Assessment of the impact of the IARC Monograph Vol. 121 on the safety of the substance styrene (FCM No 193) for its use in plastic food contact materials
2020; Wiley; Volume: 18; Issue: 10 Linguagem: Inglês
10.2903/j.efsa.2020.6247
ISSN1831-4732
AutoresVittorio Silano, José Manuel Barat Baviera, Claudia Bolognesi, Andrew Chesson, Pier Sandro Cocconcelli, Riccardo Crebelli, David Michael Gott, Konrad Grob, Claude Lambré, Evgenia Lampi, Marcel Mengelers, Alicja Mortensen, Inger‐Lise Steffensen, Christina Tlustos, Henk Van Loveren, Laurence Vernis, Holger Zorn, Laurence Castle, Emma Di Consiglio, Roland Franz, Nicole Hellwig, Maria Rosaria Milana, Karla Pfaff, Maria Carfì, Ellen Van Haver, Gilles Rivière,
Tópico(s)Carcinogens and Genotoxicity Assessment
ResumoEFSA JournalVolume 18, Issue 10 e06247 Scientific OpinionOpen Access Assessment of the impact of the IARC Monograph Vol. 121 on the safety of the substance styrene (FCM No 193) for its use in plastic food contact materials EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP), Corresponding Author fip@efsa.europa.eu Correspondence: fip@efsa.europa.euSearch for more papers by this authorVittorio Silano, Search for more papers by this authorJosé Manuel Barat Baviera, Search for more papers by this authorClaudia Bolognesi, Search for more papers by this authorAndrew Chesson, Search for more papers by this authorPier Sandro Cocconcelli, Search for more papers by this authorRiccardo Crebelli, Search for more papers by this authorDavid Michael Gott, Search for more papers by this authorKonrad Grob, Search for more papers by this authorClaude Lambré, Search for more papers by this authorEvgenia Lampi, Search for more papers by this authorMarcel Mengelers, Search for more papers by this authorAlicja Mortensen, Search for more papers by this authorInger-Lise Steffensen, Search for more papers by this authorChristina Tlustos, Search for more papers by this authorHenk Van Loveren, Search for more papers by this authorLaurence Vernis, Search for more papers by this authorHolger Zorn, Search for more papers by this authorLaurence Castle, Search for more papers by this authorEmma Di Consiglio, Search for more papers by this authorRoland Franz, Search for more papers by this authorNicole Hellwig, Search for more papers by this authorMaria Rosaria Milana, Search for more papers by this authorKarla Pfaff, Member of the Working Group on 'Food Contact Materials' of the EFSA Panel on Food Contact Materials, Enzymes and Processing aids (CEP) until 31 July 2020.Search for more papers by this authorMaria Carfi, Search for more papers by this authorEllen Van Haver, Search for more papers by this authorGilles Rivière, Search for more papers by this author EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP), Corresponding Author fip@efsa.europa.eu Correspondence: fip@efsa.europa.euSearch for more papers by this authorVittorio Silano, Search for more papers by this authorJosé Manuel Barat Baviera, Search for more papers by this authorClaudia Bolognesi, Search for more papers by this authorAndrew Chesson, Search for more papers by this authorPier Sandro Cocconcelli, Search for more papers by this authorRiccardo Crebelli, Search for more papers by this authorDavid Michael Gott, Search for more papers by this authorKonrad Grob, Search for more papers by this authorClaude Lambré, Search for more papers by this authorEvgenia Lampi, Search for more papers by this authorMarcel Mengelers, Search for more papers by this authorAlicja Mortensen, Search for more papers by this authorInger-Lise Steffensen, Search for more papers by this authorChristina Tlustos, Search for more papers by this authorHenk Van Loveren, Search for more papers by this authorLaurence Vernis, Search for more papers by this authorHolger Zorn, Search for more papers by this authorLaurence Castle, Search for more papers by this authorEmma Di Consiglio, Search for more papers by this authorRoland Franz, Search for more papers by this authorNicole Hellwig, Search for more papers by this authorMaria Rosaria Milana, Search for more papers by this authorKarla Pfaff, Member of the Working Group on 'Food Contact Materials' of the EFSA Panel on Food Contact Materials, Enzymes and Processing aids (CEP) until 31 July 2020.Search for more papers by this authorMaria Carfi, Search for more papers by this authorEllen Van Haver, Search for more papers by this authorGilles Rivière, Search for more papers by this author First published: 14 October 2020 https://doi.org/10.2903/j.efsa.2020.6247 Requestor: European Commission Question number: EFSA-Q-2019-00686 Panel members: José Manuel Barat Baviera, Claudia Bolognesi, Andrew Chesson, Pier Sandro Cocconcelli, Riccardo Crebelli, David Michael Gott, Konrad Grob, Claude Lambré, Evgenia Lampi, Marcel Mengelers, Alicja Mortensen, Gilles Rivière, Vittorio Silano, Inger-Lise Steffensen, Christina Tlustos, Henk Van Loveren, Laurence Vernis and Holger Zorn. Competing interests: R. Franz declared that Fraunhofer institute at which he was employed provides advisory services to private business operators active in the sector on food contact materials. In line with EFSA's Policy on Independence (http://www.efsa.europa.eu/sites/default/files/corporate_publications/files/policy_independence.pdf) and the Decision of the Executive Director on Competing Interest Management (http://www.efsa.europa.eu/sites/default/files/corporate_publications/files/competing_interest_management_17.pdf), a waiver was granted to R. Franz regarding his participation to the EFSA's Working Group on Food Contact Materials (FCM WG) in accordance with Article 21 of the Decision of the Executive Director on Competing Interest Management. Pursuant to Article 21(6) of the above-mentioned Decision, the involvement of R. Franz is authorised as member in the FCM WG, allowing him to take part in the discussions and in the drafting phase of the scientific output, but he is not allowed to be, or act as, a chairman, a vice-chairman or rapporteur of the working group. Acknowledgements: The Panel wishes to thank the following members of the EFSA Scientific Committee cross-cutting working group on genotoxicity (ccWG Genotoxicity) and EFSA staff members for their support provided to this scientific output: Diane Benford, Gabriele Aquilina, Margherita Bignami, Rainer Guertler, Francesca Marcon, Elsa Nielsen, Josef Rudolf Schlatter, Christiane Vleminckx, Daniela Maurici, and Rositsa Serafimova. Note: The full opinion will be published in accordance with Article 10(6) of Regulation (EC) No 1935/2004 once the decision on confidentiality, in line with Article 20(3) of the Regulation, will be received from the European Commission. Some data on styrene migrating from copolymers into food simulants have been provided under confidentiality and it is redacted awaiting the decision of the Commission. Adopted: 9 September 2020 AboutSectionsPDF ToolsExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinked InRedditWechat Abstract The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP) was requested by the European Commission to re-evaluate the safety of styrene (FCM No 193) for use in plastic food contact materials (FCM) following the classification by the International Agency for Research on Cancer (IARC) as 'probably carcinogenic to humans'. The IARC Monograph pertains to hazard identification, based on studies on high-dose occupational exposures by inhalation and animal studies, also mainly by inhalation. The Panel considered that the IARC conclusions cannot be directly applied to the evaluation of risks for consumers from the oral exposure to styrene, but also concluded that, based on the data provided in the IARC Monograph and by the industry, a concern for genotoxicity associated with oral exposure to styrene cannot be excluded. The migration of styrene into foods packed in styrenic plastics is below 10 μg/kg for the majority of the foods, but up to 230 μg/kg was reported. Migration tends to be high for contact with fatty foods, and/or with high surface to volume ratios of the FCM. Dietary exposure of the consumers to styrene migrating from styrenic plastics was estimated in the order of 0.1 μg/kg body weight (bw) per day. It is in the same range as exposure from styrene present in foods as such. The dietary exposure (food component plus migration from styrenic plastics) is similar or lower than that by inhalation in the general population. Taking the human exposure data into account, the Panel