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Results 351 - 400 of 591
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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 ...
Mahata J - - 2003
Arsenic contamination in groundwater has become a worldwide problem. Currently an unprecedented number of people in West Bengal, India and Bangladesh are exposed to the ubiquitous toxicant via drinking water in exposure levels far exceeding the maximum recommended limit laid down by WHO. This arsenic epidemic has devastated nine districts ...
Anderson B S - - 2003
The Salinas River is the largest of the three rivers that drain into the Monterey Bay National Marine Sanctuary in central California. Large areas of this watershed are cultivated year-round in row crops and previous laboratory studies have demonstrated that acute toxicity of agricultural drainwater to Ceriodaphnia dubia is caused ...
Rahman Mohammad Mahmudur - - 2003
To understand the magnitude of the arsenic calamity in West Bengal, a detailed study spanning 7 years was made in North 24-Parganas, one of the nine arsenic affected districts. Area and population of North 24-Parganas district are 4093.82 sq. km and 7.3 million, respectively. Fourty eight thousand and thirty water ...
Huq M A - - 2003
In a study observing the effect of spirulina in the treatment of chronic arsenic poisoning quantitative estimation of arsenic in the urine of the patients was necessary. It was decided to try a modification of the arsine generator in the process. An alternative apparatus was designed following the structure of ...
Cancilla Devon A - - 2003
This paper presents the results of a number of field and laboratory studies to evaluate the environmental impact of aircraft deicing and anti-icing fluids (ADAFs) on aquatic systems. Both 5-methyl-1H-benzotriazole (5-MeBt) and 4-methyl-1H-benzotriazole (4-MeBt), known additives to ADAFs, were found in whole-tissue extracts from minnows placed downstream of an effluent ...
Schiff Kenneth - - 2003
Stormwater discharges from Chollas Creek, a tributary of San Diego Bay, have been shown to be toxic to aquatic life. The primary objective of this study was to provide the linkage between in-channel measurements and potential impairments in the receiving waters of San Diego Bay. This study addressed this objective ...
Belgis Chial - - 2003
As important members of zooplankton communities worldwide, rotifers are used extensively in ecotoxicological research. Chronic rotifer tests are, however, dependent on live algal food which adds to the complexity, the variability and the costs of these bioassays. To bypass the former problem, experiments have been undertaken with the freshwater rotifer ...
Hussam A - - 2003
The presence of toxic level of inorganic arsenic in groundwater used for drinking in Bangladesh and neighboring India is unfolding as one of the worst natural disaster in the region. The purpose of this work is to ascertain the chemical fate of arsenic and other metals in groundwater of Bangladesh. ...
Pavittranon Sumol - - 2003
Ronpibul village dwellers in the southern part of Thailand have been exposed to arsenic in the water and the environment over three generations. Over the past decades, clean water supplies, utilization and consumption have been introduced to the area. The villagers still use and select rainwater to other forms of ...
Kadono Takafumi - - 2002
BACKGROUND: Arsenic contamination in groundwater affects 35 million people in Bangladesh, but the prevalence of arsenic contamination in local communities remains to be clarified. As skin manifestations are sensitive markers of arsenicosis, we examined the skin of adults and adolescents in two villages to elucidate the severity of arsenicosis. METHODS: ...
Rice Karen C - - 2002
Mass balances of total arsenic and copper for a suburban lake in densely populated northern Virginia were calculated using date collected during 1998. Mass-balance terms were precipitation; stream inflow, including road runoff; stream outflow; and contributions from leaching of pressure-treated lumber. More mass of arsenic and copper was input to ...
Roychowdhury T - - 2002
An investigation of total arsenic in food composites, collected from the villagers, was carried out in arsenic-affected areas of the Murshidabad district, West Bengal where the agricultural system is mostly groundwater dependent. The shallow, large-diameter tubewells installed for agricultural irrigation contain an appreciable amount of arsenic (mean 0.085 mg/l, n=6). ...
Rosen Barry P - - 2002
All living organisms have systems for arsenic detoxification. The common themes are (a) uptake of As(V) in the form of arsenate by phosphate transporters, (b) uptake of As(III) in the form of arsenite by aquaglyceroporins, (c) reduction of As(V) to As(III) by arsenate reductases, and (d) extrusion or sequestration of ...
