SEMICARBAZIDE IN BABY FOOD

Transcription

1 SEMICARBAZIDE IN BABY FOOD Report nr. ND03V003/03 Dr. ir. K. Bouma drs. J. de Vries VOEDSEL EN WAREN AUTORITEIT Keuringsdienst van Waren Regionale dienst Noord Postbus AL Groningen tel.nr fax internetsite November 2003 VWA/KvW Noord report nr. ND03V003/03

2 CONTENTS page SUMMARY and KEYWORDS SAMENVATTING en TREFWOORDEN 1. INTRODUCTION Semicarbazide in foodstuffs Toxicological properties of semicarbazide Legal aspects Research aim 1 2. EXPERIMENTAL Sampling Analysis of food Analysis of lids 2 3. RESULTS AND DISCUSSION Semicarbazide in baby food Semicarbazide in other foodstuffs Semicarbazide in lids 5 4. CONCLUSIONS 6 5. LITERATURE 6 VWA/KvW Noord report nr. ND03V003/03

3 SUMMARY and KEYWORDS In July 2003 the European Food Safety Authority (EFSA) was informed by industry about the presence of traces of semicarbazide in food (up to 20 µg/kg), packaged in glass jars sealed with a lid. These foodstuffs comprise baby food, fruit, vegetables, jams, honey and sauces. The probable origin of semicarbazide is the use of the authorised blowing agent azodicarbonamide in the foamed plastic layer, used as sealing ring in the lid. During processing or sterilisation azodicarbonamide may decompose into semicarbazide, which then migrates into the food In October 2003 the Inspectorate for Health Protection & Veterinary Public Health of the Food and Consumer Product Safety Authority performed a fast survey, to determine the level of semicarbazide in baby food and some other foodstuffs. As babies form a vulnerable group of consumers, baby food was selected to start with. 40 glass jars of baby food of 7 different brands were sampled, containing fruit, vegetables, meat, pasta, and combinations thereof. The level of semicarbazide varied from 3 to 26 µg/kg food, the average value being 13 µg/kg. 22 glass jars of fruit and vegetables were also sampled and analysed. The level of semicarbazide in these foods varied from not detectable up to 2 µg/kg. This is much lower than for baby food. An explanation of this finding is the more favourable ratio between food content and lid surface. Unused lids for baby food jars have been extracted and high levels of semicarbazide have been detected. This indicates that these lids are the most probable origin for semicarbazide in baby food. Based on these results, the RIVM (National Institute of Public Health and the Environment) carried out a risk assessment. It was concluded that these levels of semicarbazide in baby food form a very low, if not negligible, health risk for babies. KEYWORDS: semicarbazide, lid, glass jar, baby food, fruit, vegetables VWA/KvW Noord report nr. ND03V003/03