concluded that a systematic review of genotoxicity and mechanistic data, comparative toxicokinetics and analysis of species differences is required for assessing the safety of styrene for its use in FCM. 1 Introduction 1.1 Background and Terms of Reference as provided by the requestor Terms of Reference as provided by the European Commission "In accordance with Article 12(3) of Regulation (EC) No 1935/200411 OJ L 338, 13.11.2004, p. 4., the European Commission asks EFSA to evaluate whether the authorisation of styrene (FCM No 193) as provided for in Table 1 of Annex I of Regulation (EU) No 10/2011, is still in accordance with the requirements of Regulation (EC) No 1935/2004. Styrene is authorised to be used as monomer and/or starting material for the manufacture of plastic food contact materials (FCM) and is currently listed in Annex I of Regulation (EU) No 10/2011, without a Specific Migration Limit (SML). New scientific evidence on the potential health effects of styrene was recently considered by the International Agency for Research on Cancer (IARC) in the reclassification of its carcinogenicity, where IARC concluded that styrene is 'probably carcinogenic to humans'.22 IARC Monograph volume 121: styrene, styrene-7,8-oxide and quinoline. The EFSA evaluation should assess whether the evidence examined by IARC leading to its conclusions, would have an impact on the safety of styrene in FCMs. To this end, EFSA should obtain the available information on styrene from IARC. In case the new evidence indicates that the present authorisation is no longer in accordance with the regulation, then EFSA should, if supported by the data, determine under what conditions the substance could be safely used. Addendum to the Terms of Reference On 22 July 2019, EFSA received from the European Commission a cover letter and the Styrene Technical Dossier put together and submitted to the Commission by a consortium of industry operators under the auspices of PlasticsEurope. To ensure that all available information is utilised in the styrene re-evaluation, the information submitted by PlasticsEurope needs to be also considered together with the IARC monograph in the styrene re-evaluation." 1.2 Interpretation of the Terms of Reference In 2019, IARC updated the evaluation of styrene (IARC, 2002) that had classified the substance as 'possibly carcinogenic to humans' (Group 2B). In the IARC Monograph Volume 121, published on 23 September 2019, IARC evaluated styrene and its metabolite styrene-7,8-oxide as 'probably carcinogenic to humans' (Group 2A). Furthermore, IARC considered that 'there is strong evidence that both styrene and styrene-7,8-oxide are genotoxic, and that this mechanism can also operate in humans'. Based on the new IARC classification, the European Commission asked EFSA to evaluate whether the new scientific evidence considered by IARC has an impact on the safety of styrene for use in plastic FCMs. In addition, the evaluation of the Technical Dossier submitted by Styrenics (a consortium of industry operators under the auspices of PlasticsEurope) on 22 July 2019 was considered as part of this mandate. The CEP Panel asked for support by the EFSA Scientific Committee cross-cutting working group on genotoxicity (ccWG Genotoxicity) to address the genotoxicity of styrene, in particular considering oral exposure. The ccWG Genotoxicity indicated the need to review not only the references considered by IARC and in the Styrene Technical Dossier, but to extend the literature search beyond these datasets. Since this analysis could not be completed in a short time and considering that styrene is in the high priority group of substances needing re-evaluation among those that are authorised for use in FCMs without an SML (EFSA, 2020), the CEP Panel proposed to address the mandate in two steps: First (within 1 year following the publication of the IARC Monograph), an opinion is provided based on the information available in the IARC Monograph and in the Styrene Technical Dossier, without appraising all individual papers referenced therein. This opinion also addresses the migration of styrene from styrenic plastics into food and dietary exposure estimates, as well as exposure to styrene from FCMs compared to other sources. A more comprehensive evaluation of the relevant literature is foreseen in the second phase to conclude on the genotoxic risk of styrene associated with the use of the substance in food contact materials, and, if appropriate, proposing safe limits for consumer exposure. For the evaluation of the exposure to styrene, data on FCMs other than plastics are of interest. Finally, for an assessment of what migrates from polystyrene and styrene copolymers, also oligomers and other related reaction products should be considered. 