World Library  


 
  • Cover Image

Model Ecosystem Evaluation of the Environmental Impacts of the Yet...

By: Joel R. Coats

Government Reference Publication

Excerpt: Animal wastes are an important contribution to environmental pollution in the United States. The agricultural industry raises annually about 107 million cattle, 53 million hogs, 26 million sheep, 375 million chickens, 104 million turkeys, and 11 million ducks. These animals produce annually about 1.14 x lo9 tons of solid wastes and 4.35 x lo8 tons of liquid wastes (1). Such animal wastes which aggregate about 10 times the U.S. total of human excretory wastes hav...

Read More
  • Cover Image

A Time Series Analysis of Air Pollution and Preterm Birth in Penns...

By: Sharon K. Sagiv

Government Reference Publication

Excerpt: Preterm delivery can lead to serious infant health outcomes, including death and lifelong disability. Small increases in preterm delivery risk in relation to spatial gradients of air pollution have been reported, but previous studies may have controlled inadequately for individual factors. Using a time-series analysis, which eliminates potential confounding by individual risk factors that do not change over short periods of time, we investigated the effect of am...

Read More
  • Cover Image

Rat Liver Subcellular Fractions Catalyze Aerobic Binding of I-Nitr...

By: Joellen Lewtas

Government Reference Publication

Excerpt: 1-Nitropyrene (NP), found in photocopier toners (1,2) and in particulate matter from diesel vehicle emissions (3) and ambient air (41, is a mutagen in bacterial and mammalian assay systems (5-7). NP has also been reported to cause mammary gland tumors in rats (8). Covalently bound adducts formed by interaction of NP with DNA have been detected (9) and characterized in Salmonella typhimurium (10) and in cell-free incubations catalyzed under anaerobic conditions b...

Read More
  • Cover Image

Lesions of Testis and Epididymis Associated with Prenatal Diethyls...

By: Retha R. Newbold

Government Reference Publication

Excerpt: This is a brief review of some developmental changes in the male mouse reproductive tract associated with in utero exposure to a synthetic estrog- en, diethylstilbestrol (DE%). The knowledge that estrogenic compounds affect the earlv differentiation and develoment of the male repro& ctive tract has been evidGt for about 50 years; however, the full range of morphological changes has begun to emerge only recently. Interest in the subject has been promoted by the f...

Read More
  • Cover Image

Pathologic Effects of 2,3,7,8,-Tetrachlorodibenzo-P-Dioxin in Labo...

By: B. N. Gupta

Government Reference Publication

Introduction: The technical chlorophenols and products produced from them, such as the herbicide 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) have been found to contain chlorodibenzo-pdioxins such as 2,3,7,8-tetrachlorodibenzo-pdioxin (TC-DD). TCDD and other chlorodibenzoq- dioxins are among the most toxic compounds known, and have been implicated in outbreaks of chloracne among chemical workers (1) . Hepatic and cardiac lesions and thymic involution were found in rats tr...

Read More
  • Cover Image

Chemical and Biological Investigations of a Transformer Accident a...

By: Patrick W. Okeefe

Government Reference Publication

Excerpt: Since 1977, government regulations in the U.S. have prohibited the manufacture of transformers or capacitors containing polychlorinated biphenyls (PCBs) as dielectric fluids. However, it has been estimated that over 150,000 tons of PCBs are present in capacitors and transformers still in current use. In 1978, laboratory experiments demonstrated that pyrolysis of PCBs at high temperatures (200-600?C) could result in the for-.

Read More
  • Cover Image

National Maps of the Effects of Particulate Matter on Mortality : ...

By: Scott L. Zeger

Government Reference Publication

Excerpt: In this paper, we present national maps of relative rates of mortality associated with short-term exposure to particulate matter < 10 micrometer in aerodynamic diameter (PM10). We report results for 88 of the largest metropolitan areas in the United States from 1987 to 1994 for all-cause mortality, combined cardiovascular and respiratory deaths, and other causes of mortality. Maximum likelihood estimates of the relative rate of mortality associated with PM10 and...

Read More
  • Cover Image

Asbestos Penetration of the Gastrointestinal

By: William H. Hallenbeck

Government Reference Publication

Excerpt: My comments are restricted to studies involving gastrointestinal exposure of humans and animals to asbestos via the diet or intubation. There have been three studies designed to determine whether human ingestion of asbestos in drinking water could result in the detection of asbestos in urine or postmortem tissues (13). One study concluded that ingested asbestos could not be found in human urine (1). However, other studies found evidence that ingested asbestos co...

Read More
  • Cover Image

Where the Boys Arent : Dioxin and the Sex Ratio

By: Piet Hein Jongbloet

Government Reference Publication

Excerpt: Mocarelli and colleagues (1,2) compared about 750 people in a cohort from the most contaminated area to 40,000 people from two zones that were less contaminated by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD or dioxin) after the explosion at a herbicide plant in Seveso, Italy. The authors found a lower proportion of male offspring from exposed fathers (77:100) and a tendency to more male offspring (120:100) from exposed mothers. Clapp and Ozonoff (3) describe thes...

Read More
  • Cover Image

Strategic Partnering to Evaluate Cancer Signatures

By: United Nations

Government Reference Publication

Excerpt: Retrospective studies have shown that molecular signatures have identified subgroups of patients whose tumors are histopathologically the same but who have different clinical outcomes. The challenge is to translate the information in these molecular signatures into tools that can be used in clinical decision making. To meet this challenge, signatures must be confirmed in independent studies. Critical elements of signatures that correlate most strongly with the c...

