Search Results
Results 501 - 550 of 823
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Crews H - - 2001
In this review many examples are given of the complexities involved in using some biomarkers in relation to assessing the effects of dietary exposure, when there is frequently a need to determine changes following long-term low level exposure to dietary components. These range from understanding why the biomarker might be ...
Bernard C E - - 2001
Intentional and unavoidable human exposure is a consequence of using pesticides to nurture and protect residential turf. Limited exposure studies have been conducted for assessing potential human exposure of turf residues. Exposure was measured in persons who performed a 20-minute structured activity (Jazzercise) on chlorpyrifos (CP)-treated Kentucky bluegrass (12 +/- ...
Rowe C L - - 2001
Recent studies of several vertebrates and an invertebrate have shown elevated standard metabolic rate (SMR) following chronic exposure to a mixture of trace elements in a contaminated habitat. In this study, we examined whether another invertebrate, a crayfish (Procambarus acutus), also experienced elevated SMR in response to the same contaminants. ...
Guo X - - 2001
To examine the contribution of various foods to exposure to 2,3,7,8-tetrachloro-p-dibenzodioxin (TCDD) in a background-exposed U.S. population, serum TCDD levels were examined in relation to diet as assessed by a standard diet assessment instrument among men with no known unusual exposure to TCDD. Our subjects were male veterans aged 42-76 ...
Carrington C D - - 2001
Public health risk assessments often involve dietary exposures over long periods of time. However, most information about dietary consumption habits comes from short-term surveys that are conducted for periods of three days or less. When employed for characterizing long-term exposures, short-term surveys are likely to underestimate the number of persons ...
Lorber M - - 2001
In the early 1980s, exposures and subsequent health impact assessments from contaminants emitted into the air from stationary sources focused on the inhalation pathway. This 'direct' pathway of exposure was thought to be the most critical pathway, as it is for many contaminants. However, by the latter 1980s, the focus ...
Isenberg A - - 2001
Recreational sun exposure of the general population has increased. There is less clothing on the beaches, increased accessibility to tropical beaches, and increased use of artificial suntanning equipment. The vulva, traditionally, has been protected from sun exposure. In this age of nude sunbathing, particularly within the confines of a tanning ...
Harris S - - 2001
Lead exposure is still a national concern, and it is possible that Native Americans who live on reservations and pursue traditional lifestyles may be at higher risk through both their unique exposure profiles and their potentially greater sensitivity. A major component of the exposure assessment is the diet. For tribal ...
Jensen E - - 2001
As one of the main components of risk assessment, exposure assessment plays a key role in evaluating risk. Many different scenarios can be developed to estimate the risk from exposure to chemicals such as persistent organic pollutants (POPs). The US Food and Drug Administration (FDA)'s Center for Food Safety and ...
Nouwen J - - 2001
Two municipal waste incinerators in the vicinity of a residential area close to the city of Antwerp caused concern to local habitants. Risk assessment was performed combining chemical, toxicological measurements and model calculations. As the first step in risk assessment an inventory was made of historic emissions from both incinerators ...
Beauvais S L - - 2001
Pesticides and heavy metals are common environmental contaminants that can cause neurotoxicity to aquatic organisms, impairing reproduction and survival. Neurotoxic effects of cadmium and carbaryl exposures were estimated in larval rainbow trout (RBT; Oncorhynchus mykiss) using changes in physiological endpoints and correlations with behavioral responses. Following exposures, RBT were videotaped ...
Rayburn A L - - 2001
The agronomically important herbicide atrazine has been reported to cause damage to animal chromosomes at levels of atrazine found contaminating drinking water supplies. While documenting potential chromosome damage is important it is equally important to compare the damage with the potential consequences of compounds readily found in our food and ...
Powell S - - 2001
Residential exposure assessment is in an early stage of development within many of the regulatory agencies responsible for pesticides. Some of the impetus for residential assessment comes from the Food Quality Protection Act (FQPA), a federal law adopted in 1996 in the USA. The FQPA mandates that the aggregate and ...
