Person in charge : Hemanth MOGER (hemanthmoger090@gmail.com)
Scientific supervision : Jean RIOTTE (jean.riotte@ird.fr)
The analytical platform supports IFCWS collaborative projects and the environmental observatory by providing data on water and to a lesser extent, soil compositions. Another objective of the platform is to take care of the water and soil archiving in dedicated rooms, for future analysis on request. Analyses of water include :
- pH, conductivity
- Alkalinity
- Dissolved organic carbon
- Anions (fluoride, chloride, nitrate, phosphate, sulfate) with detection limit ~ 0.1µmol/L
- Cations (Sodium, Potassium, Calcium, Magnesium), with detection limit ~ 1µmol/L
- Silica, with detection limit ~ 1µmol/L
We also developped a new method to determine both nitrate and chloride in soil extracts by ion chromatography.
Equipment
- Ion chromatography Metrohm 861 with auto sampler 863 and partial loop injection system Dosino 800
- Total Organic Carbon analyser Shimadzu TOC-CSH with auto sampler ASI-V
- Titrator Mettler DL50 with auto sampler Rondolino
- spectrophotometer Hach
- spectrophotometer UV/VIS KNAUER
- pH meter and conductivimeter WTW
- water deionization system Millipore Elix
- water ultra pure system Millipore MilliQ Academic
- centrifuge Sigma
- balance Sartorius (max 420g, d=0.001g)
- precision balance Sartorius (max 220g, d=0.0001g)
Quality Management System
Traceability of the analytical process
Samples registration
Each sample is identified by a unique number, recorded both in a Logbook and in the IFCWS chemical Database.
Samples analysis
Samples analyses are organised by batch for each parameter. All chemicals, reagents, mother solutions and calibrations which are used in a batch are identified by a code. Balance and pipettes are verified for metrology.
Validation
Each batch is validated by regular measurements of CRM (Certified Reference Materials) :
- ION 915 (Environment Canada): low concentrations of anions and cations
- ION 96.4 (Environment Canada): high concentrations of anions and cations
- PERADE (Environment Canada): DOC, Silica
- Anions – WS (RTC): anions and phosphate
CRM monitoring (Z-Score):
Z-score is calculated according to the formula :
(x – V) / σ
with : x = lab value
V = certified value
σ = certified range of acceptance
Z-score = 0 : certified value
Z-score = [-1,+1] : certified range of acceptance
Blue bars = average of lab results with standard deviation range
Results
All the results are stored in the IFCWS chemical database, which comprises more than 15000 water samples.