Routine chemical analysis

Residual heavy metals and organo-chlorine pesticides represent two well-known pollution problems. Sensitive and accurate analysis is required to enable the distribution and level of a pollutant in the environment to be assessed and routine chemical analysis is important in the control of industrial effluents. 

This paper describes the use of statistical techniques to improve precision in routine chemical analysis at a modest extra cost and to measure the precision of such analyses. 

To provide optimum data in routine chemical analysis, the analytical method must meet four criteria. The first two are... 

Most laboratories involved in large-scale routine chemical analysis of mainstream smoke aim to produce results showing relative yields so that valid brand comparisons can be made. It is therefore essential to maintain careful standardization of all procedures,... 

Colorimeter. An instrument for routine chemical analysis. Compounds or ions which absorb light in the visible part of the spectrum (400 to 800 nanometers) or which are convertible by specific reagents to such compounds can be analyzed with a colorimeter. The instrument typically incorporates an incandescent light bulb as light source, filters to separate the spectral region, a cuvette to contain the sample solution, and a photometer. See also Colorimetry,... 

The concepts of quality management (QM) and QA in analytical laboratories were developed primarily to harmonize the world market and in connection with the globalization of the world s major trading zones they have now been formally established in relevant directives and standards—formerly ISO 25 and EN 45001, more recently ISO/IEC17025. The requirements of these standards have become widely accepted as market-regulating tools by both the chemical industry and independent laboratories for routine chemical analysis. At present they are extensively implemented in the form of accreditation, a universally accepted process by which an authoritative body at national or international level gives formal recognition that a laboratory or a person is competent to carry out specific tasks. 

A discussion of quality control applied to routine chemical analysis is by H. E. MacColl Chemistry and Industry, December 9th, 1944, page 418. 

In spring 2004 the Daphnia Toximeter deployed at the RIZA monitoring station alongside the River Meuse in Keizersveer (NL) recorded several alarms. Routine chemical analysis did not reveal the identity of the offending compound(s). It took sophisticated chemical analyses, a combination of HPLC-DAD and Q-TOF MS techniques, to identify the so-far unknown contaminant as 3-cyclohexyl- 1,1-dimethylurea. The maximum concentration of this compound in the River Meuse at the time of the alarm was estimated to be 5 ig/L. The response of the Daphnia to this compound was later confirmed... 

For several decades, mass spectrometers were used primarily to determine atomic masses and isotopic ratios. Now they are applied to a large variety of chemical problems and low resolution mass spectrometers are used for routine chemical analysis. For exanq>le, a modem mass spectrometer can easily distinguish between species such as and... 

The most effective way to identify the different electrode systems has proved to be application of potentiostatic polarization followed by X-ray diffraction analysis of the obtained anodic deposit. Employing combined XRD and routine chemical analysis... 

In any child presenting with obstructive symptoms by radiolucent stones the possibility of APRT deficiency should be considered, especially if the patient has a normal content of urate in serum and urine. When uric acid stones are identified by routine, chemical analysis, then additional confirmatory tests should be performed since there is no possibility of distinguishing between uric acid and DOA in a simple chemical analysis. Only a crystallographic method as for instance X-ray diffraction or infrared spectrophotometry detects the DOA compound (Fig. 10). As already mentioned, these stones are grayish blue and more friable than uric acid. Confirmation of the diagnosis provides the measurement of the APRT activity in erythrocyte hemolysates (3). All other members of a family should be screened for the APRT deficiency, because some might only have asymptomatic crystalluria. 

The routine chemical analysis for the quality control of compost and soil will not be suitable to detect (unknown) metabolites which are harmful to the environment. Bioassays will be necessary to supplement other analyses and to complete the information about the environmental behaviour of biodegradable polymers. This requirement is already expressed in the inclusion of mandatory bioassays in the relevant standards for compostable products. 

The inclusion of mandatory ecotoxicity tests in the most relevant standards is already realised (Table 4.1). The extent of the investigations may differ between the standards, but they share the same intention the detection of negative influences, which are not covered by the routine chemical analysis. Because of lack of practical experience, especially about how to deal with complex matrices like compost in conventional bioassays, not many mandatory methods are currently listed in the German and in the European standard. Nevertheless, an option to include more or maybe specially adapted methods is kept in the EN 13432 [3]. 

Routine chemical analysis (products and raw materials) Crushing strength... 

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