4 SAMENVATTING en TREFWOORDEN In juli 2003 werd de European Food Safety Authority (EFSA) door de industrie geïnformeerd over de aanwezigheid van sporen van semicarbazide (tot 20 µg/kg) in levensmiddelen, verpakt in glazen potten afgesloten met een deksel. Voorbeelden van deze levensmiddelen zijn babyvoeding, fruit, groente, jam, honing en sauzen. De waarschijnlijke bron van semicarbazide is het gebruik van het toegelaten blaasmiddel azodicarbonamide in het geschuimde plastic laagje, gebruikt als afdichtring in het deksel. Gedurende verwerking of sterilisatie zou azodicarbonamide kunnen degraderen in semicarbazide, dat vervolgens migreert naar het levensmiddel. In oktober 2003 heeft de VWA/Keuringsdienst van Waren een snel marktonderzoek uitgevoerd naar de gehaltes van semicarbazide in babyvoeding en andere levensmiddelen. Gestart is met babyvoeding omdat baby's een kwetsbare groep consumenten vormen. 40 glazen potjes babyvoeding zijn bemonsterd van 7 verschillende merken, welke fruit, groente, vlees, pasta en combinaties daarvan bevatten. Het gehalte aan semicarbazide varieerde van 3 tot 26 µg/kg, met een gemiddeld gehalte van 13 µg/kg. Verder werden ook 22 glazen potten met fruit en groentes bemonsterd en geanalyseerd. Het gehalte aan semicarbazide varieerde tussen niet aantoonbaar en 2 µg/kg. Dit is veel lager dan in babyvoeding. Een mogelijke verklaring is de meer gunstige verhouding tussen inhoud en deksel oppervlak. Ongebruikte deksels voor glazen potjes babyvoeding zijn geëxtraheerd. Hoge gehaltes aan semicarbazide werden aangetoond. Dit duidt er op dat deze deksels de meest waarschijnlijke bron zijn voor semicarbazide in babyvoeding. Op basis van deze resultaten heeft het RIVM een risico analyse uitgevoerd. Het RIVM concludeerde dat deze gehaltes van semicarbazide in babyvoeding een laag, zo niet verwaarloosbaar, gezondheidsrisico vormden voor baby's. TREFWOORDEN: semicarbazide, deksel, glazen pot, babyvoeding, fruit, groente VWA/KvW Noord report nr. ND03V003/03

5 1. INTRODUCTION 1.1 Semicarbazide in foodstuffs In July 2003 the European Food Safety Authority (EFSA) was informed by industry that semicarbazide has been found in a number of food products from different manufacturers that are packaged in glass jars with metal lids sealed with PVC gaskets [5.1]. These foodstuffs comprise types of baby foods, fruit juices, jams, honey, sterilised vegetables and sauces. The probable origin of semicarbazide is, according to industry, the blowing agent azodicarbonamide, used to make a foamed plastic layer, which is suitable for gaskets. This link has, however, not been clearly established. The amounts of semicarbazide that have been detected in foods are very low, ranging from not detectable up to 20 µg/kg (0.02 mg/kg). In Figure 1 the structures of both azodicarbonamide and semicarbazide are shown. N H 2 O N N NH 2 O O H 2 N NH NH 2 Figure 1: Structure of azodicarbonamide (CAS nr ) and semicarbazide (CAS nr ) Foodstuffs, packaged in glass jars, are normally sterilised in these jars. During this heat treatment, thermal degradation of azodicarbonamide into semicarbazide may occur. Sterilisation can be done by leading the sealed glass jars through a hot bath. This process can be speeded up by rotating the glass jars during this heat treatment. In this case, the contact between the foodstuff and the lid is intensified. 1.2 Toxicological properties of semicarbazide Limited toxicological data are available for semicarbazide. It belongs, however, to a family of chemicals (hydrazines) which are known to cause cancer in animals. Semicarbazide is weakly genotoxic in some in vitro tests [5.2]. The limited in vivo experimental data available are insufficient to assess whether the activity observed in vitro is also expressed in vivo. Semicarbazide appears to be only a weak carcinogen [5.2]. 1.3 Legal aspects Plastic food contact materials are regulated on EU level (Directive 2002/72/EC [5.3]). This Directive has been implemented in Chapter I (Plastics) of the Dutch Packaging and Food-Utensils Regulation (Food and Commodities Act) [5.4]. Azodicarbonamide (PM/REF nr ) is authorised as an additive for plastic food contact materials, with the restriction that it is only permitted as blowing agent. Decomposition products of authorised substances may be present in the end product, on the condition that these decomposition products do not migrate into the foodstuff in quantities that could endanger human health or bring about an unacceptable change in organoleptic properties. Several carcinogenic substances have been authorised as starting substances for food contact materials, with the restriction that these substances may not be detectable in the foodstuff. Examples are vinylchloride and acrylamide. For practical reasons, for these substances a detection limit has been established of 0.01 mg/kg, excluding analytical tolerance. At this level the analytical tolerance is set at 100%. Therefore measures are taken when the level of these substances exceeds 0.02 mg/kg. Analogously, in the worst case assuming that semicarbazide is a genotoxic carcinogenic substance, the migration should not exceed 0.02 mg/kg foodstuff. 1.4 Research aim To determine whether the level of semicarbazide in food could form a (potential) health problem, the Dutch Food and Consumer Product Safety Authority carried out a survey. Baby food has been selected, as this concerns a vulnerable consumer group. Glass jars of baby food of the different brands, present on the Dutch market, have been sampled and analysed for content of semicarbazide. For comparison, several glass jars of fruit and vegetables have been analysed also. In addition, unused lids have been analysed as well for the content of semicarbazide, in order to establish whether these lids may be the origin of semicarbazide in the food. VWA/KvW Noord report nr. ND03V003/03 1

