**3.1. Impact of mycotoxins on human and animal health in Africa**

#### *3.1.1. Impact of mycotoxins on human health in Africa*

The most significant impact of mycotoxin contamination in Africa has been shown to be on human health. A World Bank report in 1993 observed that the various health problems modulated by exposure to mycotoxins accounted for up to 40% of lost disability-adjusted life years (DALYs) [27], and it is no doubt that Africa is the most affected. In 2004, an outbreak caused by food poisoning with AFs occurred in Kenya, where 317 cases of illness were reported and 68 of the persons were children below the age of 5 and 90 were from 5 to 15 years. In this incidence, at least 123 deaths were recorded [28–30]. In sub-Saharan Africa, about 250,000 deaths are caused by hepatocellular carcinoma annually and this can be linked to risk factors such as AFs and high prevalence of hepatitis B [31]. AF contamination in groundnuts and maize in Nigeria contributed to 7761 liver cancer cases, which results in a total burden of 100,965 DALYs [32]. In 2014, due to AF contamination, about 3334 cases of hepatocellular carcinoma was calculated in Tanzania, 95% of which ended as deaths resulting to a loss of 96,686 DALYs [33].

**2.2. Factors that facilitate the prevalence of mycotoxins in Africa**

attendant mycotoxin production in agricultural commodities.

socio-economic impact of these fungal pollutants on the African continent.

**3. Socio-economic impact of mycotoxin contamination in Africa**

health and economic empowerment are all undisputable evidences to this fact.

**3.1. Impact of mycotoxins on human and animal health in Africa**

*3.1.1. Impact of mycotoxins on human health in Africa*

Mycotoxin contamination have contributed significantly to the elusive sustainable development in Africa. The ever daunting and manifest challenges to food safety and security, good

The most significant impact of mycotoxin contamination in Africa has been shown to be on human health. A World Bank report in 1993 observed that the various health problems

temperature and CO2

6 Mycotoxins - Impact and Management Strategies

The prevalence of mycotoxins in African food and feed commodities have been well documented in literature, and major factors that contribute to this have been identified as climate change, poverty, limited/lack of awareness, pro-regulation and legislation, poor agricultural practices, amongst others. Climate change has in fact been proposed as probably the most serious environmental issue facing our planet [21], and Africa has been the most affected. In fact, 2016 was identified as the hottest year in about a century, and accordingly, a manifestation of this was the 2016 *El-nino* drought episode of Southern Africa, which resulted in agricultural losses amounting to millions of US dollars (US\$). Such imbalances, drastic changes in rainfall,

colonization of crops by mycotoxigenic fungal genera [22]. Since mycotoxin production is climate dependent, changes in climatic conditions have been suggested and proven to lead to possible drastic modifications in fungal population and attendant mycotoxin production [23, 24]. These would not only favour the emergence of new mycotoxigenic fungal strains, but also

Africa is the poorest continent in the world [25]. Nearly one in five people living in Africa is undernourished and/or go hungry, the highest prevalence of such in the world [26]. This can have a huge significance on the quality of food commodities consumed in Africa. There are limited resources to adopt relevant technologies/systems to control mycotoxins proliferation, and in dire need for food and "quenching" hunger, the quality and safety of food ingested is totally irrelevant (even though visibly contaminated). Under such circumstances, having food is much more vital and subsequently prioritized. Further to this, limited public awareness on the mycotoxins issue has been identified as a critical factor on the prevalence of mycotoxins in Africa. Knowledge is power. The available information on the incidence, public health importance, prevention and control of mycotoxins in many African countries is still grossly lacking, with no indication that such will be addressed anytime soon. Equally important is the lack of appropriate mechanisms to promote and educate consumers on the harmful effects of mycotoxins, good agricultural practices and post-harvest handling of commodities. Due to all these factors, the issue of mycotoxins on the continent has remained infamously persistent, with attendant grave implications. The next section of this chapter discusses in detail the

patterns could increase the risk of pathogen migration and influence

Based on several studies in Southern Africa, AFs contamination have been strongly linked with child undernutrition, increased mortality and morbidity due to their negative effect on micronutrient absorption and immune function [34]. In addition to these, immune disruption by AFs may aggravate health impacts of principal diseases plaguing Africa such as malaria, kwashiorkor and HIV/AIDS [35]. In Nigeria, posthumous autopsy of infants who suffered from kwashiorkor showed a significant level of AFs in their brains, because of consumption of contaminated maize based gruel [36]. According to Jolly *et al.* [37], high levels of AFB<sup>1</sup> and acute aflatoxicosis symptoms were found within Ghanaian population that also had abnormal liver function and high level of HBV infections. Turner *et al*. [38] reported decreased levels of secretory immunoglobulin A (IgA) in Gambian children exposed to AFs. In Kenya, the mean birthweight of the children of women exposed to AFs prenatally was lesser than that of those who had not been similarly exposed [39].

