The demand for multi-mycotoxin
Claire Milligan, ER-Biopharm-Rhône, R-Biopharm AG, An der neuen Bergstraße 17, 64297 Darmstadt, Germany,
Mycotoxins are toxic secondary metabolites
produced by moulds growing on food and
feed products which can infect agricultural
crops during growth, harvest, storage or processing.
Cereal grains are extremely susceptible to fungal
infection and co-occurrence of more than one mycotoxin
is common. However, the growth of the mould
is not necessarily related to the formation of mycotoxins
as the formation depends on conditions such
as humidity, moisture, temperature and rainfall. In
addition, mycotoxins are particulary stable and may
be present in the food when the mould is no longer
present or even after processing.
Another route of contamination can be during
harvest or transportation by using the same equipment
or trucks to handle and ship different commodities,
such as cereals or spices. Only one of those
commodities needs to be infected for the spread of
mycotoxins to progress.
Mycotoxins can also pass along the foodchain
when animals are fed with contaminated feed. Studies
show that cows which are exsposed to aflatoxins (B1,
B2, G1 and G2) through their feedstuff, produce milk
which is contaminated with aflatoxin M1 and or M2.
The presence of mycotoxins in the food chain is a
major concern and therefore needs to be controlled.
There is a growing awareness of the potential hazards
of these substances, which can cause severe toxic effects
at relatively low levels in food and feed. They
can also cause illness and even death in humans and
Because of the importance of cereals in the everyday
human diet and in animal feed, mycotoxins are tightly
regulated in many countries around the world. In the
EU, aflatoxins, deoxynivalenol, zearalenone, ochratoxin
and fumonisin are all regulated in cereals and cereal
products, with one limit applying to unprocessed cereals
and a lower limit being applied to cereals intended
for direct human consumption. There are some reductions
in toxin levels during processing such as milling,
but as the toxins tend to concentrate in the fractions
such as bran there are consequent risks for animal feed.
As a number of toxins are regulated in cereals it
makes sense to consider multi-mycotoxin methods. In
these instances labs are considering measuring mycotoxin
levels by liquid chromatography with mass spectrometry.
LC-MS/MS is an analytical method used to
detect and quantify substances at trace levels, and offers
the advantage of being efficient and sustainable
for a number of applications and most importantly is
very sensitive. Given the very low legislated levels for
many mycotoxins LC-MS/MS is a powerful tool however,
it does have a drawback; the analytical result is
strongly influenced by presence of the matrix. These
so-called matrix effects cause a measurement of uncertainty
where components in the matrix reduce or
enhance the efficiency of ionisation. This leads to a
under or overestimate of the analyte concentration
and thus to uncertain results. Using appropriate tools,
these matrix effects can either be reduced, eliminated
or compensated for.
One option is to use matrix-matched standards,
which allows the analyst to correct for ionisation effects.
These are typically used in conjunction with solid
phase clean-up columns where the blank material
and the actual sample are processed in the same way
and analysed together. The matrix effects can be easily
subtracted afterwards since the standard will be effected
by the matrix effects just like the sample. While
giving a precise result you are having to perform two
analysis (sample and standard). Using SPE columns
will help to reduce the matrix effects but unfortunate