Aside from the obvious social implications for public health (see the toxic effects of individual mycotoxins, later on in this chapter), the occurrence of mycotoxigenic fungi and mycotoxins in food and feed chains has also major economic impacts to humansociety. These include (1) reduction of crop output due to plant diseases and from the removal of infected and/or damaged product (sorting), (2) reduced quality and commercial value of produce, (3) reduced animal productivity due to health problems associated with consumption of mycotoxin-contaminated feed, and (4) costs for humans and animals health care (Schmale and Munkvold, 2014b). The extra production expenses for the control of mycotoxigenic fungi outbreaks, such as the use of selected resistant cultivars and fungicides spraying or for the adoption of specific measures of prevention (e.g., biological control) have also to be taken into account. At post-harvest, the multiple control strategies that have been developed to mitigate the mycotoxin risks in the course of storage, transportation or processing and the cost for the organization and functioning of a surveillance network are all additional burdens for farmers, handlers, processors and, ultimately, for consumers.
Estimations of the costs of mycotoxins are not available for all the world regions. In the USA, the total cost has been estimated 0.5–1.5 billion USD per year; Council for Agricultural Science and Technology CAST (2003) reports a yearly cost of 0.9 billion for crop losses of corn, wheat, and peanuts plus an additional 0.5 billion for regulatory enforcement, testing, and quality control measures. In developing countries, it is likely that losses exceed those in the USA. For instance, in three Asian countries (Indonesia, Philippines, and Thailand) annual losses were estimated at 0.9 billion USD for aflatoxins only (Schmale and Munkvold, 2014b).
Even if prevention measures are enforced, sometimes these are not effective enough to avoid the occurrence of mycotoxins at levels close or above the maximum allowable levels for food, resulting in low quality and reduced price of the produce or, in the worst scenarios, in rejection of lots or diversion towards alternative and low revenue uses, such as feed production or conversion to bioethanol. Many staple agricultural commodities such as wheat, rice, barley, corn, sorghum, soybeans, groundnuts and oilseeds are at high risk of mycotoxin contamination. For this reason, regulations on allowable levels of mycotoxins in staple food have been set and are strictly enforced by most countries. However, standards vary greatly among countries, particularly between developed and developing countries, and this difference may cause major trade issues in the globalized market. For some developing countries, where agricultural commodities account for a large part of the total national export, the economic impact of rejection of mycotoxin-contaminated products, as for both lost trade and additional costs for inspection, disposal and compensation in the case of claims, is considerable (Gbashi et al., 2019; Taniwaki et al., 2019). Also, the stricter mycotoxin standards for imported products applied in the developed countries may prompt the developing countries to export their best quality foods and keep the more heavily contaminated foods for domestic consumption, resulting in higher exposure of people to mycotoxins in those countries. This situation raises ethical and social issues and highlights the need for a more effective international cooperation on the fronts of standards harmonization and scientific research (Logrieco et al., 2018). The climatic conditions in developing countries of the tropical zone favor proliferation of mycotoxigenic fungi and the accumulation of mycotoxins. Mycotoxin mitigation measures are costly and the control strategies should be implemented at multiple points of the production chain, through an organized and coordinated infrastructural system of control, surveillance and communication, which in some developing countries may be difficult to set (International Agency for Research on Cancer IARC, 2012b). To successfully implement such a system it is important that the expected benefits, in terms of trade and health, exceed their costs. In this sense, the role of scientific research for the development of effective low-cost mitigation strategies is of utmost importance.
While the human health losses from adverse effects of mycotoxins are primarily relevant to the social impact of mycotoxins, they have also economic impacts that can be evaluated by the tools of health economics. This cost can be calculated in two ways. The first is cost of illness, which is mainly relevant to developed countries because a large portion of the cost is health-care related. The second is disability-adjusted life years, which is applicable to both developed and developing countries (International Agency for Research on Cancer IARC, 2012b). Vardon et al. (2003) estimated the total losses due to the three main mycotoxins, aflatoxin, fumonisin and deoxynivalenol, in the USA to be as high as 1 billion USD per year; this cost was largely due to market losses, because human health effects are almost negligible in countries where a strict regulation and an effective surveillance are enforced. On the contrary, in the developing countries the loss should be calculated as a combination of market impacts, mainly due to rejection of contaminated lots, and adverse health effects on local consumers (Gbashi et al., 2019).
