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Results 401 - 450 of 631
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Sarma S S - - 2001
We compared the population growth of B. calyciflorus and B. patulus using the green alga Chlorella vulgaris, baker's yeast Saccharomyces cerevisiae or their mixture in equal proportions as food. Food was offered once every 24 h in two concentrations (low: 1 x 10(6) and high: 3 x 10(6) cells ml-1) ...
Tenke C E - - 2001
Dense electrode arrays offer numerous advantages over single channel electroencephalogram/event-related potential (EEG/ERP) recordings, but also exaggerate the influence of common error sources arising from the preparation of scalp placements. Even with conventional low density recordings (e.g. 30-channel Electro-Cap), over-application of electrode gel may result in electrolyte leakage and create low ...
Matta M B - - 2001
This research determined the potential for methylmercury or Aroclor 1268 to disrupt reproduction and sexual differentiation in Fundulus heteroclitus. The research determined whether fish that are exposed to mercury or Aroclor 1268 survive and successfully reproduce; whether offspring of exposed fish hatch, survive, produce eggs, and fertilize them; and whether ...
Vucetich L M - - 2001
We used deer mice (Peromyscus maniculatus) to investigate variation in mercury exposure across the terrestrial ecosystem of Isle Royale National Park (Michigan, USA). Although previous work suggested that mercury (Hg) levels may be higher inside the Sargent Lake watershed of Isle Royale than outside the watershed, Hg concentrations in livers ...
O'Shea T J - - 2001
Rocky Mountain Arsenal (RMA) National Wildlife Area, near Denver, Colorado, is a Superfund site contaminated by past military and industrial uses, including pesticide manufacturing. From an ecosystem standpoint, the most critical contaminants at RMA are certain cyclodiene insecticides and metabolites, p,p'-DDE, p,p'-DDT, arsenic, and mercury. Bats are important ecosystem components ...
Goutner V - - 2001
We studied the relationships between mercury content of Squacco Heron (Ardeola ralloides) chick body-feathers and nestling age, hatching order (seniors-juniors) and growth parameters, and the date of feather sampling in the Axios Delta, northern Greece, in 1993 (n = 75 chicks) and 1994 (n = 80). Mercury levels were not ...
Hepp N M - - 2001
A procedure using an automated microwave flow digestion technique was developed and validated for the digestion of samples of certifiable color additives before mercury determination by cold vapor atomic absorption spectrometry. Recovery studies were performed by spiking most of the color additives subject to batch certification by the U.S. Food ...
Vasjari M - - 2000
A simple technique for the calibration of mercury vapor chemosensors is described. It is based on a reductive deposition of a well-defined quantity of mercury (0) onto gold wire followed by thermal evaporation of the mercury into the sensor cell. The quantity of mercury on the gold wire was measured ...
Cok I - - 2000
Smokeless tobacco is used in various forms in some countries of the world. "Maraş otu" is a kind of smokeless tobacco usage in the Southeastern region of Turkey. The use of smokeless tobacco causes nicotine addiction and dependence. Moreover this type of smokeless tobacco usage is one of the risk ...
Podczeck F - - 2000
Granulated powdered cellulose was studied in terms of powder bulk properties and capsule filling performance on a tamp-filling machine with and without the addition of various concentrations of magnesium stearate. Carr's compressibility reached its minimum value at 0.4% magnesium stearate suggesting an improvement of powder flow compared to the unlubricated ...
Duvall S E - - 2000
A screening level probabilistic assessment of risks was performed on three species of piscivorous wildlife at the top of Everglades aquatic food webs: the American alligator (Alligator mississippiensis), the great egret (Egretta alba), and the raccoon (Procyon lotor varius). Ranges of dietary exposure concentrations (and probability distribution functions) were derived ...
Falnoga I - - 2000
Total Hg and Se concentrations were determined in autopsy samples of retired Idrija mercury mine workers, Idrija residents living in a Hg-contaminated environment, and a control group with no known Hg exposure from the environment. In selected samples we also checked the presence of MeHg. The highest Hg concentrations were ...
