. Ecological standards for accumulation in the food chain were exceeded on a larger scale and indications of exposure effects on piscivorous birds (cormorants) were found. No data on pesticide residues in wildlife are known for terrestrial organisms.

Animals↗
PubMed2003

Identification and enumeration of Fusarium species in poultry feed mixtures from Slovakia.

Thirty-three samples of poultry mixed feeds collected in the region of Nitra (Slovakia) from August 2001-April 2002 were assayed for the incidence of Fusarium Link: Fr. species. In tested samples, the total frequency of isolated fusaria was determined to be 48 % (16 samples) and their counts ranged from 0.2 x 10(2) to 2.4 x 10( 4 ) CFU per g of the sample on Dichloran Chloramphenicol Peptone Agar (DCPA). Of the total amount of Fusarium isolates (609), the highest part (i.e. 584 isolates) was represented by Fusarium proliferatum (Matsushima) Nirenberg, being isolated in all the samples tested. Fusarium subglutinans (Wollenw. et Reinking) Nelson, Tousson et Marasas (in total 24 isolates) was found in 3 positive samples (9%) and Fusarium oxysporum Schlecht. Fr. (a single isolate) was found in one positive sample only (3%). Data of these significant mycotoxin producers found in examined samples with particular mycotoxins as well as their habitats were summarised briefly. The results refer to a large incidence of the potentially toxinogenic Fusarium species, mainly F. proliferatum, in the feeds of Slovakian origin which represent entry components of the food chain. The study also points out a potential risk of feed contamination with hazardous toxic compounds, especially by carcinogenic fumonisins and cardiotoxic moniliformin. From the hygienic point of view, it will be necessary to continue monitoring and evaluating this occurrence.

Animal Feed↗
PubMed1994

Bioavailability of metals and arsenic to small mammals at a mining waste-contaminated wetland.

In support of a baseline ecological risk assessment evaluating the impacts of mining wastes at the Milltown Reservoir Sediments Superfund site in Montana, a food chain transfer analysis was performed for resident small mammals. Deer mice (Peromyscus maniculatus) and meadow voles (Microtus pennsylvanicus) were trapped from a 200 A portion of a mixed upland and palustrine wetland, and concentrations of As, Cd, Cu, Pb, and Zn in carcass, liver, kidney, and testes were quantified. Concurrent to small mammal trapping, samples of grasses, forbs, and soils were collected and analyzed for metal and As residues. Using a linear multimedia food-chain model, assuming a forage base of wetland vegetation from the site, ingestion of local surface water, and incidental ingestion of soils with vegetation, body burdens of the metals and As in the herbivores were estimated. As a means of estimating potential element bioavailability at the site, the modeled body burdens were compared with measured element concentrations in herbivore tissues. The analysis indicates that the bioavailabilities of As, Cd, Cu, Pb, and Zn were equal to or less than 0.2% for internal organs and 0.1% for carcasses, on a microgram/g tissue wet weight basis. Available site data on soil pH, cation exchange capacity, and extractable elements fraction supported the limited release of soil elements. These results suggest that the bioavailable fraction of mining waste metals in riparian wetland soils may be quite small, and, for the Milltown Reservoir site, lower than originally anticipated.

Animals↗
PubMed2004

Drainage basin security of hazardous chemical fluxe in the Yodo River basin.

The Yodo River basin consists of three major tributary basins (and other small river basins) namely Uji, Katsura and Kizu, which overlap respectively Shiga, Kvoto and Nara prefectures' administrative areas. Lake Biwa, the largest lake in Japan, drains water through the Uji river. The water quality of the lake, in terms of BOD, continuously improved over the last decade. However, the quality in terms of COD did not show any improvement in spite of a large amount of infrastructure finance being introduced. Eutrophication of the lake still continues, showing no improvement in the nitrogen concentration level. Non-point as well as point source control is not strong enough. There is a gap between BOD and COD evaluations of the lake water quality. Hazardous chemical fluxes are estimated based upon PRTR reports of Japan (2001). PCBs are still discharged into the lake, although the report of Shiga Prefecture showed zero discharge. Dace fish monitoring clearly showed that PCB contamination of the fish had not changed since the 1980s in spite of a ban on use and production of PCBs in the 1970s. There is still leakage of PCBs into the lake. The major exposure of dioxins to Japanese is fish rather than meat and eggs. The risk of water contamination must take into consideration not only drinking water safety but also ecological magnification of food chains in water. The ecological health aspect of hazardous chemicals is also important, such as organotins with imposex of sea snails. Finally, public participation in hazardous chemical management is very important using the method of risk communication based upon the annual report of PRTR in Japan.

