Nano-Food Packaging: An Overview of Market, Migration Research, and Safety Regulations

Journal of Food Science

Volumn 80, Issue 5, 2015, Pages R910-R923

  Bumbudsanpharoke, Nattinee ^a   Ko, Seonghyuk ^a  

^a Yonsei University   (South Korea)

Author keywords

Food packaging; Migration; Nanoparticles; Risk assessment; Safety

Indexed keywords

NANOMATERIAL; NANOPARTICLE;

ANALYSIS; FOOD CONTAMINATION; FOOD PACKAGING; HEALTH; HUMAN; LAW; LEGISLATION AND JURISPRUDENCE; PROCEDURES; PRODUCT SAFETY; SAFETY;

CONSUMER PRODUCT SAFETY; FOOD CONTAMINATION; FOOD PACKAGING; HEALTH; HUMANS; LEGISLATION, FOOD; NANOPARTICLES; NANOSTRUCTURES; SAFETY;

EID: 84929129984     PISSN: 00221147     EISSN: 17503841     Source Type: Journal    
DOI: 10.1111/1750-3841.12861     Document Type: Article

References (107)

1. Abdelhalim A, Abdellah A, Scarpa G, Lugli P. 2013. Fabrication of carbon nanotube thin films on flexible substrates by spray deposition and transfer printing. Carbon 61:72-9.
2. Abdellah A, Abdelhalim A, Loghin F, Kohler P, Ahmad Z, Scarpa G, Lugli P. 2013. Flexible carbon nanotube based gas sensors fabricated by large-scale spray deposition. IEEE Sens J 13(10):4014-21.
3. Adams M. 2012. U. S. FDA's regulatory approach to nanotechnology in food contact substances. ILSI Europe Workshop on Outlook and Challenges of Nanotechnologies for Food Packaging Brussels; 8-10 February 2012. Md., U.S.A.: U. S. Food and Drug Administration - Office of Food Additive Safety.
4. Aguilera JM. 2014. Where is the nano in our foods? J Agr Food Chem 62:9953-56.
5. Almeida, C. 2013. Brazil struggles to regulate emerging nanotechnology. Science and technology for development news and analysis website. Available from: http://www.scidev.net/global/technology/feature/brazil-struggles-to-regulate-emerging-nanotechnology.html#. Accessed 2014 November 06.
6. Amico ED. 2004. Chasing nanocomposites. Chem Week 10:6-9.
7. Arora A, Padua GW. 2010. Review: nanocomposites in food packaging. J Food Sci 75(1):R43-9.
8. Astley, M. 2011. Food contact nanomaterial regulations inadequate - report. Foodproductiondaily website. Available from: http://www.foodproductiondaily.com/Safety-Regulation/Food-contact-nanomaterial-regulations-inadequate-report. Accessed 2014 November 06.
9. Banks, M. 2013. Risk of nanotechnologies in food chain found to be negligible. The Parliament-Brussels Office Weblog. Available from: http://brussels.cta.int/index.php?option=com_k2&view=item&id=7611:risk-of-nanotechnologies-in-food-chain-found-to-be-negligible-&utm_source=brussels.cta.int+feb+2014&utm_campaign=16523ac1c1-CTA_Brussels_Office:Newsletter_393_11_4_2014&utm_medium=email&utm_term=0_f50a0786c3-16523ac1c1-78365481. Accessed 2014 06 November.
10. Belli, B. 2012. Eating nano: Processed foods and food packaging already contain nanoparticles - Some of which could be harmful to our health. The Environmental Magazine Website. Available from: http://www.emagazine.com/includes/print-article/magazine/9623/. Accessed 2015 January 31.
11. Blasco C, Pico Y. 2011. Determining nanomaterials in food. Trend Anal Chem 30(1):84-99.
12. 2 nanocomposite food packaging film by in vitro and in vivo tests. LWT-Food Sci Technol 50(2):702-6.
13. Bott J, Störmer A, Wolz G, Franz R. 2012a. Migration potential of nanoscale silver particles in food contact polyolefins. The 5th international Symposium on Food Packaging; Berlin; 14 to 16 November 2012. Freising, Germany: Fraunhofer Institute for Process Engineering and Packaging.
14. Bott J, Störmer A, Wolz G, Franz R. 2012b. Studies on the migration of titanium nitride nanoparticles in polymers. the 5th international Symposium on Food Packaging; Berlin; 14 to 16 November 2012. Freising, Germany: Fraunhofer Institute for Process Engineering and Packaging.
