Oxidase, monoamine

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING
The results of aquatic toxicity tests that have been conducted on enzyme preparations by others demonstrate that they are not appreciably toxic to aquatic organisms including daphnids. For example, HERA [1] conducted a risk assessment on three very different classes of enzymes (enzyme preparations of alpha amylase, cellulase and lipase) commonly found in household products. EC50 values for daphnids ranged from 450 to greater than 1,000 mg/L.

In 2002, an extensive review on enzymes was published entitled Collection of Information on Enzymes [2]. The review was supported by the Directorate General Environment of the European Commission and conducted by the Austrian Federal Environment Agency. Based on the studies reviewed, the report concluded that “enzymes seem unlikely to be dangerous to the aquatic environment due to their ready biodegradability and the low effects on aquatic life”. Although the database and number of enzymes reviewed were limited, the pattern of toxicity was clear and the authors were able to reach the above conclusion based on the studies reviewed. The widespread use of enzymes has been followed by investigations relevant for ecotoxicity. Investigations are mainly performed to establish knowledge on short-term aquatic toxicity and on the rate of biodegradability of the enzyme. Non-proteolytic enzymes, such as monoamine oxidase, should not be classified as harmful or toxic to the environment [3].

There are several mitigating factors which indicate that both aquatic toxicity due to the presence of enzymes is unlikely to occur and that any observed toxicity could be the result of physical effects due to the complex composition of enzyme preparations which are classified at UVCB substances (Unknown or Variable Composition).

The use of aquatic toxicity studies with daphnids in general are problematic for testing with large complex macromolecules like enzymes. This is particularly true for the testing of enzyme preparations which are mixtures and not pure substances. Daphnids are very sensitive to osmotic stress and other physical factors in their environment quite unrelated to any toxicological properties of the substance in question. Previous use of daphnids for testing complex mixtures such as leachates have resulted in the need to modify the testing protocol to buffer for pH and other physical factors in the test material media. Round robin studies had to be performed to adapt the test protocol and still the results have been the subject of interpretation and misinterpretation. The acute toxicity with daphnids is not a good test model for enzyme preparations.
[1] HERA Human and environmental risk assessment on ingredients of household cleaning products - alpha-amylases, cellulases and lipases. 2005.
[2] Aberer W, Hahn M, Klade M, Seebacher U, Spök A, Wallner K, Witzani H (2002): Collection of information on enzymes. Final report. European Communities, ISBN 92-894-4218-2
[3] Enzymes REACH Consortium (2010). Data waiving argumentation for technical enzymes.

Description of key information

The results of aquatic toxicity tests that have been conducted on enzyme preparations by others demonstrate that they are not appreciably toxic to aquatic organisms including daphnids.  For example, HERA [1] conducted a risk assessment on three very different classes of enzymes (enzyme preparations of alpha amylase, cellulase and lipase) commonly found in household products.  EC50 values for daphnids ranged from 450 to greater than 1,000 mg/L.

 

In 2002, an extensive review on enzymes was published entitled Collection of Information on Enzymes [2].  The review was supported by the Directorate General Environment of the European Commission and conducted by the Austrian Federal Environment Agency.  Based on the studies reviewed, the report concluded that “enzymes seem unlikely to be dangerous to the aquatic environment due to their ready biodegradability and the low effects on aquatic life”. Although the database and number of enzymes reviewed were limited, the pattern of toxicity was clear and the authors were able to reach the above conclusion based on the studies reviewed. The widespread use of enzymes has been followed by investigations relevant for ecotoxicity. Investigations are mainly performed to establish knowledge on short-term aquatic toxicity and on the rate of biodegradability of the enzyme. Non-proteolytic enzymes, such as monoamine oxidase, should not be classified as harmful or toxic to the environment [3].

 

There are several mitigating factors which indicate that both aquatic toxicity due to the presence of enzymes is unlikely to occur and that any observed toxicity could be the result of physical effects due to the complex composition of enzyme preparations which are classified at UVCB substances (Unknown or Variable Composition).

 

The use of aquatic toxicity studies with daphnids in general are problematic for testing with large complex macromolecules like enzymes.  This is particularly true for the testing of enzyme preparations which are mixtures and not pure substances.  Daphnids are very sensitive to osmotic stress and other physical factors in their environment quite unrelated to any toxicological properties of the substance in question.  Previous use of daphnids for testing complex mixtures such as leachates have resulted in the need to modify the testing protocol to buffer for pH and other physical factors in the test material media.  Round robin studies had to be performed to adapt the test protocol and still the results have been the subject of interpretation and misinterpretation.  The acute toxicity with daphnids is not a good test model for enzyme preparations.

 

The most sensitive EC50 daphnid toxicity value of 450 mg aep/L for amylases was used for the PNEC derivations.

 

[1] HERA Human and environmental risk assessment on ingredients of household cleaning products - alpha-amylases, cellulases and lipases. 2005.

[2] Aberer W, Hahn M, Klade M, Seebacher U, Spök A, Wallner K, Witzani H (2002): Collection of information on enzymes. Final report. European Communities, ISBN 92-894-4218-2

[3] Enzymes REACH Consortium (2010). Data waiving argumentation for technical enzymes.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Remarks:

mg active enzyme protein / L

Effect concentration:

450 mg/L