Agriculture Reference
In-Depth Information
However, a considerable number of studies have consistently sustained the
belief that its use may determine relevant primary and secondary toxicological
effects, of various kinds. Among the major side effects, we can indicate those
related to the spermatogenesis, cardiovascular apparatus and blood mass,
changes in the immunological action to (sensitization reactions), their
hepatotoxicity and neurotoxicity and, particularly, their mutagenic potential,
both tumorigenic and carcinogenic [12].
Given the genotoxic possibility, the global use of nitrofurans as mass
veterinary medicines in therapeutic actions (1950-1995), particularly in pigs
and poultry, is considered a potentially severe Public Health Problem.
3.
C
URRENT
S
TATUS
Nitrofurans, particularly FZD, FTD, NFT, NFS and NFZ, belong to a class
of synthetic broad spectrum antibiotics which all contain a characteristic 5-
nitrofuran ring [15].
Prior to the mid 1990s, nitrofuran drugs have been used in food animal
production within the European Union (EU). However, due to the concerns
about their carcinogenicity and genotoxic effects [9], the use of NFT, NFZ and
FTD in food animal production was prohibited throughout the European Union
(Council Regulation (EEC) nº 2901/93 of 18 October 1993) [16].
Subsequently, and as a result of similar concerns, the use of FZD in food-
producing animals was similarly prohibited in 1995 (Commission Regulation
(EC) nº 1442/95 of 26 June 1995) [17]. More recently NFS has been
prohibited for use as a feed additive in Council Regulation (EC) nº 1756/2002
of 23 September 2002. Until then, NFS had been the last antibiotic that was
available and permitted for the prevention of histomoniasis (black head
disease) in turkeys.
Prior to the introduction of the ban on their use, most Member States set
up analytical methods to detect residues of the parent nitrofuran drugs in
compliance with the EU requirement (Council Directive 96/23/EC 1996) [18]
to establish National Surveillance Schemes for veterinary drug residues.
However, it is now known that this strategy is ineffective, because of the
low tissue concentrations and short half-life of the nitrofuran parent drugs and
their marked instability in vivo [19]. In contrary and as the protein bound
metabolites may persist in animal tissues for a long time, they can be used as
the markers for long term detection of the illegal use of these compounds in
food production animals.