Pellizzari E D - - 2001
A National Human Exposure Assessment Survey (NHEXAS) was performed in U.S. Environmental Protection Agency (U.S. EPA) Region V, providing population-based exposure distribution data for metals and volatile organic chemicals (VOCs) in personal, indoor, and outdoor air, drinking water, beverages, food, dust, soil, blood, and urine. One of the principal objectives ...
Fortoul T I - - 2001
During the conduct of autopsies performed on residents of Mexico City during the 1960s (20 males, 19 females) and 1990s (30 males and 18 females), concentrations of manganese in lung were studied with atomic absorption spectrometry. Concentrations of manganese were not significantly greater in the samples obtained in the 1990s ...
Wagner W M - - 2001
A standard radiographic procedure was developed for the thoraco-abdominal cavity of female nonbreeding ostriches. Positioning, collimation, centering and a technique chart were defined to give reproducible and consistently good quality radiographs. Radiographs were obtained from one adult ostrich cadaver, two adult female ostriches as well as two growing ostriches at ...
Anil S - - 2001
Adherence of Candida albicans has been implicated as the first step in the pathogenesis of oral candidosis, and its relative cell surface hydrophobicity (CSH) a contributory physical force. Chlorhexidine gluconate is by far the commonest antiseptic mouthwash prescribed in dentistry. The intra-oral concentrations of the retained chlorhexidine mouthwash fluctuate considerably ...
Santos-Burgoa C - - 2001
To support a risk assessment of manganese exposure in two communities living within a manganese mining district a cross-sectional study was performed on a sample of the adult population of long-term residents. One community was exposed to a point source from an ore primary refining plant. Manganese is an essential ...
Onabolu A - - 2001
OBJECTIVE: To investigate if high cassava production levels indicate high consumption and high dietary cyanide exposure in three villages situated within the area of Nigeria with higher cassava production than predicted by a geographic model for cassava production in Africa. DESIGN: Exploratory assessment of: cassava production and processing by qualitative ...
Roels H A - - 2001
The present study aimed to assess whether urinary germanium concentration can be used as a biomarker of inhalation exposure to airborne dust from metallic germanium (Ge) or GeO2 in the occupational setting. A novel hydride generation-based method coupled with fow-injection graphite furnace atomic absorption spectrometry (HG/FI-GFAAS) was developed for the ...
Kezic S - - 2001
The dermal absorption of liquid 1,1,1-trichloroethane (111TRI), trichloroethene (TRI), tetrachloroethene (TETRA), toluene (TOL), and m-xylene (XYL) was studied in volunteers. The solvents were applied for 3 min on the volar forearm over an area of 27 cm2. An inhalation exposure with a known input rate served as a reference exposure. ...
McDonald T A - - 2001
High background levels of phenol and hydroquinone are present in the blood and urine of virtually all individuals, but vary widely. Phenol and hydroquinone have been strongly implicated in producing leukemia associated with benzene exposure, because they reproduce the hematotoxicity of benzene, cause DNA and chromosomal damage found in leukemia, ...
Muranko H J - - 2001
This article describes an industrywide exposure assessment study of "total" and respirable carbon black dust exposures among U.S. carbon black manufacturing workers conducted between 1993 and 1995. In addition to updating a 1979-1980 industrywide "total" dust study conducted among all major U.S. carbon black producers, this research was the first ...
Hopkins W A - - 2001
Compared with birds, mammals, fish, and even amphibians, very little is known about the effects of contaminants on reptiles. Recent evidence that many reptile populations may be declining has stimulated demand for toxicological studies of reptiles as well as development of nondestructive sampling techniques useful for assessing and monitoring contaminant ...
Mage D T - - 2001
Modern epidemiology has shown that fluctuations of mortality data are statistically significantly correlated with fluctuations of ambient particulate matter (PM) concentration data. This relation cannot be confounded by exposure to PM of indoor origin because the concentrations of ambient PM are not correlated with concentrations of PM of indoor origin. ...
