Targeting assessment methodology

Present-day risk assessment methodologies have an increasing emphasis on physiologically based pharmacokinetics (PBPK) or toxicokinetic models and mode of action (MOA). Snch models have been developed to predict exposure levels in target tissues for a large number of agents. PBPK models are especially useful in the risk assessment context because they allow data to be extrapolated across species, dose levels, and routes of exposure. 

This new method is named SEEBALANCE. SEEBALANCE targets the adoption of life-cycle social data to the results of eco-efficiency analysis for a complete sustainability assessment methodology. It is a helpful tool in different fields for the evaluation of product or process alternatives. " ... 

See Appendix B for release assessment methodology and release targets... 

ABSTRACT The fire protection and Safety in urban property is a sensitive and important topic, even more so in the context of older buildings that tend to be more vulnerable. In this case, fire risk analysis needs to be carried out, in order to ascertain safety levels, weaknesses, and hence adequate risk mitigation measures. The application of the assessment methodology of fire risk proposed, MARIEE, can be of high interest in developing a classification that can be applied to new and old buildings or those that will be targeted for rehabilitation processes. 

The need for the implementation of target levels for air quality in industrial work rooms stems from different concerns. In addition to technological factors, the systematic design methodology, life cycle assessment, advances in air distribution methods, and increased integration with the process and... 

Measurement of exposure can be made by determining levels of toxic chemicals in human serum or tissue if the chemicals of concern persist in tissue or if the exposure is recent. For most situations, neither of these conditions is met. As a result, most assessments of exposure depend primarily on chemical measurements in environmental media coupled with semi-quantitative assessments of environmental pathways. However, when measurements in human tissue are possible, valuable exposure information can be obtained, subject to the same limitations cited above for environmental measurement methodology. Interpretation of tissue concentration data is dependent on knowledge of the absorption, excretion, metabolism, and tissue specificity characteristics for the chemical under study. The toxic hazard posed by a particular chemical will depend critically upon the concentration achieved at particular target organ sites. This, in turn, depends upon rates of absorption, transport, and metabolic alteration. Metabolic alterations can involve either partial inactivation of toxic material or conversion to chemicals with increased or differing toxic properties. 

The absorption efficiency term allows estimation of the effective dose or the amount of pollutant which crosses the membrane of the exposed tissue (e.g., the lung) and reaches a target organ (e.g., the liver). For many pollutants this type of metabolic data is not available and consequently 100% absorption is a common preliminary assumption in exposure assessments. For well-studied substances such as radionuclides, a methodology for calculation of target organ doses has been developed for bone marrow, lungs, endosteal cells, stomach wall, lower intestine wall, thyroid, liver, kidney, testes and ovaries as well as for the total body. 

Gene-targeted (knockout) mouse models provide one avenue for assessing the in vivo functional significance of particular proteins. A complementary approach is the expression of the protein of interest using transgenic methodology. There... 

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