Nitrofurans

Why in news?

The FSSAI has directed food safety officers across India to collect samples of both branded and unbranded eggs for testing after a viral video claimed the presence of nitrofuran residues.

• Nitrofurans – It is an antibiotic, banned on food-producing animals.
• Key Compounds and Their Uses
• The four primary parent compounds in this class include:
  • Nitrofurantoin - Primarily used in human medicine to treat and prevent uncomplicated urinary tract infections (UTIs).
  • Furazolidone - Traditionally used to treat bacterial diarrhoea, cholera, and Giardia.
  • Nitrofurazone (Nitrofural) - Used topically for skin infections, burns, and skin grafts.
  • Furaltadone - Historically used in veterinary medicine for poultry and livestock.
• Mechanism of Action - Nitrofurans work by entering bacterial cells, where they are reduced by bacterial enzymes (nitroreductases) into highly reactive electrophilic intermediates.
• These intermediates attack multiple targets simultaneously, including:
  • DNA and RNA - Causing genetic damage and inhibiting transcription.
  • Proteins - Disrupting protein synthesis and the citric acid cycle.
• This multi-target approach makes it difficult for bacteria to develop resistance compared to other antibiotics.
• Persistence - Although the parent drugs metabolise quickly (half-life of less than an hour), their side-chain metabolites (e.g., AOZ, AMOZ, SEM, AHD) bind to tissues and can persist for weeks.
• Health risks - They are considered carcinogenic and genotoxic, meaning they can damage DNA and increase cancer risk.
• Residues persist - Even after stopping use, nitrofuran metabolites remain in animal tissues (meat, eggs, fish).

References

1. New Indian Express | Nitrofurans' presence in Egg
2. Times of India | Test Eggs for banned antibiotics