The Environmental Effects of Mycotoxins

1. The Environmental Effects of Mycotoxins UMD – Chemical Ecology TIP 2A

2. The Mycotoxin System

3. The Mycotoxin System • Composed of five interacting systems. • Metabolism + Toxicology + Health +Wealth + Productivity[1].

4. The Spoilage System

5. The Role of Key Words in Spoilage System • Temperature:High-temperature stress is one of the major determining factors in mold infestation and toxin production. • Specific crop growth stages:Specific depths are set for each growth stage, in particular to assist plant establishment • Poor fertility:Mycotoxins are included in the toxic substances that often occur in animal feeds, posing a serious menace to animals ingesting them ; for example acting directly and indirectly on pig fertility. • High crop densities: Has been associated with increased mold growth and toxin production • Weed competition:Increases theincidence rate of mycotoxins

6. Molds and mycotoxins of world-wide importance Mold species Mycotoxins produced Aspergillus parasiticusAflatoxins B1, B2, G1, G2 Aspergillus flavusAflatoxins B1, B2 Fusarium sporotrichioidesT-2 toxin Fusarium graminearumDeoxynivalenol (or nivalenol)Zearalenone Fusarium moniliforme (F. verticillioides) Fumonisin B1 Penicillium verrucosumOchratoxin A Aspergillus ochraceusOchratoxin A Source[2]

7. The co-occurrence of mycotoxins • Adequate time, temperature or humidity controls • Food grade packaging • Potable water supplies • Maintenance of equipment[2]

8. The Socio-Economic System The Food and Agriculture Organization (FAO) estimates that 25% of the world's food crops are affected by mycotoxins, of which the most notorious are aflatoxins. [3] In many developing countries, the combination of insufficient drying and humid atmospheric conditions results in unacceptable levels of aflatoxin in harvested maize, groundnuts, tree nuts and other foods[9] In Africa, fifteen countries, accounting approximately 59 percent of the continent’s population, were known to have specific mycotoxin regulations in 2003 ([9]

9. SocialFactors Concerns about social and ethical values among consumers of organic food include; • Providing assurance that consumer concerns are met • Identification of quality focused critical control points in organic food • Examples of identified critical control points • The organizational and educational requirements for utilizing this concept in real supply chains

10. CulturalFactors Aflatoxins are considered unavoidable contaminants of food and feed, even where good manufacturing practices have been followed. The FDA has established specific guidelines on acceptable levels of aflatoxins in human food and animal feed by establishing action levels that allow for the removal of violative lots from commerce[5] Cultural practices, including crop rotation, tillage, planting date, and management of irrigation and fertilization, have limited effects on infection and subsequent mycotoxin accumulation. Current infrastructure and grain storage practices in developed countries can prevent postharvest development of mycotoxins, but this aspect remains a threat in developing countries, especially in tropical areas[9]

11. Figure 1[5]

12. PoliticalFactors All nations have the right and the duty to protect their citizens from the harmful effects that undesirable substances in food may cause. The impact of an intentional act of mycotoxin contamination could be severe; with potential public health outcomes involving high mortality and devastating economic consequences stemming from the corresponding impact on the healthcare system, public fear, and avoidance of affected products[6]. International enquiries on existing mycotoxin legislation in foodstuffs and animal feedingstuffs have been carried out several times in the 1980s and 1990s and details about tolerances, legal bases, responsible authorities, official protocols of analysis and sampling have been published[3]. Several other factors may influence the establishment of mycotoxin limits and regulations. These include: availability of toxicological data of mycotoxins, availability of exposure data of mycotoxins, knowledge of the distribution of mycotoxin, concentrations within a lot, availability of analytical methods, legislation in other countries with which trade contacts exist, need for sufficient food supply[9]

13. THE CONTROL SYSTEM Identification of steps in the Commodity Flow where mycotoxin contamination is most likely to occur : • Identification of mycotoxin hazard: First consider which, if any, of the mycotoxins known to constitute a food safety hazard are likely to be present. • Possible Mycotoxin Control Measures: The most effective mycotoxin control measures is to dry the commodity such that the water activity (aw) is too low to support mould growth and/or prevent mycotoxin production[3].A control measure is any action and activity that can be used to prevent or eliminate a food safety hazard, or reduce it to an acceptable level. • Determine Critical Control Points (CCPs): Can be achieved using a well designed decision tree, if necessary, to supplement the knowledge and experience of the HACCP team • Establish a monitoring system for each CCP: The monitoring system must be a scheduled measurement, usually of a basic parameter such as temperature or time, to detect any deviation from the critical limits.[3]

14. Effects of Mycotoxin on health and Environment • Aflotoxins are Carcinogenic, teratogenic, immunosuppressive • Synergistic with hepatitis B and C viruses • In India more than 20 million people are carriers[3] of Aflotoxins • Affect health of human beings, cattle, sheep, poultry and ducks[7] • Environmental conditions that favor fungal development in crops and commodities, and lack of regulatory systems for aflatoxin monitoring and control. • In warm, humid developing countries, regular mycotoxin presence in the diet affects human populations and domesticated animals, causing morbidity and premature deaths

