Measurement of Trace Elements in Marine Environmental Samples using Solution ICPMS. Current and Future Applications

Abstract

The strengths and weaknesses of using inductively coupled plasma mass spectrometer (ICPMS) measurements of samples in solution for marine environmental analyses using real world examples is discussed. ICPMS can detect nanogram per litre concentrations of trace elements but suffers from polyatomic interferences generated from the sample matrix. Most of the routine trace elements measured in marine biological tissue and sedimentdigests, with the notable exceptions of iron, chromium, vanadium, and selenium, are not subject to severe interferences. Low recoveries of trace elements from sediments are due to the inability of extraction acids to remove trace elements such as chromium and nickel from sediment matrices. The use of ICPMS offers the advantage that elements such as phosphorus, which previously required elaborate digestion procedures and a colorimetric determination, can be rapidly determined using nitric acid digestion alone. The use of flow injection coupled with ICPMS allows on-line preconcentration of trace metals and metalloids using chelation by ion-exchange resins or hydride generation and trapping as well as separation from matrix elements. Thus, the routine determination of trace elements and inorganic and methylated arsenic, antimony, mercury, and germanium species in open-ocean waters is possible. The coupling of HPLC and GC to ICPMS allows the measurement of metal and metalloid species in biological and sediment extracts. However, extraction of unaltered species from matrices presents a challenge. Many of the species found in the environmental samples are not known and analytical standards are not available. The concurrent use of HPLC-MS is needed to confirm these species.

Sampling, sample treatment and quality assurance issues for the determination of phosphorus species in natural waters and soils

“…Most methods described in Table 2 are based on spectrophotometric detection but ICP-MS and ICP-AES have, in recent years, been used to determine phosphorus in agricultural runoff waters and soils and results were comparable with spectrophotometric methods [128,129]. In addition, microwave digestion combined with ICP-MS detection has been used to determine phosphorus in marine environmental samples and plant leaves with good recoveries [130][131][132]. However microwave heating for batch sample digestion and in FI systems with spectrophotometric detection for on-line TDP and TP digestion [3] is less widely used than UV photo-oxidation or autoclaving.…”

Arsenic and selected elements in inter‐tidal and estuarine marine algae, south‐east coast, NSW, Australia

“…Internal standards were added on-line to compensate for any acid side effects and instrument drift. 14 The potential interference to arsenic (m/z 75) from 40 …”

Arsenic and selected elements in marine angiosperms, south‐east coast, NSW, Australia

“…The identity of these arsenoriboses was previously confirmed by high-performance liquid chromatography-mass spectrometry (HPLC-MS). 18 Trimethylarsoniopropionate (TMAP) was isolated in-house from the marine animal certified reference material, lobster hepatopancreas (TORT-2; NRC-CNRC). 19 …”