15. Brody AL, Bugusu B, Han JH, Sand CK, McHugh TH. 2008. Scientific status summary. Innovative food packaging solutions. J Food Sci 73(8):R107-16.
16. Chaudhry Q, Castle L. 2011. Food applications of nanotechnologies: An overview of opportunities and challenges for developing countries. Trends Food Sci Technol 22(11):595-603.
17. Chaudhry Q, Scotter M, Blackburn J, Ross B, Boxall A, Castle L, Aitken R, Watkins R. 2008. Applications and implications of nanotechnologies for the food sector. Food Addit Contam A 25(3):241-58.
18. 2 nanoparticles. Exp Cell Res 305(1):51-62.
19. Chun AL. 2009. Will the public swallow nanofood? Nat Nanotechnol 4(12):790-1.
20. [CNBC] Consumer News and Business Channel, 2014. Global nano-enabled packaging market for food and beverages industry will reach $15.0 billion in 2020: Persistence market research. CNBC Website. Available from: http://www.cnbc.com/id/102011212. Accessed 2015 January 14.
21. Cooper TA. 2013. Developments in plastic materials and recycling systems for packaging food, beverages and other fase-moving consumer goods. In: Farmer N, editor. Trends in packaging of food, beverages and other fast-moving consumer goods (FMCG): Markets, materials and technologies. Philadelphia, Pa.: Woodhead Publishing Limited. p. 79.
22. Cushen M, Kerry J, Morris M, Cruz-Romero M, Cummins E. 2012. Nanotechnologies in the food industry-Recent developments, risks and regulation. Trends Food Sci Technol 24(1):30-46.
23. Cushen M, Kerry J, Morris M, Cruz-Romero M, Cummins E. 2013. Migration and exposure assessment of silver from a PVC nanocomposite. Food Chem 139(1-4):389-97.
24. Department of Science and Technology of the Republic of South Africa, 2014. Address by the Minister of Science and Technology, Naledi Pandor MP, at the launch of a nanotechnology spectrometer (TOF-SIMS), Rhodes University, November 2014. Department of Science and Technology of the Republic of South Africa Website.
25. Di Maio L, Scarfato P, Milana MR, Feliciani R, Denaro M, Padula G, Incarnato L. 2013. Bionanocomposite polylactic acid/organoclay films: Functional properties and measurement of total and lactic acid specific migration. Packag Technol Sci 27(7):535-47.
26. Dong S, Chen X, Gu L, Zhou X, Xu H, Wang H, Liu Z, Han P, Yao J, Wang L, Cui G, Chen L. 2011. Facile preparation of mesoporous titanium nitride microspheres for electrochemical energy storage. ACS Appl Mater Interfaces 3(1):93-8.
27. Duncan TV. 2011. Applications of nanotechnology in food packaging and food safety: barrier materials, antimicrobials and sensors. J Colloid Interface Sci 363(1):1-24.
28. Duran N, Marcato PD. 2013. Nanobiotechnology perspectives. Role of nanotechnology in the food industry: a review. Int J Food Sci Technol 48(6):1127-34.
29. Echegoyen Y, Nerin C. 2013. Nanoparticle release from nano-silver antimicrobial food containers. Food Chem Toxicol 62:16-22.
30. EcoSynthetix. 2014. EcoSphere Biopolymer. EcoSynthetix website. Available from: http://ecosynthetix.com/our-biochemicals/ecosphere. Accessed 2015 January 31.
31. [EFSA] European Food Safety Authority. 2011. Guidance on the risk assessment of the application of nanoscience and nanotechnologies in the food and feed chain. EFSA J 9(5):2140.
32. [EFSA] European Food Safety Authority. 2012. Scientific opinion on the safety evaluation of the substance, titanium nitride, nanoparticles, for use in food contact materials. EFSA J 10(3):2641.
33. European Commission. 2004. Regulation (EC) No. 1935/2004 of the European Parliament and the Council of 27 October 2004 on materials and articles intended to come into contact with food and repealing directives 80/590/EEC and 89/109 EEC. Off J Eur Union 338:4.
