Assessment of Exposure

Indoors, indicative of a total flooding system outdoors requiring assessment of exposure of nearby hazards, involvement of other combustibles, wind effects and difficulty of extinguishment. 

Assessment of exposure to fume from welding and allied processes... 

Hazard characterization and delineation of dose-effect or dose-response relationships. 3. Assessment of exposure 4. Risk characterization... 

CFN (1992). Workplace atmospheres — Guidance for the assessment of exposure by inhalation to chemical agents for comparison with limit values and measurement strategy. EN 689. 

The identification of chemical agents and the data on workplace factors leads to the assessment of exposure, which can be done in three different stages that depend on the risk level for the worker and the type and amount ot data required ... 

The assessment of exposure brings together all the data and compares the results of this integration with the chosen OEL. It begins with an initial appraisal and continues with a basic survey and then a detailed one until it is confirmed either that exposure exceeds the limit value or that it is sufficiently below that limit. 

Skender L, Karacic V, Bosner B, et al. 1993. Assessment of exposure to trichloroethylene and tetrachloroethylene in the population of Zagreb, Croatia. Int Arch Occup Environ Health 65 S163-S165. 

LAMBE j (2002) The use of food consumption data in assessments of exposure to food chemicals using the application of probabilistic modelling. Proc Nutrn Soc. 61 11-18. 

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. 

Peech Cherewyk K. 2002. Methyhnercury bioaccumulation in zooplankton an assessment of exposure routes and accumulation in newly flooded reservoirs. MS thesis. University of Manitoba, Winnipeg, Canada, 90 p. 

The only information that provided an assessment of exposure of children and adolescents to hydrogen sulfide was that developed during the South Karelia Air Pollution Study (Mortilla et al. 1994b) however, these exposures were complicated by simultaneous exposure to other sulfur-containing compounds as well as particulates. Additional exposure information is needed from communities where only hydrogen sulfide exceeds background levels. 

Shurdut, B., Assessment of Exposures and Risks to Greenhouse Workers Applying a Chlorpyrifos-Based Insecticide to Ornamentals Using Conventional and Probabilistic Approaches, paper presented at the International Union of Pure and Applied Chemistry, 1994. 

Huel G, Boudene C, Jouan M, et al. 1986. Assessment of exposure to lead of the general population in the French community through biological monitoring. Int Arch Occup Environ Health 58 131-139. 

Ludersdorf R, Fuchs A, Mayer P, et al. 1987. Biological assessment of exposure to antimony and lead in the glass-producing industry. Int Arch Occup Environ Health 59 469-474. 

Abadin HG, Wheeler JS. 1993. Guidance for risk assessment of exposure to lead A site-specific, multi-media approach. In Hazardous Waste and Public Health International Congress on the Health Effects of Hazardous Waste. Princeton, NJ Princeton Scientific Publishing Company, Inc., 477-485. 

Assessment of Exposure-Response Functions for Rocket-Emission Toxicants (1998) Review of a Screening Level Risk Assessment for the Naval Air Facility at Atsugi, Japan (Letter Report) (1998)... 

A variety of units have been used for the assessment of exposures to ionizing radiation. The current international standard terminology is shown in Table 32.3. This chapter uses the new terminology exclusively this frequently necessitated data transformation of units from early published accounts into the currently accepted international terminology. 

The interplay of the processes of absorption, distribution, metabolism and excretion result in changes in concentration of the test chemical in different organs with time. With regard to the practical concerns of monitoring human exposure, the organ of interest is the blood. Blood can be considered a central compartment. Determining the concentration of the chemical in plasma gives one an assessment of exposure. Mathematical formulas are used to quantitatively describe this exposure. 

Lu Y, Yuan T, Wang W, Kannan K (2011) Concentrations and assessment of exposure to siloxanes and synthetic musks in personal care products from China. Environ Pollut 12 3522-3528... 

Guidance for assessment of exposure in US-EPA exposure assessments can be found in US-EPA s 1995 Guidance for Risk Characterization (US-EPA 1995). 

The major objective in the risk assessment of exposure to mixtures of chemicals is to establish or predict how the resulting toxicological effect might turn out. Will the toxic effect be determined by simple additivity of dose or effect, or will it deviate from additivity, either by an effect stronger or less than expected on the basis of additivity ... 

Although testing of the whole mixture as such seems to be the proper way to approach the risk assessment of exposure to that mixture, it will not provide data on combined actions and/or interactions between the individual components of the mixture. Even if the effect of the mixture is compared with the effects of each individual component at comparable concentrations, this will not allow a description of potential synergism, potentiation, or antagonism, and it is even doubtful that deviations from additivity can be concluded. This can only be achieved if dose-response curves are obtained for each of the single compounds. 

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