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Full-Text Articles in Physical Sciences and Mathematics
Overview Of Data And Conceptual Approaches For Derivation Of Quantitative Structure-Activity Relationships For Ecotoxicological Effects Of Organic Chemicals, Steven P. Bradbury, Christine L. Russom, Gerald T. Ankley, T. Wayne Schultz, John D. Walker
Overview Of Data And Conceptual Approaches For Derivation Of Quantitative Structure-Activity Relationships For Ecotoxicological Effects Of Organic Chemicals, Steven P. Bradbury, Christine L. Russom, Gerald T. Ankley, T. Wayne Schultz, John D. Walker
Steven P. Bradbury
The use of quantitative structure–activity relationships (QSARs) in assessing potential toxic effects of organic chemicals on aquatic organisms continues to evolve as computational efficiency and toxicological understanding advance. With the everincreasing production of new chemicals, and the need to optimize resources to assess thousands of existing chemicals in commerce, regulatory agencies have turned to QSARs as essential tools to help prioritize tiered risk assessments when empirical data are not available to evaluate toxicological effects. Progress in designing scientifically credible QSARs is intimately associated with the development of empirically derived databases of well-defined and quantified toxicity endpoints, which are based on …
Predicting Modes Of Toxic Action From Chemical Structure: Acute Toxicity In The Fathead Minnow (Pimephales Promelas), Steven P. Bradbury, Christine L. Russom, Steven J. Broderius, Dean E. Hammermeister, Robert A. Drummond
Predicting Modes Of Toxic Action From Chemical Structure: Acute Toxicity In The Fathead Minnow (Pimephales Promelas), Steven P. Bradbury, Christine L. Russom, Steven J. Broderius, Dean E. Hammermeister, Robert A. Drummond
Steven P. Bradbury
In the field of aquatic toxicology, quantitative structure-activity relationships (QSARs) have developed as scientifically credible models for predicting the toxicity of chemicals when little or no empirical data are available. In recent years, there has been an evolution of QSAR development and application from that of a chemical-class perspective to one that is more consistent with assumptions regarding modes of toxic action. The objective of this research was to develop procedures that relate modes of acute toxic action in the fathead minnow (Pimephales promelas) to chemical structures and properties. An empirically derived database for diverse chemical structures of acute toxicity …
Ecological Risk Assessment For Chemical Stressors: Challenges In Predictive Ecotoxicology Research, Steven P. Bradbury
Ecological Risk Assessment For Chemical Stressors: Challenges In Predictive Ecotoxicology Research, Steven P. Bradbury
Steven P. Bradbury
Environmental management decisions are increasingly based on the results of ecological risk assessments that require data and models to establish the likelihood of adverse ecological effects that may occur or are occurring as a result of exposure to one or more stressors .. Research to support ecological risk assessments for chemical stressors must include a predictive capability.. The great number of chemicals, species and habitats (exposure conditions) associated with prospective and retrospective management decisions precludes the use of empirical testing as the sole means to fill data gaps .. Therefore, strategic laboratory and field testing must be undertaken in the …
Quantitative Structure-Activity Relationships And Ecological Risk Assessment: An Overview Of Predictive Aquatic Toxicology Research, Steven P. Bradbury
Quantitative Structure-Activity Relationships And Ecological Risk Assessment: An Overview Of Predictive Aquatic Toxicology Research, Steven P. Bradbury
Steven P. Bradbury
In the field of aquatic toxicology, quantitative structure-activity relationships (QSARs) have developed as scientifically credible tools for predicting the toxicity of chemicals when little or no empirical data are available. A fundamental understanding of toxicological principles has been considered an important component to the acceptance and application of QSAR approaches as biologically relevant in ecological risk assessments. As a consequence, there has been an evolution of QSAR development and application from that of a chemical-class perspective to one that is more consistent with assumptions regarding modes of toxic action. In this review, techniques to assess modes of toxic action from …
Predicting Modes Of Toxic Action From Chemical Structure: An Overview, Steven P. Bradbury
Predicting Modes Of Toxic Action From Chemical Structure: An Overview, Steven P. Bradbury
Steven P. Bradbury
In the field of environmental toxicology, and especially aquatic toxicology, quantitative structure activity relationships (QSARs) have developed as scientifically-credible tools for predicting the toxicity of chemicals when little or no empirical data are available. A basic and fundamental understanding of toxicological principles has been considered crucial to the continued acceptance and application of these techniques as biologically relevant. As a consequence, there has been an evolution of QSAR development and application from that of a chemical-class perspective to one that is more consistent with assumptions regarding modes of toxic action. The assessment of a compound’s likely mode of toxic action …
Introduction: Structural Properties For Determining Mechanisms Of Toxic Action, Steven P. Bradbury, Robert L. Lipnick
Introduction: Structural Properties For Determining Mechanisms Of Toxic Action, Steven P. Bradbury, Robert L. Lipnick
Steven P. Bradbury
The U.S. Environmental Protection Agency (EPA), under a variety of Federal legislation, is charged with the responsibility of assessing the hazards of chemicals to human health and the environment. In some cases EPA incorporates predictive techniques in its decisionmaking processes. In the context of some statutes, predictive toxicological methods can be cost-effective components in an overall approach for prioritizing chemicals for in-depth toxicological investigation. Predictive approaches are also used where empirical toxicological data are either unavailable or not required under a specific statute. For example, under Section 5 of the Toxic Substances Control Act (TSCA), EPA's Office of Toxic Substances …
Polar Narcosis In Aquatic Organisms, Steven P. Bradbury, Richard W. Carlson, Tala R. Henry
Polar Narcosis In Aquatic Organisms, Steven P. Bradbury, Richard W. Carlson, Tala R. Henry
Steven P. Bradbury
The majority of industrial organic chemicals lack identifiable structural characteristics that result in specific biological activity. These nonpolar-nonelectrolytes are acutely toxic to aquatic organisms via a nonspecific mode of action termed narcosis. The toxicity of industrial chemicals eliciting nonpolar narcosis can be reliably predicted by log P (baseline toxicity models). Using single chemical and joint toxic action models, several research groups have reported classes of polar compounds (for example, esters, phenols, and anilines) that elicit a narcosis-like syndrome; however, they are more acutely toxic than what is predicted using baseline toxicity models. An assessment of rainbow trout (Salmo gairdneri) in …