15. Mycotoxins and the health of humans and livestock Figure 2[8]

16. Why should we study them • Ubiquitous in many foods, especially consumable food products in developing countries • Three ICRISAT mandate crops are contaminated: groundnut, sorghum and millet. ICRISAT believes in the potential of biotechnology to enhance the speed, precision, efficiency and value addition in many aspects of its crop improvement efforts[10]. • Many commodities used along with our mandate crops in foods and feeds are contaminated. • Mycotoxins and the pathologies they induce are becoming a world-wide preoccupation and a cause of serious economic and sanitary problems. • In Tunisia a clear cut correlation has been found between the consumption of food contaminated by toxigenic fungi and specific pathologies. Clinical and laboratory-based studies performed in our laboratory provide a mechanistic explanation for the toxic effects of some mycotoxins[11]

17. TWO IMPORTANT ISSUES • DIAGNOSIS • Cost-effective tools (immuno-logical, ELISA-based) • Adaptable to developing countries • MANAGEMENT • Contamination can occur at pre-harvest, during harvest and post-harvest storage • Experiments conducted to understand the factors contributing to contamination • Important for international trade

18. Figure 3[8] • Source: Dr. MVLN Raju, Project Directorate on Poultry (ICAR),Rajendranagar 500 030

19. Interactant factorsFigure 4[8]

20. Many factors make the process of mycotoxin prevention hard . On the field, fungi contamination is very hard to prevent; .  Mycotoxins are very stable substances thus their elimination is a very complex issue; .Mycotoxins can be bound with certain plant nutrients which makes them undetectable to most of the analytic procedures (“masked” mycotoxins); .Different mycotoxins are often produced by the same fungi leading to synergistic effects in the animals; . There are many animal factors influencing animal’s response to mycotoxins (interactant factors).

21. References: [1] Coker, R D (1997). Mycotoxins and their control: constraints and opportunities. NRI Bulletin 73. Chatham, UK: Natural Resources Institute. [2]Miller, J D (1991) Significance of grain mycotoxins for health and nutrition. pp 126-135. In: Fungi and Mycotoxins in Stored Products. Champ, B R, Highley, E, Hocking, A D and Pitt, J I (eds). ACIAR Proceedings No. 36. Canberra, Australia. [3] Van Egmond, H O & Dekker, W H (1997). Worldwide regulations for mycotoxins in 1995 - A compendium. FAO Food and Nutrition Paper 64, FAO, Rome, Italy. [4] JECFA (1996a). Ochratoxin A: A safety evaluation of certain food additives and contaminants. WHO Food Additive Series, 35, pp 363-376. [5] Mycotoxins: Occurrence and Control in Foods(2005). Retrieved from http://www.foodtech-international.com/papers/mycotoxins.htm on 05-13-09 [6]JOURNAL OF FOOD SCIENCE—Vol. 71, Nr. 5, 2006. Retrieved from http://members.ift.org/NR/rdonlyres/62024337-FB0E-4952-AD9F-55E860551809/0/mycotoxins.pdf on 05-13-09

22. References • [7] Schiefer, H B, Hancock, D S and Bhatti, A R (1986) Systemic effects of topically applied trichothecenes. I. Comparative study of various trichothecenes in mice. Journal of Veterinary Medicine, 33A, 373-383.Bhavanishankar, T N, Ramesh, H P and Shantha, T (1988) Dermal toxicity of Fusarium toxins in combinations. Archives of Toxicology, 61, 241-244. • [8] Mycotoxins: (2000): diagnostics & Management International Crops Research Institute for the Semi-Arid Tropics, Patancheru 502324, India. Retrieved from http://www.aflatoxin.info/mycotoxins.asp • [9] AFRO Food Safety Newsletter Issue No 2. July 2006 • World Health Organization Food Safety (FOS). Retrieved from http://www.afro.who.int/des/fos/afro_codex-fact-sheets/newsletter_0706.pdf 0n 05-04-09 • [10]Internationational Crop Research Institute For the Semi Arid Tropics(2009). Retrieved from http://www.icrisat.org/vision/p2_chapter3.htm on 05-09-09 • [11] Mycotoxins and Mycotoxicosis in Tunisia: What do We Know and What Do We Need to Know? (2009). Retrieved from http://www.informaworld.com/smpp/content~content=a907270408~db=all

23. Quiz True or False • 1. Feeds that are visibly moldy are at high risk for mycotoxin contamination? F • 2. The mycotoxin system is composed of six interaction systems. F • 3. High-temperature stress is one of the major determining factors in mold infestation and toxin • production. T • 4. Mycotoxins are included in the toxic substances that often occur in animal feeds, posing a serious menace to animals ingesting them ; for example acting directly and indirectly on pig fertility. T • 5. The color of molds on crops is a good indicator of mycotoxin contamination potential? F • 6. Cultural practices, including crop rotation, tillage, planting date, and management of irrigation and fertilization, have limited effects on infection and subsequent mycotoxin accumulation. T • 7. All nations have the right and the duty to protect their citizens from the harmful effects that undesirable substances in food may cause. T • 8. Determining Critical Control Points (CCPs) cannot be achieved using a well designed decision tree, if necessary, to supplement the knowledge and experience of the HACCP team. F • 9. Aflotoxins are Carcinogenic, teratogenic and immunosuppressive. T • 10. One of the reasons we should study mycotoxins is because they are Ubiquitous in many foods, especially consumable food products in developing countries. T