Résumé
The European Food Safety Authority has been asked to provide scientific opinions on the safety of smoke flavouring Primary Products used or intended for use in or on foods. This Opinion concerns one such Smoke Flavouring Primary Product, named Zesti Smoke Code 10.
The Primary Product Zesti Smoke Code 10 is obtained from a specified mixture of the following woods: hickory (Carya ovata) and oak (Quercus alba). The production of Zesti Smoke Code 10 comprises the following steps: (i) drying and sieving of the hardwood sawdust, (ii) heating of the dried sawdust in a specified reactor, (iii) condensing of the released smoke and (iv) separation of the aqueous part of the smoke condensate from precipitated tar. Essential parameters of the manufacturing process have been provided by the applicant.
Identification and quantification of Primary Product constituents have been performed using different batches than were used for the toxicological studies. In both cases several batches covering a production period from 2004 to 2005 were used. Considering a relative standard deviation for the batch-to-batch reproducibility of 5 to 35% for the content of the individual identified constituents the material used in testing can be considered as representative for the Primary Product Zesti Smoke Code 10 in general.
The water content of the Primary Product is 64 wt. %. The volatile fraction identified by capillary gas chromatographic analysis (GC) accounts for 15 wt. %. The total amount of the unidentified constituents account for 33 wt. %. The concentrations of the polycyclic aromatic hydrocarbons (PAHs) listed in the EFSA guidance document on submission of a dossier on a Smoke Flavouring Primary Product have been provided. The concentrations of the individual substances were only above 1 mu g/kg for benzo[j]fluoranthene (1.5 mu g/kg in batch 0115738 in 2007) and cyclopenta[c, d]pyrene (1.3 g/kg in batch 0103638 and 1.5 mu g/kg in batch 0320638 in 2006). The levels of benzo[ a] anthracene and benzo[a] pyrene were below the limits as laid down in Regulation (EC) No 2065/2003. Analysis of ten batches revealed no significant batch-to-batch variability. No data were provided on the stability of the Primary Product.
Normal use levels of the Primary Product proposed by the applicant range between 1 g/kg food (ready-to-eat savouries, soups and broths) and 2.5 g/kg food (meat and meat products). Dietary exposure for the Primary Product, as estimated by the applicant, was 30 mg/kg body weight per day.
In order to estimate dietary exposure to the Primary Product Zesti Smoke Code 10, the CEF Panel used two different methodologies, developed by the Panel specifically for smoke flavourings. Dietary exposure estimates were calculated by assuming that the Primary Product Zesti Smoke Code 10 is present at the normal or upper use levels provided by the applicant for the 18 food categories as outlined in Commission Regulation (EC). Dietary exposures from all sources range from 22.0 to 28.3 mg/kg bw/day, when assuming that the Primary Product Zesti Smoke Code 10 is present at the upper use levels, and from 9.3 to 11.7 mg/kg bw/day, when normal use levels are considered.
When dietary exposure estimates are based on use in only traditionally smoked foods dietary exposures range from 8.3 to 14.0 mg/kg bw/day, when assuming that the Primary Product Zesti Smoke Code 10 is present at the upper use levels, and from 4.2 to 6.5 mg/kg bw/day, when normal use levels are considered.
Genotoxicity studies conducted on Primary Product Zesti Smoke Code 10 included three in vitro studies (a bacterial reverse mutation test, a mammalian cell gene mutation assay and a chromosome aberration test) and two in vivo studies (a rat liver unscheduled DNA synthesis assay and a mouse bone marrow micronucleus test). The results obtained in these assays showed positive genotoxic responses in the in vitro assays but negative results in vivo in two well conducted studies.
Overall it is concluded that Primary Product Zesti Smoke Code 10 is genotoxic in vitro, whereas two in vivo genotoxicity tests were negative and sufficient to eliminate the concerns over the in vitro genotoxicity.
The Primary Product was investigated in two 90-day studies. The first one dates back to 1962 when Good Laboratory Practise (GLP) was not yet developed, the second one has been conducted recently according to GLP and OECD guidelines. The no-observed-adverse-effect level (NOAEL) was derived from the recent study based on the increased relative kidney weights and reduced body weight gain at the two highest dose groups and amounted to 2.5 g/kg diet equivalent to a minimum dietary intake calculated by the applicant of 134 mg/kg bw/day in male rats and 178 mg/kg bw/day in female rats.
The NOAEL from this recent 90-day study appears to be similar to the NOAEL from the older 90-day study. Since for this older study the pathology report stated that "somewhat more distinct minor degenerative changes were observed in the liver and kidney" at 20 g/kg diet, and because slightly more marrow hyperplasia was also noted in this group, it was concluded that the lowest dose level of 2.5 g/kg diet was the NOAEL.
Based on these data it is concluded that when assuming that the Primary Product Zesti Smoke Code 10 is present at the normal or upper use levels provided by the applicant for the 18 food categories, the margins of safety as compared to the NOAEL of 134 mg/kg bw/day derived from the 90-day toxicity study in rats amount to 5 - 6 for the intake estimates based on the upper use levels and to 11 - 14 when normal use levels are considered.
When assuming the use of Primary Product Zesti Smoke Code 10 in traditionally smoked products only, the margins of safety would amount to 10 - 16 for the intake estimates based on the upper use levels and to 21 - 32 when normal use levels are considered.
Given i) the fact that these margins of safety are based on a 90-day toxicity study, ii) the absence of data on reproduction and developmental toxicity and iii) the absence of long term studies, it is concluded that the uses and use levels of Primary Product Zesti Smoke Code 10 would require a larger margin of safety. The Panel concludes that the margin of safety is insufficient and that the use of Primary Product Zesti Smoke Code 10 at the proposed uses and use levels is of safety concern.
To decide whether despite the low margins of safety the use of Primary Product Zesti Smoke Code 10 might be approved for traditionally smoked products, at use levels specified, to replace smoking, is outside the remit of the Panel.