News
27-Nov-2006 - LGC improving the accuracy of tin analysis in
canned foods
LGC introduces a new certified reference standard for
characterising tin, lead and cadmium in tomato paste
A new reference material now available from LGC Promochem is set
to improve the reliability and reproducibility of data on the
levels of tin, cadmium and lead found in food. ERML-BC084a Tomato
paste certified for tin, lead and cadmium was produced by LGC in
response to the widespread problem of achieving accuracy of tin
data amongst the analytical laboratories involved in the FAPAS®
proficiency testing scheme.
Canned foods can be contaminated with certain metals during the
preparation and packaging process. Additionally, manufacturers are
permitted to add metals that function as additives. Tin chloride
(E512) is often used in small quantities as an antioxidant and to
aid colour retention in canned and bottled foods. However,
excessive levels of tin in foodstuffs can cause gastric irritation,
so a regulatory limit of 200 mg/kg of tin in canned food has been
set by the European Union along with permitted levels for lead and
cadmium.
In collaboration with LGC, the UK Central Science Laboratory (as
part of their FAPAS® scheme), found an unexpected common bias in
the measurement results amongst laboratories determining tin levels
in food. LGC was asked to provide an independent reference value
for the proficiency testing samples using Inductively Coupled
Plasma Mass Spectrometry (ICP-MS) with isotopic dilution (IDMS),
which revealed a bias of over 20% in the consensus value. The LGC
IDMS method has been verified as part of a high level international
comparison.
The new matrix certified reference material ERML-BC084a Tomato
paste certified for tin, lead and cadmium was produced for use in
the validation of methods for the determination of tin, lead and
cadmium in a fruit or vegetable based material. It may also be used
for monitoring the ongoing performance of a method. Production of
this reference material was supported under contract with the
Department of Trade and Industry as part of the VAM (Valid
Analytical Measurement) programme. LGC recently gained UKAS
accreditation to ISO Guide 34 and ISO/IEC 17025 for the production
of reference materials.
ERML-BC084a is now available from LGC Promochem in 50g units
packaged in amber glass bottles with tamper evident closures, and
finally provides analytical laboratories everywhere with a means of
checking for bias in their results and establishing traceability
for their data. For further information about ERML-BC084a Tomato
paste certified for tin, lead and cadmium, please contact LGC
Promochem by email at askus@lgcpromochem.com or call
+44 (0)20 8943 8480.
Notes to Editors