MYCOTOXIN RESEARCH AT ESR

1. MYCOTOXIN RESEARCH AT ESR Peter Cressey Institute of Environmental Science and Research November 2010

2. Geography and Mycotoxins – New Zealand and Australia TROPICAL SUB-TROPICAL TEMPERATE

3. Imports of Some Potentially Mycotoxin-containing Foods (ex-FBS 2003)

4. Background - Mycotoxins • Toxic secondary metabolites of fungi, particular species of Fusarium and Aspergillus • Major mycotoxins of concern internationally include; aflatoxins, ochratoxins, trichothecenes (T-2, HT-2, nivalenol, deoxynivalenol), fumonisins, zearalenone, ergot alkaloids, patulin • Most important host plant species are cereals and seeds/nuts (except for patulin –apples)

5. Mycotoxins reported in domestically-grown food

6. The Food Regulatory System in New Zealand and Australia JOINT FOOD STANDARDS

7. The Food Regulatory System in New Zealand and Australia IMPLEMENTATION AND ENFORCEMENT AUSTRALIAN STATES AND TERRITORIES

8. Previous Food Standards - Mycotoxins (Australian) Food Standards Code • Aflatoxin – 0.015 mg/kg in peanuts and peanut products, 0.005 mg/kg in all other foods • Ergot – Not detectable in 2.25 litre of grain • Phomopsin – 0.005 mg/kg in any food New Zealand Food Regulations • Aflatoxin – 0.015 mg/kg in peanuts (shelled) and peanut products, 0.005 mg/kg in all other foods

9. Joint Food Standards - Mycotoxins • Aflatoxins • Peanuts and peanut products 0.015 mg/kg • Tree nuts and tree nut products 0.015 mg/kg • Phomopsins • Lupin seeds 0.005 mg/kg • Ergot • Cereal grains 500 mg/kg Guiding Principle: “MPCs will be established for primary commodities which provide, or may potentially provide, a significant contribution to the total dietary contaminant intake”

10. Mycotoxin Standards - Rationale • Aflatoxins – potent mutagens/carcinogens, peanuts/nuts major source of exposure – ALARA • Phomopsins – (rodent) liver toxin/carcinogen, lupins only recognised source – ALARA • Ergot – highly toxic at high exposure, but generally controlled by modern agriculture and processing. Concerns appear to relate to importation of rye from the Northern Hemisphere Phomopsins and ergot were regulated in the previous Australian standards, but not the previous New Zealand Regulations

11. Mycotoxins for which no Standard was set • Ochratoxins – “insufficient data available to establish whether there is a risk to public health” • Fusarium toxins – “further survey work is now being conducted……risk assessment on these toxins therefore will be finalised when this data become available” • Patulin was not considered

12. Other Mycotoxin Activity – New Zealand • Older surveys on aflatoxins (1977, 1991, 1999, 2000), ochratoxins (2000), trichothecenes (1989-2002), zearalenone (1986-1996), patulin (1981, 1998) • Aflatoxin M1 is included in the annual dairy residue survey • 2005/2006 – Risk profiling of mycotoxins in New Zealand food supply – the current state of knowledge • Identified priority data gaps

13. Industry Focus • Both countries moving to a system where the food producer/processor/importer/retailer is responsible for identifying and managing risks associated with food • Food Control Programmes/Food Safety Programmes will be audited to determine compliance • Some evidence for this happening for mycotoxins in some industries (ENZA – patulin, PCA – aflatoxins)

14. Mycotoxin Research at ESR • Detection/Measurement • Risk assessment/risk prioritisation • (Influence of processing)

15. Measurement of Mycotoxins at ESR Focus on: • Aflatoxins. Regulatory and research. Immunological methods → HPLC → LC-MS/MS/MS • Ochratoxin A. Research. HPLC • Patulin. Research. HPLC • Deoxynivalenol. Research. HPLC Intention to move to multi-mycotoxin LC-MS/MS/MS methods

