NOW scientists publish test method to accurately identify and measure inorganic arsenic in krill

November 27, 2019

NOW (Bloomingdale, IL) Methods Development team published a test method that accurately identifies the presence and levels of inorganic arsenic in krill oil.1 A ubiquitous element in the environment, its toxicity depends only on total concentration, but more so on the chemical form of the element. Inorganic arsenic is considered the most toxic, while organically bound species are considered to have lower or no toxicity in humans.

A monograph released by the Food Chemicals Codex (FCC) in late 2017 set limits for inorganic arsenic, but the methods defined are not able to accurately differentiate between the chemical species of arsenic compared to higher sensitivity and specificity speciation methods such as HPLC-ICP-MS. The complexity of the krill oil matrix also requires suitable sample preparation to liberate arsenic species and allow for precise quantification or inorganic arsenic.

“We determined that available test methods did not go far enough in ensuring that krill oil we were sourcing for our supplements met our purity and safety standards,” said Aaron Secrist, NOW’s vice president of Quality and Regulatory Affairs, in a press release. “We published the method in keeping with NOW’s long-standing practice of sharing test methods we develop with the industry.”


1. Banaszewski K et al. “Arsenic Speciation in Krill and Other Marine Oils by Liquid Chromatography−Inductively Coupled Plasma-Mass Spectrometry.” Spectroscopy, vol. 34, no. 9 (2019): 8-17