In the Gambia, maternal dietary intake was indicated to be an important factor in carcinogenic-induced damage in the unborn baby, due to a highly significant correlation between AF-albumin adduct levels in the mothers venous and respective cord sera [40]. In the same country, children with reduced level of salivary Secretory Immunoglobulin A (sIgA) have been linked with exposure to AFs [38]. The consumption of FBs contaminated maize have been correlated to the high incidence of oesophageal cancer in parts of South Africa [41] and Malawi [42]. According to Ferlay *et al*. [42], Malawi has the highest prevalence rate (24.2 per 100,000 persons) of oesophageal cancer in the world. ZEA as a naturally occurring endocrinedisrupting chemical has been implicated in the manifestations of gynecomastia with testicular atrophy in rural males in Southern Africa [43]. In 1977 to 1978 an outbreak of ergotism occurred in Wollo, Ethiopia where 140 persons were affected, four children lost both or at least one leg and the mortality as high as 34% [44]. In North Africa, particularly Tunisia and Egypt, cases of human nephropathies have been strongly associated with elevated exposure to OTA and outbreaks of ochratoxicosis, *i.e*., illness due to ochratoxin exposure [45–47]. Alpha-ZEA has been implicated as a potential risk factor for breast cancer in Tunisia [48]. Likewise, high levels of OTA in Moroccan foods and other agricultural commodities have been linked to some chronic illnesses [49, 50]. **Table 1** shows some other mycotoxins and the toxic effects they provoke on human health. Further studies are required to establish the association between other poorly investigated diseases and dietary exposure to other mycotoxins (emerging, modified and multiple mycotoxins).

Though tremendously difficult to estimate in Africa, the net monetarized impact of mycotoxins on human health in Africa [including physical pain, death (in severe cases), temporary or permanent impairment, loss of productivity, costs of diagnosis, treatment, hospitalization


amongst dogs through the consumption of contaminated dog food. The first occurred in 1987 where 10 cases of fatality were reported, and histopathological evaluation revealed chronic symptoms of necrosis, bile duct proliferation, hepatocellular fatty degeneration, fibroplasia etc. were observed [69]. The second episode occurred in 2011, where over 220 dogs died and several others were affected in the Gauteng province. Subsequent clinical examinations revealed that the dogs were exposed to highly contaminated feed (with levels of AFs ranging from 5 μg/kg and 4946 μg/kg), which is well above regulatory limits [70]. In addition to AFs,

Mwanza *et al.* [72] evaluated the productivity and general health of domesticated animals in Limpopo Province of South Africa in relation to fungi and mycotoxin contamination, the results revealed that these animals were at risk to mycotoxin contamination which possibly plays an important role in abortions, low productivity, chronic and acute diseases, as well as reduced immunity in these animals, which are similar effects often seen in other rural communities in the country, as well as other parts of Africa, however, no clinical investigation is

The CTA has clearly alarmed that mycotoxins significantly threatens achieving food security and safety in Africa, which is one of the UN's sustainable development goals [5]. Food supplies are limited and often of poor quality, with mycotoxins proliferation frequently implicated as the culprit. About 35% of global food and feed produce is contaminated by mycotoxins. The attendant food losses/wastages is in the ranks of 1 billion metric tons annually [73–75], and there is little doubt that majority of these losses come from Africa. In a continent where about 60% of the populace are farmers (mainly at a subsistence level), and majority of households relay on their homegrown food for survival, these statistics on mycotoxins are disturbing. The eminent reality of global warming further complicates the situation as Africa is the continent that is most affected due to its position at the equator. A recent study predicts that fungal pathogens and pests are proliferating at a rate of 5–6 km annually from the equator to polar regions of the earth [76]. Drought and plant stress makes crops more susceptible to diseases and fungal attack, and consequently increases mycotoxin contamination, which reduces crop quality and yield, as well as decreases in livestock productivity, disease tolerance and fertility. Moreover, adaptation of known mycotoxigenic fungal species to climate change conditions could result in a more aggressive and invasive behaviour of the fungi leading to colonization of new territories, increased production of mycotoxins, and perhaps the potential of producing entirely new mycotoxins, which poses a significant threat to food security, safety and

usually conducted to determine the possible causes of such illness/effects [72].

