Abstract
Arsenic is an ubiquitous element that is present in the environment due to natural and anthropogenic processes. Marine samples are generally more concentrated in arsenic than terrestrial samples, with concentrations typically in the range of 1 to 100 mg kg-1. Arsenic has a complex chemistry and up to 100 naturally occurring arsenic species have so far been identified, both water-soluble and lipid-soluble compounds. Most research on arsenic and its chemical forms has so far focused on the water-soluble species, and a large set of data on occurrence and species exist. During the last decade an increased interest in the lipid-soluble arsenic species; the arsenolipids, has been seen. The most common techniques within arsenic speciation include use of high performance liquid chromatography coupled to the inductively coupled plasma mass spectrometry (HPLC-ICP-MS). However, for speciation analysis of arsenolipids, where organic solvents are required for the separation of species, the ICP-MS needs to be modified by addition of oxygen and use of low solvent flow. A modified ICP-MS set-up for analysis of intact arsenolipids was first applied in 20051. Since then, around 40 intact arsenolipids have been characterised in oils of fish, fish liver and marine algae. In this presentation, the current status and analytical challenges concerning quantitative and qualitative analysis of arsenolipids in marine oils will be discussed.