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| Agenda Item 5.2 | Conference Room Document 8 English only |
second fao/who global forum of food safety regulators
Bangkok, Thailand, 12-14 October 2004
Prepared by Dr Scott Crerar, Dr Mark Salter (Food Standards Australia New Zealand)
and Mr Martyn Kirk (Australian Department of Health and Ageing)
In recent times, food regulatory agencies worldwide have been confronted with a need to develop risk management strategies for a number of emerging chemical and microbiological food safety issues. Sharing information from national and international monitoring and surveillance activities has played an important role in bringing these issues to food regulators. In Australia, Food Standards Australia New Zealand (FSANZ) is the body responsible for establishing national food standards and, in collaboration with State and Territory Health agencies, coordinating the risk management response to food safety emergencies and incidents.
The nature of the global environment means that food safety issues are recognised simultaneously in many different countries. Moreover, if an affected product is imported, early detection and effective identification and tracing of the specific source will require communication and liaison with overseas exporting countries. This is often difficult, as the correct links to the appropriate agencies are not well established. By proactively sharing information on contaminant and disease outbreak incidents, authorities may allow other countries to detect and respond to issues quicker and more effectively. The International Food Safety Authorities Network (INFOSAN) and Food Safety Emergency Network is a recent initiative of the World Health Organization that will facilitate information exchange and may enhance the control of international food safety incidents.
The risk management decisions that particular national regulatory agencies may implement in response to similar contaminant incidents will often differ. In some cases this may be because there are equivocal health effects and the risk management strategies are conservative in nature. It may be necessary for regulatory agencies to take conservative approaches based on public or other imperatives. It is important, however, that the reasons for the differences are known, understood and shared so that consumers and other regulatory agencies and trading partners can be informed of and understand the rationale. By sharing risk management approaches and their rationale (including risk assessment) amongst regulatory agencies, countries may be able to learn from each other, thereby facilitating international science-based decision-making and capacity building.
This paper outlines some recent chemical and microbiological contamination issues that have been managed within Australia to draw out lessons and benefits in relation to timely surveillance information and international cooperation and information sharing.
The United Kingdom (UK) Food Standards Agency conducted a survey of soy and oyster sauces in 2001, which found high levels of 3-chloro-1,2-propanediol (3-MCPD) in some products. International notification by the UK of this issue and the associated test result data, combined with Australian dietary exposure information, were initially used by FSANZ to initiate a preliminary food safety risk assessment and formulate an initial response. Subsequently, an analytical survey of soy and oyster sauces available at Australian retail outlets was conducted to more accurately ascertain the levels of chloropropanols and assess their risk in the Australian food supply.
The Australian risk assessment indicated sauces containing greater than 3.5 mg/kg represented an appreciable long-term public health risk for toxicity. To minimise disruption to the food supply, only those products with levels exceeding 3.5 mg/kg of chloropropanols were removed from sale to the public by requesting importers to recall affected products. Subsequently, limits of 0.2 mg/kg for 3-MCPD and 0.005 mg/kg for 1,3-DCP were established by FSANZ in the Australia New Zealand Food Standards Code. The latter also took into account advice from industry as to the lowest levels that could reasonably be achieved. Recent testing of soy and oyster sauces imported into Australia has shown that the majority of manufacturers comply with these limits. Using international data was critical in developing the initial risk assessment and management advice.
In 2002, overseas food agency reports indicated that very low levels of a nitrofuran (furazolidone metabolite) had been found in certain imported prawns and honey. Where residues were detected, they were only at a few parts per billion (μg/kg). However, in the absence of a specific maximum residue level (MRL) in the Food Standards Code, these residues were not permitted in food sold in Australia.
FSANZ undertook a risk assessment to help inform enforcement agencies (State and Territory health agencies and the Australian Quarantine and Inspection Service) on the risk management actions that should be taken to protect consumers, such as testing of or recalling products containing detectable residues. The dietary exposure assessment component of the risk assessment used the residue concentrations found in an Australian industry survey and the hazard identification and characterization was based on a re-evaluation of the data summarized in the Joint Expert Committee on Food Additives monographs.
The assessment indicated very low risks from these trace residues in prawns and honey and that the products were safe to eat. It was not considered necessary, on public health grounds, to recall prawns and honey that were imported into Australia. Upon obtaining further test results on products within the Australian market, testing of prawns and honey was implemented at a rate of 10% of shipments entering Australia, commensurate with the low level of food safety risk to the consumer.
In recent years a number of disease outbreaks have been detected and investigated in Australia associated with imported sesame seed-based products. The importance of international alerts, information exchange and surveillance systems have been critical during the course of these and other investigations. For example, in 2001 a reported outbreak of S. Typhimurium definitive type 104 due to contaminated helva was detected in Sweden. As a result of receiving an international alert on this outbreak an Australian outbreak was subsequently linked to the same product. Subsequent outbreaks associated with contaminated tahini, a paste made from crushed sesame seeds, were seen in Australia. One of these outbreaks, which commenced in November 2002, in New South Wales, Australia, was detected through routine surveillance of human salmonellosis. S. Montevideo was detected in hummus at an implicated retail outlet. The source of the S. Montevideo was traced to imported tahini. Information on the recall of the implicated batches of imported tahini was sent as an international alert via Promed and FSNet.
In 2003 further outbreaks of S. Montevideo were detected in Victoria, Australia, and Auckland, New Zealand. In each of these investigations there were corresponding public recalls of affected products. S. Montevideo was subsequently detected in other sesame seed-based products in Australia and New Zealand, leading to further product recalls.
Summaries of the food testing findings and resultant food recalls from the Australian tahini investigations were posted on Promed and FSNet and Eurosurveillance Weekly. As a result of these alerts, laboratory surveys for microbiological assessment of tahini were undertaken in the UK and Canada, resulting in product recalls and withdrawals.
The recent Salmonella outbreaks associated with sesame seed-based products have been used to refine public health risk assessments in Australia. As a result, sesame-based products are now considered to pose a high public health risk for Salmonellosis and are the subject of more frequent testing for Salmonella both at the domestic and import level.
Between 2002 and 2004 several norovirus outbreaks occurred in Australia that were linked to the consumption of imported frozen oysters. The outbreaks resulted from consumption of both raw and cooked product. The outbreaks in Australia led to recalls and withdrawals of product from the market in several States and Territories.
OzFoodNet—Australia's system for enhanced surveillance of food borne disease—coordinated the investigation of these multiple outbreaks that led to the early recognition of their common food source. However, as several brands of product were implicated, it was necessary for FSANZ to determine from the exporting country whether all of the imported products were sourced from a common harvesting area. This communication established that the products from three of these outbreaks were all sourced from a common oyster harvest area over a similar time period. This information was important for considering the approach used to regulate these products at the Australian border. This information gathering exercise was extremely successful and was facilitated through Australia's diplomatic posts in the exporting country. Very good cooperation was also gained from the exporting country's regulatory authorities and industry. On other occasions dealing with different issues, this type of information gathering has not been as successful and it would be useful to establish complementary information sharing networks amongst countries to allow rapid information exchange between food regulatory agencies in the event of food safety emergencies and incidents.
Further building of communication networks and links to improve this should be encouraged.