Del Razo L M - - 2002
The aim of this paper is to estimate the levels of arsenic (As) ingestion through cooked foods consumed in an arsenic endemic area and the assessment of their dietary intake of As. The study was conducted in two villages: a population chronically exposed to a high concentration of As via ...
Charles G D - - 2002
The application of organic, conventional and biotechnology techniques can alter the intrinsic levels of natural toxicants in crop foods and methods are needed to screen for unexpected changes in toxicant levels. We evaluated crude, aqueous preparations of 37 foods purchased from a local market in a battery of four in ...
Bielmyer Gretchen K - - 2002
In aqueous media, ionic silver concentrations are low and transport occurs in the colloidal phase. In the aquatic environment, silver forms 1:1 complexes with thiol-containing compounds such as cysteine and glutathione. In order to quantitatively characterize the risk associated with silver in aquatic ecosystems, the bioavailabilities and toxicities of silver ...
De Silva P M C S - - 2002
Chlorpyrifos (O,O-diethyl-O (3,5,6-trichlor-2-pyridyl) phosphorothioate) is a broad-spectrum organophosphate compound. A number of previous work of different countries, institutes, and individuals have confirmed that chlorpyrifos is very highly toxic to freshwater fish and to aquatic invertebrates. The acute toxicity and subacute toxic effects on different concentrations of chlorpyrifos in guppy were ...
Furst A - - 2002
Universally, the general population is exposed to a variety of "toxic" substances. Some of these are from manufactured goods and some from air and water pollution. Toxins are also normally found in many foods; however, unless the exposure is overwhelming, we are many times (even unknowingly) protected by the foods ...
Mandal Badal Kumar - - 2002
This review deals with environmental origin, occurrence, episodes, and impact on human health of arsenic. Arsenic, a metalloid occurs naturally, being the 20th most abundant element in the earth's crust, and is a component of more than 245 minerals. These are mostly ores containing sulfide, along with copper, nickel, lead, ...
Marchant Gary E - - 2002
One of the first practical applications of toxicogenomics will probably be in the context of toxic tort personal injury litigation. Gene expression changes that'fingerprint' exposure to particular classes of toxic substances can potentially be used to demonstrate exposure, prove causation and support novel damage claims in lawsuits brought by citizens ...
Hsueh Yu Mei - - 2002
In order to understand whether ingestion of seafood affects the urinary arsenic metabolites. About 42 women and 36 men were recruited from the students, parents and teachers in Taipei Medical University and National Taiwan University. The study subjects were interviewed about dietary habits, cigarette smoking habits, drug and vitamin intake, ...
Sternowsky Hans-J - - 2002
Increased concentrations of arsenic were found in soil and ground water from a military training area in Munster, Lower Saxony, Germany, where chemical weapons were dumped after World War II. In order to assess the possible impact of this contamination for nursing new-borns and infants, samples from breast milk of ...
Lima Nadja Maria Fernandes - - 2002
The toxicity of soluble derivatives (potassium salt) of lapachol and isolapachol in different stages of the life cycle of Schistosoma mansoni is evaluated. The potassium salts of isolapachol and lapachol showed significant molluscicidal activity against the adult snail (LC90<7 ppm) and snail egg masses (LC90<3 ppm). Cercaricidal assays revealed strong ...
Redman Aaron D - - 2002
Arsenic mobility in natural environments is controlled primarily by sorption onto metal oxide surfaces, and the extent of this sorption may be influenced strongly by the presence of other dissolved substances that interact with surfaces or with arsenic itself. Natural organic matter (NOM), a prevalent constituent of natural waters, is ...
Pesch Beate - - 2002
To investigate the risk of arsenic exposure from a coal-burning power plant in Slovakia on nonmelanoma skin cancer (NMSC) development, a 1996-1999 population-based case-control study was conducted with 264 cases and 286 controls. Exposure assessment was based on residential history and annual emissions (Asres1, Asres2) and on nutritional habits and ...