Redmayne A C - - 2000
This research focuses on mercury (Hg) bioaccumulation in New Zealand long-tinned eels (Anguilla dieffenbachii) from the aquatic environment. Total Hg (HgT) and methyl mercury (MeHg) concentrations were determined in muscle tissue from eels living in three South Island rivers dominated respectively by urban, native bush and agricultural land-uses. Most of ...
Santa Rosa R - - 2000
Gold extraction and its commercialization in the Amazon region is mainly by rudimentary procedures. Therefore, during the process of extraction and recovery of this precious metal, large amounts of mercury vapors are thrown into the environment. This paper is an attempt to establish a correlation between the concentration of total ...
Hylander L D - - 2000
The tropical flood plain Pantanal is one of the world's largest wetlands and a wildlife sanctuary. Mercury (Hg) emissions from some upstream gold mining areas and recent findings of high natural Hg levels in tropical oxisols motivated studies on the Hg cycle in the Pantanal. A survey was made on ...
Ye K - - 2000
Determining the depth to which continental lithosphere can be subducted into the mantle at convergent plate boundaries is of importance for understanding the long-term growth of supercontinents as well as the dynamic processes that shape such margins. Recent discoveries of coesite and diamond in regional ultrahigh-pressure (UHP) metamorphic rocks has ...
Lee Y H - - 2000
Previous studies at the Svartberget catchment in northern Sweden have identified potential terrestrial sources of methylmercury (MeHg) and total mercury (THg) in runoff as well as processes controlling MeHg/Hg transfers from soil to runoff water. This paper considers whether the concepts based on a few seasons of observations are consistent ...
Maurice-Bourgoin L - - 2000
In this paper, the results of mercury concentrations in two abiotic compartments (river water and suspended particles) and two biotic compartments (fish and human hair) from the upper Madeira rivers of the Bolivian Amazon basin are presented. Because of the local hydrological regimes and a high deposition rate in the ...
Akagi H - - 2000
Artisanal gold-mining activities in the Philippines have proliferated since the early 1980s. Presently, environmental and health monitoring conducted by several governmental agencies is limited to the determination of total mercury only. Previous studies undertaken focused mainly on the exposure of adults and workers to mercury during mining/processing operations. However, in ...
van Straaten P - - 2000
In northern Tanzania large numbers of small scale miners use mercury in the gold extraction process causing contamination of the environment and risks to human health. Human exposure to Hg was assessed in populations in and around small scale gold mining camps by means of human hair and urine surveys. ...
Chan H M - - 2000
Traditional food of indigenous people in Canada, particularly fish and marine mammal meat, has mercury (Hg) concentrations exceeding the Canadian consumption guideline level of 0.5 microg/g. Health effects of Hg in traditional food are, therefore, a concern. We conducted contaminant exposure assessments in 28 indigenous communities in Canada. Hg exposure ...
Ohmoto K - - 2000
This study examined the relationship between mercury content and mercury evaporation from amalgams during setting. Two different types of commercial high-copper amalgams (single composition and admixed types) were used. Cylindrical specimens of each amalgam were prepared with five different mercury contents according to ADA Specification No.1. Specimens were also prepared ...
O'Brien D L - - 2000
OBJECTIVE: To assess the accuracy of an oral predictive thermometer and an infrared emission detection (IRED) tympanic thermometer in detecting fever in an adult emergency department (ED) population, using an oral glass mercury thermometer as the criterion standard. METHODS: This was a single-center, nonrandomized trial performed in the ED of ...
Westermarck S - - 2000
The effect of pretreatment and scanning speed of mercury porosimetry on the porosity result of microcrystalline cellulose tablets was studied. The porosity parameters followed were total pore volume, mean and median pore size, and volume pore size distribution. Scanning speed did not affect the total pore volume of tablets compressed ...
Goutner V - - 2000
Feathers of Audouin's gull chicks from three Aegean island areas (north Dodecanese, Cyclades, Kythera) Greece, were sampled in 1997 and 1998 and analyzed for mercury. Mean concentrations varied from 0. 94 microg/g (Lipsos, Dodecanese, 1998) to 2.14 microg/g (Paros, Cyclades, 1998). Significant differences between years occurred in some regions (Lipsos, ...