Animals↗
PubMed2005

Conceptual approaches for the development of dynamic specific activity models of 14C transfer from surface water to humans.

Carbon-14 is a particularly interesting radionuclide from the perspective of dose estimation. Many nuclear facilities, including power reactors, release 14C into the environment, and much of this is as 14CO2. This mixes readily with stable CO2, and hence enters the food chain as fundamental biomolecules. This isotopic mixing is often used as the basis for dose assessment models. The present model was developed for the situation of 14C releases to surface waters, where there are distinct changes in the water 14C activity concentrations throughout the year. Complete isotopic mixing (equilibrium) cannot be assumed. The model computes the specific activity (activity of 14C per mass of total C) in water, phytoplankton, fish, crops, meat, milk and air, following a typical irrigation-based food-chain scenario. For most of the biotic compartments, the specific activity is a function of the specific activity in the previous time step, the specific activity of the substrate media, and the C turnover rate in the tissue. The turnover rate is taken to include biochemical turnover, growth dilution and mortality, recognizing that it is turnover of C in the population, not a tissue or an individual, that is relevant. Attention is paid to the incorporation of 14C into the surface water biota and the loss of any remaining 14CO2 from the surface water-air interface under its own activity concentration gradient. For certain pathways, variants in the conceptual model are presented, in order to fully discuss the possibilities. As an example, a new model of the soil-to-plant specific activity relationship is proposed, where the degassing of both 14C and stable C from the soil is considered. Selection of parameter values to represent the turnover rates as modeled is important, and is dealt with in a companion paper.

Air Pollution, Radioactive↗
PubMed2006

Vancomycin- and erythromycin-resistant enterococci in a pig farm and its environment.

A high prevalence of vancomycin- and erythromycin-resistant enterococci (VRE and ERE respectively) in a pig farm and its environment was observed. A similar structure and composition of enterococcal populations was detected between urban sewage and those associated with the pig environment. Enterococcus faecium was the most predominant species among VRE isolates from both animal and human origin. The high population similarity index (Sp) obtained comparing VRE and ERE isolates from urban sewage and pig slurry suggests that there are certain strains circulating through the food chain from farms to humans. Erythromycin resistance was present in a wider variety of clones and species of enterococci in both pigs and humans than vancomycin resistance.

Animal Feed↗
PubMedDate not supplied

Chemical immobilization of lead, zinc, and cadmium in smelter-contaminated soils using biosolids and rock phosphate.

Chemical immobilization, an in situ remediation method where inexpensive chemicals are used to reduce contaminant solubility in contaminated soil, has gained attention. We investigated the effectiveness of lime-stabilized biosolid (LSB), N-Viro Soil (NV), rock phosphate (RP), and anaerobic biosolid (AB) to reduce extractability and plant and gastrointestinal (GI) bioavailability in three Cd-, Pb-, and Zn-contaminated soils from smelter sites. Treated (100 g kg(-1) soil) and control soils were incubated at 27 degrees C and -0.033 MPa (0.33 bar) water content for 90 d. The effect of soil treatment on metal extractability was evaluated by sequential extraction, on phytoavailability by a lettuce bioassay (Lactuca sativa L.), on human GI availability of Pb from soil ingestion by the Physiologically Based Extraction Test. The largest reductions in metal extractability and phytoavailability were from alkaline organic treatments (LSB and NV). Phytotoxic Zn [1188 mg Zn kg(-1) extracted with 0.5 M Ca(NO3)2] in Blackwell soil (disturbed soil) was reduced by LSB, NV, and RP to 166, 25, and 784 mg Zn kg(-1), respectively. Rock phosphate was the only treatment that reduced GI-available Pb in both gastric and intestinal solutions, 23 and 92%, respectively. Alkaline organic treatments (LSB, NV) decreases Cd transmission through the food chain pathway, whereas rock phosphate decreases risk from exposure to Pb via the soil ingestion pathway. Alkaline organic treatments can reduce human exposure to Cd and Pb by reducing Zn phytotoxicity and revegetation of contaminated sites.