Gorbi Gessica - - 2002
The long-term effects of Cr(VI) on life history traits of Daphnia magna Straus were studied in relation to different feeding conditions or to the presence of Scenedesmus acutus exudates, which had proved to reduce chromium toxicity to the alga. In high feeding conditions the concentration of 14 microg Cr(VI)/L had ...
Peshin Sharda Shah - - 2002
The potential toxicants in food are derived from natural or industrial sources. Compounds like lectins and glycoalkaloids that are toxic to man are naturally present in some vegetables like potatoes or legumes. A wide variety of marine toxins mostly produced by dinoflagellates occurring secondarily in molluscs and mussels are usually ...
Mangas-Ramírez Ernesto - - 2002
Ammonia is a natural variable in ponds and lakes. Although an important source of nitrogen for microalgae, at high concentrations ammonia can affect the density and diversity of cladocerans. Using the cladocerans Ceriodaphnia dubia, and Moina macrocopa, the effect of nominal concentrations of ammonium chloride under acute and chronic exposures ...
Jin-Clark Ying - - 2002
Toxicities of two triazine herbicides (atrazine and cyanazine) and an organophosphate insecticide (chlorpyrifos) were evaluated individually and with each herbicide in binary combination with chlorpyrifos using fourth-instar larvae of the aquatic midge, Chironomus tentans. Chlorpyrifos at 0.25 microg/L resulted in an effect in less than 10% of midges in 48-h ...
Almela C - - 2002
The total arsenic, inorganic arsenic, lead, cadmium, and mercury contents of 18 algae food products currently on sale in Spain were determined. The suitability of the analytical methodologies for this type of matrix was confirmed by evaluating their analytical characteristics. The concentration ranges found for each contaminant, expressed in milligrams ...
Geiszinger Anita E - - 2002
Arsenic compounds in the marine polychaete Arenicola marina collected from Odense Fjord, Denmark were determined by HPLC-ICPMS. In contrast to most other marine animals, A. marina contained most of its water soluble arsenic as inorganic forms, arsenite (58%) and arsenate (16%), and arsenobetaine was present as a minor constituent (6%) ...
Rose R M - - 2002
The effect of three chemicals with different mechanisms of action (3,4-dichloroaniline, fenoxycarb, and chlorpyrifos) on the life history response of the cladoceran Ceriodaphnia cf. dubia was examined under both limited (3 x 10(4) cells/mL) and abundant (15 x 10(4) cells/mL) food conditions. Toxicity tests were conducted at both food concentrations ...
Liu Jie - - 2002
Arsenic is an environmental hazard and the reduction of drinking water arsenic levels is under consideration. People are exposed to arsenic not only through drinking water but also through arsenic-contaminated air and food. Here we report the health effects of arsenic exposure from burning high arsenic-containing coal in Guizhou, China. ...
Dybing E - - 2002
Hazard characterisation of low molecular weight chemicals in food and diet generally use a no-observed-adverse-effect level (NOAEL) or a benchmark dose as the starting point. For hazards that are considered not to have thresholds for their mode of action, low-dose extrapolation and other modelling approaches may be applied. The default ...
Solo-Gabriele Helena M - - 2002
The combustion of recovered wood from construction and demolition waste as biomass fuel is a common practice. When chromated copper arsenate (CCA)-treated wood is present as part of the wood fuel mix, concentrations of arsenic, chromium, and copper become elevated in the ash. The objectives of this study were to ...
Kim Myoung-Jin - - 2002
Groundwater samples, taken from 73 wells in 10 counties of southeast Michigan in 1997 had arsenic concentrations in the range of 0.5 to 278 microg/L the average being 29 microg/l. About 12% of these wells had arsenic concentrations that exceeded the current USEPA's maximum contaminant level of 50 microg/l. Most ...
Van Geen Alexander - - 2002
OBJECTIVE: To survey tube wells and households in Araihazar upazila, Bangladesh, to set the stage for a long-term epidemiological study of the consequences of chronic arsenic exposure. METHODS: Water samples and household data were collected over a period of 4 months in 2000 from 4997 contiguous tube wells serving a ...
Preston Benjamin L - - 2002
The analysis of spatial relationships among the distribution of environmental stressors and observed or predicted adverse effects may be a useful method of prioritizing hazards in regional ecological risk assessment (ERA). Geographic information systems were used to compare the spatial distribution of toxicant concentrations in sediments of Chesapeake Bay with ...