16. Mycotoxin Activity – New Zealand • Older surveys on aflatoxins (1977, 1991, 1999, 2000), ochratoxins (2000), trichothecenes (1989-2002), zearalenone (1986-1996), patulin (1981, 1998) • Aflatoxin M1 is included in the annual dairy residue survey • 2005/2006 – Risk profiling of mycotoxins in New Zealand food supply – the current state of knowledge • Identified priority data gaps

17. Mycotoxin Risk Ranking or ‘What can I do without data?’ • The risk profiling exercise carried out in 2005-2006 sought to prioritise mycotoxins for further action on the basis of risk • However, in many cases little information was available to generate New Zealand-specific risk estimates • So, how can be make quanitative decisions with quantitative data?

18. Risk Assessment • Hazard Identification (toxicology, epidemiology) • Hazard Characterisation (toxicology, epidemiology) • Exposure Assessment • Risk Characterisation

19. Hazard Identification (Strength of Evidence)

20. Hazard Characterisation

21. Foods Typically Contributing to Dietary Exposure

22. Dietary Exposure Assessment • Little information available on mycotoxin exposure in New Zealand • Available estimates based on fragmentary data • But, some good estimates available from comparable countries (i.e. temperate climate, nett grain importers) • Can use these data to estimate limits on dietary exposure

23. Risk Characterization – Lower Limit

24. Risk Characterisation – Upper Limit

25. Risk Ranking (Qualitative)

26. How do we make Risk Decisions in the Absence of Data? Safety Limit - PTWI What is the level of population exposure? Exposure

27. Exposure/Risk Assessment Refinement

28. Ochratoxin A (OTA) in New Zealand • In 2005, few New Zealand specific data available • Plentiful data from climatically similar areas (Europe) • Also a range of safety limits defined for OTA • Used data to define best and worst case estimates for OTA exposure in New Zealand

29. OTA – Screening Exposure Assessment

30. OTA Screening Exposure Assessment • Worst case estimates indicate potential for New Zealanders to exceeding the safety limit (PTWI) for OTA • OTA became a priority for further action in New Zealand • Involved identification of priority foods and design of surveys to determine the OTA content of foods

31. OTA prevalence

32. New Zealand – Ochratoxin A Concentrations in Selected Foods

33. New Zealand – OTA Exposure • Initial calculation of chronic exposure based on: • Concentration data from 2007 and 2009 surveys • Consumption data from simulated diets (bread, cereals and coffee), nutrition surveys (dried fruit) and import data (spices) • Estimated exposure for adult male – 2.7 ng/kg bw/day (19 ng/kg bw/week) • Equates to 17% of PTWI (JECFA – 112 ng/kg bw/week) • Doesn’t consider extreme consumers or children

34. Aflatoxins – What Foods are Important in New Zealand? Foods of concern are those that are commonly eaten and/or commonly contaminated with aflatoxins and/or may contain very high concentrations of aflatoxins • Corn/maize (2008) • Peanuts and peanut products (2010) • Tree nuts and tree nut products (2010) • Dried fruit (2009) • Spices (2009)

35. Aflatoxin (total) prevalence

36. New Zealand – Aflatoxin Concentrations in Selected Foods

37. What Does this Mean with Regards to Risk • Aflatoxins are present in a number of foods consumed by New Zealanders • Differing prevalence and concentrations • Some foods more commonly eaten than others • Some foods eaten in larger portions than others Dietary exposure assessment allows integration of all these factors – are currently carrying out dietary exposure assessment for aflatoxins

38. Influence of Food Processing The normal processing of crops to produce foods eaten by humans can have a significant impact on the mycotoxin content e.g. • Roasting of peanuts can reduce the aflatoxin content by 50-80% • Wet milling of maize reduces aflatoxin levels to less than 1% of the levels in the raw grain • Cleaning of wheat removes 44% of OTA contamination • Breadmaking reduces DON levels by up to 60%

39. Influence of Food Processes – OTA in breadbaking