Download Malachite Green

MALACHITE GREEN
NOR MUAIZA BT. ABDUL MOKTY,
FOOD TECHNOLOGIST C44
INTRODUCTION
Malachite green (MG) is an N-methylated triphenylmethane dye that is used mainly industrially for leather,
wool, cotton, silk, jute, paper and certain fibres. For such purposes, large quantities of extremely variable
composition have been produced. About 10-15% of all dyes are lost directly to wastewater in the dyeing
process.
The chemical has been used routinely in some countries in aquaculture since the early 1930s and is considered by many in the fish industry to be an effective antifungal and antiprotozoal agent in fish, fish eggs and
crayfish. It is currently registered in some countries for use as a veterinary drug in ornamental fish, to
which it is applied as a topical antiseptic or to treat parasites, fungal infections and bacterial infections in
fish and fish eggs. Reported types of treatment of fish include dip treatment, flush treatment, sustained culture treatment and application in feed. Extremely wide ranges of concentrations and exposure times have
been used.
MG in water originating from contamination as a result of its industrial applications or from its illegal use
in aquaculture is efficiently taken up from the water by fish and distributed to all tissues. MG is metabolically reduced by fish to the persistent colourless metabolite, leucomalachite green (LMG), and possibly
other, as yet unidentified degradation products. The rate of excretion of MG (as LMG) from fish is dependent on the fat content of the fish. More LMG being retained in fatty fish than in lean fish. Therefore, when
fish that have been exposed to MG reach the consumer, the amount of LMG present in the fish is expected
to be higher than that of MG because of its longer elimination half-life.
REGULATION
SIDE EFFECT
In EU, the concept of the minimum required performance limit (MRPL) has been established for
several substances which have been expressly prohibited from use in food producing animals. MG is
not an authorized substance to use in food producing animals by EU regulation.There is no limit
stated for MG in Malaysian Food Regulation 1985.
Substances
•
Toxic to aquatic organisms and human.
•
Carcinogenic
•
Mutagenic
•
Teratogenic
•
Chromosomal fractures
Matrices
Sum of malachite green and Meat of aquaculture products
leucomalachite green
MRPL
Reference
2 (µg/kg)
Commission Decision
2004/25