Risk of Heavy Metal Contamination in Krill Oils

Yıl 2021, Cilt 14, Sayı 4, 408 - 414, 31.12.2021

Filiz ERDEN KIZILIRMAK Recep ASLAN İbrahim Sadi ÇETİNGÜL Özlem Yildiz GÜLAY Mehmet Şükrü GÜLAY

https://doi.org/10.30607/kvj.960071

Öz

Different omega-3 sources have been widely used as a portion of supplementary food in recent years. One of the popular sources of omega-3 fatty acids is krill oil. It is readily available and commonly being used in developed countries. Thus, the aim of the current study was to examine the contents of commercially available krill oils sold in the markets. For this purpose, the free-fatty acid levels, peroxide contents, and the presence of some heavy metals were determined for commercially available krill oils. A total of 11 different krill oil brands randomly selected and purchased from different pharmacies. The chemical analysis was carried out at a food analysis laboratory that has been accredited by the Turkish Accreditation Agency. Our results indicated that the fatty acid contents of the commercial krill oils tested varied to quite an extent, but within the tolerable limits in 10 out of 11 samples. The peroxide content of the samples differed from 10 to 30 meq O2/kg-oil. The mercury (0.1 mg/kg) and cadmium (1.0 mg/kg) levels were up to the standard limits set by Codex Alimentarius for food supplements. On the other hand, all products tested contained more than the tolerable limits of lead (0.08 mg/kg), and only 1 sample had arsenic levels measured below acceptable limits (0.1 mg/kg). As a result, none of the krill oil collected through random sampling could provide the required European Union standards. It suggests that the manufacturers overlooked some issues while producing krill oils. This may pose a potential threat to public health in the long term.

Anahtar Kelimeler

fatty acid composition, heavy metal contamination, krill oil, peroxide levels

Krill Yağlarında Ağır Metal Kontaminasyon Riski

Öz

Son yıllarda gıda takviyesi olarak farklı omega-3 kaynakları yaygın olarak kullanılmaktadır. Omega-3 yağ asitlerinin popüler kaynaklarından biri de kril yağıdır. Kolayca temin edilebilir olan bu yağlar, gelişmiş ülkelerde yaygın olarak kullanılmaktadır. Bu nedenle, mevcut çalışmanın amacı, piyasada bulunan kril yağlarının genel özelliklerini incelemektir. Bu amaçla ticari olarak temin edilebilen bazı krill yağlarında serbest yağ asidi seviyeleri, peroksit içerikleri ve bazı ağır metallerin varlığı araştırılmıştır. Farklı eczanelerden rastgele seçilen ve satın alınan toplam 11 kril yağı markasından alınan numunelerin kimyasal analizleri Türk Akreditasyon Kurumu tarafından akredite edilmiş bir gıda analiz laboratuvarında gerçekleştirilmiştir. Elde edilen sonuçlar, test edilen ticari kril yağlarının yağ asidi içeriğinin oldukça büyük ölçüde değişse de 11 numuneden 10'unda tolere edilebilir sınırlar içinde olduğunu göstermiştir. Numunelerin peroksit içeriği, 10 ila 30 meq O2/kg-yağ arasında bulunmuştur. Civa (0,1 mg/kg) ve kadmiyum (1,0 mg/kg) seviyeleri, gıda takviyeleri için Codex Alimentarius tarafından belirlenen standart limitleri içerisindeydi. Öte yandan, test edilen tüm ürünler, tolere edilebilir kurşun sınırlarından (0,08 mg/kg) daha fazlasını içerirken, yalnızca 1 numunede kabul edilebilir sınırların (0,1 mg/kg) altında arsenik seviyeleri görüldü. Sonuç olarak, rastgele örnekleme yoluyla toplanan kril yağlarının hiçbiri gerekli Avrupa Birliği standartlarını sağlayamadı. Bu durum üreticilerin kril yağları üretirken bazı konuları gözden kaçırdığını düşündürmektedir. Bu, uzun vadede halk sağlığı için potansiyel bir tehdit oluşturabilir.

