6th National Abalone ConventionThe Tale of Marine Biotoxins in Abalone

Cathy Webb & Alison TurnbullSeafood NZ & SARDI6-8th August 2014 Queenstown NZ

FEARLESS HERO IN QUEST OF THE TRUTH

CRUSADING KNIGHTS OF THE TOXIN TABLE

The Tale of Marine Biotoxins in Abalone

DAMSELS IN DISTRESS

What are marine biotoxins?• Produced by marine micro-algae, can contaminate seafood and cause

illness when consumed. Syndrome Causative toxins SymptomsParalytic Shellfish poisoning (PSP)

Saxitoxin group (STX) neurological symptoms; tingling sensations in extremities, headaches, dizziness, nausea, muscle/limb paralysis respiratory distress and in extreme cases death

Diarhhetic Shellfish Poisoning (DSP)

OA group toxins: okadaic Acid (OA), dinophysistoxins (DTX) and derivatives

diarrhoea, nausea, vomiting and abdominal pain

Amnesic Shellfish Poisoning (ASP)

Domoic acid and isomers (DA) Symptoms involving multiple organ systems; gastrointestinal tract, central nervous system and the cardiovascular system. In severe cases death may ensue, or neuronal damage can persist for years after exposure to the toxin.

Neurotoxic Shellfish Poisoning (NSP)

Brevetoxin group (BTX) Acute neurological and gastrointestinal effects (e.g. nausea, diarrhoea, numbness, temperature reversal, slurred speech, respiratory distress, seizures

Alexandrium speciesGymnodinium catenatumDinophysis speciesPseudo-nitzschia speciesKarenia species

Image - A.Vaquer

Image D. Thomas

NZ Production• Average of 965 tonne of wild caught paua (H. iris and H. australis)

predominantly H. iris, harvested per year• Annual volume of aquaculture product is approx 105 tonnes which is

primarily exported as whole frozen• Wild caught paua are processed and exported in a number of different

forms – Live– Frozen – Chilled;– Cans or jars: – Smoked/Dried/Salted/Brined

Australian Production• Average of 4642 tonne of wild caught abalone (H. rubra, H. laevigata,

H. roei) predominantly H. rubra, harvested per year• Annual volume of aquaculture product is approx 600 tonnes • Abalone are processed and exported in a number of different forms

– Live, fresh, chilled– Preserved (including canned)– Frozen meat– Frozen (whole, shell on)– Par boiled– Dried – Other

Product Type by Weight – All Export Markets

Cans/Jars28%

Dried0%

Frozen10%

Live, fresh, chilled

51%

Par boiled

1% Other10%

Australia

Cans/Jars89%

Smoked/ Dried/ Salted

5%

Frozen4%

Live1% Chilled

1%

New Zealand

Export Markets

Singapore

11%

Hong Kong54%

Malaysia1%

China17%

USA1%

Japan12%

Other4% Australia

Singapore

43%

Hong Kong40%

Malaysia6%

China1%

USA1%

Australia6%

Other3% New Zealand

International Marine Biotoxin Standards

MarketSpecies to which ML

applies

PST

(Saxitoxin group)

DST

(Okadaic Acid Group)

AST (DomoicAcid)

NST (Brevetoxins)

China Aquatic products 0.8 mg/kg 0.6 mg/kg N/A N/A

Japan Shellfish4 MU (i.e. 0.8mg/kg)

0.05 MU N/A N/A

USA* All fish 0.8 mg/kg N/A 20 mg/kg N/A

EU (France

UK)

Molluscs, live echinoderms, tunicates and marine gastropods

(including abalone)

0.8 mg/kg 0.16 mg/kg 20 mg/kg N/A

Early PST discoveries in abalone

• 1991 Spain low levels detected in abalone foot and viscera• 1994 Japan detected in Spanish imported abalone

– Further testing showed >23 x the bivalve reg level in foot, >3 x bivalve reg level in viscera

– No source detected

• 1998 Australia (Vic) PST detected at 1.5 x bivalve regulatory level in abalone viscera, just below reg level in foot

• 1999 South Africa: 20 x bivalve reg level, highest in foot• South Africa currently monitoring abalone farms for PSTs

every 2 weeks, DSTs & ASTs every month

EU Trade restrictions in Australia

• Pre-2007 small amounts Australian abalone exported to EU (~$7 million/annum)

