The Government Chemist carried out several referee analyses for nitrofuran veterinary residues in shellfish and other crustaceans which led to recommendations for analysis and reporting.
The recommendations include:
- testing the inner core of animal meat in crustaceans, as semicarbazide (a nitrofuran metabolite) may occur naturally in the shell of crab, langoustines and shrimps
- for products in ice, the sample is thawed and the water drained away
- subtracting the measurement uncertainty from the mean result to yield a ‘not less than figure’ used for reporting ‘beyond reasonable doubt’