Shang Neng-Chou - - 2002
This study investigates the variation of toxicity during ozonation of 2-chlorophenol (2-CP), 3-chlorophenol (3-CP) and 4-chlorophenol (4-CP) in neutral condition. Acute toxicity of pure chlorophenols (CPs) and their ozonated intermediates was evaluated by Microtox assay. The results revealed that the intermediates of oxidized CPs induced new toxicity during the early ...
Suhendrayatna - - 2002
Accumulation, transformation and toxicity of arsenic compounds to Japanese Medaka, Oryzias latipes were investigated. For sodium arsenite [As(II)] and disodium arsenate [As(V)], the mean value for 7-day lethal concentration LC50 for O. latipes were 14.6 and 30.3 mg As/l, respectively. Direct accumulation of arsenic in O. latipes increased as a ...
Wang Xiaodong - - 2002
The comparative toxicities of selected phenols to higher plants Cucumis sativus were measured and the negative logarithm molar concentration of the root elongation median inhibition (IRC50) were derived. Quantitative structure-activity relationships (QSARs) were developed to explore the toxicity influencing factors and for predictive purpose. The toxicity data, fell into two ...
Yokota H - - 2002
In March 1997, we analyzed the water of all tubewells used for drinking in Samta village in the Jessore district, Bangladesh. It has been confirmed from the survey that the arsenic contamination in Samta was one of the worst in the Ganges basin including West Bengal, India. 90% of the ...
Wiseman Alan - - 2002
The definition of clean bioprocessing of foods should relate to the discharge of clean effluents that do not disturb functional ecosystems in the environment. Clean effluents should not pollute aquatic or terrestrial environments by increasing the levels or determined bioavailibility of reactive oxygen species (ROS), traces of heavy metals (e.g. ...
Muñoz I - - 2001
An experiment was carried out using indoor experimental channels to assess the long-term effect (18 days) of herbivores (Physella acuta, Gastropoda) on periphyton communities exposed to low levels of atrazine (14 microg l(-1)). We hypothesized that herbivorism modifies the response of periphyton to atrazine. Carbon incorporation, chlorophyll-a content, biovolume and ...
Storelli M M - - 2001
Total, organic, and inorganic arsenic were measured in the flesh of different crustacean species: Parapenaeus longirostris, Aristeus antennatus, Plesionika martia, and Nephrops norvegicus, species extensively commercialized and widely consumed as food. Among the different species of crustaceans, the highest mean value of total arsenic was detected in N. norvegicus (45.00 ...
Vasconcelos V - - 2001
The occurrence of cyanobacteria in many water bodies where crayfish such as Procambarus clarkii are abundant leads to the possibility of toxin accumulation and food chain transfer. This paper describes the accumulation and depuration of microcystins from a microcystin and a non-microcystin producing strain of Microcystis aeruginosa, on the survivorship, ...
Brust K - - 2001
The effects of the herbicide terbutryn on a simple lotic food web were investigated during a 72-d exposure period in five artificial indoor streams in a greenhouse. The model compound terbutryn, an s-triazine and an inhibitor of photosynthesis, was applied once in each stream at nominal concentrations of 0.6, 6, ...
Cerstiaens A - - 2001
Little information is available on the systemic effects of Bacillus thuringiensis toxins in the hemocoel of insects. In order to test whether B. thuringiensis-activated toxins elicit a toxic response in the hemocoel, we measured the effect of intrahemocoelic injections of several Cry1 toxins on the food intake, growth, and survival ...
Johnson A A - - 2001
To examine the role of the mitochondrial polymerase (Pol gamma) in clinically observed toxicity of nucleoside analogs used to treat AIDS, we examined the kinetics of incorporation catalyzed by Pol gamma for each Food and Drug Administration-approved analog plus 1-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)-5-iodouracil (FIAU), beta-L-(-)-2',3'-dideoxy-3'-thiacytidine (-)3TC, and (R)-9-(2-phosphonylmethoxypropyl)adenine (PMPA). We used recombinant exonuclease-deficient ...
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