Registration Dossier

Administrative data

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:
PNEC aqua (freshwater)
PNEC value:
0.62 µg/L
Assessment factor:
3
Extrapolation method:
sensitivity distribution

Marine water

Hazard assessment conclusion:
PNEC aqua (marine water)
PNEC value:
2.36 µg/L
Assessment factor:
3
Extrapolation method:
sensitivity distribution

STP

Hazard assessment conclusion:
PNEC STP
PNEC value:
0.37 mg/L
Assessment factor:
10
Extrapolation method:
assessment factor

Sediment (freshwater)

Hazard assessment conclusion:
PNEC sediment (freshwater)
PNEC value:
53.8 mg/kg sediment dw
Assessment factor:
10
Extrapolation method:
assessment factor

Sediment (marine water)

Hazard assessment conclusion:
PNEC sediment (marine water)
PNEC value:
69.8 mg/kg sediment dw
Assessment factor:
10
Extrapolation method:
assessment factor

Hazard for air

Air

Hazard assessment conclusion:
no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:
PNEC soil
PNEC value:
10.9 mg/kg soil dw
Assessment factor:
2
Extrapolation method:
sensitivity distribution

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:
no potential for bioaccumulation

Additional information

Conclusion on classification

The EU CLP guidance document (ECHA 2017) permits consideration of the “environmental transformation” of metals in the environment, including removal from the water column and deposition and sequestration in sediments, much the same way as the concept of “rapid degradation” is considered for organic chemicals. To indicate “rapid removal” for a metal, it is assumed that one must demonstrate greater than 70% removal of soluble metal within 28 days of addition to the water column, as is the case with organic compounds. Furthermore, one must demonstrate that the potential for metal remobilisation from sediments is limited, for example by changes in metal speciation, remineralisation and permanent burial in the sediment. If these conditions are met, the metal is considered “rapidly removable” and poses lower chronic environmental risk. Results of modelling using the Unit World Model (UWM) and initial empirical testing via the extended transformation/dissolution protocol (e-TDp) indicate that the cobalt ion satisfies the requirements for “rapid” metals removal, i.e. > 70% removal from the water column in 28 days, and the limited sediment remobilisation potential under most environmental conditions.

The lowest available acute reference value is:

Algae, Pseudokirchneriella subcapitata (following OECD Method 201)
           EC50: 0.654 mg/L (0.109 mg Co/L)

No compound specific acute data are available for invertebrates or fish species

Data classify substance as Acute 1; M = 1

 

Available chronic EC10values for algae and invertebrates are:

Algae, Pseudokirchneriella subcapitata (following OECD Method 201)
           EC10: 0.219 mg/L (0.036 mg Co/L)

Invertebrate, Ceriodaphnia dubia
           EC10: 0.119 mg/L (0.0197 mg Co/L)

No compound specific chronic data are available for fish species,but fish generally least sensitive

Chronic data classify substance as Chronic 2 or 3 depending on rapid removal

Chronic tests take precedence over acute data for chronic classification, so acute algae value not considered under surrogate scheme

 

There is no evidence for bioaccumulation or biomagnification in the environment

 

Proposed self-classification:

Acute 1 (M = 1) and Chronic 3