• 2007 Australian abalone exports to EU ceased– ‘Must classify abalone production areas’ (European

Commission)• 85% Australian wild abalone harvest taken from areas where

no biotoxin monitoring is in place• “a national monitoring program would require infrastructure

investment of AUD$4-5 million and an estimated annual cost to the industry of approximately AUD$20m” David Hudson SGA Solutions

EU Trade restrictions in Australia

• Pre-2007 small amounts Australian abalone exported to EU (~$7 million/annum)

• 2007 Australian abalone exports to EU ceased– ‘Must classify abalone production areas’ (European

Commission)• 85% Australian wild abalone harvest taken from areas where

no biotoxin monitoring is in place• “a national monitoring program would require infrastructure

investment of AUD$4-5 million and an estimated annual cost to the industry of approximately AUD$20m” David Hudson SGA Solutions

Aussie response

• independent, robust, defensible scientific advice

What is ?• Technical platform

• Australian Seafood CRC funding

The purpose of SafeFish is to:

• provide technical/scientific expertise to enable rapid response to sustain free and fair access to key markets, and

• underpin the safety and hygiene of seafood sold commercially in Australia

Who is ?• Partnership of Seafood Safety & Market Access

Experts– Food Standards Australia New Zealand– Department of Agriculture– Industry (Seafood Trade Advisory Group, Australian

Shellfish Quality Assurance Advisory Committee, SeafoodTrade Advisory Group, Sydney Fish Markets, NationalSeafood Industry Council, Seafood New Zealand -observer)

– Funding bodies (Australian Seafood CRC, FisheriesResearch and Development Corporation)

• Industry and Expert panels to provide advice

What Does Do?

• SafeFish provides scientific support to solve issues and challenges relating to the export, import and domestic trade of seafood products.

• Develops technical/scientific advice for trade negotiations

• Develops technical briefs on high priority Codex issues• Facilitates technical attendance at high priority Codex

meetings and specific working groups• Identifies emerging market access issues• Facilitates research into priority issues

Initial risk assessment –PST in canned product

Initial risk assessment – PST in canned product

• Low propensity for abalone to take up PST• Commercial canning processes significantly reduce levels• Negligible risk of illness to consumers

Information package put together for trade negotiations

• In July 2010 the EU revised legislation – abalone no longer subject to growing area classification requirements

• Research allowed Australia to argue against draft Codex standard with mandatory biotoxin testing

The NZ Situation• In 2007 the EU did not introduce trade restrictions for NZ Paua • Reasons: NZ Marine Biotoxin Controls included Paua

– In 1999 MAF (now MPI) issued Technical Directive (TD 99/125), stating

“Paua that are harvested from a growing area which is closed to the harvesting of shellfish, shall be shucked or degutted before packing for export purposes”

• Even so, NZ was still exposed as not all paua harvesting areas are subject to monitoring either through the Commercial Shellfish Programme or the Non-Commercial Programme

The Proposed Standard • In 2006, the Codex Committee of Fish and Fishery Products

(CCFFP) agreed to new work to develop a standard for abalone• The first draft was presented to CCFFP in 2007 and included the

following requirements:– Abalone harvesting areas or farms to be approved by the official agency– Limits for Marine Biotoxins, and associated monitoring programmes.– Microbiological monitoring programmes for growing/harvesting areas – Microbiological limits for both E.coli and Salmonella

• The Standard was not accepted and sent back for re-drafting• The Standard was further discussed at several CCFFP meetings

over the following years and agreed to 2012, published in 2013

The Published Standard The Standard for Live Abalone and for Raw Fresh Chilled or Frozen Abalonefor Direct Consumption or for Further Processing (CODEX STAN – 312-2013), now contains the following:

• “Abalone from some geographical areas have been found to accumulate certainmarine biotoxins. It is up to the Competent Authority (using a Risk Assessment) todetermine whether a risk exists in any geographical areas under its control and if so,put in necessary mechanisms to ensure that the part of the abalone to beconsumed, meets with the marine biotoxin level in the Standard for Live and RawBivalve Molluscs (CODEX STAN292-2008).

