ACES Proficiency Tests

Department of Environmental Science, Stockholm University

Proficiency tests for environmental analysis

The Department of Environmental Science at Stockholm University – ACES – organizes proficiency tests with an environmental focus for water laboratories performing chemical, physical and sensory analyses.

See our program below.

news

2 February 2026

ACES 2026-1 Dispatch

The samples for ACES 2026-1 Metals and trace elements + Sludge were dispatched on February 2.

3 December 2025

ACES 2025-4 Final report

The final report for ACES 2025-4 Paper industry wastewater has been published. It can be downloaded from the Reports-page or from the link in the relevant round further down on this page.

Program 2026

Metals and trace elements + Sludge

Part A: Potable water, spiked
Ag, Al, As, B, Ba, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sb, Se, Si, Sn, Sr, U, V, Zn

Part B: Municipal wastewater, treated, spiked
Ag, Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, Sn, Zn

Part C: Digested sludge
dry solids, dry fixed solids, pH, alkalinity, NH4N, Ntot

Part D: De-watered sludge
dry solids, dry fixed solids

2026-1

Municipal wastewater

Part A: Municipal wastewater, treated
BOD7, CODCr, CODMn, TOC, DOC, conductivity, pH, alkalinity

Part B: Municipal wastewater, treated, spiked
suspended solids, fixed ignition residue

2026-2

Nutrients

Part A: Eutrophic recipient
NO2N, NO3N, NO2,3N, NH4N, Ntot, PO4P, Ptot, Si, colour, pH, conductivity, BOD7, suspended solids, fixed ignition residue

Part B: Municipal wastewater, treated
NO2N, NO3N, NO2,3N, NH4N, Ntot, PO4P, Ptot, Si, colour, pH, conductivity

2026-3

Ion Balance + Odour & Taste

Part A: Potable water
colour, transmittance, conductivity, pH, turbidity, alkalinity, Ca+Mg, hardness, Ca, K, Mg, Na, chloride, fluoride, sulphate, CODMn, TOC, DOC, Ntot, Ptot, possible spiked sample pair for NO2,3N and NH4N

Part B: Lake water
colour, transmittance, conductivity, pH, turbidity, alkalinity, Ca+Mg, hardness, Ca, K, Mg, Na, chloride, fluoride, sulphate, CODMn, TOC, DOC, chlorophyll

Part C: Odour in water
Part D: Taste in water

2026-4

Paper industry wastewater

Part A: Paper industry wastewater, treated
BOD7, CODCr, TOC, DOC, conductivity, pH, alkalinity, Na, chloride, sulphate, Ntot, Ptot, possible spiked sample pair for NO2,3N and NH4N

Part B: Paper industry wastewater, treated, spiked
suspended solids, fixed ignition residue, susp70 (if enough interest)

2026-5

Costs

Metals and trace elements
2026-1 part A and B
Registration fee 4200 SEK/part + 410 SEK/each reported parameter

Odour and taste
2026-4 part C and D
3400 SEK for odour. 2400 + 480 SEK for both odour and taste.

Other rounds
Registration fee 3400 SEK/part + 480 SEK/each reported parameter