Scientists at Reading Scientific Services (RSSL) say they have won the race to develop a reliable method for detecting semicarbazide in metal lids
Scientists at Reading Scientific Services (RSSL) say they have won the race to develop a reliable method for detecting semicarbazide in metal lids.
Using a technique based on LC-MS, RSSL claims a detection limit of 10 parts per billion (ppb). Semicarbazide (SEM) emerged as a potential food risk in July 2003, when the European Food Safety Authority (EFSA) alerted member states to its presence in some foods sold in jars.
These included baby food, fruit juices, jams and conserves, honey, pickles and sterilized vegetables, mayonnaise, mustard, sauces and ketchups.
At the time, it was uncertain whether it was migrating from PVC sealing rings, or whether it had been formed as a result of chemical reactions that took place during the analysis itself.
According to EFSA, a potential source of SEM is the use of azidocarbonamide as a blowing agent for the foamed plastics used in gaskets.
However, this link has not been established.
The fear concerning migration is that SEM is reported to be a mutagen and carcinogen in laboratory animals, although no toxic effects have been reported in humans. Interestingly, SEM is also a breakdown product of the veterinary drugs known as nitrofurans.
Although not implicated in the recent EFSA findings, it is the case that the presence of nitrofurans and their breakdown products is banned in food sold in the EU. Hence it is important to know whether the SEM is appearing from migration, or arising from the test.
RSSL can now give a definitive answer to this question.
"Reliable information is needed before the industry can decide an appropriate response to this potential food safety risk," says Sonia Puri of RSSL. "This new method means that clients can test their products and assess their vulnerability to SEM contamination, before deciding whether a change in packaging design is required or not."
