Registration Dossier

Administrative data

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:
PNEC aqua (freshwater)
PNEC value:
0.002 mg/L
Assessment factor:
10
Extrapolation method:
assessment factor
PNEC freshwater (intermittent releases):
0.001 mg/L

Marine water

Hazard assessment conclusion:
PNEC aqua (marine water)
PNEC value:
0 mg/L
Assessment factor:
100
Extrapolation method:
assessment factor

STP

Hazard assessment conclusion:
PNEC STP
PNEC value:
100 mg/L
Assessment factor:
100
Extrapolation method:
assessment factor

Sediment (freshwater)

Hazard assessment conclusion:
PNEC sediment (freshwater)
PNEC value:
0.08 mg/kg sediment dw
Extrapolation method:
equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:
PNEC sediment (marine water)
PNEC value:
0.008 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:
0.796 mg/kg soil dw
Assessment factor:
10
Extrapolation method:
assessment factor

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:
no potential for bioaccumulation

Additional information

N-tert-butylbenzothiazole-2-sulphenamide has been self-classified before. However, based on up-to-date ecotoxicological studies, new classification for aquatic environment is recommended.

Conclusion on classification

The classification of TBBS is not yet contained in Annex I of Directive 67/548/EEC nor in the regulation (EC) No 1272/2008, but a self classification as R50/53 and aquatic acute 1 (H400) and aquatic chronic 1 (H410) is available.

The up-to-date information confirmed this classification and is summarised below:

- The most sensitive acute and chronic toxicity is to aquatic algae (Scenedesmus capricornutum): 72h- ECr50 of 0.071 mg/L and NOEC of 0.023 mg/L( Ministry of the Environment, Japan, 1996).

- Measured log Pow of 3.36 (DUSLO, 2007), which is higher than 3.

- TBBS is not readily biodegradable (Bayer AG, 1991).

With the data listed above, TBBS should be classified as R50/53 and aquatic acute 1 (H400) and aquatic chronic 1 (H410). The appropriate multiplying factors for acute and chronic toxicity are10 and 1 respectively.