Anahtar Kelimeler

Yağ asidi bileşimi, ağır metal kirliliği, krill yağı, peroksit seviyeleri

Kaynakça

• Atkinson A, Siegel V, Pakhomov E, Rothery P. Long-term decline in krill stock and increase in salps within the Southern Ocean. Nature. 2004; 432(7013):100-103. https://doi.org/10.1038/nature02996.
• Bettina M, Veronica F, Citlali G, Katrin S, Angus A, Susanne S, Boris C, Ulrich F, Alejandro O, Ulrich B. Physiology, growth, and development of larval krill Euphausia superbain autumn and winter in the Lazarev Sea, Antarctica. Limnol Oceanogr. 2009; 54(5): 1595–1614. https://doi.org/10.4319/ lo.2009.54.5.1595.
• Bang HO, Dyerberg J, Nielsen A. Plasma lipid and lipoprotein pattern in Greenlandic West-coast Eskimos. Lancet. 1971; 297:1143-1146. https://doi.org/10.1016/S0140-6736(71)91658-8.
• Bargagli R. Environmental contamination in Antarctic ecosystems. Sci Total Environ. 2008; 400:212–226. https://doi.org/10.1016/j.scitotenv.2008.06.062.
• Codex Alimentarius. General Standard for Contaminants and Toxins in Food and Feed. CXS 193-1995. Adopted in 1995, Revised in 2009, and amended in 2019.
• Codex Standards 329-2017. Codex standard for fish oils. Codex Alimentarius Commission. Adopted 2017.
• Corsolini S, Covaci A, Ademollo N, Focardi S, Schepens P. Occurrence of organochlorine pesticides (OCPs) and their enantiomeric signatures, and concentrations of polybrominated diphenyl ethers (PBDEs) in the Adélie penguin food web, Antarctica. Environ Pol. 2006; 140(2): 371-382. https://doi.org/10.1016/j.envpol.2005 .04.039.
• Covaci A, Voorspoels S, Vetter W, Gelbin A, Jorens PG, Blust R, Neels H. Anthropogenic and naturally occurring organobrominated compounds in fish oil dietary supplements. Environ Sci Technol. 2007; 41 (15):5237-5244. https://doi.org/10.1021/ es070239g.
• Farooqui T, Farooqui AA. Aging: an important factor for the pathogenesis of neurodegenerative diseases. Mech Ageing Develop. 2009; 130(4): 203-215.https://doi. org/10.1016/j.mad.2008.11.006.
• Kennicutt II MC, Chown SL, Cassano JJ, et al. A roadmap for Antarctic and Southern Ocean science for the next two decades and beyond. Antarctic Sci. 2015; 27:3-18. https://doi.org/ 10.1017/S0954102014000674.
• Li F, Ma C, Zhang P. Mercury Deposition, Climate Change and Anthropogenic Activities: A Review. Front Earth Sci. 2020; 8:316. https://doi.org/10.3389/feart. 2020.00316.
• Liu K, Hou SG, Wu SY, Zhang WB, Zou X, Yu JH, Song J, Sun XC, Huang RH, Pang HX, Wang JJ. Assessment of heavy metal contamination in the atmospheric deposition during 1950-2016 AD from a snow pit at Dome A, East Antarctica. Environ Poll 268: Part: B: 2021;115848. https://doi.org/10.1016/j.envpol.2020.115848
• NISTAER, National Institude of Science and Thecnology-Antarctic Environmental Research. 2014. Annual activity report-2010.
• Nicol S, Endo Y. Krill fisheries of the world. FAO Fisheries Technical Paper. 1997; No. 367. Rome, FAO.
• Phleger CF, Nelson MM, Mooney BD, Nichols PD. Interannual and between species comparison of the lipids, fatty acids and sterols of Antarctic krill from the US AMLR Elephant Island survey area. Comp Biochem Physiol Part B: Biochem Mol Biol. 2002;131(4):733-747. https://doi.org/ 10.1016/S1096-4959(02)00021-0.
• Reiss CS, Walsh J, Goebel ME. Winter preconditioning determines feeding ecology of Euphausiasuperba in the Antarctic Peninsula. Mar Ecol Prog Ser. 2015; 519: 89-101. https://doi.org/ 10.3354/meps11082.