34. European Commission. 2007. Commission Directive 2007/19/EC of 2 April 2007 amending Directive 2002/72/EC relating to plastic materials and articles intended to come into contact with food and Council Directive 85/572/EEC laying down the list of simulants to be used for testing migration of constituents of plastic materials and articles intended to come into contact with foodstuffs. Off J Eur Union 97:50.
35. European Commission. 2009a. Commission Regulation (EC) No 450/2009 of 29 May 2009 on active and intelligent materials and articles intended to come into contact with food. Off J Eur Union 135:3.
36. European Commission. 2009b. Commission Regulation (EC) No 975/2009 of 19 October 2009 amending Directive 2002/72/EC relating to plastic materials and articles intended to come into contact with foodstuffs. Off J Eur Union 274:3.
37. European Commission. 2009c. Regulation (EC) No 1223/2009 of the European Parliament and the Council of 30 November 2009 on cosmetic products. Off J Eur Union 342:59.
38. European Commission. 2010. Towards A Strategic Nanotechnology Action Plan (SNAP) 2010-2015. Available from: http://ec.europa.eu/research/consultations/snap/report_en.pdf. Accessed 2014 November 2014
39. European Commission. 2011. Commission Regulation (EU) No 1282/2011 of 28 November 2011amending and correcting Commission Regulation (EU) No 10/2011 on plastic materials and articles intended to come into contact with food. Off J Eur Union 328:22.
40. European Commission. 2013. Food labelling - EU rules 2014. European Commission Website. Available from: http://ec.europa.eu/food/food/labellingnutrition/foodlabelling/proposed_legislation_en.htm. Accessed 2015 January 14.
41. European Commission. 2014. Commission Regulation (EU) No 202/2014 amending Regulation (EU) No 10/2011 on plastic materials and articles intended to come into contact with food. Off J Eur Union 62:13.
42. Farhoodi M, Mousavi SM, Sotudeh-Gharebagh R, Emam-Djomeh Z, Oromiehie A. 2014. Migration of aluminum and silicon from PET/clay nanocomposite bottles into acidic food simulant. Packag Technol Sci 27(2):161-68.
43. [FAO/WHO] Food and Agriculture Organization of the United Nations/World Health Organization. 2010. Expert meeting on the application of nanotechnologies in the food and agriculture sectors: Potential food safety implications meeting report. Rome, Italy: FAO/WHO. p. 107.
44. [FAO/WHO] Food and Agriculture Organization of the United Nations/World Health Organization. 2012. Joint FAO/WHO Seminar on Nanotechnologies in food and agriculture meeting report. Rome, Italy: FAO/WHO. p. 12.
45. [FAO/WHO] Food and Agriculture Organization of the United Nations/World Health Organization. 2013. State of the art on the initiatives and activities relevant to risk assessment and risk management of nanotechnologies in the food and agriculture sectors: FAO/WHO technical paper report. Rome, Italy: FAO/WHO. p. 48.
46. [FSA] Food Standards Agency. 2014. European Food Information to Consumers Regulation No 1169/2011 (FIC). 2014 December 14 ed. Food Standard Ageny Website. Available from: https://www.food.gov.uk/enforcement/regulation/fir/labelling. Accessed 2015 January 07
47. Fletcher N, Bartholomaeus A. 2011. Regulation of nanotechnologies in food in Australia and New Zealand. Int Food Risk Anal J 1(2):33-40.
48. Foladori G, Invernizzi N. 2013. Inequality gaps in nanotechnology development in Latin America. J Arts Hum 2(3):35-45.
49. Foladori G, Lau EZ. 2014. The regulation of nanotechnologies in Mexico. Nanotech L Bus 11:164.
50. Fortunati E, Peltzer M, Armentano I, Torre L, Jimenez A, Kenny JM. 2012. Effects of modified cellulose nanocrystals on the barrier and migration properties of PLA nano-biocomposites. Carbohydr Polym 90(2):948-56.
51. Food Standards Australia New Zealand (FSANZ) 2014. Summary of responses to FSANZ's industry packaging survey. Parliament of Australia Website. Available from: http://www.aph.gov.au/~/media/Committees/clac_ctte/estimates/bud_1415/DoH/answers/SQ14-000586_Att2.pdf. Accessed 2015 January 13.
