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Participants worldwide

PT Schemes


General Procedure
The participating laboratories receive 4 dried sediment samples of a fraction < 0.5 mm every three months. They analyse the samples according to their own procedures and for those compounds they are interested in. The results of the determinations are collected and processed at Wageningen University and published every three months under code names. Member laboratories are informed of the results in the third week after the deadline. WEPAL will not comment on results unless asked to do so.

Elements Determined
Determinations are currently made for the following elements and components. New analytes may be added by request of participants.

Quarterly Reports
All individual results are published in a quarterly report. This report is sent to participants within 3 weeks after the deadline for results.
... read more about quarterly reports.

Annual Report
In addition to quarterly publication of the analytical results, an annual report is issued every year.
... read more about annual reports.

Method Indicating Code (MIC)
In the reports behind all the results details of the analytical procedures used by the individual participants are indicated by a Method Indicating Code (MIC), This indicates the method of extraction or digestion, clean-up procedure and separation technique and at the end method of detection of the analyte in the extracts or digests. In this way it is possible for all participants to compare the results of their analytical procedures more specifically with the results of other participants. This could be a further valuable tool in judgement of the individual results.

Follow the link for an overview of the participation fees.