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Results 301 - 350 of 590
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Bostick Benjamin C - - 2004
Arsenic, a toxic metalloid, is commonly associated with sulfide minerals in anoxic sediments. Here we characterize arsenic(III) retention on sediments from a sulfidic estuarine marsh using a series of sorption experiments, and probe the structure of retained arsenite with X-ray absorption spectroscopy. Although the extent of sorption varied with sampling ...
LoPachin Richard M - - 2004
Acrylamide (ACR) is a water-soluble, vinyl monomer that has multiple chemical and industrial applications: e.g., waste water management, ore processing. In addition, ACR is used extensively in molecular laboratories for gel chromatography and is present in certain foods that have been prepared at very high temperatures. Extensive studies in rodents ...
Tillman P Glynn - - 2004
Susceptibility of the brown stink bug, Euschistus serous (Say), and the spined soldier bug, Podisus maculiventris (Say), to acetamiprid, cyfluthrin, dicrotophos, indoxacarb, oxamyl, and thiamethoxam, was compared in residual and oral toxicity tests. Generally, susceptibility of P. maculiventris to insecticides was significantly greater than or not significantly different from that ...
Koul Opender - - 2004
Head space volatiles, including 73% di-n-propyl disulfide, were collected from freshly crushed neem seeds. This compound along with previously reported diallyl disulfide (di-2-propenyl disulfide) were toxic when applied topically or as a fumigant to Tribolium castaneum adults and 8-, 12-, and 16-d-old larvae, and Sitophilus oryzae adults. Di-n-propyl disulfide significantly ...
Montagnolli W - - 2004
Toxic blooms of the cyanobacterium Microcystis aeruginosa, a microcystin producer, have been observed in the past two decades in the Patos Lagoon estuary (southern Brazil). This cyanobacterium reaches the estuary from northern waters and accumulates as toxic blooms in the shallow margins of the environment. Microcystins are phosphatase (PP1 and ...
Das H K - - 2004
Arsenic contaminating groundwater in Bangladesh is one of the largest environmental health hazards in the world. Because of the potential risk to human health through consumption of agricultural produce grown in fields irrigated with arsenic contaminated water, we have determined the level of contamination in 100 samples of crop, vegetables ...
Chen Celia Y - - 2004
As part of a multiple-tier research program, interactions of the herbicide Vision (glyphosate) with two stressors, pH and food level, were examined. Effects of the formulated product Vision were tested at two test concentrations (0.75 and 1.50 mg acid equivalent/L), two pH levels (pH 5.5 and 7.5), and under high ...
Allen Tanu - - 2004
The biochemical toxicity of arsenic trioxide (AsIII) in a freshwater edible fish Channa punctatus has been studied on exposures ranging from 7 to 90 d. The arsenic concentration increased exponentially in liver, kidney, gills, and muscles of fish up to 60 d of exposure to arsenic. However, arsenic concentration in ...
Ranmuthugala Geetha - - 2004
The authors assessed the contribution of food irrigated with arsenic-contaminated water to human exposure to arsenic in Bangladesh. An intervention trial was conducted in a village in the Jessore District of Bangladesh, where irrigation water had been field-tested in March 2000 and was found to contain arsenic with concentrations ranging ...
Díaz Oscar Pablo - - 2004
Total and inorganic As contents of cooked vegetables obtained from an arsenic endemic area of Chile were analyzed. Inorganic As intake from those foods, bread, and water was estimated. The study was performed in two different periods, in which the water used by the population for drinking and cooking purposes ...
Diaz-Somoano Mercedes - - 2004
Volatile arsenic and selenium compounds present in coals may cause environmental problems during coal combustion and gasification. A possible way to avoid such problems may be the use of solid sorbents capable of retaining these elements from flue gases in gas cleaning systems. Lime and limestone are materials that are ...
Ibrahim Sanaa A - - 2004
Toxicity and behavioral effects of nootkatone and two of its derivatives, 1,10-dihydronootkatone and tetrahydronootkatone, to Coptotermes formosanus Shiraki were investigated on workers from two different colonies by using topical application assays, repellency assays, and sand barrier assays. The acute toxicity of the nootkatones on workers from both colonies increased as ...
