Dar seafood ppp standard

Risk ranking method

Food Standards Australia New Zealand (FSANZ) estimated relative public health risks by considering the severity of any adverse health effect resulting from the presence of a particular hazard in a seafood commodity, together with the likelihood of that adverse health effect occurring.

Estimates of the severity of illness due to the presence of hazards in seafood followed an internationally accepted procedure that considers the duration of illness, likelihood of death and potential for ongoing adverse health effects.
Estimates of the likelihood of adverse health effects were based on:

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  the link between the hazard and illness due to consumption of the particular seafood (epidemiological data)
  
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  the prevalence and concentration or level of the hazard in seafood
  
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  patterns of consumption of the specific seafood (frequency of consumption, amount eaten)
  
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  the impact of existing regulatory and non-regulatory risk management systems
  
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  data and information on the following factors related to the properties of the hazard and the effect of production, processing and handling, particularly in terms of how they might influence hazard levels at the point of consumption:
  

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  the capacity for microbiological pathogens to survive or grow in the commodity
  
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  any other relevant properties of the hazard (for example, toxigenic or infectious dose)
  
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  the probable effect of production, processing and handling on the presence and level of the hazard
  
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  the likely effect of consumer handling (including cooking and product shelf life) on hazard levels.
  

Using a ranking matrix, FSANZ combined the severity and likelihood estimates into a broad relative risk estimate for each hazard that might be found in a seafood commodity (for example, prawns) or group of similar commodities (for example, oysters and other bivalve molluscs). An overall relative risk ranking for each commodity (or group of commodities) was then obtained by determining the highest relative risk ranking estimated for the commodity.

Future reviews of the risk ranking

The risk ranking is based on the best current knowledge and data. Such rankings are dynamic, with their evolution reflecting increasing knowledge about the hazards and the consumer’s exposure to them. For example, the introduction of new technologies, modified production practices and changes in management strategies may influence the need to review the rankings.

FSANZ will maintain a watching brief of the scientific literature and international activities, for example, Codex Alimentarius, which may impact on the risk ranking. Where significant data gaps impacting upon the risk ranking process 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 robustness of the risk rankings can be better assessed and the rankings may be further refined.

Food safety hazards in seafood

Seafood can contain food safety hazards derived from several different sources. Some of these hazards occur naturally in the environment in which seafood lives and grows and are unavoidable contaminants of seafood when it is harvested. Others are a consequence of the impact of human activities on the environment.

In the pre-harvest phase of production, feed components, veterinary drugs and other chemicals employed in aquaculture production may also present a public health risk.

In addition to these, food hazards can be introduced into seafood, or caused to increase to potentially hazardous levels, through direct contamination by food handlers and contaminated utensils and equipment and by inadequate handling (for example, temperature abuse, cross-contamination, inadequate processing).

The extent to which any food safety hazard is likely to be present in seafood depends on a number of factors. These factors include the biology of the particular seafood species, its growing environment, and the conditions along its production and processing supply chain. Therefore, the broad biological classes of seafood species (bivalve and cephalopod molluscs, crustacea and finfish), and the public health risks posed by hazards associated with specific commodity groups within those classes, have been considered separately.

Summary of risk rankings

The relative risk rankings described in this report demonstrate the generally high level of safety of seafood products. Under current risk management practices – both voluntary and mandatory – public health risks are relatively low for the majority of seafood. A small number of commodities present a higher public health risk than other seafood.

The report concludes that the following seafood sectors are ranked in the higher 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
  
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  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 bivalve molluscs

Oysters and other bivalve molluscs (except when the consumed product is only the adductor muscle, for example, roe-off scallops) harvested from growing environments vulnerable to faecal contamination and/or not under a shellfish safety management scheme present a relatively high risk to public health, mainly due to the likelihood of illness caused by contamination with hepatitis A virus and algal biotoxins (particularly amnesic shellfish poison and paralytic shellfish poison). These hazards are introduced in the pre-harvest phase of bivalve production.