Bud P - - 2000
There is a considerable body of evidence to support the contention that the atmospheric Pb burden is now considerably greater than it was in the remote past. However, as there are a diversity of potential environmental pathways leading to Pb ingestion, it is not clear how atmospheric Pb levels relate ...
Carrer P - - 2000
Personal exposure to total volatile organic compounds (TVOCs), benzene and toluene of 100 Milan office workers was assessed through personal air monitoring at home, in the office, and during commuting. Biological monitoring was performed by measuring blood benzene and toluene concentrations together with urinary trans-trans-muconic acid (t,t-MA) and cotinine at ...
Melnyk L J - - 2000
Children are the most susceptible population to lead exposure because of three interacting factors; they have more opportunity for contact with lead sources due to their activities, lead absorption occurs more readily in a child compared to an adult, and the child's development is more vulnerable to lead than adults. ...
Snyman R G - - 2000
This study investigated the use of lysosomal responses of hemocytes of the common garden snail, Helix aspersa, as biomarker of stress due to exposure to the fungicide copper oxychloride. The neutral red retention (NRR) time assay was employed for this purpose. Two groups of snails were exposed to 80 microg ...
Dougherty C P - - 2000
Food consumption is an important route of human exposure to pesticides and industrial pollutants. Average dietary exposures to 37 pollutants were calculated for the whole United States population and for children under age 12 years by combining contaminant data with food consumption data and summing across food types. Pollutant exposures ...
Aizenberg V - - 2000
Button Aerosol Samplers were used to monitor the personal exposure of workers performing abrasive blasting operations at four U.S. Air Force facilities. Inhalable aerosols containing 25 metals, including cadmium, lead, and chromium, were investigated. The Button Aerosol Sampler was chosen because of its ability to successfully withstand mechanical stress, prevent ...
Bolstad-Johnson D M - - 2000
Previous studies have characterized firefighter exposures during fire suppression. However, minimal information is available regarding firefighter exposures during overhaul, when firefighters look for hidden fire inside attics, ceilings, and walls, often without respiratory protection. A comprehensive air monitoring study was conducted to characterize City of Phoenix firefighter exposures during the ...
Denovan L A - - 2000
A field study was conducted in which saliva samples were collected from a cohort of herbicide applicators during the pre-emergent spray season in Ohio in 1996. Atrazine concentrations were detected in human saliva samples using an enzyme-linked immunosorbent assay (ELISA) method. Trend due to atrazine exposure and subsequent elimination in ...
Grimsrud T K - - 2000
OBJECTIVES: The aim of the study was, on the basis of new information on nickel species and exposure levels, to generate a specific exposure matrix for epidemiologic analyses in a cohort of Norwegian nickel-refinery workers with a known excess of respiratory cancer. METHODS: A department-time-exposure matrix was constructed with average ...
Kirby C - - 2000
Factors concerning NO2 uptake by the absorbent triethanolamine (TEA) in NO2 diffusion tubes are examined. Although the nominal freezing point of TEA is 17.9-21.2 degrees C, we show that, for a range of aqueous TEA solutions (0-20%, H2O), no freezing occurs even at -10 degrees C. Therefore NO2 collection efficiency ...
Budzynski C A - - 2000
The ability of animals to learn to use the sun for orientation has been explored in numerous species. In birds, there is conflicting evidence about the experience needed for sun compass orientation to develop. The prevailing hypothesis is that birds need entire daytime exposure to the arc of the sun ...
Paustenbach D J - - 2000
Each of us encounters hundreds of toxic agents everyday, without exposure and subsequent absorption (uptake) however, there is no risk of injury. Thus, exposure assessment is one of the three legs of the stool (along with toxicity assessment and dose-response assessment) upon which the practice of risk assessment rests. The ...
Weaver V M - - 2000
The benzene metabolite, trans,trans-muconic acid (MA), has been shown to be a sensitive and specific biomarker for ambient benzene exposure levels as low as approximately 0.5 ppm. However, at lower exposure levels, the use of MA as a benzene biomarker is complicated by the fact that it is also a ...