Marins R V - - 2000
A system, based on annular gold-coated denuders, was optimized and used in the atmospheric sampling of mercury in urban and rural sites of the Alta Floresta, a region in the Brazilian Amazon. Results showed that vapour phase mercury (Hgv) is dominant in samples collected in both sites. However, particulate mercury ...
Biles P V - - 2000
Under Section 402(a)(3) of the Food, Drug and Cosmetic Act the distribution of foods which may contain repulsive or offensive matter, considered as filth, is prohibited. Filth includes contaminants such as rat, mouse, and other animal hairs and excreta; whole insects, insect parts, and excreta; and other extraneous materials which, ...
Oliveira Ribeiro C A - - 2000
This paper reports comparative results on the bioaccumulation of inorganic mercury and resulting gill damages in the tropical fish, Trichomycterus zonatus, and a nordic species, Salvelinus alpinus, using radioisotope 203Hg techniques and scanning electron microscopy. Uptake of inorganic Hg from water was much more important in T. zonatus than in ...
Boischio A A - - 2000
Mercury pollution (MeHg) up the aquatic food chains in the Amazonian ecosystems has been a major concern in environmental health. Riverside people (ribeirinhos) along the Upper Madeira river are heavy fish eaters. Hair is the best biomarker for MeHg exposure. By assuming a constant hair growth rate, it is possible ...
Boyd A S - - 2000
Human contact with mercury has been ongoing for centuries and was previously considered a legitimate means of treating different cutaneous and systemic conditions. Toxicity from this heavy metal may occur from exposure to elemental, inorganic, and organic forms of mercury. This article outlines the signs and symptoms of mercury poisoning ...
Carro A M - - 2000
Trace metals such as mercury, especially its organic compounds, are an important risk to the environment and to man due to their accumulation in the food chain. For this reason, the routine determination of the very toxic methylmercury, and of other organic and inorganic mercury compounds in marine and land ...
Dubey J P - - 2000
Serum samples from 973 ostriches (Struthio camelus) in Canada were examined for antibodies to Toxoplasma gondii by the modified agglutination test incorporating mercaptoethanol and formalin-fixed whole tachyzoites. Twenty-eight (2.9%) of the 973 birds were found to be seropositive for antibodies to T. gondii at titers of 1:25 in 15 birds, ...
Crinnion W J - - 2000
Mercury is ubiquitous in the environment, and in our mouths in the form of "silver" amalgams. Once introduced to the body through food or vapor, mercury is rapidly absorbed and accumulates in several tissues, leading to increased oxidative damage, mitochondrial dysfunction, and cell death. Mercury primarily affects neurological tissue, resulting ...
Hansen J C - - 2000
Monitoring of human exposure to persistent organic pollutants POPs and heavy metals have taken place since 1994 in a circumpolar study conducted under the Arctic monitoring and assessment programme (AMAP). The study has confirmed that Arctic populations relying on marine food (Inuit) have an exposure level of POPs and methyl ...
Larter N C - - 2000
Aluminum, nickel, cadmium, mercury and lead levels were measured in the kidney tissue of Banks Island Peary caribou and barren-ground caribou, from the Bluenose herd, of the western Northwest Territories of Canada. Cadmium concentrations of Bluenose caribou were similar to those reported elsewhere for barren-ground caribou and showed a positive ...
Bellanger T M - - 2000
The primary source of non-occupational exposure to mercury is through the consumption of contaminated fish. Since 1994, the Louisiana Department of Environmental Quality has reported mercury contamination in fish obtained from bodies of water throughout the state and has issued fish consumption advisories accordingly. To determine the extent of mercury ...
Alonso J - - 2000
The levels of mercury in terrestrial ecosystems are generally very low, but the strong accumulation in some species of macrofungi is an exception from this rule. Mercury contents of 41 samples of edible mushrooms fruiting bodies representing eight species (six wild and two cultivated) were determined by an anodic stripping ...
Riget F - - 2000
Mercury concentrations were determined in muscle tissue of lake resident and anadromous populations of Arctic char in Greenland. Mercury in lake sediment, and in soil and humus from the surrounding area were also determined in the main localities. Fish length and dry weight were shown to be important covariables, which ...
