LGC sets the standards for metal extraction analysis


Environmental laboratories, extracting metals from soils and sediments using the ISO11466:1995 protocol, can now monitor the reliability and reproducibility of their results - thanks to a new reference material available through LGC Promochem.

LGC6189 River Sediment has been specifically developed by LGC to aid comparisons of metal extraction results between laboratories - something traditionally very difficult to do because most laboratories vary the time, temperature and acid combinations of the ISO11466:1995 protocol according to their own preferences.

Until now, there have been no standards against which laboratories can check their results for bias or monitor the ongoing performance of their metal extraction procedure, as available materials were not specific to the exact method conditions.

To address this, LGC has characterised the new reference material by extracting using the exact conditions specified in the ISO protocol and measuring the concentration of those metals that reached stable “extraction plateaus“ of concentration after the specified two hour reflux time. Measurement of the dissolved metal concentrations was carried out using inductively coupled plasma mass spectrometry (ICP-MS). A single primary standard - closely matched to the analyte concentration in the sample - was used to calibrate the procedure.

Once a laboratory has established the relationship between results obtained using its own metal extraction conditions and those obtained using the exact ISO procedure, the new LGC6189 reference material can then be used to monitor the ongoing performance of the laboratory’s protocol to ensure consistency and reproducibility.

LGC6189 is packaged in 30g units in screw-capped amber glass bottles. It comes with assessed values, with associated uncertainty, for arsenic, cadmium, chromium, copper, manganese, molybdenum, nickel, lead and zinc - as well as an indication of the mineral composition of the sediment.

For further information about LGC6189 River Sediment and related reference materials for extractable metals, contact -

LGC Promochem
Email: [email protected]