• Schiermeier, Q. Ecologists fear Antarctic krill crisis. Nature. 2010; 467 (7311): 15. https://doi.org/10.1038/467015a.
• Schmidt K, Atkinson A, Pond DW, Ireland LC. Feeding and overwintering of Antarctic krill across its major habitats: The role of sea ice cover, water depth, and phytoplankton abundance. Limnol Oceanogr. 2014; 59(1): 17-36. https://doi.org/ 10.4319/lo.2014.59.1.0017
• Schuchardt, JP, Schneider I, Meyer H, Neubronner J, von Schacky C, Hahn IA. Incorporation of EPA and DHA into plasma phospholipids in response to different omega-3 fatty acid formulations - a comparative bioavailability study of fish oil vs. krill oil. Lipids Health Dis. 2011; 10:145. https://doi.org/ 10.1186/1476-511X-10-145.
• Simopoulos AP. The Importance of the Omega-6/Omega-3 Fatty Acid Ratio in Cardiovascular Disease and Other Chronic Diseases. Exp Biol Med. 2008; 233(6): 674-688. https://doi.org/ 10.3181/0711-MR-311
• Subhavana KL, Qureshi A, Chakraborty P, Tiwari AK. Mercury and Organochlorines in the Terrestrial Environment of Schirmacher Hills, Antarctica. Bull Environ Contam Toxicol. 2019; 102:13-18. https://doi.org/10.1007/s00128-018-2497.
• Sun D, Cao C, Li B, Chen H, Cao P, Li J, Liu Y. Study on combined heat pump drying with freeze-drying of Antarctic krill and its effects on the lipids. J Food Proc Engineer. 2017; 40(6), e12577. https://doi.org/10.1111/jfpe.12577.
• Tilseth S, Høstmark Ø. New method for making krill meal. 2015; US Patent 20150050403 A1.
• Tou JC, Javzynski J, Yi-Chen C. Krill for Human Consumption: Nutritional Value and Potential Health Benefits. Nutr Rev. 2007; 65(2):63-77. https://doi.org/ 10.1111/j.1753-4887.2007.tb00283.x.
• Vacchi M, Koubbi P, Ghigliotti L, Pisano E. Sea-ice interactions with polar fish: focus on the Antarctic silverfish life history. In Guido di Prisco; Cinzia Verde (eds.). The Impacts of Global Change on Biodiversity. Adaptation and Evolution in Marine Environments. 1. Springer Science & Business Media.2017; pp. 51-73.
• Xie D, Gong M, Wei W, Jin J, Wang X, Wang X, Jin Q. Antarctic Krill (Euphausia superba) Oil: A Comprehensive Review of Chemical Composition, Extraction Technologies, Health Benefits, and Current Applications. Compr Rev Food Sci Food Saf. 2019; 18:514-534. https://doi.org/10.1111/1541-4337.12427.
• Xie, D, Jin, J, Sun J, Liang L, Wang X, Zhang W, Wang X, Jin Q. Comparison of solvents for extraction of krill oil from krill meal: Lipid yield, phospholipids content, fatty acids composition and minor components. Food Chem. 2017; 233:434-441. doi: 10.1016/j.foodchem.2017.04.138.
• Xu Q, Chu Z, Gao Y, Mei Y, Yang Z, Huang Y, Yang L, Xie Z, Sun L. Levels, sources and influence mechanisms of heavy metal contamination in topsoils in Mirror Peninsula, East Antarctica. Environ Poll. 2020; 257:113552. https://doi.org/ 10.1016/j.envpol.2019.113552.
• Yashodhara BM, Umakanth S, Pappachan JM, Bhat SK. Kamath R. Choo BH. Omega-3 fatty acids: a comprehensive review of their role in health and disease. Postgrad Med J. 2009; 85:84-90. https://doi.org/ 10.1136/pgmj.2008.073338.
• Yin FW, Liu XY, Fan XR, Zhou DY, Xu WS, Zhu BW, Murata YY. Extrusion of Antarctic krill (Euphausiasuperba) meal and its effect on oil extraction. Int J Food Sci Technol. 2015; 50(3):633-639. https://doi.org/10.1111/ijfs.12673.