Johansen P - - 2000
The human intake of lead, cadmium, mercury and selenium from local Greenlandic marine food was estimated based on dietary studies and contaminant information. The average lead intake was calculated to be 15 micrograms/person per week, which is very low, whereas the intake of cadmium and mercury was estimated to be ...
Riget F - - 2000
Lead, cadmium, mercury and selenium levels in the Greenland marine environment from the first phase of the AMAP are presented. Samples were collected in 1994-1995 covering four widely separated regions in Greenland. Samples included sediments, soft tissue of blue mussel; and liver of polar cod, shorthorn sculpin, glaucous gull, Iceland ...
Thieme D - - 2000
Lists of banned classes of doping agents are released by the International Olympic Committee, adopted by other sports authorities and updated regularly, including the substance classes stimulants, narcotics, diuretics, anabolic agents, peptide hormones, beta-blockers etc. There are different classes of restriction: anabolic and masking agents (anabolic steroids, diuretics etc.) are ...
Ishihara N - - 2000
Fecal excretion of methyl mercury was confirmed in four Japanese male subjects. Perhaps the methyl mercury detected in feces is dependent on (a) the unabsorbed methyl mercury in diet, (b) exfoliation of intestinal cells, (c) hepatic bile, and (d) intestinal methylation of inorganic mercury. The calculated amounts of methyl mercury ...
Lee W C - - 1999
Relationships have been established between the mercury (Hg) levels in human scalp hair and environmental or dietary mercury exposures. The average value of total mercury (THg) in scalp hair of male residents in Seoul city was 1.66 +/- 1.10 ppm (+/- SD) and for methylmercury (MeHg) was 1.02 +/- 0.72 ...
Bosnir J - - 1999
AIM: To compare the total and organic mercury content in sea-fish samples from Croatia, where fishing occurs in a closed part of the Mediterranean Sea, and from other countries fishing mostly in the oceans. METHOD: During 1997, we collected at the Zagreb fish market a total of 115 samples of ...
Nichols J - - 1999
A procedure has been developed to estimate surface water concentrations of toxicants ("wildlife values") that will protect the viability of wildlife populations associated with aquatic resources. This procedure was designed primarily to protect piscivorous birds and mammals from compounds that bioaccumulate in fish and was used in the Great Lakes ...
Deppisch L M LM Department of Pathology, Northeastern Ohio Universities College of Medicine, Rootstown, USA. - - 1999
Historians have suggested that US president Andrew Jackson (1767-1845) experienced lead and mercury poisoning following his therapeutic use of calomel (mercurous chloride) and sugar of lead (lead acetate). To evaluate these claims, we performed direct physical measurement of 2 samples of Jackson's hair (1 from 1815, 1 from 1839). Following ...
Pergent G - - 1999
Mercury levels in the marine phanerogam Posidonia oceanica were evaluated at three sites subjected to different environmental conditions (anthropogenic activity). Mercury uptake by primary production varied from 9.9 to 100.6 microg m(-2) year(-1). For the entire Mediterranean basin, nearly one ton of mercury is mobilized each year, that is to ...
Bodaly R A - - 1999
We studied the uptake of mercury (Hg) by finescale dace (Phoxinus neogaeus) in an experimental boreal reservoir for 2 years prior to flooding and 3 years after flooding, and in a natural wetland pond over the same 5-year period. Hg uptake was much higher after flooding as compared to uptake ...
Storelli M M - - 1999
In the framework of a wide monitoring programme on the presence of heavy metals in marine organisms caught in the South Adriatic Sea, cadmium and total mercury concentrations were determined in flesh and hepatopancreas of 512 specimens of two species of cephalopods. The aim of the study was to establish ...
Fiedler N - - 1999
Residents of a former factory building converted to apartments were exposed to mercury over a 2-year period. The neurobehavioral and emotional health effects of this exposure and subsequent evacuation are presented. Urine mercury levels were measured before (urine1) and 3-10 weeks after evacuation (urine2) of the building, when neurobehavioral and ...
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