Standardised methods

Hautfenne A, Pocklington WD, Wolfe JP. 1987. Determination of hexane residues in oils Results of a collaborative study and the standardised method. Pure Appl Chem 59(11) 1561-1570. 

Haslbeck and Holm, 2005), and the potential deposition of inorganic copper salts (Arias, 1999). Standardised methods have also been demonstrated to overpredict in situ release scenarios (Valkirs et al., 2003). Quoting Haslbeck and Holm with the current methods it will be difficult to interpret and predict release rate results and to estimate how reformulation of coatings or limits placed on release rates would impact the environment . Thus, it seems that further work is needed in order to optimise these methods. 

There are several publications detailing standard or officially recognized methods of fertilizer analysis. These include Official Methods of Analysis of AOAC International (Horwitz, 2000) Official and Standardised Methods of Analysis, published by the Royal Society of Chemistry (Watson, 1994) and Fertilisers - Methods of Analysis used in OEEC Countries (OEEC, 1952). There are also the EEC methods, which have been implemented in the UK by the Fertilisers (Sampling and Analysis) Regulations 1996 (Statutory Instrument (SI) 1996 No. 1342). The title page of the SI may be downloaded from the following website ... 

Two synthetic internal standards are used (nor-DCA and nor-CA) to perform an external standardisation method. Calibration curves for each compound are built, starting from known amounts of standards ranging from 0.02 pg to 0.2 pg. BA standards are prepared and analysed as described in below in section 5.4.5.3 Analytical, Procedure . 

An external standardisation method is employed to perform quantitative analysis. In the cited study, calibration curves for each compound are obtained by injecting amounts ranging from 0.08 to 10 nmol. The amount of injected standards is logarithmically proportional to the peak area. 

The Analytical Methods Committee s own compilation of official and standardised methods of analysis is widely used and respected within the analytical community. The importance of standardised formats for method documentation has been emphasised by the AMC s guidelines for achieving quality in trace analysis. They list 17 headings for inclusion in the documentation ... 

C.A. Watson, ed.. Official and Standardised Methods of Analysis, Royal Society of Chemistry, Cambridge, 3rd edn., 1994. 

Resano et al. [107] used LA-ICP-MS to fingerprint diamonds from different deposits. Nine elements were selected and the samples were classified by different methods. Different standardisation methods were studied and PLS outperformed other pattern recognition methods. In this particular application, the main aim was not predictive, in the typical sense, but discriminant (this is also termed discriminant-PLS). 

A somewhat paradoxical situation has arisen in more recent years because of the increased interest in comparative data and databases. Some of the pressure for better design data and the criticism of the standardised methods has been turned to a demand for very tightly standardised data. To be comparable, data in a database needs to be all produced in exactly the same way and the development of standards to offer a choice of method and several choices of conditions for the same property is not compatible with this need. Consequently, there has been a lobby for what might be termed extreme standards which are specifically intended to yield completely comparable data very efficiently, but possibly at the expense of other attributes. 

It should be noted that standardised methods may also be developed and tested by following a similar stepwise approach. In this case, the participants are given less freedom in term of method development since they are requested to apply a common procedure (e.g. leaching or extraction procedure) (Quevauviller et al., 1993a Quevauviller, 1998a). 

Egeler P, Rombke J, Meller M, Knacker T, Nagel R. 1999. Bioaccumulation test with tubi-ficid sludgeworms in artificial media—development of a standardisable method. Hydrobiologia 406 271-280. 

Both variolin B and its 5-deoxy derivative 19 (Scheme 6.1 Part 2) have shown promise in pharmacokinetic and in vivo studies. These compounds have been shown to have long terminal half-lives and low normal cell toxicity, however the 5-deoxy derivative demonstrated better Cmax, plasma clearance and terminal plasma half-life.318,319 Both are effective against human lung carcinoma cell lines in nude mice.104 The deoxy-variolin B showed growth inhibitory activity against human leukemic cell lines.105 A standardised method for liquid chromatography-mass spectrometry (LC-MS)/MS analysis of plasma has been developed to monitor the results of the in vivo studies.320... 

For standardised methods the calibration curve is always produced with a pure-element solution. Hence, interferences have to be considered and eliminated, leading to time consuming checks of variable parameters such as matrix effects, anion or cation influences or interferences caused by acids. 

The suitability of this method to determine compliance with the legislation has been discussed within CEN/TC194/SC1 where it was suggested that the colorimetric method should be used only for screening purposes and that PAA levels above 2 pg/kg (as aniline) should be verified using a specific method. As a result a standardised method of analysis is required to determine the migration of individual PAAs from food contact materials and articles, to ensure compliance with the legislation. 

In carbon materials, active surface sites only represent a fraction of the total surface area, called active surface area (ASA). Knowledge of the nature and concentration of the active sites is of paramount importance for a better understanding of the kinetics involved in heterogeneous gas-solid reactions. However, although ASA reveals interesting information about the sample, there is a need for a reliable and standardised method for its estimation. The aim of this work is to compare ASA determination by the usual methods (i.e., gravimetry, TPD) with another method, which is based on pressure measurements in order to perform an oxygen chemisorption isotherm (OCI). The results showed that the OCI method seems to be a valuable and alternative method for ASA determination, as it avoids the main potential source of errors Inherent in the usual methods. 

Whilst most of these standardised methods must be performed within laboratories, some of them (mainly probe techniques such as those for measuring for instance pH, conductivity, temperature, turbidity, and dissolved oxygen) may be readily adapted for use in the field and can be used for making in-situ measurements. Others methods have been automated with standardized systems, based on FIA or CFA systems. This... 

In accordance with Article 7a of the WHG, the AbwV (Ordinance on Requirements for the Discharge of Wastewater into Waters - Wastewater Ordinance) has been divided into a general framework section, an annex (to Article 4) with analytical methods for parameter determination and sector-specific appendices, including requirements for 53 wastewater sectors [3], Minimum requirements to be stipulated when granting a permit to discharge wastewater are described, analysis and measurement techniques are specified in the annex and sector-specific requirements in the appendices refer to the analysis and measurement techniques specified in the annex. Article 4 of the AbwV, in conjunction with the annex, lists the analysis and measurement procedures that are to be used to determine the parameters defined in the appendices. Paragraph 2 emphasises that for individual cases other equivalent procedures may be required if compliance with the requirements specified in the ordinance is to be ensured [9]. All analysis and determination procedures are standardised methods (DIN, CEN, ISO). 

All analysis and measurement procedures cited in the AbwV and AbwAG are standardised methods, either by DIN, ISO or CEN. Development and standardisation of biotests for emission control are carried out by national working groups on biotests (DIN), resulting in DIN standard protocols since 1976. Representatives of federal government, the Lander, industry and universities are usually present in the national working groups. 

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