2 Data and methodologies 2.1 Data For this first step of the mandate, the following data have been considered: – the IARC Monograph Volume 121 on styrene, styrene-7,8-oxide and quinoline, published 23 September 2019 on the IARC website: http://publications.iarc.fr/582; – the Styrene Technical Dossier submitted in July 2019 by the industry consortium; – additional information provided by PlasticsEurope in response to requests from EFSA sent on 13 March 2020 (see 'Documentation provided to EFSA'); – archive material regarding the earlier assessment performed by the Scientific Committee on Food (SCF) provided by the European Commission on 22 January 2020 (SCF opinions/evaluations 1982, 1991; addenda to initial Technical Dossier 1995–2001). Some publications referenced in the IARC Monograph and the Styrene Technical Dossier were consulted. No comprehensive literature search was performed. Data used for the evaluation are: Non-toxicological data and information Chemical identity Physical and chemical properties Uses History of the authorisation Migration of the substance into simulants and foods Exposure Toxicological data Genotoxicity data as reported by the IARC Monograph and provided by the industry. 2.2 Methodologies The assessment was conducted in line with the principles laid down in Regulation (EC) No 1935/2004 on materials and articles intended to come into contact with food, the EFSA Guidance on transparency in the scientific aspects of risk assessment (EFSA, 2009) and considering the relevant guidance from the EFSA Scientific Committee. Data sources taken into consideration are listed in Section 2.11. 3 Assessment 3.1 History of the authorisation of styrene in FCMs In 1982, the Scientific Committee on Food (SCF) evaluated styrene and had no objection accepting the continued use of styrene in FCMs, while recommending to reduce the levels of styrene monomer residues as much as possible. Thus, in the Synoptic Document (European Commission, 2005), the SCF classification for styrene was set as 4B, allocated to 'substances for which an acceptable daily intake (ADI) or tolerable daily intake (TDI) could not be established, but which could be used if the levels of monomer residues in materials and articles intended to come into contact with foodstuffs are reduced as much as possible'. In the Directive 90/128/EEC33 OJ L 75, 21.3.1990, p. 19–40., the first Directive relating to plastic materials and articles intended to come into contact with foodstuffs, styrene was authorised to be used as monomer and/or starting substance for the manufacture of plastic FCMs without a Specific Migration Limit (SML). No restrictions are defined by the current listing of styrene in Annex I of Regulation (EU) No 10/2011. The substance can be used at up to 100% w/w to make all types of plastics intended for contact with all types of foodstuffs, without restrictions in contact time and temperature. The only limitation in use is linked with the sensory properties of styrene, given that in accordance with Article 3(c) of Regulation 1935/2004, materials and articles should not transfer their constituents to food in quantities which could bring about a deterioration in the organoleptic characteristics thereof. 