Element and Element Species Analysis

Fraunhofer IME has many years of experience in element and element species analysis. The focus is on determining total contents in organic matrices and aqueous samples as well as species analysis.

The following analytical methods are available for this purpose:

• ICP-MS (single quadrupole) and ICP-MS with triple quadrupole technology (ICP-QQQ) for determinations down to the ultra-trace range; increased interference control in MS/MS mode (reaction mode)
• Various couplings for element species analysis: HPLC-ICP-MS, GC-ICP-MS and IC-ICP-MS (all couplings also with ICP-QQQ)
• ICP-OES for simultaneous multi-element determinations
• Atomic absorption spectroscopy (AAS), including cold vapour AAS for mercury

Sample preparation includes digestion methods: for example, microwave digestion for organic matrices or extractions in accordance with relevant standards (such as the treatment of soils with aqua regia or ammonium nitrate solution).

The species determinations established at Fraunhofer IME include, among others:

• Methylmercury in biological samples
• Sulphur compounds in water
• Arsenic compounds in seafood
• Organotin compounds in environmental samples
• Cyclic methylsiloxanes in fish muscle
• Chromium(III)/chromium(VI) in soils
• Other elemental species in water and other environmental matrices

In addition to water solubility (OECD Guideline 105), the transformation and solubility behaviour of metals and metal compounds in aqueous media are also investigated in accordance with OECD Guidance document No. 29:

• Quantification of the extent and rate of formation of soluble ions or metal-containing species
• Coverage of the pH ranges required in the guideline
• Applicability of the T/D test system also for metallic nanoparticles
• If necessary, development of species-specific elemental analysis (coupling of suitable separation and detection methods)

In addition, the investigation of bioaccessibility may be necessary for metals and metal compounds. For this purpose, we determine the solubility of the test substances in simulated human body fluids (e.g. sweat or gastric acid).

The elemental analyses can be coupled with ecotoxicological questions (e.g. using established bioligand models). In accordance with regulatory requirements, metals and metal compounds are examined in bioconcentration tests (OECD Guideline 305) and in higher-tier ecotoxicological test systems (e.g. in microcosm studies on fate and effects).

The range of methods available at Fraunhofer IME enables problem-specific analysis.