Key points
Success in public health is measured by things that don’t happen.
This statement was made by Professor Sarah O’Brien, chair of the Food Standards Agency’s (FSA’s) Advisory Committee on the Microbiological Safety of Food (ACMSF) last month following a tortuous debate about the risk from Shiga toxin producing E.coli (STEC) in raw and ready-to-eat foods.
It neatly sums up the dilemma facing food risk advisers: nobody knows when you get it right – but you are front page news when you get it wrong.
The FSA executive had asked the ACMSF to offer its advice regarding the identification of a particular gene, called stx, in food products as an indicator for STEC contamination, which might present an “unacceptable risk” to consumers.
Why is this important? Because the presence of the gene could be detected in a few days compared with up to five days needed to isolate a bacterial strain. This would allow short shelf-life foods to be removed from the supply chain before they potentially caused food poisoning incidents.
The downside is that there are many different STEC strains, which are evolving all the time, and not all are equally pathogenic. Thus, by using gene detection, foods might be removed unnecessarily from sale at considerable cost to manufacturers.
For well over an hour the ACMSF members agonised over their decision. Much of the debate centred around what is an ‘unacceptable risk’. Because, as one member pointed out, the risk is not just a minor tummy upset for some vulnerable individuals it could result in kidney failure and other life-threatening consequences.
Unacceptable risks (Return to top)
In the end, the ACMSF agreed that while it was unacceptable for the gene to be present there was currently insufficient evidence to state that it presented an unacceptable risk when appropriate control measures were taken into account.
As a consequence, the committee could not confirm that positive detection of the gene would allow the assessment of the potential risk to public health.
Some might argue this demonstrates scientists dancing on the head of a pin and a reluctance to commit to taking a firm decision. A more generous view would be that it illustrates the complexities of microbiology and the difficult decisions scientists have to wrestle with: weighing up the balance between risk and proportionality of control measures.
It’s not an academic argument by any means. In one form or another, cost versus the benefits of taking or not taking certain actions came up time and again throughout Food Manufacture Group’s one-day food safety conference held at the Lowry in Manchester on September 29.
The event, titled ‘Safer food & drink – from the harvest to the home’, was chaired by Professor Colin Dennis, president of the US Institute of Food Technologists, and sponsored by Sartorious Intec, Mettler Toledo, Alcontrol Laboratories, Checkit, Klipspringer and the Institute of Food Research.
Crime prevention (Return to top)
Andy Morling, head of the FSA’s new National Food Crime Unit (NFCU), in only his third public outing, kicked off the day by pointing out that, given the limited resources available, a balance needed to be struck between crime prevention and crime detection.
Put simply, it’s a matter of creating barriers to temptation for minor transgressions or “non-compliance” with food safety rules which, if not challenged, could snowball into full-scale criminality.
While Morling was not convinced that the UK’s organised crime syndicates were currently involved in food crime in the UK yet, “organised crime will be a problem if not tackled now”, he said. Describing the classic circle of “motivation, opportunity and means”, which lay behind most food crime, he said: “For an offence, you need all three things.” By reducing or removing one or more of these factors, it was unlikely to happen, he argued.
As well as making use of “open” and “closed” sources of data available to his unit, he stressed the imperative of the NFCU working closely with the food and drink industry to share intelligence so-called “humint” – human intelligence – and the need for greater reporting of food crime.
“Humint is the stuff that is out there and we want to encourage people to come to us,” said Morling. “It could be somebody who is working for a business that has gone seriously rogue and they want to put their hands up and say, I can’t live with this any longer. That’s the sort of person I want to talk to.
“But I also want criminals to come to me and say I have got information for you. It may not be motivated by something that is altruistic. They may be wanting to deflect attention from their own criminality, but I don’t care. I want information about serious crime happening in the food industry.
Information sharing (Return to top)
“I want to have a new relationship with industry in the NFCU; one based on mutual respect and trust. Because I believe there is specific information out there that industry has that will be valuable to my team.”
While there might be reluctance within the industry to share this information, he added: “I will provide whatever industry wants in terms of undertakings that I will handle their data in a way that is professional and respects their commercial interests.”
Professor Chris Elliott’s report following the 2013 horsemeat scandal had called for the NFCU to have investigative powers. However, Morling said the police were best resourced at the moment to carry out this work. But he didn’t discount it being taken over by the unit at some stage in the future.
“Responsibility for investigating crime in this country is the police service and I am comfortable our cases will be warmly received by police forces around the country,” said Morling.
“If I’m wrong about that and time shows that the police response isn’t what we want it to be then we will review the situation. We have committed ourselves to reviewing it at some point in the next two years. So, it’s not never, it’s just not now.”
Richard Leathers, from Campden BRI’s food safety management team, followed Morling by describing how food businesses could use threat analysis critical control point techniques to reduce the chances of falling foul of food fraud incidents in the future, whether that be malicious contamination by disgruntled employees or adulteration and substitution of ingredients within the supply chain.
Use of informatics (Return to top)
The use of informatics, or the interrogation and analysis of ‘big data’ held on computer systems was a recurring theme throughout the day.
Whether it is to detect chemical contamination risks or emerging pathogens, the ability to drill down and analyse data using computer algorithms and other screening techniques will enable the industry to pick up trends that just would not be possible by human intervention alone.
Matthew Sharman, head of food science at the Food and Environmental Research Agency (FERA) in York, described techniques developed by FERA to isolate individual chemical contaminants – often unknown and unsuspected chemicals – from huge swathes of apparent “noise” produced during sample analysis.
“What we are talking about is having sufficient knowledge to make informed decisions,” said Sharman. Aspects such as toxicity, occurrence and usage data need to be taken into account, he added.
“The key thing really for me is data. Yes, we have some data on the known chemicals which are there but we have little data on the unknowns, the potential threats.
“What we need to make the system stronger is to increase our use of data and with increased use of data we can increase our knowledge.”
He used the example of drilling down into data of residues of veterinary medicines present in foods, which showed some foods over the legal limit in 60% of cases, when the overall results suggested a compliance level of 99.5%.
Testing methods (Return to top)
“I think we should do things differently going forward. That could be testing fewer samples but doing it in a better way,” he suggested. At the moment, surveillance wasn’t risk-based and this made life very easy for those wanting to commit fraud, he added.
“We should think about testing for things we don’t know about,” he said. “We are often testing processed foods. That actually makes life much more difficult. So I would recommend testing upstream rather than downstream wherever possible.”
To identify the unknowns, Sharman proposed testing for everything and using computer analysis to identify the rogue elements within ingredients.
“The question for me is what is in the noise; what are the needles in the haystack,” said Sharman. “To do that there has been a step change in the technology over the past three or four years. What this means is we can go from targeted compounds to non-targeted compounds. So more profiling technologies are becoming available.”
The future for food safety and food fraud would appear to hinge around the use of informatics.