3.2 Uses of styrene in FCM/conditions of use The vinyl C=C double bond of styrene can be polymerised to make polystyrene homopolymers. Styrene can also be polymerised with other unsaturated monomers to make a range of copolymers. Typical comonomers and their resulting copolymers are the thermoplastics made by addition polymerisation of styrene with acrylonitrile (styrene/acrylonitrile copolymers, SAN) and butadiene (acrylonitrile/butadiene/styrene copolymers, ABS). Other types of copolymers are the thermoset plastics made by mixed addition/condensation polymerisation of styrene with unsaturated polyesters (styrene/divinylbenzene cross-linked unsaturated polyester resins) and the copolymers made by reaction with acrylic acid (and its derivatives) to make styrene/acrylate resins. These polystyrene homopolymers and styrenic copolymers are made into a variety of materials and articles that are intended for either single use (e.g. food packaging) or repeated use (e.g. durable articles). These materials and articles are in turn used in contact with many different categories of food. Examples are: high impact polystyrene (HIPS) containers for dairy products, such as yoghurt; sheets and films for dairy products, take away foods, cutlery and tableware made of styrene-butadiene copolymer (SBC) thermoplastics and blends with general purpose polystyrene (GPPS); reusable kitchenware and cutlery, made of GPPS, HIPS, ABS or SAN; disposable plates and containers for hot foods like soups, e.g. for catering, HIPS; disposable wares for hot solid foods, made of foamed GPPS; cups for hot beverages, like coffee or tea, made from GPPS or expanded polystyrene (EPS); trays for packaging meat, poultry, cheese, fruits and vegetables, made of expanded (EPS) or extruded polystyrene (XPS); cold boxes for fisheries, food or beer, of EPS; kitchen appliances and machine parts thereof, of ABS; unsaturated polyester/epoxy vinylester/styrene polymers for food containers (vats, other large vessels) in industrial applications; can coatings for food and beverages; sealants, e.g. styrene-butadiene rubber (SBR) for can ends; polymer dispersions/lattices (e.g. styrene butadiene or styrene acrylate copolymers) used for coatings of paper and board, adhesives, overprint varnishes etc.; styrene as a solvent, cross-linking agent and reactive diluent in the production of glass-reinforced plastics. As can be seen from the non-exhaustive list above, the conditions of use of styrene polymers range typically from low temperature (refrigeration) for periods of days to few weeks, e.g. packaged fish, meat and dairy products, to elevated temperatures for short periods of time, e.g. vending cups for hot drinks or fast food take aways. 3.3 Non-toxicological data Chemical formula: C8H8 Molecular mass: 104 Da Chemical structure: 3.3.1 Physical and chemical properties44 Technical dossier/sections 1.1 and 2.1. The melting point of styrene is -30.6°C and the boiling point at standard atmospheric pressure is 145°–146°C. The octanol-water partition coefficient (log Po/w) is 2.95–3.02. Thermal decomposition of styrene starts above 450°C, which is above the maximum processing temperatures of styrenic plastics (ca. 300°C). Styrene has a sweet odour. – Odour thresholds for styrene in water range from 0.004 to 2.6 mg/L, depending on temperature (WHO, 2004); average taste threshold at 40°C: 0.12 mg/L; odour threshold at 60°C: 0.0036 mg/L (Alexander et al., 1982). – The threshold in milk products is 0.2–6 mg/kg, depending on fat content and the taste of the product itself (Tischner, 1993). – As provided by the Styrene Technical Dossier,55 Technical dossier/section 5.1. generally, concentrations above 1 mg/kg in foods bring about a deterioration of the organoleptic characteristics. The threshold level for organoleptic perception in an oil-in-water emulsion with 30% oil is about 2 mg/kg. In cream, styrene off-flavour was reported at 6 mg/kg. Styrenic plastics contain free styrene monomer at highly variable concentrations. For instance, Genualdi et al. (2014) found styrene in 24 food contact polystyrenes in the range of 9.3–3,100 mg/kg (mean 340 mg/kg). This styrene may consist of unreacted residues from polymerisation, but styrene can also be formed by depolymerisation during thermal processing of styrenic plastics to make materials and articles. 