Shim Joong Sup - - 2004
A homoisoflavanone, 5,7-dihydroxy-3-(3-hydroxy-4-methoxybenzyl)-6-methoxychroman-4-one ( 1), was isolated from the bulb of Cremastra appendiculata (D. Don) Makino (Orchidaceae) as a potent inhibitor of angiogenesis. It inhibited basic fibroblast growth factor (bFGF)-induced in vitro angiogenesis and in vivo angiogenesis of the chorioallantoic membrane (CAM) of chick embryo without showing any toxicity.
Campbell Sonia - - 2004
Marine sand and seawater samples were collected in March 2002 from Laysan Island in the Hawaiian Islands National Wildlife Refuge, where a small area was contaminated by the carbamate insecticide carbofuran. Carbofuran was still detected at microg g(-1) levels in the Laysan sand after its identification in 1998 and initial ...
Antunes Sara C - - 2004
The toxic effects of lindane on the zooplankton communities may be strongly related to the population fitness, which is highly dependent on food availability. In order to test this hypothesis, acute (immobilisation) and chronic (life-history) responses of Daphnia longispina and Daphnia magna, reared at different food levels (low, normal, and ...
Bradberry Sally M - - 2004
Glyphosate is used extensively as a non-selective herbicide by both professional applicators and consumers and its use is likely to increase further as it is one of the first herbicides against which crops have been genetically modified to increase their tolerance. Commercial glyphosate-based formulations most commonly range from concentrates containing ...
Choudhary Shamim - - 2004
Fenvalerate, a synthetic pyrethroid, was analysed for its toxic effects on Drosophila melanogaster. It has been estimated that LC50 0.0166 micro 1/100 ml food is threshold of lethality. These studies have also revealed that fenvalerate is toxic as it had a pronounced effect on the rate of development and viability.
Kroes R - - 2004
The threshold of toxicological concern (TTC) is a pragmatic risk assessment tool that is based on the principle of establishing a human exposure threshold value for all chemicals, below which there is a very low probability of an appreciable risk to human health. The concept that there are levels of ...
Lasky Tamar - - 2004
The purpose of this study was to estimate mean concentrations of total arsenic in chicken liver tissue and then estimate total and inorganic arsenic ingested by humans through chicken consumption. We used national monitoring data from the Food Safety and Inspection Service National Residue Program to estimate mean arsenic concentrations ...
Vela Nohora P - - 2004
Health risk associated with dietary arsenic intake may be different for infants and adults. Seafood is the main contributor to arsenic intake for adults while terrestrial-based food is the primary source for infants. Processed infant food products such as rice-based cereals, mixed rice/formula cereals, milk-based infant formula, applesauce and puree ...
Gomes Rachel L - - 2004
The bioaccumulation of estrone by Daphnia magna was determined. Direct uptake via the aqueous medium occurred within the first 16 h. A bioconcentration factor of 228 was established over all temporal periods. Ingestion via Chlorella vulgaris gave a partitioning factor of 24, which may approximate to a biomagnification factor assuming ...
Yorulmazlar Emre - - 2003
This study attempts to determine the 96-h LC50 values of CdSO4 x H2O, a metal salt widely used in industry, for grass carp (Ctenopharyngodon idellus Val., 1844). The study was carried out in two stages with 120 grass carp individuals using statistic method of aquatic toxicity. In addition, the behavioral ...
Viñas P - - 2003
The stability of arsenobetaine in baby foods under different experimental conditions is evaluated. Total arsenic was analyzed by electrothermal atomic absorption spectrometry, and the speciation of arsenicals was carried out by coupling liquid chromatography to hydride generation-atomic absorption spectrometry. The highest arsenic levels in the analyzed baby foods corresponded to ...
Blunden Steve - - 2003
Tinplate is light gauge, steel sheet or strip, coated on both sides with commercially pure tin and has been used for well over a hundred years as a robust form of food packaging. Altogether, about 25,000 million food cans are produced and filled in Europe per annum, about 20% of ...
Huang Yung-Kay - - 2003
A study was conducted to measure the arsenic species in farmed mouthbreeder (Oreochromis mossambicus) and culture ponds in water in blackfoot disease (BFD) hyperendemic areas in Taiwan. The relationships between arsenic species of aquaculture ponds and farmed fish were also explored. Biota samples were extracted with methanol/water (1/1, v/v) using ...