This relatively high risk ranking is consistent with other studies based on recent epidemiological data that reflected a situation where inconsistent risk management systems were in place across Australia.
Food-borne illness due to oysters and other bivalve molluscs in Australia have resulted in a number of small outbreaks and sporadic cases due to Vibrio species and a few large outbreaks due to enteric viruses in oysters harvested from polluted and inadequately controlled waters.
While adoption of risk management strategies has improved the safety of bivalve shellfish in recent times, some risk remains. Although monitoring of harvest waters for indicators of sewage pollution (for example, faecal or total coliforms) helps to manage the risks due to enteric pathogens, bacterial and viral, it cannot predict levels of Vibrio species and enteric viruses in oysters. Oysters harvested from waters without a risk management system in place have a higher risk of contamination by algal toxins. Therefore, where oysters and bivalves are harvested from waters managed under a comprehensive shellfish safety scheme, such as the Australian Shellfish Quality Assurance Program (ASQAP), the risk is significantly reduced – notably, the likelihood of a food-borne illness is low.
The risk rankings for oysters and other bivalves were the same regardless of whether they were to be cooked or eaten raw, as the hazards leading to the risk rankings are not greatly affected by the light cooking normally applied to these products.

Ready-to-eat cold-smoked seafood

Ready-to-eat cold-smoked finfish (and other ready-to-eat cold-smoked seafood products) present a higher risk to public health relative to other seafoods due to the possibility of contamination with Listeria monocytogenes and the potentially severe illness it causes in at-risk population sub-groups such as pregnant women. L. monocytogenes is a ubiquitous organism often found in processing environments, and may also be present in fish at the time of harvest. Cold smoking is not a listericidal process.

Recognition of the risks by both regulators and the industry has resulted in a high level of management of L. monocytogenes in Australia and a lower risk of illness to the general population.
FSANZ has previously recognised the inherent risk to the general population due to L. monocytogenes in cold-smoked seafoods by including a microbiological limit standard for the organism in ‘ready-to-eat processed finfish, other than fully retorted finfish’ in the Australia New Zealand Food Standards Code. When the food safety risks are managed such that cold-smoked seafoods meet this regulatory requirement, the relative risk ranking for the general population is low, although the relative risk ranking for susceptible populations (for example, pregnant women, neonates, immunocompromised people and the elderly) is high. FSANZ is currently reviewing its dietary advice to these at-risk sub-groups in order to manage their food safety risks due to L. monocytogenes from all food sources.
If the food safety risks are not properly managed, such that cold-smoked seafoods do not meet the microbiological limit standard for L. monocytogenes, the relative risk ranking is high for at-risk sub-groups and medium for the general population. This takes account of the relatively long shelf life of the product and the high standards of hygiene and sanitation in processing and good temperature controls across the food supply chain, up to and including the consumer, that is needed to ensure the safety of the product.

Other seafood commodities

FSANZ ranked other seafood commodities as presenting a low or medium relative public health risk.

The vast majority of whole and filleted finfish was ranked in the low relative risk category. A few groups of fish species were ranked in the medium relative risk category:

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  larger specimens of particular species of tropical and sub-tropical finfish from certain fishing areas, due to the potential for illness as a result of accumulation of ciguatoxins
  
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  large, long living or predatory fish, such as swordfish, shark/flake and some tuna, which tend to accumulate higher levels of methylmercury than other fish species. The ranking applies to the at-risk sub-population (the foetus) when the mother consumes mainly those species.
  
  
  

A medium ranking was also assigned to the following commodity groups (due to the listed hazards):

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  univalve molluscs (for example, abalone) and roe-off scallops (from algal biotoxins causing amnesic shellfish poisoning and paralytic shellfish poisoning)
  
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  prawns (V. cholerae O1, Salmonella Typhi, arsenic)
  
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  canned seafood (Clostridium botulinum)
  
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  hot-smoked fish products (C. botulinum)
  
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  some whole and filleted finfish (arsenic).
  
  
  

In most cases, hazards linked to these medium risk commodities are already regulated in the Food Standards Code (for example, Salmonella in prawns, arsenic in finfish) or through longstanding and effective industry codes of practice (for example, C. botulinum in low-acid canned foods).

Of the seafood commodities ranked in the medium risk category, prawns and some finfish (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 finfish, ciguatoxin, histamine fish poisoning and escolar wax esters account for the great majority of the outbreaks.

The majority of seafood commodities presented a lower risk to the general population. For some of these commodities, limited consumption of the products was the main factor in leading to the conclusion that the likelihood of adverse health effects from associated hazards was very low. For others, the probable effects of downstream processing and consumer handling in reducing hazard levels were factors leading to a low likelihood of illness.