4,4'-sulphonyldiphenol

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

0.025 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

0.55 mg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0.003 mg/L

Extrapolation method:

assessment factor

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

20 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

1.74 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

0.174 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:

0.332 mg/kg soil dw

Extrapolation method:

equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

no potential for bioaccumulation

Conclusion on classification

Acute data from fish and algae indicate L(E)C50 values for 4,4 -sulphonyldiphenol greater than 100 mg/L. The EC50 obtained for Daphnia is 55 mg/L, the NOEC obtained from a chronic toxicity study to aquatic invertebrates is 2.7 mg/L. The substance is not readily biodegradable and has no potential for bioaccumulation.
Considering the available data on the aquatic toxicity of 4,4 -sulphonyldiphenol as well as its fate properties, and taking into account the provisions laid down in REGULATION (EC) No 1272/2008 (CLP), there is no need to classify the substance for environmental hazards.

In the ZEOGRT study performed for 4,4 -sulphonyldiphenol, an unusually wide spacing factor has been chosen in agreement with the competent authorities. This was necessary to investigate potential endocrine effect of the test substance in the widest possible concentration range. In this respect, the approach taken was also useful and successful: the study clearly demonstrates that 4,4 -sulphonyldiphenol has no hormone-mediated effects on fish.
Furthermore, it has to be noted that a very minor effect (a significant, but slight decrease in body length in male animals of the F1 generation) has led to the determination of the LOEC at a concentration of 1.25 mg/L. Per definition, the next lower concentration is the NOEC, which is 0.25 mg/L in the current study. In fact, however, the study actually does not allow for the assessment of any possible effect in the concentration range between 0.25-1.25 mg/L. From the wide concentration spacing (chosen for the above reasons), a wide range of uncertainty arises here, which particularly covers the classification threshold of 1 mg/L. Due to the very mild effect observed at 1.25 mg/L, it can be reasonably assumed that the actual no effect concentration is close to this tested concentration, and possibly above 1 mg/L. Accordingly, from the perspective of the registrants, the NOEC obtained from the ZEOGRT study is not directly suitable for deriving the chronic classification of the registration item. For this reason, the Registrants are currently discussing the option of submitting a Testing proposal to precisely determine the chronic aquatic NOEC for 4,4 -sulphonyldiphenol by conducting an additional study using a targeted test design including, in particular, a narrow spacing around the classification threshold of 1 mg/L.