6 2. EXPERIMENTAL 2.1 Sampling Sampling of glass jars of baby foods took place in the regions East and North of the Netherlands. In October glass jars have been sampled, containing pasta, fruits, vegetables, meats and combinations thereof, and varying in size and food content. Baby foods of most of the brands present on the Dutch market have been sampled. Also 22 glass jars containing fruit and vegetables have been sampled. Furthermore, in the region East, unused lids for glass jars for baby foods have been sampled. 2.2 Analysis of baby foods Samples were analysed for semicarbazide (SEM) by a procedure that was developed by RIKILT institute, Wageningen, the Netherlands. Food samples were hydrolysed in a hydrochloric acid solution overnight while SEM was derivatised with 2- nitrobenzaldehyde. The solution was brought to ph 7 and the reaction product was extracted with ethyl acetate. The solvent was evaporated; the extract was dissolved in water and injected after filtration. A calibration line was set up in a blank food matrix. The isotope-labelled SEM-1,2-15 N2,5-13 C, chemically identical to the analyte, served as the internal standard. The method was validated in the matrix of baby food. The detection limit of semicarbazide is 0.3 µg/kg, the limit of quantification is 0.6 µg/kg. 2.3 Analysis of lids For the lids of the jars, the analytical procedure is similar to the analysis of food samples. The calibration line was constructed in blank hydrochloric acid solution. It proved to be essential to remove the rubber lids from their metal encasing prior to the analysis. Metals that are extracted in hydrochloric acid during the hydrolysis step seriously disturb the subsequent analysis. Since the method only served to give an initial estimation of the concentration, it was not validated. However, because the internal standard is chemically identical to the analyte, no serious problems can be expected here. The specificity of the method was checked by subjecting ADA, the precursor of SEM, to the analytical procedure. No crossreaction of ADA was observed. VWA/KvW Noord report nr. ND03V003/03 2

7 3. RESULTS AND DISCUSSION 3.1 Semicarbazide in baby food In Table 1 an overview is presented of the results of baby foods, ordered by brand. Semicarbazide has been detected in all baby foods, varying from 3 to 26 µg/kg, the average SEM concentration being 13 µg/kg. Similar values were found by the industry. In Figure 2 the analysed concentration of semicarbazide is plotted versus the content for the different brands. This results in a scatter of results. There appears to be no relation between the level of semicarbazide, type of foodstuff, the content, or the brand. Table 1: Semicarbazide content of different types of baby foods sample nr. food content of food(g) semicarbazide (µg/kg) hodgepodge with cheese potato and turkey apple and strawberry spaghetti bolognese apple and banana vegetables and ham pear and mandarin apple, banana and potato spinach and beef tomato, chicken and rice carrots and chicken apple, banana and corn potato and veal vegetables beans carrots vegetables, chicken and rice veal and vegetables tomato and chicken potato, vegetables and fruit rice, vegetables and chicken potato and carrots rice, vegetables and chicken vegetables vegetables, rice and turkey potato, vegetables and fruit macaroni and ham fruit pilav with vegetables spinach and chicken bolognese carrots broccoli pear and apple pear mixed vegetables pear, apple and oat spinach and potato carrot and apple fruit cocktail VWA/KvW Noord report nr. ND03V003/03 3