Read More
  • Cover Image

Differential Gene Expression during Multistage Carcinogenesis

By: G. Tim Bowden

Government Reference Publication

Introduction: During the process of either chemical or radiation carcinogenesis, the progression of target cells through a premalignant to malignant state is accompanied by a variety of morphological, cytological, and biochemical alterations. Presumably, these phenotypic changes result from either qualitative alterations in encoded gene products or changes in the levels of expression of cellular genes. One class of cellular genes that is known to be altered during carcin...

Read More
  • Cover Image

Toxic Oil Timeline Diagnosing Effects Decades Later

By: Ernie Hood

Government Reference Publication

Excerpt: Two decades after contaminated cooking oil caused widespread sickness in Spain, patients with so-called toxic oil syndrome (TOS) continue to report neurologic symptoms. Accurately assessing these symptoms?which include headache, insomnia, and muscle weakness? has been challenging, because the symptoms are numerous and tend to be vague. Standard clinical examinations have detected few or no problems, and patients have sometimes been accused of exaggerating or mal...

Read More
  • Cover Image

Tradescantia Micronucleus Bioassay and Pollen Tube Chromatid Aberr...

By: Te Hsiu Ma

Government Reference Publication

Introduction: Tradescantia, commonly called spiderwort, is a bust and multi-branched species became a popular herbaceous plant which has almost world-wide atl- cytogenetic experimental material since the late aptation and can grow around the year in the field 1930s (1-5). Extensive studies of the direct and of subtropical regions of the world or in green- indirect effects of radiation on mitotic chromosomes houses everywhere. Its relative small plant size of microspores ...

Read More
  • Cover Image

The Need for Better Methods of Extrapolation

By: Leonard Friedman

Government Reference Publication

Excerpt: In the fall of 1966 the Food and Drug Administration established an Advisory Committee on Protocols for Safety Evaluation. The first problem to be reviewed was the requirement for reproduction studies in the safety evaluation of pesticides and food additives, and the adequacy of the current methods involved. Reproduction studies are designed to give information on: (1) effects on male and female fertility, (2) effects during gestation on the mother and the fetus...

Read More
  • Cover Image

Guidelines of the Council on Environmental Quality for the Prepara...

By: Beatrice E. Willard

Government Reference Publication

Excerpt: This conference is naturally of vital concern to those of us on the Council on Environmental Quality, because it is with us that the responsibility resides for working with agencies to improve the process of environmental impact analysis. Therefore, I am glad to be here to share some thoughts with you about how to implement the CEQ Guidelines. I have demonstrated in my professional work as an ecologist for a decade and a half that the principles and processes ev...

Read More
  • Cover Image

Cumulative Impact

By: Gregory C. Pratt

Government Reference Publication

Excerpt: The terms ?cumulative? and ?cumulative effects? are becoming more widely used in environmental impact assessment. The popularity of the concept is understandable as our culture comes to recognize that solitary insults to the environment considered in isolation cannot capture the full effect of the problems now before us. But what exactly do we mean by the term ?cumulative??.

Read More
  • Cover Image

Methods for the Analysis of Intestinal Function

By: Carol T. Walsh

Government Reference Publication

Excerpt: The intestinal trdct is an organ of considerable complexity, comprising numerous tissue types and subserving multiple functions. The analysis of the physiology of this system has, therefore, involved, and continues to require, the application of research tools from many disciplines within the sciences. For the purposesof this conference, the following review will he restricted to the analysis of the primary function of the gastrointestinal tract, namely the proc...

Read More
  • Cover Image

Selection of Reproductive Health End Points for Environmental Risk...

By: David A. Savitz

Government Reference Publication

Introduction: In convast to cancer or cardiagsculdiseaser,e production is not a disease entity. Although this statement seems both obvious and simplistic, the fact that reproduction dersto a biologic and social proms as opposed to a specific pathologic entity bas pmfound implications for the scientist or policy maker inin reproductive risk assessment, In addition to the familiar methodological challenges that cohfront investigators of envimnmental influences on chronic d...

Read More
  • Cover Image

Carcinogenicity Evaluations and Ongoing Studies : The Iarc Databases

By: Harri Vainio

Government Reference Publication

Introduction: Chemicals, Carcinogens, and Hazards to Humans Estimates vary as to the number of chemicals that are produced In significant amounts. In 1980, the European Core lnvcntory IECDIN I listed about 34MX)chemical wbstances helicved to be on the European community market (I). Later, Shulze and Miicke (2) estimated that there were about 100,000 chemicals on the market within the European Community. Recently, it has been estimated on the basis of the U.S. Toxic Subst...

Read More
  • Cover Image

Chronic Bioassays of Chlorinated Humic Acids in B6C3F1 Mice

By: Susan Melchionne

Government Reference Publication

Excerpt: The occurrence of low molecular weight halogenated aliphatic and olefinic hydrocarbons in the environment and their potentially adverse human health effects has become the subject of intensive research during the past 15 to 20 years. The upsurge of research in this area was spurred by the demonstration of the carcinogenic activity of vinyl chloride (1,Z) and of other low molecular weight, halogenated, saturated and unsaturated hydrocarbons (3-6). These studies a...

Read More
 
1
|
2
|
3
Records: 1 - 20 of 45 - Pages: 



Copyright © World Library Foundation. All rights reserved. eBooks from World Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.