Katano Seiji - - 2003
We investigated the water-soluble arsenic compounds present in the soft tissues of both the pearl-free and the pearl-containing pearl oysters. After dividing the soft tissue into five parts, i.e., adductor muscle, foot, mantle, viscera and gill, each part was analyzed by high-performance liquid chromatography-inductively coupled plasma mass spectrometry for the ...
Delgado-Andrade C - - 2003
The total concentration of arsenic in different foods from south-east Spain was determined by hydride generation atomic absorption spectrometry. Mineralization was carried out with an HNO(3)-HClO(4) mixture in a thermostated sand bath. Arsenic determination was performed by the standard addition method. Analyses of NIST and CBR-CEC reference materials demonstrated the ...
Joshi Himanshu - - 2003
Arsenic rarely occurs in free state and is generally found in combination with Sulphur, Oxygen and Iron. In the environment, Arsenic occurs as a result of several inputs that contain this element in organic and inorganic forms. Arsenic is present in Coal, Lead, Zinc, Gold and Copper ores in the ...
Tsui Martin T K - - 2003
Glyphosate-based herbicides (e.g. Roundup) are extensively used in the aquatic environment, but there is a paucity of data on the toxicity of the formulated products and the influences by environmental factors. In this study, the acute toxicity of technical-grade glyphosate acid, isopropylamine (IPA) salt of glyphosate, Roundup and its surfactant ...
Chandra Sekhar K - - 2003
Different areas in the industrial region of Patancheru near Hyderabad, Andhra Pradesh (A.P), India are contaminated with high concentration of arsenic, which is attributed to industrial source like veterinary chemicals, pharmaceuticals, pesticide industries, etc. Fourteen villages of this area of Patancheru were assessed for arsenic contamination by collecting samples of ...
Bellis David J - - 2003
ICP-MS analysis recorded historical change (c. 1846 to 2002) in the arsenic concentration of bark included within the trunks (tree bark pockets) of two Japanese oak trees (Quercus crispula), collected at an elevated location approximately 10 km from the Ashio copper mine and smelter, Japan. The arsenic concentration of the ...
Liao Chung-Min - - 2003
The general objective of our work was to determine the acute toxicity and bioaccumulation of arsenic (As) in tilapia (Oreochromis mossambicus) from the blackfoot disease (BFD) area in Taiwan. The average concentration of As in pond water ranged from 17.8 to 49 microg L(-1). Acute toxicity tests showed that the ...
Milstein Lisa S - - 2003
Several sample preparation techniques were investigated to maximize the efficiency of arsenic species extraction from food composites. The optimized method includes lyophilization of food followed by prewashing with acetone and extraction by sonication with 50/50 methanol/water. Six arsenic species were separated and quantitated using an ammonium carbonate buffer system by ...
He Jianzhong - - 2003
Tetrachloroethene (PCE) and trichloroethene (TCE) are ideal solvents for numerous applications, and their widespread use makes them prominent groundwater pollutants. Even more troubling, natural biotic and abiotic processes acting on these solvents lead to the accumulation of toxic intermediates (such as dichloroethenes) and carcinogenic intermediates (such as vinyl chloride). Vinyl ...
Ratnaike R N - - 2003
Arsenic toxicity is a global health problem affecting many millions of people. Contamination is caused by arsenic from natural geological sources leaching into aquifers, contaminating drinking water and may also occur from mining and other industrial processes. Arsenic is present as a contaminant in many traditional remedies. Arsenic trioxide is ...
Kohlmeyer Ute - - 2003
A recently developed and validated method for simultaneous determination of 17 inorganic and organic arsenic compounds in marine biota has been successfully applied to routine analysis of different food products, including fish, shellfish, edible algae, rice, and other types of grain. During one year, approximately 250 food samples were analyzed, ...
Bianchini Adalto - - 2003
Daphnids (Daphnia magna) were exposed to AgNO3 at 0.303 +/- 0.017 microg silver/L (46.9% as Ag+), in the absence of food, in moderately hard synthetic water under static conditions for up to 48 h. Results from accumulation experiments demonstrated that silver body burden was inversely related to body mass. Daphnids ...
