NC1025: Mycotoxins:Biosecurity and Food Safety (NC129)
Statement of Issues and Justification
Mycotoxins are metabolites of fungi that can adversely affect animal and human health. Mycotoxins can be produced in grain during storage or processing, but are most frequently associated with fungal infection that occur before harvest. Environmental factors that determine fungal infection and mycotoxin production are complex. Generally, a basal level of mycotoxins is present in US grain; however, in some years, environmental conditions lead to localized or widespread outbreaks of mycotoxin contamination. However, there is no organized monitoring system for tracking the incidence and severity of mycotoxin contamination at either the national or regional levels. Although breeding and transgenic technologies have shown promise for reducing the risk of mycotoxin contamination of grain, to date no commercial variety of any major US crop is available with either genetic or transgenic resistance to mycotoxin contamination.
The need, as indicated by stakeholders, and likely impacts from completion of the work. For grain and livestock producers, the most important issues are preventing mycotoxin contamination and reducing the effects of mycotoxins on livestock. For grain buyers and food processors, the primary issue is being able to rapidly assess the quality of grain as pertaining to mycotoxins and mycotoxigenic fungi. The worst-case scenario for these stakeholders is to own millions of bushels of corn contaminated with unacceptable levels of aflatoxins and fumonisins, or wheat with excessive concentrations of deoxynivalenol (DON). Rapid methods to detect mycotoxins at the first points of sale (elevators) as well as methods to detect mycotoxigenic fungi in the commodity (e.g. DON-producing Fusarium in barley) would address these concerns. Additionally, these stakeholders need cost-effective methods to detoxify mycotoxins and prevent further deterioration of contaminated grain. The lowering of tolerance limits for mycotoxins in overseas markets has increased the burden for grain buyers and food processors; currently, levels of mycotoxins that are acceptable for some US products are unacceptable in European and Asian markets resulting in non tarrif trade barriers. New methods to monitor and treat contaminated grain would benefit domestic consumers and would allow American commodities to compete more effectively in foreign markets. Finally, workers who are responsible for animal and human health need information about the toxicity, carcinogenicity, modes of action, and biomarkers of exposure and disease for all categories of mycotoxins. This information would be used to train health-care providers to identify exposure and treat related disease, as well as to develop accurate risk assessment recommendations.
The objectives outlined in this proposal will address the needs of the stakeholders. Objective 1 deals with the need for information applicable to the risk assessment process. The research team working on this objective will look specifically at the toxic effects of fumonisin and fumonisin conjugates. Animal models, target species and cell cultures will be used to determine the effects of the mycotoxin on the whole organism, target organs, cellular and subcelluar changes, and gene expression. Objective 2 addresses the stakeholders' continuing need for new detection methods. A team of researchers will 1) evaluate new antibodies to detect the presence of fumonisin, DON and other mycotoxin analogs present after processing, 2) develop a library of PCR primers for detecting mycotoxigenic fungi, and 3) develop and evaluate optical detection technology that detects fungal-contaminated commodities. In addition, this NC group of experts will serve as an unique resource to address mycotoxin issues as they relate to potential bioterrorism or outbreaks of plant, animal or human disease. No other such group exists in the US.
These studies will provide new information on mycotoxin detection, detection of fungi that produce mycotoxins, and the non-destructive detection of contaminated grain. Objective 3 will address the need for management procedures that help prevent mycotoxin-related problems during grain handling, storing, processing and feeding. Finally, the goal of the team working on Objective 4 is to provide basic knowledge about the biochemical and molecular factors that regulate the biosynthesis of aflatoxins and fumonisins. This will reveal critical points in the regulation where targeted inhibitors could be designed.
The importance of the work, and consequences if it is not done. Hazard assessment includes exposure assessment and evaluation of toxicity, both are essential. The proposed research is wide-ranging and could lead to negative consequences if not completed. First of all, the presence of mycotoxins is an important health hazard. We propose basic research to define the toxicity of several important mycotoxins. Without this information, it is impossible to assess risks associated with mycotoxins. Additionally, the presence of mycotoxins in grain is an economic concern, especially in the context of global markets. Without an aggressive research program to prevent, treat and contain outbreaks of mycotoxins in grain, US grain producers will suffer the consequences of reduced marketability of their products. Furthermore, the proposed research addresses biosecurity concerns. The natural occurrence of mycotoxins in grain is an important security concern for the grain industry and end-users of grain; mycotoxins have been used as agents of terrorism, e.g. aflatoxin in Iraq. . Without a proactive research program to find innovative ways to monitor and treat mycotoxins, US agriculture faces the consequence of being unprepared for a mycotoxin outbreak, regardless of its origin. Finally, the production of mycotoxins represents a basic aspect of agricultural science. Improving our understanding of how mycotoxin biosynthesis is regulated will not only lead to novel treatment strategies, but may also advance our understanding of fungal pathogenesis in general.
The advantages for doing the work as a multistate effort and the technical feasibility of the research. The scientists involved in this multistate, multidisciplinary research proposal work individually on mycotoxin issues related to their respective disciplines and areas of expertise. Just as agriculture is diverse and varies greatly from state to state (and in many instances, within a given state), the occurrence and severity of mycotoxin outbreaks vary widely across the US. A multistate effort ensures a thorough approach to investigate a complex and highly variable phenomenon. Due to the wide range of experience and expertise of the group, the proposed research should be technically feasible.
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