52. Garnett MC, Kallinteri P. 2006. Nanomedicines and nanotoxicology: some physiological principles. Occup Med Oxford 56(5):307-11.
53. Geiser M, Rothen-Rutishauser B, Kapp N, Schurch S, Kreyling W, Schulz H, Semmler M, Im Hof V, Heyder J, Gehr P. 2005. Ultrafine particles cross cellular membranes by nonphagocytic mechanisms in lungs and in cultured cells. Environ Health Perspect 113(11):1555-60.
54. Han M, Li S. 2008. Study on the medical application of silver material. Micro- and Nanotechnology: Materials, Processes, Packaging, and Systems IV; Melbourne, Australia; 09 December 2008. Washington, United States: Society of Photo-Optical Instrumentation Engineers.
55. Hatzigrigoriou N, Papaspyrides C. 2011. Nanotechnology in plastic food-contact materials. J Appl Polym Sci 122(6):3719-38.
56. Hoet PH, Brüske-Hohlfeld I, Salata OV. 2004. Nanoparticles-known and unknown health risks. J Nanobiotechnol 2(1):12.
57. Honeywell International Inc. 2013. Aegis® OXCE Barrier Nylon Resin. Honeywell International Inc Website. Available from: http://www.honeywell-pmt.com/sm/aegis/products-n2/aegis-ox.html. Accessed 2015 January 31.
58. Huang Y, Chen S, Bing X, Gao C, Wang T, Yuan B. 2011. Nanosilver migrated into food-simulating solutions from commercially available food fresh containers. Packag Technol Sci 24(5):291-7.
59. Hwang M, Lee EJ, Kweon SY, Park MS, Jeong JY, Um JH, Kim SA, Han BS, Lee KH, Yoon HJ. 2012a. Risk assessment principle for engineered nanotechnology in food and drug. Toxicol Res 28(2):73-9.
60. Hwang M, Park MS, Kweon SY, Lee EJ, Jeong JY, Um JH, Kim KJ, Yun HJ. 2012b. Information profiling for exposure assessment of engineered nanomaterials in nano-food and drug. Available from: http://iufost.org.br/sites/iufost.org.br/files/anais/01991.pdf. Accessed 2014 November 05
61. Kay L, Shapira P. 2009. Developing nanotechnology in Latin America. J Nanopart Res 11(2):259-78.
62. Khemani K, Moad G, Lascaris E, Li G, Simon G, Habsuda J, Shanks R, Genovese A, Gunaratne W, Nichols L, inventors; Plantic Technologies Ltd., assignee. 2008. Starch nanocomposite materials. USA Patent US20100307951 A1.
63. Klass CP. 2007. New nanoparticle latex offers natural advantage. Paper360 Magazine 2(1):30-31.
64. Landsiedel R, Ma-Hock L, Kroll A, Hahn D, Schnekenburger J, Wiench K, Wohlleben W. 2010. Testing metal-oxide nanomaterials for human safety. Adv Mater 22(24):2601-27.
65. Lin QB, Li B, Song H, Wu HJ. 2011. Determination of silver in nano-plastic food packaging by microwave digestion coupled with inductively coupled plasma atomic emission spectrometry or inductively coupled plasma mass spectrometry. Food Addit Contam A 28(8):1123-8.
66. 2-polyethylene composite packaging into food simulants. Food Addit Contam A 31(7):1284-90.
67. Liu JF, Yu SJ, Yin YG, Chao JB. 2012. Methods for separation, identification, characterization and quantification of silver nanoparticles. Trend Anal Chem 33:95-106.
68. Lue JT. 2007. Physical properties of nanomaterials. Encyclopedia of nanoscience and nanotechnology. American Scientific Publishers X:1-46.
69. Magnuson BA, Jonaitis TS, Card JW. 2011. A brief review of the occurrence, use, and safety of food-related nanomaterials. J Food Sci 76(6):R126-33.
70. Majeed K, Jawaid M, Hassan A, Abu Bakar A, Khalil HPSA, Salema AA, Inuwa I. 2013. Potential materials for food packaging from nanoclay/natural fibres filled hybrid composites. Mater Design 46:391-410.
71. Marambio-Jones C, Hoek EMV. 2010. A review of the antibacterial effects of silver nanomaterials and potential implications for human health and the environment. J Nanopart Res 12(5):1531-51.
72. Markarian J. 2005. Automotive and packaging offer growth opportunities for nanocomposites. Plast Add Comp 7(6):18-21.