• The Risk Assessments should be undertaken in accordance with the WorkingPrinciples for Risk Analysis for food Safety for Application by Governments (CAC/GL62-2007).”

Where did that leave NZ?• In NZ we had results from various sampling of paua

dating back to 1993

• These indicated the risk was low but we did not havea scientifically valid Risk Assessment that would standup to international scrutiny

• NZ PIC funded Brenda Hay to conduct an independentreview of the current situation

• This found there was evidence, even though it waslimited, of the potential for paua to accumulatemarine biotoxin toxins

• This meant that we needed to conduct a full riskassessment that had creditability

Partnership approach

• Uptake and elimination rates

• Event monitoring

Risk assessments

Novel toxin• Deoxydecarbomyl saxitoxin in high levels in Tas abalone –

closed highly productive zones (8% Australian fishery)• Precautionary approach by regulators• Purified and characterised by Cawthron• Very low potentcy - TEF 0.042

PST toxin project - Outcomes

• Standard solution produced for future quantification

• Reduced closures in future

PST toxin project - outcomes

• Confirmation of microalgae as source of PST toxins- world first – can now monitor for the alga rather than the toxin– Use information available on seasonality, bloom conditions,

longevity of blooms etc– Potential to combine monitoring with other fisheries

• PST uptake and depuration kineticsmussels >> abalone viscera >> abalone foot

– Can use mussels as sentinel species during bloom initiation but not during bloom decline

• Draft biotoxin monitoring options produced and costed

Joint risk assessmentsAims:• Reduce technical barriers to trade

in key markets such as China, Japan and the EU. This will be delivered by using the risk assessment output of the project to negotiate risk based international biotoxinstandards (at Codex)

• Enhance R&D capability on marine biotoxins and market access in Australia

Joint risk assessmentsAims:• Reduce technical barriers to trade

in key markets such as China, Japan and the EU. This will be delivered by using the risk assessment output of the project to negotiate risk based international biotoxinstandards (at Codex)

• Enhance R&D capability on marine biotoxins and market access in Australia

Funders• Abalone Council of Australia• Paua Industry Council (NZ)• Australian Seafood Cooperative Research Centre• Fisheries Research and Development Corporation• Department of Further Education, Employment, Science and

Technology, South Australia• Marine Innovation South Australia• NZ Ministry for Primary Industries (formally NZFSA)

The swiss cheese statementSeveral conditions must all be met for abalone consumers to be at risk from shellfish poisoning:

• high levels of the toxin must be present in the harvest area at or just prior to harvest

• abalone must be able to accumulate significant amounts of this toxin in the edible tissues

• Consumers eat enough abalone to exceed the acute reference dose for that toxin by a margin significant enough to cause illness.

The absence of any confirmed or probable cases or outbreaks of shellfish poisoning linked to the consumption of abalone indicates that these conditions are rarely all met.

Toxins in Aussie abalone

Prevalence Survey• 190 abalone from 68 fishing blocks over 16 months• No sample > bivalve regulatory levels for PST, AST, DST

<1.6% abalone contaminated with marine biotoxins above regulatory levels

• ASTs detected in the foot and viscera in very low levels• PSTs were also detected at very low levels in 17 samples of

abalone foot tissue and 6 samples of abalone viscera.NRS survey of 51 abalone 2002-2004 – no toxins detectedEvent monitoring; PST > reg levels in viscera

Toxins in NZ paua

• More long term monitoring data through non-commercial marine biotoxin programme

• Event monitoring – PSTs and DSTs– 452 samples tested for PST in

abalone since 1993– 419 DST samples– 314 AST samples

• All below bivalve reg levels except one DST viscera sample

The swiss cheese statementhigh levels of the toxin must be present in

the harvest area at or just prior to harvestabalone must be able to accumulate

significant amounts of this toxin in the edible tissues

Consumers eat enough abalone to exceed the acute reference dose for that toxin by a margin significant enough to cause illness.

The absence of any confirmed or probable cases or outbreaks of shellfish poisoning linked to the consumption of abalone indicates that these conditions are rarely all met.