3.3.2 Specific migration66 Technical dossier/section 5.1 and Annexes 6–10. Migration into foods In three studies performed by the UK Ministry of Agriculture, Fisheries and Food (MAFF) in 1983, 1994 and 1999, styrene in foods was measured. In the first two studies, the sampling focused on foods packaged in styrenic plastics, but its presence in the foods before contact with the FCM was not checked. In the 1983 study (MAFF, 1983), retail foods and their styrenic plastic packaging materials were analysed for styrene. Styrene was determined in 133 samples using head space GC-MS. The samples comprised yogurts, creams, salads, coleslaws, soft cheeses, margarines, hot and cold beverages from dispensing machines, spreads, fresh and cooked meat, candied fruits, fresh strawberries and fast food take aways. Migration ranged from < 1 μg/kg to 200 μg/kg or μg/L, although in the majority of the foods (77%), it was below 10 μg/kg, and in 26% of the foods, it was below 1 μg/kg. Only three foods contained more than 50 μg/kg styrene: a dessert and two fresh meat products. In the 1994 survey of styrene in food (MAFF 1994), 248 samples of foods of a wide variety (food types, manufacturers, packaging types and pack sizes) were analysed. The sampling focused on foods packaged in styrenic plastics. In the majority of the samples, the styrene concentration ranged from below the detection limit (1–10 μg/kg, depending on the food) to 60 μg/kg. In two out of seven samples of 'low fat' table spread (margarine), a mean concentration of 97 μg/kg was reported, but in the other five, the concentrations were 20 μg/kg or less. In 22 samples of milk and cream sold as individual portions (~ 10 g) for tea or coffee, styrene concentrations ranged from 23 to 223 μg/kg, with a mean of 134 μg/kg. For all other food types, mean values were below 30 μg/kg. Within each food type, concentrations were higher in products with a high-fat content or small pack sizes (high surface to volume ratio, S/V). In the 1999 total diet study (TDS; MAFF, 1999), 100 composite food samples were analysed. Samples of individual foods in the various categories comprising the 20 UK-TDS food groups (Peattie et al., 1983) were purchased on different dates during 1997 from retail outlets in different parts of the UK. There was no special focus on samples packaged in styrenic plastics, since the recurring UK-TDS programme has a 'general purpose' character for investigating additives, contaminants, nutrients etc. The foods were prepared as for consumption (including cooking where appropriate) and combined into the 100 composite samples. Styrene was detected at up to 14 μg/kg food group. In a study performed by the Food and Drug Administration (FDA; Genualdi et al., 2014), migration of styrene into 24 food samples was measured. The polystyrenes contained 9.3–3,100 mg/kg styrene (mean of 340 mg/kg) and the migration into foods ranged from 2.6 μg/kg in raw chicken to 163 μg/kg in sandwich cookies. El-Ziney and Tawfik (2016) measured styrene in a range of Egyptian dairy products packed in polystyrene, with results ranging from 11 μg/kg (yogurt) to 102 μg/kg (butter). Philo et al. (1997) measured styrene-7,8-oxide, presumably formed by oxidation of styrene monomer, in polystyrene FCMs. Styrene-7,8-oxide was detected in 11 of 16 food packagings at up to 2.9 mg/kg. Assuming a migration pro-rata to the styrene migration from the plastic and 0.5–3.0 mg styrene oxide/kg packaging, its migration into food was estimated at 0.002–0.150 μg/kg. It is concluded that styrene migration into foods mostly remains below 10 μg/kg, but the highest concentration measured was 223 μg/kg. Higher migrations were found in high S/V packs and in contact with fatty food. Migration into simulants In the Styrene Technical Dossier, two sets of specific migration test reports were provided with different styrene-based polymers, one from 2001 and the other from 2013. In the 2001 study,77 Technical dossier/section 5.1 and Annexes 7, 10. rod and sheet test samples of styrene homopolymers and copolymers were tested for migration into the food simulants 3% acetic acid, 10% ethanol, olive oil and dewaxed sunflower oil. The contact conditions were 2 h at 70°C, 2 days at 40°C and 10 days at 5°C, 20°C and 40°C. The rods were tested by total immersion and the sheets by one side contact. For the analysis of styrene, headspace GC-MS was used. The highest migration of styrene was 590 μg/kg in olive oil after 10 days exposure at 40°C. Migrations into 3% acetic acid and 10% ethanol were three to five times lower. Migrations from rigid and expanded polystyrene (GPPS, HIPS vs. EPS) were in