**3.2. Impact of mycotoxins on food security in Africa**

health in Africa and other developing countries [76–78].

**market brand**

**3.3. Impact of mycotoxins on trade and damage to the African agricultural export** 

Mycotoxins affect trade in Africa majorly by reducing the value of commodities offered for sale. Reduced value can manifest at different trade levels through the lowering of prices, inspection cost, disposal, rejection of lots or treatment of lots at additional cost prior to sale, compensation in case of claims and cost of sampling and analysis along the value chain. Not less than 2.3 million bags of maize were found unsuitable for marketing (as well as consumption) during the outbreak of aflatoxicosis in Kenya from 2004 to 2006 [79]. Following another AF alert in Kitui,

, ZEA, and OTA were all later implicated in this outbreak [71].

The Socio-Economic Impact of Mycotoxin Contamination in Africa

http://dx.doi.org/10.5772/intechopen.79328

9

other mycotoxins such as FB<sup>1</sup>

**Table 1.** Mycotoxins and their toxic effects on human health (adapted from Capriotti *et al*.) [51].

and health care (morbidity), cost of anxiety, pain, misdiagnosis, suffering and reduced life quality etc.] could be enormous, and demanding on national budget. A case in point, a study conducted in Gambia observed that diseases consistent with mycotoxin exposure (in particular Hepatitis B and its associated medical complications) results in a total monetized DALY worth over 94 million US\$ of GDP, which equals 9.4% of the nation's GDP. This is a huge loss to the health of the populace and country [67]. Similarly, in Senegal, the cumulative cost in terms of health due to AFs is estimated at no less than 92 million US\$ of the nation's GDP [67]. In 2014 in Tanzania, the economic impact (in monetary terms) of AFs was estimated between 6 million and 264 million US\$ due to the resultant health impact [33].

#### *3.1.2. Impact of mycotoxins on animal health in Africa*

Very little work has been done on the health impact of mycotoxins on animals in Africa. This is understandable as the health effects and losses in animals (such as feeding efficiency, infertility, meat, milk and egg quality losses, susceptibility to diseases etc.) are subtler to decipher. Moreover, in Africa, people have limited resources and may prioritize the care of humans above the 'waste of resources' on animals. To this effect, when mouldy cereals are too bad to be consumed, they are usually not disposed, but blended with non-mouldy ones and used as animal feed, or in some cases fed directly to the animals. However, monogastric farm animals such as poultry, swine and dogs are at particular high risk, because their basal diet (feed) is made up of cereals [68]. These animals also lack reservoir that harbours microorganisms that can break down secondary metabolites of fungi before they are absorbed into the intestine. In South Africa, there have been two episodes of aflatoxicosis (illness resulting from AFs) amongst dogs through the consumption of contaminated dog food. The first occurred in 1987 where 10 cases of fatality were reported, and histopathological evaluation revealed chronic symptoms of necrosis, bile duct proliferation, hepatocellular fatty degeneration, fibroplasia etc. were observed [69]. The second episode occurred in 2011, where over 220 dogs died and several others were affected in the Gauteng province. Subsequent clinical examinations revealed that the dogs were exposed to highly contaminated feed (with levels of AFs ranging from 5 μg/kg and 4946 μg/kg), which is well above regulatory limits [70]. In addition to AFs, other mycotoxins such as FB<sup>1</sup> , ZEA, and OTA were all later implicated in this outbreak [71]. Mwanza *et al.* [72] evaluated the productivity and general health of domesticated animals in Limpopo Province of South Africa in relation to fungi and mycotoxin contamination, the results revealed that these animals were at risk to mycotoxin contamination which possibly plays an important role in abortions, low productivity, chronic and acute diseases, as well as reduced immunity in these animals, which are similar effects often seen in other rural communities in the country, as well as other parts of Africa, however, no clinical investigation is usually conducted to determine the possible causes of such illness/effects [72].
