Registration Dossier

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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
basic toxicokinetics in vivo
Data waiving:
study scientifically not necessary / other information available
Justification for data waiving:
other:
Justification for type of information:
From the available data combined with the knowledge of the fate of proteins in the gastrointestinal system, it can be concluded that absorption of proteins in toxicological significant amounts through the gastrointestinal tract is unlikely. Proteins, in general, are a natural and necessary part of human and animal diets, and are subjected to rapid degradation by digestive enzymes in the gastrointestinal tract into individual amino acids and small peptides that can be absorbed by the body to support nutritional needs. Large proteins are not known to be absorbed by the intestinal epithelium.
Dermal absorption is not expected.

Since proteins have a large size and are hydrophilic in nature, they cannot permeate passively across the skin due to the stratum corneum which allows the transport of only small lipophilic molecules. The spider silk protein has a molecular weight of 142.8 kDa and therefore dermal absorption can be excluded.

For MW ≥ 40 kDa there is a low likelihood that an inhaled protein would cross into the systemic circulation to potentially cause pharmacological (see attached justification).

Description of key information

From the available data combined with the knowledge of the fate of proteins in the gastrointestinal system, it can be concluded that absorption of proteins in toxicological significant amounts through the gastrointestinal tract is unlikely. Proteins, in general, are a natural and necessary part of human and animal diets, and are subjected to rapid degradation by digestive enzymes in the gastrointestinal tract into individual amino acids and small peptides that can be absorbed by the body to support nutritional needs. Large proteins are not known to be absorbed by the intestinal epithelium.
Dermal absorption is not expected.


Since proteins have a large size and are hydrophilic in nature, they cannot permeate passively across the skin due to the stratum corneum which allows the transport of only small lipophilic molecules. The spider silk protein has a molecular weight of 142.8 kDa and therefore dermal absorption can be excluded.


For MW ≥ 40 kDa there is a low likelihood that an inhaled protein would cross into the systemic circulation to potentially cause pharmacological effects.


 

Key value for chemical safety assessment

Bioaccumulation potential:
no bioaccumulation potential

Additional information