Registration Dossier

Diss Factsheets

Administrative data

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:
PNEC aqua (freshwater)
PNEC value:
2.1 mg/L
Assessment factor:
10
Extrapolation method:
assessment factor

Marine water

Hazard assessment conclusion:
no data: aquatic toxicity unlikely

STP

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

Sediment (freshwater)

Hazard assessment conclusion:
PNEC sediment (freshwater)
PNEC value:
2 720 mg/kg sediment dw
Assessment factor:
1
Extrapolation method:
equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:
no hazard identified

Hazard for air

Air

Hazard assessment conclusion:
no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:
PNEC soil
PNEC value:
329 mg/kg soil dw
Assessment factor:
1
Extrapolation method:
equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:
no potential for bioaccumulation

Additional information

PNEC sediment:


The PNECsediment can be derived from the PNECaquatic using the equilibrium partitioning method (EPM).


A distribution/partition coefficient (KD) between the water and sediment compartment for strontium has been determined. This resulted in a typical KD, susp-water of 1,291.8 L/kg (logKD: 3.11). In a first step the units have to be converted from L/kg to m3/m3 using the formula below.


KD, susp-water(m3/m3) = 0.9 + [0.1 x (KD, susp-water(L/kg) x 2,500) / 1,000]


This results in a KD, susp-matter of 323.9 m3/m3. This value can be entered in the equation below to calculate the PNECsediment:


PNECsediment = (KD, susp-water/ RHOsusp) x PNECaquatic x 1,000


with the PNECaquatic expressed as mg/L, RHOsusp representing the bulk density of wet suspended matter (freshly deposited sediment) (1,150 kg/m3), and a KD, susp-water of 323.9 m3/m3, a PNECsediment that is expressed as mg/kg wet weight can be derived. This value can be converted to a dry weight-based PNEC, using a conversion factor of 4.6 (CONVsusp = RHOsusp/Fsolid-susp * RHOsolid) kg wet weight/ kg dry weight.


This results in a PNECsediment of 2,720 mg Sr/kg dry sediment


PNEC soil:


The PNECsoil can be derived from the PNECaquatic using the equilibrium partitioning method (EPM).


A distribution/partition coefficient (KD) between the water and soil compartment was derived for strontium of 157.03 L/kg (Log KD: 2.2). In a first step the units have to be converted from L/kg to m3/m3 using the formula below.


KD,soil (m3/m3) = 0.2 +[0.6 x (KD,soil (L/kg) x 2,500) / 1,000]


This results in a KD,soil of 235.75 m3/m3. This value can be entered in the equation below to calculate the PNECsoil


PNECsoil = (KD,soil/ RHOsoil) x PNECaquatic x 1,000


With the PNECaquatic expressed as mg/L, RHOsoil representing the bulk density of wet soil (1,700 kg/m3) and KD,soil is 157.03 m3/m3, a PNECsoil expressed as mg/kg wet weight is derived. This value can be converted to a dry weight-based PNEC, using a conversion factor of 1.13 kg wet weight/ kg dry weight.


 


This results in a PNECsoilof 329 mg Sr/kg dry soil

Conclusion on classification

Short-term toxicity EC/LC50 values of Sr available for 3 trophic levels are situated between >40.3 mg Sr/L and >125 mg Sr/L, corresponding to > 55.9 mg/L and 173.6 mg/L strontium hydroxide based on an average Sr content of 72%. In accordance with Regulation (EC) No 1272/2008, Table 4.1.0 (a), classification for acute aquatic hazard is not required for strontium hydroxide as all EC50/LC50 values are above the classification criteria of 1 mg/L.

Long-term toxicity data are available for three trophic levels and range from 21 mg Sr/L to ≥ 43.3 mg Sr/L, corresponding to 29.2 mg/L and 60.1 mg/L strontium hydroxide based on an average Sr content of 72%. In accordance with Regulation (EC) No 1272/2008, Table 4.1.0 (b) (i), classification for chronic aquatic hazard is not required for strontium hydroxide as all chronic EC10/NOEC values are above the classification criteria of 1 mg/L.