AQUASTA is a feed additive used in fish feed (farmed salmon and trout) to color flesh. It contains approximately 99.5% of dried, inactivated and enzyme treated Phaffia rhodozyma yeast (strain ATCC SD-5340) containing nominally 1% w/w astaxanthin. The product is formulated with 0.5% ascorbic acid added as an antioxidant. The European Food Safety Authority has been requested to assess the efficacy and safety of this product for the target animals, the users, the consumers and the environment.
The FEEDAP Panel recently concluded on the safety of astaxanthin. The present evaluation of AQUASTA is therefore limited to the efficacy of the yeast as astaxanthin source and the safety of the yeast itself.
The studies presented in the dossier were performed with ASTAXIN, which is described by the applicant to be identical to AQUASTA except for the antioxidant used in the product (ethoxyquin instead of ascorbic acid). All the following conclusions of the FEEDAP Panel are based on this statement.
The colorizing potential of ASTAXIN has been satisfactorily demonstrated in three trials on the most economically important salmonid species at dietary astaxanthin contents of 28 to 44 mg kg-1 feed in rainbow trout and 26 to 52 mg kg-1 in Atlantic salmon.
AQUASTA is considered safe for salmonid species at the proposed inclusion levels. The Phaffia product tested was tolerated by Atlantic salmon for 12 months at eightfold concentration of the highest level approved in feed. ASTAXIN exerts negligible or no antibacterial activity against common environmental and fish gut flora bacterial species and pathogens.
The FEEDAP Panel considers the use of astaxanthin as a feed additive in salmonid feed at the maximum level approved, safe for the consumer.
Data on ASTAXIN shows no evidence of mutagenicity or toxicological effects of concern either following an acute dose or after 90 days. The FEEDAP Panel sees no evidence for adverse effects but cannot finally conclude on the consumer safety for AQUASTA due to the inadequacies of the 90 days study.
The finding of dermal sensitization with ASTAXIN is considered likely to be also relevant to AQUASTA and no conclusion on inhalation toxicity could be drawn due to exposure by that route. Due to the characteristics of the product, labelling as a respiratory sensitizer should be considered appropriate. The lack of irritancy of ASTAXIN cannot be assumed to also apply to AQUASTA without direct evidence.
AQUASTA consists of 99.5 % of dried inactivated Phaffia rhodozyma yeast. The yeast is not expected to be of consequence to environment. In its opinion on astaxanthin the FEEDAP Panel did not expect that the use of astaxanthin as feed additive for salmon and trout would pose a significant risk to the environment.
Related article:
New natural astaxanthin in production
