Announcement for Inter-laboratory Comparison on Arsenic and Ammonia Nitrogen in Water 2022

We hereby announce the 4th Inter-laboratory Comparison on Water Quality Analysis, which is focused on the Proficiency Testing of Arsenic and Ammonia Nitrogen in Water. This activity is open to academic, regulatory as well as commercial laboratories world-wide, especially those from developing and emerging countries. The organizers of this project are CAS-TWAS Centre of Excellence for Water and Environment (CAS-TWAS CEWE) and Water Quality Analysis Laboratory, which both are established at the Research Center for Eco-Environmental Sciences (RCEES), Chinese Academy of Sciences (CAS). This project is supported by the Certification and Accreditation Administration of the People’s Republic of China(CNCA) and the Alliance of International Science Organizations(ANSO).

A draft report will be available at the end of February 2023, and the final report will be available to the participants by March 2023. All the participants who have contributed to the results will receive a certificate of participation in the activity.
We encourage all laboratories working in this field to participate and assess their analytical performance. To do this, participants are requested to completely fill out the Registration Form and mark the desired samples that you intend to determine. 

Test Samples 
The test samples for Arsenic are in concentrations of 75.0-250μg/L with 1% nitric acid as matrix. 

The test samples for Ammonia Nitrogen are in concentrations of 2.50-25.0mg/L with H2O as matrix.

The samples will be distributed by an international courier service to the participating laboratories.
Please Note:
In order to avoid delay or retention of the samples at customs, please inform us if there are import restrictions in your country for any of the samples. 
Instructions for analysis and reporting
Further detailed instructions and reporting forms will be sent by e-mail simultaneously with the dispatch of the samples in October  2022. 

In short, the participating laboratories should:
.use your own standard operation procedures for pre-treatment and instrumental determination
.use your own reference standards for identification and quantification 
.report one single concentration for each testing sample in each water matrix 
.report limits of determination for all measured analytes 
Time Schedule 

Participation Fee
The participation fee for any combination of the analytes in one item is free.

All recipients of this invitation are sincerely welcome to participate in the Inter-laboratory Comparison, and are encouraged to spread the activity to possibly interested laboratories!
Co-ordinating Group

E-mail Address
For all enquiries by e-mail, please use

Postal Address
Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences
18# ShuangQing Road, Haidian District, Beijing, P.R.China, 100085

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