Mycotoxins of regional importance

There are a number of mycotoxicoses which are not widely occurring, but which are of importance to the exposed populations in the affected regions. Mycotoxicoses which fall into this category (Table 2) include those associated with moulds occurring in both growing and stored forage crops. The moulds and mycotoxins include those which have been associated with a variety of livestock diseases including ergotism, paspalum staggers, ryegrass staggers, facial eczema, fescue foot, lupinosis, slobber syndrome and stachybotryotoxicosis (Lacey, 1991).

Table 2 Moulds and mycotoxins of regional importance

Most farm animals consume pasture crops, either by grazing on the living pasture or by consuming the crops as hay or silage. The crops can be colonized by moulds throughout this period, the development of the moulds and the production of fungi being dependent on the prevailing ecosystem. Growing crops present a variety of micro-environments. For example, the uppermost leaves of a plant will be subjected to extreme fluctuations of temperature and relative humidity, whereas those leaves towards the base of the plant will present a more shaded, moderate, humid environment; the surface texture of the leaf will also effect the micro-environment.

THE SOCIO-ECONOMIC SYSTEM

The socio-economic system describes those social (eg cultural, political) and economic (macro- and micro) factors which will exert an important influence on events within the mycotoxicology system; and which should be most thoroughly addressed when any attempt is made to control the production of moulds and mycotoxins. In some instances, given the complexity and unpredictability of human behaviour, it can be very difficult to intervene successfully within the socio-economic system. However, technical interventions which are designed to alleviate spoilage will only be successfully implemented if they can be accommodated and exploited within the existing socio-economic system. Whenever efforts are made to improve the quality of foods and feeds, it should be clearly established that there is a definite need for a better quality product, and that the community is prepared to bear any associated increase in the cost of the improved commodity.

THE CONTROL SYSTEM

The successful management of interacting commodity systems ('commodity management') requires the co-ordinated inputs of an interdisciplinary team', where the potential advantages arising from the dynamics of the team are realised by fully exploiting the interactions between the skills, disciplines and backgrounds of the individual team members. The team will have the skills required to enable it to operate across commodity systems, identifying those factors which are compromising the quality of the products, and introducing appropriate interventions.

The Control System (Figure 6) illustrates a selection of preventative and curative interventions (measures) which may be utilised for the control of mycotoxins, once the nature of the contamination process has been properly evaluated.

Those factors which are compromising the quality of the products of the commodity system, and leading to the production of moulds and mycotoxins, may be evaluated by the implementation of: carefully designed surveillance studies; recently developed biomonitoring methods, to measure the exposure to mycotoxins of individuals; and socio-economic studies, which address a variety of social, marketing and financial issues (Coker, 1997). The occurrence of moulds and mycotoxins can be alleviated by the application of a variety of preventative measures both before and after harvest including, for example, appropriate pest and disease control measures and good harvesting, drying and storage practices. Once mycotoxin contamination has occurred, it can be alleviated by a variety of predominantly post-harvest measures including processing, detoxification, and segregation (Coker, 1997; FAO, 1999).

A structured, systematic approach to the control of mycotoxins is required, focusing upon the need for preventative control measures, and recognising the intimate interactions that occur throughout commodity systems and related systems.

INTEGRATION OF SYSTEMS

Hazard Analysis and Critical Control Point (HACCP) is a food safety management system that is based upon the systematic identification and assessment of hazards in foods, and the definition of means to control them. It is an important component of an integrated approach to food safety. The inter-relationship of HACCP with other food safety tools is illustrated in Figure 7.

Chapters 2 and 3 describe the adoption of HACCP as a means of effecting the systematic control of mycotoxins, culminating in case studies addressing the control of particular mycotoxin problems.

Figure 6 - The Control System

Figure 7 - Food safety tools: an integrated approach

After Food Safety Management Tools (Jouve 1998)

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