Catalase

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

26.2 µg/L

Assessment factor:

1 000

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

262 µg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

2.62 µg/L

Assessment factor:

10 000

Extrapolation method:

assessment factor

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

65 000 µg/L

Assessment factor:

1

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

no exposure of sediment expected

Sediment (marine water)

Hazard assessment conclusion:

no exposure of sediment expected

Hazard for air

Air

Hazard assessment conclusion:

no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:

PNEC soil

PNEC value:

3.48 µg/kg soil dw

Extrapolation method:

equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

no potential for bioaccumulation

Additional information

Catalase belongs to the sub-subclass of peroxidases and since no toxic effects were observed in the supporting study with catalase, it can be assumed that catalase has the same ecotoxicity profile as peroxidase and thus read-acros to peroxidases is considered applicable.

The aquatic toxicity data for peroxidase were obtained from short term toxicity studies in species representing two trophic levels (i.e. algae and crustacean).

Peroxidase was tested on aquatic invertebrate Daphnia magna and algae Scenedesmus suhspicatus. Analysis of the immobility of Daphnia magna exposed to peroxidase in concentrations up to 560 mg/L (155 mg/L active enzyme protein) for 48 hours revealed an EC50 value of 95 mg/L, equivalent to 26.2 mg/L active enzyme protein.

Exposure of Scenedesmus suhspicatus to peroxidase for 72 hours in concentrations up to 1000 mg/L (276 mg/L active enzyme protein) produced the following EC50 values:

EbC50 (72 h): 320 mg/L (95 % confidence limits 290 - 360 mg/L); 88.3 mg/L active enzyme protein

ErC50 (24 - 72 h): 640 mg/L (95 % confidence limits 560 - 730 mg/L); 176.6 mg/L active enzyme protein

The crustacean EC50 value of 26.2 mg active enzyme protein/L was used for PNEC derivation and the assessment factors 1000 and 10000 were applied for fresh and marine water, respectively.

The PNEC value for STP is based on actual measurements of enzyme concentration in STP connected to manufacturing site. Up to 65000 µg active enzyme protein were detected in STP connected to manufacturing site and since there was no negative impact observed, this concentration is the estimated PNEC value for STP.

PNEC values for sediment exposure have not been derived because peroxidase is readily biodegradable, highly water soluble and has a very low potential for adsorption to sediments. Exposure of the sediment to toxicologically significant concentrations of the test substance is thus not expected.

As no soil ecotoxicity data are available for peroxidase, the PNEC for soil is based on the PNEC for surface water using the equilibrium partitioning method. PNEC soil was estimated to 3.08 µg/kg soil ww. Assuming a water fraction of 20% w/w, PNEC for soil dry weight (dw) has been estimated to be 3.48 μg aep/kg soil dw.

Peroxidase is not expected to cause any significant secondary poisoning as it is ready biodegradable and has no bioaccumulation potential. Furthermore, as peroxidase is a protein it is expected to be degraded in the gastrointestinal tract. Thus PNEC oral is not relevant.

Conclusion on classification

Based on the aquatic toxicity studies and the ready biodegradation of the enzyme, catalase is not classified.