Priority substances Classification and monitoring

Good chemical status To achieve good chemical status, values of all priority substances that are emitted to the water body must be below limit values in – water – sediments – biota

EQS Under development: – EQS for water and sediments – QS for biota

While waiting for EQS: Norway are using limit values in freshwater and coastal water for – yearly mean value defined for 33 of 33 – maximum value defined for 18 of 33

Threshold values in sediments and biota Norway are using threshold values in sediments in coastal water. – defined for 20 of 33 In marine biota, values are defined for 8 substances – from 1 to 5 species of marine biota per substance (periwinkle, seaweed, blue mussels, cod liver, muscle of flounder, cod or herring)

Basis for limit values Current limits are based on risk of ecological effects. Origin is a 5-class system established in 1997, revised in Threshold for good chemical status is between class II/III.

Classification Water samples: – Concentration of all substances in all samples in the water body must be below the maximum limit (future EQS-MAC), and – Annual average concentration (arithmetic mean) must be below the mean limit for all substances (future EQS-AA).

Classification Sediment and biota: – The highest value measured within all monitoring stations in the WB must be below threshold value. – If high values are geographically concentrated to a specific part of the WB, one should consider delineation.

Classification - sediments Database Vann-nett Database Vannmiljø WB 1 WB 2 WB 3 WB St.1 St.2St.3St.4

Example of delineation based on sediment values: Note: These are Cu-levels, hence relevant for classification of ecological status. Principle of delineation is the same for pri-subst.

Monitoring of priority substances Based on knowledge of pressures, monitoring of a WB must include all priority substances that are being emitted. Monitoring should be performed in water, sediments and biota. MediumWaterSedimentsBiota Freq. (samples/year)1211

Detailed recommendations for monitoring in Norway are available at