Dar seafood ppp standard

Low relative risk rankings

A significant number of seafood commodities were ranked as presenting a low relative risk to the general population. For some of these, limited consumption of the product was the main factor that led to the conclusion that adverse health effects from associated hazards was unlikely. For others, the probable effect of downstream processing and consumer handling on hazard levels was a factor in reducing that likelihood.

5. Uncertainty and variability

The relative risk rankings outlined in this document will inform FSANZ’s consideration of risk management options. Consequently, it is important to recognise and consider the areas of uncertainty and variability in the ranking. While the rankings are underpinned by available epidemiological data, hazard identification, risk characterisation and detailed evaluations of the seafood supply chain, they remain largely qualitative.

Uncertainties in the risk rankings primarily come from significant data gaps in the information used to derive the ‘likelihood of illness’ rating. The available surveillance and epidemiological data demonstrating the association between hazards, seafood commodities and food-borne illness are recognised as being limited. Estimates of the amount of food-borne illness due to seafood are therefore wide-ranging, depending upon the assumptions used, and vary from around 4% to up to 25% of the total burden of food-borne illness in developed countries [65-67]. In addition, the gaps in data and information are unevenly spread across hazards and commodities, necessitating employment of a degree of expert opinion/judgement in the likelihood of illness ratings, to bridge the gap between what is indicated by the data and what is plausible given our knowledge of the hazard, the seafood commodity, its regulatory environment, and its production and processing supply chain up to the point of consumption. This has militated against completion of a formal quantitative exposure assessment for each hazard/commodity pairing considered. Qualitative estimates of the likelihood of illness due to the presence of a particular hazard in a seafood commodity were derived, based on available information.
The seafood consumption figures were derived using data from the 1995 National Nutrition Survey of Australia, which was based on selected consumers’ recollection of the food they had consumed over a designated 24-hour period. This tends to lead to an over-estimation of habitual food consumption amounts for high consumers and for foods that are only occasionally eaten. Other limitations of the National Nutrition Survey data are that smoked finfish was not identified as being hot- or cold-smoked, or as ready-to-eat or raw (for example, smoked cod); and scallops were not identified as being roe-off or not.
Further uncertainty in the risk rankings arises from the evolving regulatory and non-regulatory risk management environment for seafood in Australia. The impact of such changes on the safety of seafood can only be judged over the course of a number of years, when it might be reflected in the epidemiological, prevalence and concentration data used in generating the risk estimates.
Variability in the risk posed by seafood products can arise from a number of factors, including geographical factors contributing to the risk (for example, risk of ciguatera poisoning is relative to levels of consumption of larger reef fish; risk due to Salmonella in cooked prawns is influenced by the method of production – wild-catch versus aquaculture).
Application of international data to the Australian situation may also be a source of variability in risk estimates. For example, differences in the virulence of pathogens, the susceptibility of populations or the levels of hazards in seafood can all affect the overall level of food-borne illness arising from a particular product/hazard combination. However, international data was used in the analysis, particularly in cases where Australian data was lacking or where a significant amount of the seafood commodity was imported.
As significant data gaps are gradually filled by the results of ongoing research and scientific evaluation, the robustness of the risk rankings can be better assessed and the rankings may be further refined. As it stands, the rankings place seafood industry sectors into broad relative risk categories as a basis for considering appropriate risk management strategies.

6. Conclusions

The relative risk rankings described in this report demonstrate that, under current risk management practices – both voluntary and mandatory – in Australia, public health and safety risks are low for the majority of seafoods. A small number of industry sectors present a higher public health risk relative to other seafoods.

The report concludes that the following seafood sectors are ranked in the high relative risk category:

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  oysters and other bivalve molluscs (except when the consumed product is only the adductor muscle, for example, roe-off scallops) harvested from growing environments likely to be exposed to faecal contamination and/or not under a shellfish safety management scheme
  
• 
  ready-to-eat cold-smoked finfish (and other ready-to-eat cold-smoked seafood products) when eaten by population sub-groups susceptible to invasive Listeriosis.
  
  
  

Oysters and other bivalves have been the food vehicle in several large and small outbreaks of food-borne illness in Australia over the past 15 years. The food safety hazards involved have included enteric viruses, algal biotoxins and pathogenic bacteria. When harvested from waters managed by a comprehensive shellfish safety scheme, such as the ASQAP, oysters and other bivalves were ranked in the medium relative risk category.
Cold-smoked seafoods have been linked to outbreaks of listeriosis overseas, but there has been no such epidemiological linkage established in Australia. However, there are several factors that might lead to an underestimation of the linkage.
Listeriosis is primarily a sporadic disease affecting susceptible populations (the foetus, pregnant women, neonates, the elderly and the immunocompromised) and, although it can infect healthy people, the low rate of infection in the general population probably means some outbreaks go undetected [58].
The inherent difficulties in determining the food vehicle, due to the long incubation time of the disease, typically militate against identification of the actual food vector.
Of the seafood commodities ranked in the medium relative risk category, prawns and fish (whole or as fillets) have been linked to several outbreaks of food-borne illness in Australia in recent years.

For prawns, the associated food safety hazards have been primarily microbiological hazards, while for fish, ciguatoxin, histamine fish poisoning and escolar wax esters account for the majority of outbreaks.

The conclusions of the risk ranking are subject to uncertainties introduced by significant data gaps and ongoing changes in the risk management environment applying to seafood in Australia. Gaps and uncertainties mean the conclusions must be understood to be based on the current state of knowledge and that they are subject to revision in the light of any new information/data that might become available in the future. So, as the data gaps are filled by the results of ongoing scientific studies and surveys of the prevalence and levels of food safety hazards in seafood in Australia, the rankings may need to be reconsidered and further refined.