the same range, but those from SAN and ABS five to ten times lower. Taking into account the strongly varying concentrations of styrene in the polymer, presently available data did not enable to classify different polystyrenes and styrene copolymers by styrene migration. In the study performed in 2013,88 Technical dossier/section 5.1 and Annexes 6, 8, 9. migration tests were performed with styrene homopolymers (GPPS and HIPS) in olive oil for 10 days at 40°C, 50°C and 60°C with one-sided contact and in 50% ethanol for 10 days at 40°C and 50°C by total immersion. For the analysis of styrene, GC-FID was used for the olive oil and HPLC-PDA for the 50% ethanol in water simulant. The highest migration of styrene was 2,270 μg/kg (olive oil after 10 days exposure at 60°C). ■■■■■.99 Technical dossier/additional data April 2020. It is concluded that tests with simulants at standard conditions result in migration of styrene at up to several thousand μg/kg, which is substantially higher than the migration data reported in foods. The Panel noted that such tests refer to foreseeable worst-case uses and are not suitable for estimating typical oral exposure, including from foods kept under less severe contact conditions and with lower fat content. Furthermore, testing with 50% ethanol at elevated temperatures can swell polystyrene polymers, thus leading to increased (and possibly unrepresentative) migration values. Migration strongly depends on the free styrene content in the plastic. It increases with increasing temperature and is higher for fatty contact than for non-fatty contact. 3.3.3 Dietary exposure resulting from migration from styrenic plastics into food Based on migration data in food and the US/FDA consumption factor (CF) assuming that 10% of the food is packed in styrenic plastics, Tang et al. (2000) estimated the average annual exposure to styrene at 1.1–6.5 μg/kg bw or 80–450 μg/adult (70 kg bw). This corresponds to an average daily exposure of 0.003–0.017 μg/kg bw or 0.2–1.2 μg/adult. Using the migration data in foods from literature and consumption data from the Irish National Children's Food Survey (NCFS), Duffey and Gibney (2007) estimated the mean daily exposure of Irish children to styrene from styrenic plastics at 0.122 μg/kg bw when using the 90th percentile migration values and at 0.169 μg/kg bw when using the maximum value reported. Lickly et al. (1995, 1997), using a migration model, estimated the styrene exposure from the daily food in the USA packed in styrenic plastics to be 0.15 μg/kg bw per day. In a study submitted to FDA by the Plastics Foodservice Packaging Group (2015), a concentration of styrene of 2.20 μg/kg in food was attributed to plastic food packaging. Using the default assumption that a person weighing 60 kg may consume daily up to 1 kg of food in contact with the relevant FCM (European Commission, 2001), this concentration in the diet results in an estimated daily intake of approximately 0.04 μg/kg bw. It is concluded that the daily dietary exposure to styrene migrated from styrenic plastics is in the order of 0.1 μg/kg bw (0.003–0.15 μg/kg bw for adults, and at the 90th percentile 0.169 μg/kg bw for children). Most studies did not include the exposure to styrene from FCMs other than styrenic plastics. 3.3.4 Exposure to styrene present in food Styrene is present in many foods as such. It is not always clear whether it is a natural component or a biodegradation/fermentation product (e.g. from cinnamic acid). Concentrations vary widely: in fruits, vegetables, milk and meat, they were near the detection limit of 0.1 μg/kg, but much higher concentrations were determined in cinnamon (40,000 μg/kg) as well as in mouldy cheese (up to 5,000 μg/kg) and milled olives after some storage (230 μg/kg) (Tang et al., 2000). In 27 samples of cinnamon-flavoured hot cross buns, styrene concentrations ranged from < 10 to 767 μg/kg, with a mean of 26 μg/kg (MAFF, 1983). In the total diet study performed by MAFF in the UK in 1999 (MAFF, 1999), the dietary exposure to styrene was estimated at 0.03–0.05 μg/kg bw per day, based on the analysis of 100 composite samples. It did not distinguish the sources, i.e. it included styren
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