Roychowdhury Tarit - - 2003
An investigation of arsenic, copper, nickel, manganese, zinc and selenium concentration in foodstuffs and drinking water, collected from 34 families and estimation of the average daily dietary intake were carried out in the arsenic-affected areas of the Jalangi and Domkal blocks, Murshidabad district, West Bengal where arsenic-contaminated groundwater (mean: 0.11 ...
Péry A R R - - 2003
DEBtox model is a biologically based model used to analyse aquatic toxicity data (The analysis of aquatic toxicity data, VU University Press, Amsterdam, The Netherlands, 1996, 149pp.). To date, it has not been used to analyse sediment survival tests, mainly because this would require daily counting of survivors, which is ...
Herbrandson Carl - - 2003
It has been demonstrated that simultaneous exposure of Daphnia magna to suspended solids and a carbamate pesticide potentiates the toxic response to the pesticide. The toxicodynamics between these stressors were investigated to determine possible mechanisms of interaction. Three experimental series were conducted with D. magna to determine: the effect of ...
Christoffersen Kirsten - - 2003
The toxicity of linear alkyl benzene sulfonate (LAS) to marine invertebrates is well documented under laboratory conditions using single-species tests. It is less known how LAS affects natural populations of aquatic organisms. We hypothesised that LAS was more toxic to the calanoid copepod Acartia sp. under natural conditions than Acartia ...
Abernathy Charles O - - 2003
Humans can be exposed to arsenic (As) through the intake of air, food and water. Although food is usually the major source of As exposure for people, most adverse effects are seen after As exposure from drinking water. The two main reasons for this situation are that most food arsenicals ...
Patrick Lyn - - 2003
Exposure to toxic metals has become an increasingly recognized source of illness worldwide. Both cadmium and arsenic are ubiquitous in the environment, and exposure through food and water as well as occupational sources can contribute to a well-defined spectrum of disease. The symptom picture of arsenic toxicity is characterized by ...
Garbarino J R - - 2003
Roxarsone, 3-nitro-4-hydroxyphenylarsonic acid, is an organoarsenic compound that is used extensively in the feed of broiler poultry to control coccidial intestinal parasites, improve feed efficiency, and promote rapid growth. Nearly all the roxarsone in the feed is excreted unchanged in the manure. Poultry litter composed of the manure and bedding ...
Hansen H R - - 2003
Information on the effects of long-term organoarsenical consumption by mammals is limited despite the fact that foodstuffs, especially seafood, often contain organoarsenicals at very high concentrations. Here we evaluate the intake, uptake, and excretion (urine and feces) of arsenic by sheep that live on North Ronaldsay in the Orkney Islands ...
Hadi Abdullahel - - 2003
The study evaluates the arsenic mitigation project of BRAC in raising awareness of arsenic poisoning in rural communities in Bangladesh. Data came from selected project villages in south-western Bangladesh. Comparison villages were also selected from the same region. A total of 1240 randomly selected adults were interviewed in May 2000. ...
Barbaste M - - 2003
Because of their high toxicity, arsenic, lead and cadmium need to be quantified in food and beverages. For the first time, in this study the content of arsenic, lead and cadmium was investigated in 152 wine samples from the Canary Islands, Spain, belonging to eight Denominations of Origin (DO) and ...
Bondy Genevieve - - 2003
Due to widespread usage of the pesticide chlordane until the 1980's, this toxic and persistent mixture has accumulated in the food chain. The Arctic acts as a global sink for these and other persistent organic pollutants, which bioaccumulate in the marine and freshwater food chains. As a result, humans consuming ...
Faimali Marco - - 2003
The antifouling activity and toxicity of polymeric 3-alkylpyridinium salts (poly-APS) isolated from the Mediterranean sponge Reniera sarai were studied. The activity of these natural products was compared to that of zinc and copper complexes of pyrithione, two non-persistent booster biocides successfully used in current antifouling coatings. Larvae of Balanus amphitrite ...
Hsueh Yu-Mei - - 2003
The objective of this study was to assess individual variation in inorganic arsenic methylation capability and the association between selenium levels in urine and blood, and inorganic arsenic methylation capability among residents of the Lanyang Basin who drank groundwater and were exposed to high concentrations of inorganic arsenic. According to ...
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