Seawater - WEPAL-QUASIMEME

Proficiency tests

Participation in our seawater programmes (AQ) is open to all laboratories. The normal validated methods and procedures of each laboratory should be used to analyse the test materials. Laboratories are requested to fill in method information codes (MIC) for each determinand. This allows laboratories to review the range and similarity of the methodologies used.

Determinand Group Sample Type Exercise
Nutrients High salinity seawater AQ1
Nutrients Estuarine and low salinity seawater AQ2
Metals High and low salinity seawater AQ3
Mercury High and low salinity seawater AQ4
Halogenated organics High and low salinity seawater AQ5
Volatile organics High salinity seawater AQ6
Pentachlorophenol High salinity seawater AQ7
Pesticides High and low salinity seawater AQ8
Chlorophyll and Pheopigments Estuarine and fresh water AQ11
Organotins High salinity seawater AQ12
PAHs High and low salinity seawater AQ13
DOC High and estuarine seawater AQ14
Ocean acidification (total alkalinity, DIC and pH) High and low salinity seawater AQ15
Polar/nonpolar compounds Sampler(s) DE13
Microplastics Diverse matrices DE17
PFAS (Sea)water DE18
Pharmaceuticals (Sea)water DE19

General information

  • Seawater samples are mainly prepared from seawater originating from the North Sea, Atlantic Ocean, the Baltic sea and estuarine water to cover water samples with varying salinity. For chlorophyll samples sometimes freshwater is used.
  • Water samples are filtered using a 0.45µm / 0.2µm double membrane filter.
  • The water samples are stable for the period of the test when stored properly.
  • All seawater samples are prepared in bulk and tested for its homogeneity where relevant.
  • Use your normal validated methods and procedures to analyse the test materials.
  • Some of the PT samples (AQ5; AQ7; AQ8; AQ12 and AQ13) need to be spiked in your own laboratory because of stability issues.
  • New determinands can be added to these programs on request.
  • Reportscontain all data reported under strict confidentiality, including Z-score plots and method information of methods used.

    Determinands

    The list below shows the typical determinands for the seawater, estuarine water and freshwater Programme. For a list of determinands which are under the scope of accreditation please check here.

    Analyte group Typical analytes Exercise
    Brominated flame retardants BDE28, BDE47, BDE49, BDE66, BDE85, BDE99, BDE100, BDE126, BDE153, BDE154, BDE183, BDE209, TBBP-A, Dimethyl-TBBP-A, a-HBCD, b-HBCD, g-HBCD, Total HBCD, BTBPE, DBDPE, HBBz, EHTBB, EHTEBP DE13
    Dissolved Organic Carbon DOC AQ14
    Metals Arsenic, Boron, Cadmium, Chromium, Cobalt, Copper, Iron, Lead, Magnesium, Manganese, Mercury, Nickel, Silver, Strontium, Thallium, Tin, Vanadium, Uranium, Zinc AQ3, AQ4
    Microplastics Total number of particles, Total mass of particles DE17
    Nutrients Ammonia, Nitrate, Nitrite, Phosphate, Silicate, TOTAL-N, TOTAL-P, TOxN AQ1, AQ2
    Ocean acidification Dissolved Inorganic Carbon, Total Alkalinity, pH AQ15
    OPs&Herb Aclonifen, Alachlor, Atrazine, Atrazine-desethyl, Azinphos-ethyl, Azinphos-methyl, Bifenox, Bifenthrin, Chlorfenvinphos, Chlorpyrifos, Chlotianidin, Coumaphos, Cypermethrin, Deltamethrin, Demeton, Diazinon, Dichlorvos, Dicofol, Dimethoate, Diuron, Esfenvalerate, Fenchlorophos, Fenitrothion, Fenthion, Glyphosate, Imidacloprid, Irgarol-1051, Isoproturon, Malathion, Nicosulfuron, Omethoate, Parathion-ethyl, Parathion-methyl, Permethrin, Quinoxyfen, Simazine, Terbutryn, Terbuthylazine, Thiacloprid, Thiamethoxam, Triazophos, Triclosan AQ7
    Organometals Dibutyltin(DBT), Diphenyltin(DPhT), Monobutyltin(MBT), Monophenyltin(MPhT), Tributyltin(TBT), Triphenyltin(TPhT) AQ12
    PCBs&OCP a-HCH, b-HCH, g-HCH, d-HCH, HCB, HCBD, Aldrin, Dieldrin, Endrin, Isodrin, pp'-DDD, pp'-DDE, op'-DDT, pp'-DDT, Endosulphan-I, Endosulphan-II, Pentachlorobenzene, 1-2-3-TCB, 1-2-4-TCB, 1-3-5-TCB, Trifluralin, PCB28, PCB31, PCB52, PCB101, PCB105, PCB118, PCB138, PCB138+PCB163, PCB153, PCB156, PCB180, Heptachlor, Heptachlorepoxide, Pentachlorophenol AQ7, DE13
    Perfluorinated alkyl substances PFOS, PFBA, PFPeA, PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUnDA, PFDoA, PFTrDA, PFTeDA, L-PFBS, L-PFHxS, L-PFHpS, PFOSA, PFDS, PFODA, GenX, F-53B, PFBSA, PFHxSA, NMeFOSAA and NEtFOSAA DE18
    Pigments Chlorophyll-a, Chlorophyll-b, Chlorophyll-c, Pheopigments, Chlorophyll-a (Corr), Chlorophyll-a (HPLC), Chlorophyll-b (HPLC), Chlorophyll-c (HPLC) AQ11
    Polycyclic aromatic hydrocarbons Acenaphthene, Acenaphthylene, Anthracene, Benzo[a]anthracene, Benzo[a]pyrene, Benzo[b]fluoranthene, Benzo[e]pyrene, Benzo[k]fluoranthene, Benzo[g,h,i]perylene, Chrysene, Dibenzo[ah]anthracene, Fluorene, Fluoranthene, Indeno[1,2,3-cd]pyrene, Naphthalene, Phenanthrene, Pyrene, Total petroleum hydrocarbons AQ13, DE13
    Salinity Salinity, Salinity indicative AQ1, AQ2
    VOCs Benzene, Carbon-tetrachloride, Chlorobenzene, Chloroform, 2-chlorotoluene, 4-chlorotoluene, 1,2-dichlorobenzene, 1,3-dichlorobenzene, 1,4-dichlorobenzene, 1,1-dichloroethane, 1-2-dichloroethane, 1,1-dichloroethene, cis-1,2-dichloroethene, trans-1,2-dichloroethene, Dichloromethane, 1,2-dichloropropane, Ethylbenzene, Isopropylbenzene, n-Propylbenzene, Styrene, tert-bytylbenzene, 1,1,1,2-tetrachlorethane, Tetrachloroethene, Trichlorethene, 1-1-1-trichloroethane, 1-1-2-trichloroethane, 1,3,5-trimethylbenzene, Toluene, m+p-Xylene, o-Xylene AQ6

    Reference materials

    Samples of previous proficiency tests are sold as reference materials. Available materials can be selected and ordered in our webshop. In our webshop it is also possible to request a quotation. Participants of our proficiency tests are entitled to a discount.