Howard-Reed C - - 2000
In population exposure studies, personal exposure to PM is typically measured as a 12- to 24-hr integrated mass concentration. To better understand short-term variation in personal PM exposure, continuous (1-min averaging time) nephelometers were worn by 15 participants as part of two U.S. Environmental Protection Agency (EPA) longitudinal PM exposure ...
Stefaniak A B - - 2000
Personal and area samples from three copy centres were collected in thermal desorption tubes and analyzed using gas chromatography-mass spectrometry. Real-time personal total volatile organic compounds (TVOC) were measured using a data-logging photoionization detector. Fifty-four different VOCs were detected in the area samples. The maximum concentration measured was 1132.0 ppb ...
Carlton G N - - 2000
Jet fuel and benzene vapor exposures were measured during aircraft fuel tank entry and repair at twelve U.S. Air Force bases. Breathing zone samples were collected on the fuel workers who performed the repair. In addition, instantaneous samples were taken at various points during the procedures with SUMMA canisters and ...
Nilsson R - - 2000
Recently, considerable attention has been focused on certain environmental contaminants--"endocrine disruptors"--of industrial origin that may mimic the action of sex hormones. Natural compounds and their effects on other types of hormonal activity (eg, on adrenal or thyroid function) have for some reason not provoked similar attention. As exemplified by tributyltin ...
Johanson G - - 2000
Ethylene glycol monomethyl ether (EGME) and its acetate ester (EGMEA) are highly flammable, colorless, moderately volatile liquids with very good solubility properties. They are used in paints, lacquers, stains, inks and surface coatings, silk-screen printing, photographic and photo lithographic processes, for example, in the semiconductor industry, textile and leather finishing, ...
Tang W - - 2000
In the present studies, human exposure to styrene and to ethylbenzene (EB) is assessed on the basis of literature data. Total styrene and total EB exposure result from inhalation and from food intake. Styrene and EB inhaled represent the greatest proportion of the total intake. Styrene and EB content in ...
Wester R C - - 2000
Skin is one of several exposure routes whereby benzene, a widely distributed environmental contaminant that causes leukemia, enters the body, so accurate predictions of its percutaneous absorption are important for risk assessment. Determining benzene's skin-exposure dose and subsequent absorption is difficult because it has a low boiling point and exists ...
Cajaraville M P - - 2000
Within the frame of the 2nd Iberian Congress of Environmental Contamination and Toxicology (University of the Basque Country, Leioa, June 1998) a workshop was held about the use of biomarkers in marine pollution monitoring. Among others, the following biomarkers received special attention: metallothionein induction, acetylcholinesterase inhibition, cytochrome P450 system induction, ...
Seifert B - - 2000
The German Environmental Survey (GerES) is a large-scale population study which has repeatedly been carried out in Germany. GerES I was conducted in 1985/1986 followed by GerES IIa in 1990/1991 (West Germany) and GerES IIb in 1991/1992 (East Germany). GerES III is currently run in both parts of Germany. The ...
Pointon A M - - 2000
A systematic quantification of foodborne hazards in abnormal and normal tissues of pig carcases was undertaken to provide a risk-based assessment of the effectiveness of traditional organoleptic meat inspection. A total of 36,059 pigs, representing all major pig-producing areas and systems in Australia, were inspected on a seasonal basis at ...
Schwartz M S - - 1999
OBJECT: Use of orbital rim and orbitozygomatic osteotomy has been extensively reported to increase exposure in neurosurgical procedures. However, there have been few attempts to quantify the extent of additional exposure gained by these maneuvers. Using a novel laboratory technique, the authors have attempted to measure the increase in the ...
Frampton M W - - 1999
We hypothesized that exposure of healthy humans to ozone at concentrations found in ambient air causes both ozonation and peroxidation of lipids in lung epithelial lining fluid. Smokers (12) and nonsmokers (15) were exposed once to air and twice to 0.22 ppm ozone for four hours with exercise in an ...
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