73. Martin, J. 2014. EPA takes action to protect public from an illegal nano silver pesticide in food containers; cites NJcompany for selling food containers with an unregistered pesticide warns large retailers not to sell these products. Available from: http://yosemite.epa.gov/opa/admpress.nsf/596e17d7cac720848525781f0043629e/6469952cdbc19a4585257cac0053e637!OpenDocument. Accessed 2014 December 05.
74. Meyer D. 2013. How carbon nanotubes could save you from spoiled food. GIGAOM Website. Available from: https://gigaom.com/2013/09/26/how-carbon-nanotubes-could-save-you-from-spoiled-food. Accessed 2014 November 05
75. Mohanty AK, Misra M, Nalwa HS. 2009. Packaging nanotechnology. Los Angeles, Calif.: American Scientific Publishers.
76. Momin JK, Jayakumar C, Prajapati JB. 2012. Potential of nanotechnology in functional foods. Emir J Food Agricult 25(1):10.
77. Nanocor. 2008. Nanocor product lines. Available from: http://www.nanocor.com/products.asp. Accessed 2015 January 14.
78. Neethirajan S, Jayas DS. 2011. Nanotechnology for the Food and Bioprocessing Industries. Food Bioprocess Technol 4(1):39-47.
79. [NIA] Nanotechnology Industries Association. 2011. Opportunities & risks in nanomedicine - how to build an infrastructure in support of the next generation of health care; 29th - 31st august 2011. 5° ENIFarMed; São Paulo; 29-31 August 2011. Brussels, Belgium: Nanotechnology Industries Association.
80. Oberdorster G, Maynard A, Donaldson K, Castranova V, Fitzpatrick J, Ausman K, Carter J, Karn B, Kreyling W, Lai D, Olin S, Monteiro-Riviere N, Warheit D, Yang H, Group IRFRSINTSW. 2005. Principles for characterizing the potential human health effects from exposure to nanomaterials: elements of a screening strategy. Part Fibre Toxicol 2(1):8.
81. Persistence Market Research. 2014. Global market study on nano-enabled packaging for food and beverages: Intelligent packaging to witness highest growth by 2020. Persistence Market Research Website. Available from: http://www.persistencemarketresearch.com/market-research/nano-enabled-packaging-market.asp. Accessed 2015 January 14.
82. Peters R, ten Dam G, Bouwmeester H, Helsper H, Allmaier G, von der Kammer F, Ramsch R, Solans C, Tomaniova M, Hajslova J, Weigel S. 2011. Identification and characterization of organic nanoparticles in food. Trend Anal Chem 30(1):100-12.
83. Picó Y, Blasco C. 2012. Nanomaterials in food, Which way forward? In: Barcelo D, Farré M, editors. Analysis and risk of nanomaterials in environmental and food samples. Great Britain: Elsevier. p. 305.
84. Plantic Technologies Limited. 2007. Cadbuer Schweppes and the Plantic R1 Tray. Plantic Website. Available from: http://www.plantic.com.au/Case%20Studies/Plantic_Cadbury_CS.pdf. Accessed 2015 January 21.
85. Qian G, Jarus D, Zabrocki V, inventors; Google Patents, assignee. 2009. Use of organoclay in HDPE nanocomposites to provide barrier properties in containers and film. U.S. Patent US7629406 B2.
86. Rasouli F, Zhang W, inventors; Philip Morris Usa Inc., assignee. 2006. Nanoscale materials. U.S. Patent US20060286239 A1.
87. Rubilar O, Diez MC, Tortella GR, Briceno G, Marcato PD, Duran N. 2014. New strategies and challenges for nanobiotechnology in agriculture. J Biobased Mater Bioenergy 8(1):1-12.
88. Schmidt B, Katiyar V, Plackett D, Larsen EH, Gerds N, Koch CB, Petersen JH. 2011. Migration of nanosized layered double hydroxide platelets from polylactide nanocomposite films. Food Addit Contam A 28(7):956-66.
89. Sekhon BS. 2010. Food nanotechnology-an overview. Nanotechnol Sci Appl 3(1):1.
90. Silvestre C, Duraccio D, Cimmino S. 2011. Food packaging based on polymer nanomaterials. Prog Polym Sci 36(12):1766-82.
