Risk of Heavy Metal Contamination in Krill Oils

Abstract

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.

Keywords

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

Project Number

17.SAĞ.BİL.12

Krill Yağlarında Ağır Metal Kontaminasyon Riski

Abstract

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.

Keywords

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

Supporting Institution

Afyon Kocatepe Üniversitesi Sağlık Bilimleri Enstitüsü

Project Number

17.SAĞ.BİL.12

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