8 semicarbazide (ug/kg) brand 1 brand 2 brand 3 brand 4 brand 5 brand 6 brand content (g) Figure 2: Level of semicarbazide plotted versus food content for the different brands of baby food The RIVM (National Institute of Public Health and the Environment) carried out a risk assessment, based on our results of semicarbazide in baby food [5.5]. The exposure of babies to semicarbazide due to the intake of these baby foods is estimated to be 2.5 µg/kg body weight/day, during month 6 to 12 in their first year. The RIVM has set the limit for an acceptable cancer risk, based on the intake of semicarbazide, at 30 µg/kg body weight/day. Therefore it was concluded that the carcinogenic risk of semicarbazide in baby foods is very small, if not negligible. 3.2 Semicarbazide in other foodstuffs In Table 2 the results are shown of the level of semicarbazide in 22 samples of fruit and vegetables. The highest level was 2 µg/kg, much lower than for baby foods. An explanation may be that the ratio between surface of lid and volume of jar is more favourable for larger jars. Table 2: Semicarbazide content of fruit and vegetables packaged in glass jars sample nr. food semicarbazide (µg/kg) apple compote n.d white beans mushrooms green peas apple compote n.d cocktail unions n.d French beans cherries in syrup apple compote green peas n.d applesauce red beets cream spinach white beans n.d applesauce applesauce n.d French beans n.d red cabbage and apple n.d white beans in tomato sauce n.d spinach n.d apple compote n.d French beans 0.5 n.d. not detectable: detection limit is 0.03 µg/kg VWA/KvW Noord report nr. ND03V003/03 4

9 3.3 Semicarbazide content in lids Unused lids have been analysed, to determine whether these lids are the origin of the semicarbazide. High levels were found, up to 14 mg/kg. This was outside of the range of calibration, therefore this value is only an indication. Industry indicated that levels of 1-7 mg/kg have been found in these lids, this is in the same order as found by our laboratory. These high levels of semicarbazide in unused lids, however, indicate that they are very likely the (main) origin of semicarbazide in baby food. VWA/KvW Noord report nr. ND03V003/03 5

10 4. CONCLUSIONS Semicarbazide was present in baby food in levels varying from 3 to 26 µg/kg, the average value being 13 µg/kg. There is no relation between the level of semicarbazide and the type of food or brand. In larger glass jars for fruit and vegetables, semicarbazide was also found. The levels were lower than for baby food, varying from not detectable to 2 µg/kg. In unused lids for baby food high levels of semicarbazide have been detected. This indicates that these lids are the most probably origin of the semicarbazide found in baby food. At these low levels of contamination with SEM, the health risk for babies is expected to be very small if not negligible. 5. LITERATURE 5.1. Advice of the ad hoc expert group set up to advise the European Food Safety Authority (EFSA) on the possible occurrence of semicarbazide in packaged foods. Brussels, 28 July AFC/adhoc SEM/ Statement of the Scientific Panel on Food Additives, Flavourings, Processing Aids en Materials in Contact with Food updating the advice available on semicarbazide in packaged foods. Brussels, 1 October EFSA/AFC/FCM/17- final. 5.3 Commission Directive 2002/72/EC of 6 August 2002 relating to plastic materials and articles intended to come into contact with foodstuffs. Official Journal L 220, 15/08/2002 P Packaging and Food-Utensils Regulation (Food and Commodities Act) of 20 November 1979, Stcrt.1980, RIVM/Centrum voor Stoffen en Integrale Risicoschatting (SIR). Advies naar aanleiding van het voorkomen van Semicarbazide in babyvoeding. 15 oktober VWA/KvW Noord report nr. ND03V003/03 6