Biological Availability↗
PubMed2001

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↗
PubMed2006

Antibiotic-resistant Campylobacter: could efflux pump inhibitors control infection?

Campylobacter is the most common cause of bacterial gastroenteritis in the world. Poultry is the main reservoir of human infections. The widespread use of antibiotics in agriculture and veterinary medicine has resulted in the emergence of an increasing number of antibiotic-resistant Campylobacter strains that can be transmitted to humans through the food chain. Of particular concern to public health is the prevalence of resistance to macrolides and fluoroquinolones that are used in the treatment of life-threatening campylobacteriosis. The CmeABC efflux system has been shown to contribute to the intrinsic and acquired resistance to these antibiotics. In addition, by mediating resistance to bile, it is essential for colonization of the chicken gut in vivo. Inhibition of CmeABC may provide an effective means of reversing antibiotic resistance and decreasing the transmission of Campylobacter via the food chain. This would positively impact on public health by decreasing the morbidity, mortality and increased healthcare costs associated with the treatment of antibiotic-resistant Campylobacter.

ATP Binding Cassette Transporter, Subfamily B↗
PubMedDate not supplied

Environmental risk factors of cancer and their primary prevention.

The evaluation of the influence of different environmental carcinogenic factors requires interdisciplinary cooperation. Related studies include epidemiological surveys and air, water and soil, chemical, toxicological, and microbiological analyses, supplemented by experimental verification of suspected ecological pathogens and cofactors. A balance of carcinogens and protective agents in the external environment and in the human body is recommended for an ecologically oriented prevention. Toxicological control of the food chain using modern technology (Proton-induced X-ray emission (PIXE), nuclear activation analysis, and induced coupled plasma) should be integrated with microanalyses at the cellular level (by X-ray scanning electron microscopy, nuclear magnetic response, PIXE, and spontaneous and delayed chemiluminescence for balance of free-radicals and their scavengers). A pilot cross-disciplinary study conducted in the area of a "cluster" of human neoplasms and cattle leukemia, in comparison with control villages in Poland, showed an excess in Pb, Hg, Ni, Rb, K, Mn, Cr, and Zn, accompanied by a nutritional deficiency in Mg, Ca, Fe, Co, and Se in the food chain of the "cluster." The living and breeding houses in this area were significantly more contaminated with the toxicogenic molds Aspergillus flavus and Penicillium meleagrinum and by nitrate and nitrite in the drinking water. Our experiments showed that selenium deficiency stimulated the growth of fungi and some bacteria and increased the immunosuppressive and teratogenic effects of aflatoxin B1. New methods of protection of the indoor environment against microbiological contamination and laser-related biotechnology for nutritional prevention of selenium deficiency and associated risk of neoplasms have been introduced. Primary prevention requires a large scale application of highly sensitive methods for early detection of risk factors in the environment, food, water, and at the personal level, as well as education of the society and an integrated common corrective action.

Air Pollution↗
PubMedDate not supplied

Distribution of polybrominated biphenyls (PBB) among fractions derived from contaminated human plasma.

The introduction of polybrominated biphenyls (PBB) into the Michigan food chain resulted in the presence of low levels of PBB in plasma pools used for blood fractionation. Pooled plasma lots contained an average of 1.0 +/- 0.2 ng/ml of PBB, while antihemophilic factor, fibrinogen, and immune serum globulin did not contain detectable amounts of PBB. Albumin (25%) lots contained an average of 2.0 +/- 0.4 ng/ml of PBB. Analysis of old lots showed that PBB first appeared in an albumin lot filled in January, 1974. Plasma used in preparing this lot was drawn during the period when PBB was entering the food chain. The results indicated that the behavior of chemical pollutants is an important consideration when fractionating blood or plasma collected in areas where industrial or environmental pollution have occurred.

Animal Feed↗