NZ risk assessment resultsProduct Toxic Syndrome Risk

NZ paua viscera in neutraceutical products

PSP Extremely low

NZ paua viscera in neutraceutical products

DSP Extremely low

NZ paua meals (foot only) PSP Extremely low

NZ paua meals (foot only) DSP Extremely low

NZ paua meals (foot & viscera) PSP Low

NZ paua meals (foot & viscera) DSP Low

NZ whole paua ASP Low

NZ whole paua NSP Low

Australian risk assessment resultsProduct Toxic Syndrome Risk

Processed Australian abalone (e.g. canned, dried and frozen

meat)

PSP Extremely low

Unprocessed Australian abalone food products

PSP Low

Whole steamed/boiled Australian abalone or abalone

with viscera puree

PSP Low

Australian abalone viscera sashimi

PSP Low-moderate

Whole Australian abalone DSP Low

Whole Australian abalone ASP Low

Whole Australian abalone NSP Unknown

Knowledge gaps• PST levels in abalone following Alexandrium sp. blooms• Why are observations of PST in paua different?• The occurrence of marine biotoxins in some areas in Australia and

New Zealand from which large volumes of abalone are harvested e.g. the western coast of Tasmania, Fiordland, Chatham Islands

• Prevalence of some toxins in NZ paua • Impact of processsing • Significant data gaps on abalone consumption;

– meal types consumed – sizes

• Propensity of abalone and paua species to accumulate and retain toxins during some toxin-producing phytoplankton blooms.

Outcomes -Direct benefits for industry• International acceptance of risk based Codex standard• Demonstration of the low risk for NZ and AU

commercially harvested wild abalone

Protection of market access

• Avoidance of mandatory large scale biotoxinmonitoring (AU $20mill + NZ $2-3 mill p/a)

Outcomes -Direct benefits for industry• Standard available for quantification of novel congener• Determination of source of PST, uptake and elimination

rates, potential sentinel species• Knowledge to underpin management and future

incident response• Knowledge of future areas of research need for

improved risk management

Outcomes -Indirect benefits for industry

• Partnerships created• Increased capabililty for analysis and research

– Analytical laboratory in Australia– Research strength in biotoxins at SARDI– Added to Cawthron research strengths– Research partnerships between Kiwis and Aussies

• Increased capability in TMA arena– Networks of industry, governments, researchers– SafeFish

Where to from here?

• We need improved consumption data for both countries in the major markets

• Better understanding of toxin uptake in abalone – across toxin groups, all commercial abalone species– Bloom events OR – Rolling prevalence survey

Cast - IndustryMark Webster, Wayne Haggar, Dean Lisson, Chris Madson, Alex Ziolowski, Duncan Worthington Cathy Webb, Storm Stanley, Jeremy Cooper, Mark Janis, the NZ paua industry samplers

Cath McLeod, Alison Turnbull, Natalie Dowsett, Navreet Malhi, Jessica Tan, Andreas Kiermeier, Amanpreet Sehmbi (SARDI)Brenda Hay (Aquabio Consultants)Tim Harwood, Craig Waugh, Andy Selwood, Kirsty Smith (Cawthron)Shauna Murray (SIMS)Gustaaf Hallegraeff (Utas)Laura Smith, Sam Ibbott, Ruth Eriksen (Marine Solutions)Sue Dobson

Researchers

Cast - OthersJim Sim, the late Phil Busby, Brian Roughan (MPI)Lynda Hayden (Dep Ag)Judy Cunningham and Rosalind Dalefield (FSANZ)Rosalind Harrison (DHSS Tasmania)Debra Gradie and Katrina Knope (OzFoodNet)Anthony Zammitt, Andrew Clarke, Howel Williams, Megan Burgoyne, Clinton Wilkinson (Shellfish Quality Assurance Program Managers and staff)Janet Howieson and Rowan Kleindienst (Curtin University)Jayne Little (PIRSA Mapping)Stephen Mayfield, Andrew Hogg, Paul van Ruth, Marty Deveney, Darren Fisher, Xiaoxu Li, and Damian Matthews (SARDI) David Tarbath (Institute of Marine and Antarctic Studies, University of Tasmania) John Foord (Department of Agriculture, Forestry & Fisheries, South Africa)Dorothy-Jean McCoubrey (Dorothy-Jean & Associates Ltd)

For more information please visit:

www.safefish.com.au