91. Simon P, Chaudhry Q, Bakos D. 2008. Migration of engineered nanoparticles from polymer packaging to food-a physicochemical view. J Food Nutr Res 47(3):105-13.
92. Song H, Li B, Lin Q-B, Wu H-J, Chen Y. 2011. Migration of silver from nanosilver-polyethylene composite packaging into food simulants. Food Addit Contam A 28(12):1758-62.
93. Stephanie, S. 2013. Study looks at particles used in food. The New York Times Website. Available from: http://www.nytimes.com/2013/02/06/business/nanoparticles-in-food-raise-concern-by-advocacy-group.html?_r=0. Accessed 2014 November 05.
94. Tager J. 2014. Nanomaterials in food packaging: FSANZ fails consumers again. Chain Reaction (122):16-17.
95. Takeuchi MT, Kojima M, Luetzow M. 2014. State of the art on the initiatives and activities relevant to risk assessment and risk management of nanotechnologies in the food and agriculture sectors. Food Res Int 64:976-81.
96. Thanh NVK, Phong NTP. 2008. Investigation of antibacterial activity of cotton fabric incorporating nano silver colloid. ASEAN Workshop on Advanced Materials Science and Nanotechnology; Nha Trang, Viet Nam; 15 to 21 September 2008. Beijing, China: IOP Publishing.
97. Thies C. 2012. Nanotechnology as delivery system in the food, beverage and nutraceutical industries. In: Huang Q, editor. Nanotechnology in the food, beverage and nutraceutical industries. Philadelphia, Pa.: Woodhead Publishing Limited. p. 208.
98. Tuinier R, de Kruif CG. 2002. Stability of casein micelles in milk. J Chem Phys 117(3):1290-95.
99. [USEPA] United States Environmental Protection Agency. 2013. Nanomaterials EPA is assessing. The United States Environmental Protection Agency Website. Available from: http://www.epa.gov/nanoscience/quickfinder/nanomaterials.htm. Accessed 2015 January 13.
100. [USFDA] United States Food and Drug Administration. 2011. Draft guidance for industry: dietary supplements: new dietary ingredient notifications and related issues. 2011 July ed. Maryland. Available from: http://www.fda.gov/Food/GuidanceRegulation/GuidanceDocumentsRegulatoryInformation/DietarySupplements/ucm257563.htm. Accessed 2014 November 06.
101. [USFDA] United States Food and Drug Administration. 2014a. CFR-Code of federal regulations title 21. Maryland. Available from: http://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/Databases/ucm135680.htm. Accessed 2014 November 05.
102. [USFDA] United States Food and Drug Administration. 2014b. Guidance for industry: assessing the effects of significant manufacturing process changes, including emerging technologies, on the safety and regulatory status of food ingredients and food contact substances, including food ingredients that are color additives. Available from: http://www.fda.gov/Food/GuidanceRegulation/GuidanceDocumentsRegulatoryInformation/IngredientsAdditivesGRASPackaging/ucm300661.htm. Accessed 2014 November 05.
103. Venugopal J, Ramakrishna S. 2005. Applications of polymer nanofibers in biomedicine and biotechnology. Appl Biochem Biotechnol 125(3):147-58.
104. Wagner C. 2013. Nanomaterials. Food Packaging Forum Organization Website. Available from: http://www.foodpackagingforum.org/Food-Packaging-Health/Nanomaterials. Accessed 2014 November 06.
105. Whitworth, J. 2013. Migration factors of nanosilver in PVC packaging studied. Foodproductiondaily Website. Available from: http://www.foodproductiondaily.com/Packaging/Migration-factors-of-nanosilver-in-PVC-packaging-studied. Accessed 2014 November 06.
106. Zeng QH, Yu AB, Lu GQ, Paul DR. 2005. Clay-based polymer nanocomposites: research and commercial development. J Nanosci Nanotechnol 5(10):1574-92.
107. Zhang L, Chen F, An H, Yang H, Sun X, Guo X, Li L. 2008. Physicochemical properties, firmness, and nanostructures of sodium carbonate-soluble pectin of 2 Chinese cherry cultivars at 2 ripening stages. J Food Sci 73(6):N17-N22.