Risk assessment of use of cracked eggs in Canada

In 1992, Agriculture and Agri-Food Canada (AAFC) amended its Egg Regulations to restrict movement of Canada C eggs (cracks) to federally registered processed egg stations for pasteurization. This was questioned by egg producers and some provinces on economic grounds. It was also in conflict with long-standing practices of marketing eggs in some provinces to retail stores, bakeries, restaurants and institutions or at the farm gate. In order to determine how much of a risk these eggs were to human health, AAFC requested that the Health Protection Branch (HPB) of Health Canada (HC) conduct a risk assessment. On the basis of outbreak data, the main hazard in these eggs was identified as Salmonella. Salmonellae may occasionally be present on shell eggs even after washing, and any Salmonella reaching the membranes can be transferred to an egg mixture through breaking, and will rapidly grow under improper storage conditions. A Relative Risk analysis showed that cracked eggs are 3 to 93 times more likely than uncracked shell eggs to cause outbreaks. A probability of illness of 1 in 3800 was derived from the 40 million cracked eggs produced in Canada and not pasteurized and the probable 10,500 illnesses arising from these. This was for the general population, but this would be greater for those who consume many shell eggs or would do so in an unsafe manner, or are more likely to be infected (5% of consumers who eat raw or lightly cooked eggs daily, rural communities with more opportunities for obtaining cracked eggs, and those who are immunocompromised and in institutions). Even though it is not possible to precisely determine the risk of salmonellosis through cracked eggs, this assessment indicated that there was enough of a concern that a management strategy was needed. Eight options for managing the risk were considered and ranked for acceptability by both HC and AAFC. Ideally, all cracked eggs should be broken and pasteurized, but this is impractical in certain regions of the country, and other options, such as sales to food processors operating under Good Manufacturing Practices (GMP), and at the farm gate in marked cartons and under controlled conditions, were considered to be acceptable, whereas sales to institutions and bakeries were not. This is the first fromal food-related microbiological risk assessment that HC has completed. Although this is a Canadian problem, any country producing eggs has to recognise that despite any regulations controlling the use of cracked eggs, economics will dictate that some of these will be consumed as whole eggs or egg products, and a management plan is desirable to limit hazardous practices associated with these eggs.