1,1'-(1,1,2,2-tetramethylethylene)dibenzene

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

0.08 mg/L

Assessment factor:

1

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

0.08 mg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0.08 mg/L

Assessment factor:

1

Extrapolation method:

assessment factor

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

10 mg/L

Assessment factor:

100

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

249.6 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

249.6 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Hazard for air

Air

Hazard assessment conclusion:

no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:

PNEC soil

PNEC value:

49.7 mg/kg soil dw

Extrapolation method:

equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

no potential to cause toxic effects if accumulated (in higher organisms) via the food chain

Additional information

PNECs considering the reference substance were deduced from the water solubility for each compartment/endpoint as it represents a worst-case scenario.

The PNEC derivation was as follows justified:

PNEC freshwater sediment:

K_(susp-water) = 780

RHO_(susp) = 1150

Conversion factor (wwt -> dwt): 4.6

PNEC_freshwater sediment

= (K_(susp-water) / RHO_(susp)) * PNEC_water * 1000

= (780/1150) * 0.08 * 1000

= 54.3 mg/kg wwt

= 249.6 mg/kg dw

 

PNEC marine water sediment:

K_(susp-water) = 780

RHO_(susp) = 1150

Conversion factor (wwt -> dwt): 4.6

PNEC_marine water sediment

= (K_(susp-water) / RHO_(susp)) * PNEC_marine water * 1000

= (780/1150) * 0.08 * 1000

= 54.3 mg/kg wwt

= 249.6 mg/kg dw

 

PNEC soil:

K_(soil-water) = 935

RHO_(soil) = 1700

Conversion factor (wwt -> dwt): 1.13

PNEC_soil

= (K_(soil-water) / RHO_(soil)) * PNEC_freshwater * 1000

= (935/1700) * 0.08 * 1000

= 44 mg/kg wwt

= 49.7 mg/kg dw

Conclusion on classification

Aquatic acute toxicity

96 h, LC50 (Danio rerio): >1000 mg/L (nominal concentration based on loading rate)

48 h, EC50 (Daphnia magna): >1000 mg/L (nominal concentration based on loading rate)

72 h, ErC50 (Pseudokirchneriella subcapitata): >1000 mg/L (nominal concentration based on loading rate)

 

Aquatic chronic toxicity

72 h, ErC10 (Pseudokirchneriella subcapitata): >100 - <1000 mg/L (nominal concentration based on loading rate)

 Biodegradation: not biodegradable: 0.2 % after 28 days (% degradation O2 consumption, OECD 301 D)

Partition coefficient: log Kow = 6.68 at 20 °C

 

Classification according to CLP

The available experimental test data are reliable and suitable for classification purposes under Regulation (EC) No 1272/2008. The test substance was found to not be readily biodegradable under the test conditions. Due to the low water solubility of the reference substance supersaturated solutions were prepared, thereby simulating worst-case scenario conditions in all relevant ecotoxicological studies. In the three short-term ecotoxicological studies (96-h Fish, 48-h Daphnia, 72-h Algae) the EC50 values are all above 1000 mg/L (loading rate, WAF). Based on these results, the substance is neither classified as short-term (acute) aquatic toxicity nor classified as long-term (chronic) aquatic toxicity according to Regulation (EC) No 1272/2008 (CLP), as amended for the eighteenth time in Regulation (EU) 2022/692.