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Note for Guidance for Food Contact Materials
Page 96 of 126

Statement of safety requirements and any special precautions in handling reagents.
Statement of purity requirements of substance (obtainable from EC-JRC)
, internal
standard and any special requirements for solvent or reagent purity. Statement of primary
and diluted calibrant solutions which should have a concentration range to span the QM
or SML limit.

Normal laboratory apparatus can be assumed but any instrument or special piece of
apparatus or particular specification should be stated.

The minimum performance of chromatographic methods should be stated in terms of the
resolution of the substance to be determined from internal standard, solvent or other
components. Examples of columns found to be suitable should be given.

Statement of requirements for taking of representative samples of materials and articles
for analysis. For testing with simulants the guide to the selection of conditions and
methods of test is stipulated in an EN Method (see the document "Methods of analysis").

Statement in sufficient detail of how to carry out procedure which should include the
manner of preparation of calibration curves, evaluation of data, and final determination
graphically or by calculation.
As quantitative extraction from materials and articles can never be fully demonstrated the
method of standard addition should always be employed for calibration. For
determinations of substances in food simulants an internal standard should always be
employed for chromatographic procedures and calibration should be against blank food
simulant fortified with the substance in question.

The method of analysis must include details for confirmation of test results to be used in
cases where the measured QM or SML values have been found to exceed the limits
specified in Directive 2002/72/EC and subsequent amendments.
The principle behind the confirmation step is that the technique used is sufficiently
different from that first used, that it confers additional assurance of identity and level of
putative substance. Thus for example:

12 See "EU and National Authorities"