Belgium: We Have a Problem
What did testing laboratories learn from the Ethylene Oxide (EO) contamination scandal that rocked the European food industry last summer? And what are the future challenges around EO that analytical scientists need to prepare for? To celebrate the launch of LGC AXIO Proficiency Testing’s new Ethylene Oxide in Sesame sample, we investigate the causes of the crisis, and how laboratory scientists were at the forefront of the emergency response.
In the summer of 2020, a team of Belgian quality controllers sent alarm bells ringing throughout the European food industry.
They had just analysed various lots of imported sesame seeds from India - and detected dangerous residual levels of the toxic chemical Ethylene Oxide (EO).
EO has been banned from food use in the European Union since 1991, because of its genotoxic effects on humans. But the levels of EO that scientists discovered in some of the seed samples were up to 200 times the Maximum Residue Limits (MRLs) that apply across Europe. According to a report by the EU’s Reference Laboratories, at least one sample recorded a residue level of 186 mg/kg - or 3,720 times European MRLs.
Ethylene Oxide is one of the world’s most common chemicals – widely used in manufacturing to produce items such as antifreeze, detergents, fibres and bottles, as well as for sterilising medical equipment. And, while the process is not legal in Europe, it is sometimes employed elsewhere as a fumigant to control insects in spices, seasonings, and foodstuffs - rather than using high-temperature processes that could damage the products themselves.
When EO used on foods evaporates, however, it creates a potentially dangerous residue called 2-chloroethanol (2-CE) – a substance that, even at low exposure doses, can have devastating consequences on human health. Sustained exposure to EO causes damage to the brain and nervous system, as well as increasing the risks of lymphoid and breast cancer - leading the US National Institute of Health, the Environmental Protection Agency and other leading scientific bodies to declare it a human carcinogen.
Despite being banned for 30 years in Europe, EO is still employed legally by the US spice industry to prevent microbial contaminants such as Salmonella, E. coli, yeast, mould, coliforms and other pathogens. But this use is subject to strict residue limits: nowadays, the USA and Canada both set their MRLs for EO and 2-CE in spices, dried herbs, dried vegetables and oily seeds at seven and 940 parts per million, respectively.
The Indian exporters may also have employed EO as a “counter measure” against salmonella and other fecal bacteria - the presence of which has led to “numerous border rejections” of Indian sesame intended for the EU in the last 20 years. But crucially, the 2-CE residues found in the contaminated batches were all significantly over the EU MRL of 0.05mg/kg - their levels mostly ranging from 0.1 to 10mg/kg, or between two and 200 times the legal limit.
The Belgian quality controllers had, meanwhile, sparked a full-blown product recall emergency across Europe - since contaminated sesame seeds had already been “delivered to several member states and used for the production of various processed foodstuffs.” A month after Belgium raised the alarm, a meeting of EU food crisis coordinators learned that the “incriminated seeds” had already reached 24 Member States and nine ‘third countries’. And within three months, around 140 safety notifications concerning EO in sesame from India had appeared on the portal of the EU’s Rapid Alert System for Food and Feed (RASFF) - arriving from 19 countries covering an area from Spain to Russia, and from the Baltic to the Mediterranean.
National food safety teams also took action - alerting manufacturers whose products may have included sesame from the contaminated batches, instructing them to withdraw those products from sale and issue recall notices where necessary. The authorities told citizens who had the products not to consume them and return them to their point of sale for a refund.
But as sesame seeds are used in many sectors of the food industry, thousands of popular products were affected - including cereals, chocolate, biscuits, bread, crackers, sesame oil and bagels. A number of market-leading brands and supermarkets were forced into the expensive and reputationally damaging process of recalling popular items from shelves across Europe.
Today, almost a year after the contaminated seeds were first discovered, the impact of the Belgian lab’s findings is still being felt. As of July 2021, there had been more than 500 safety notifications concerning EO in food products across Europe.
The European Commission has also strengthened customs checks on sesame seeds from India - in the short-term checking 50 per cent of Indian sesame seeds arriving at the EU border - as well as increasing tests at border control posts.
Meanwhile, it remains unclear how long Indian suppliers have been using pesticides – intentionally or otherwise - to fumigate sesame seeds. At present, this is a question that the EU’s Reference Laboratories says “will need to be investigated” although the RASFF Crisis Coordinators believe that “the use of Ethylene Oxide seems to be very frequent in India.” Belgium also announced at the crisis meeting in November that one trader had been “blocked preventatively” from importing to the EU.
In November 2020, a report by the European Spice Association (ESA) also raised the possibility that the use of EO may have spread from sesame seeds to imported herbs and spices. Data provided by member companies showed that about seven per cent of all analyses were above the Maximum Residue Level for ethylene oxide - leading ESA to restate its commitment to a due diligence programme, including regular testing for EO and 2-CE residues. Some member states at the November 2020 RASFF crisis coordinators’ meeting also called for “reinforced vigilance on other products like pepper and spices for which past analysis also showed presence of ethylene oxide.”
The role played by quality controllers during the sesame seeds scandal - and the ongoing risks posed by EO/2-CE to both consumer safety and brand reputation - has emphasised vividly the need for laboratories to continue getting their analyses right.
By participating in proficiency testing regularly, you can have confidence in the measurement of your results.
For 40 years, LGC AXIO Proficiency Testing has been a trusted partner for laboratories working to keep food safe for everyone.
We move with the world’s changing demands, which is why we’ve expanded our Quality in Food Chemistry Scheme (QFCS) and launched a new sample to support your laboratory’s quantitative analysis of Ethylene Oxide.
Our PT-FC-857 Ethylene Oxide in Sesame sample is supplied as 10 grams of sesame paste, with Ethylene Oxide and 2-chloroethanol as the target analytes.
Drawing on decades of proficiency testing expertise and our truly global reach, AXIO is your perfect partner in proficiency testing.
Head to lgcstandards.com/AXIO to find out more and place your order.
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