Assessment of data

To satisfy government agencies, instruments need to be adequately tested, calibrated, and/or standardized according to documented procedures. Current GLP standards state that equipment used in the generation, measurement, or assessment of data and equipment used for facility environmental control must be of appropriate design and capacity to function according to the protocol and shall be suitably located for operation, inspection, cleaning, and maintenance. 

This chapter will discuss the evaluation of dust explosion potential at various manufacturing operations in three Army Ammunition Plants. The assessment of data from each plant will be presented in detail. 

Zuppa et al.60 have used SOMs in the assessment of data from an electronic nose. Six chemicals—water, propanol, acetone, acetonitrile, butanol, and methanol—were presented at varying concentrations to a 32-element conducting polymer gas sensor array. The output was used to train a group of SOMs, rather than a single SOM, to avoid the problems of parameter drift. One SOM was associated with each vapor, and with suitable use of smoothing filters, the SOM array was found to perform effectively. 

The advent of analytical techniques capable of providing data on a large number of analytes in a given specimen had necessitated that better techniques be employed in the assessment of data quality and for data interpretation. In 1983 and 1984, several volumes were published on the application of pattern recognition, cluster analysis, and factor analysis to analytical chemistry. These treatises provided the theoretical basis by which to analyze these environmentally related data. The coupling of multivariate approaches to environmental problems was yet to be accomplished. 

A comprehensive Manual for Investigation of HPV Chemicals is available (OECD 2004). The Manual describes procedures, including the use of electronic discussion groups and the online HPV database data gathering and testing SIDS, the SIDS plan, and the SIDS Dossier data evaluation initial assessment of data (guidance for assessing the hazards of chemical substances to man and the environment) preparation of the SIAR and SIAP and post-SIDS work. 

As a tool to make mutual acceptance of risk assessments possible, OECD has developed the concept of Good Laboratory Practice (GLP). The OECD Principles of GLP are an integral part of the 1981 OECD council decision on the Mutual Assessment of Data (MAD) in the Assessment of Chemicals (revised 1997, Section 2.2.2). MAD also harmonizes procedures of GLP compliance monitoring, ensuring that preclinical safety studies are carried out according to the principles of GLP and that countries can have conftdence in the quahty and rigor of safety tests. 

Equipment used for the generation, measurement, or assessment of data shall be adequately tested, calibrated, and/or standardized."... 

Consequently, the aims in this chapter are to critically examine the available literature on the flavonoid composition of foods and to establish a food flavonoid database, which can be continually expanded as more information becomes available. By using predetermined selection criteria to ensure critical assessment of data quality, the intention is to provide researchers with an improved resource for use in studies exploring the relationships between flavonoid intake and health as well as highlighting important food groups where flavonoid content data are currently lacking. 

The evaluation of dose-response relationships is a critical component of hazard characterization (OECD, 1989 ECETOC, 1992 US , 1997a IPCS, 1999). Evidence for a dose-response relationship is an important criterion in establishing a toxic reproductive effect. It includes the evaluation of data from both human and laboratory animal studies. Because quantitative data on human dose-response relationships are infrequently available, the dose-response evaluation is usually based on the assessment of data from tests performed using laboratory animals. However, if data are available in humans with a sufficient range of doses, dose-response relationships in humans can also be evaluated. 

Computer systems are composed of electronic equipment used in the generation, measurement or assessment of data. 

Group D elements describe the procedures that will be used for the assessment of data quality and usability. Properly conducted laboratory data review, verification, and data validation establishes whether the obtained data are of the right type, quality, and quantity to support their intended use. 

Understanding how the calculations are conducted is important for the assessment of data quality, as the recalculation of results from raw data may disclose an undetected laboratory error. In this chapter, we will review common internal and external standard calculations. 

A stepwise approach to DQA identifies different tasks that may be performed by individuals with different expertise. For example, a less experienced chemist may verify the data package content (Step 2), whereas a more experienced chemist may perform data evaluation (Step 3). For a statistical data collection design, a statistician may be involved in the assessment of data relevancy (Step 6). A database manager may be involved at several steps if the EDDs are part of laboratory deliverables and if completeness is calculated. 

Assessment of data quality Environmental hazard analysis... 

These observations underline the fact that assessments of data from nonclinical toxicological experimentation should be undertaken with full knowledge of the involved uncertainties, weaknesses, and difficulties (Gad, 2006). 

Organisation for Economic Co-Operation and Development [OECD], 2007. Manual for investigation of HPV chemicals, chapter 4 initial assessment of data. Paris (France) Organisation for Economic Co-Operation and Development, http //www.oecd.org/ document/7/0,2340,en 2649 34379 1947463 l l l l,00.html. 

Metabolic activation systems—such as microsome-, cell-, and host-mediated assays—have been included in mammalian cell mutagenesis systems. Microsome-mediated assays have been used to detect many chemicals, including nitrosamines, polycyclic hydrocarbons, aflatoxins, and vinyl chloride. Cell-mediated assays seem to be a better indicator of in vivo metabolic pathways. Microsome-mediated assays seem suitable for general screening of chemicals, and cell-mediated assays are more valuable in the assessment of data. 

C. Independent Assessment of Data Quality and Development of Predictivity Criteria... 

Assessment of data quality and development of predictivity criteria... 

Once an assessment has determined that the data indicate human risk potential, the next step is to perform a quantitative evaluation. Here, dose-response data from human and animal reproductive and developmental toxicity studies are analyzed to select LOAELs and NOAELs or to calculate a BMD. The assessment should use quantitative human dose-response data if the data span a sufficient range of exposure. Because data on human dose-response relationships are rarely available, the dose-response evaluation is usually based on an assessment of data from tests performed in experimental animals. 

This example illustrates that had the toxicity of vinyl chloride been evaluated before workers were exposed, the 100-200 people who have had or are likely to suffer fiver cancer would not have done so. Tests in experimental animals and possibly also in in vitro systems could have alerted manufacturers to the dangers. More recent assessments of data from animal studies reveal the risk, although they overestimate the actual risk from reported cases (see pp. 307-8). 

Love Canal also contributed strongly to the development of risk assessment methodologies since the Superfund Act required that determinations of clean-up levels be made based on a scientific assessment of data on the toxicity of contaminants found at the hazardous waste sites and the potential for exposure to those contaminants. In light of the limitations in available knowledge, new approaches had to be devised to answer the question of how clean is clean The methodology that was adopted married scientific data to value judgments about acceptable risk and margins of safety. This approach remains in use. 

An index based on the sum or average of bioassay end-points is the simplest to devise. In some instances it may be desirable to combine tests of acute lethality with sublethal tests in order to include a spectrum of organisms and/or responses. Indices are easier to construct if toxicity end-points are first translated into toxic units. The numerical values then can be summed like the chemical properties of a sample. An alternative would be to classify results on an ordinal scale (e.g. 0-10) based on the observed severity of effect. The approach is more subjective, but at least it incorporates expert judgement that should enter the assessment of data at some point. A ranking scale allows any kind of environmental measurement to be included in the index. 

The use of computerized systems by test facilities for the generation, measurement, or assessment of data is nowadays consolidated and computerized systems are fully integrated into the in vitro method. It is essential that for regulatory applications computerized systems are developed, validated, operated, and maintained in accordance with the OECD Consensus document No. 10 on The application of the principles of GLP to computerised systems [13] and specific guidance documents [14, 15]. 

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