Water is an important resource that supports life on earth.
Its availability plays key roles for attaining socio-economic developments
globally. It is also a priority toward meeting the United Nations Sustainable Development
Goal (SDG) 6 that seeks to ensure access to water and sanitation for all. Water
is thus an essential resource for balancing the well-being of humans and
healthy ecosystems.
The survival of humans and continuing social-economic
developments depend on the supply of appropriate water quality and quantity.
The relationship between humans and ecosystems is core as people strive to
improve their well-being. Ecosystem services are beneficial to all living
creatures including humans in a number of ways. Water, for instance,
contributes to ecological functions through the provisioning of habitat for
aquatic life, including fish that is food for humans.
Water also provides ecosystem services that include
freshwater supply, regulatory functions such as dilution and water
purification, and fulfilling cultural necessities (e.g., water for traditional,
esthetic, or medicinal and spiritual purposes). The benefits derived from
ecosystem services are available to humans, regardless of where they live or
where the services are generated. For example, urban dwellers enjoy river
ecosystem service benefits including fishing for food or growing trees along
the river banks, which can be used as timber to build houses or as firewood for
cooking.
Ensuring sustainable management of aquatic ecosystems for
improved food security is therefore important. This is especially true in urban
areas where human activities may pollute distant ecosystems through effluent
discharges caused by industrial and domestic or mining activities. Human
activities can pollute water bodies and impact socio-economic developments
negatively. Any changes in water quality can affect short- or long-term food
security goals if aquatic resources are not properly managed.
Water and human
survival
This section seeks to highlight the basic human need for
water and track the global water distribution and its importance in food
security. Water is a basic unit of life and an essential nutrient that is
required in amounts that exceed the body’s ability to produce it. Like all
nutrients, water performs different functions in the body. Water is an
essential component of cells, tissues, and organs required for digestion,
absorption, and dissolution and as a carrier for nutrients, eliminating waste
products; temperature regulation; and as a lubricant and shock absorber.
To achieve all these functions, total body water must be
approximately 60% of body weight in males and 50% of body weight in females.
The water distribution is up to 60% intracellular (this amount is lower in
females due to larger amounts of subcutaneous tissue and smaller muscle mass) and
20% in extracellular space. The extracellular fluid compartment comprises fluid
in blood, interstitial fluid, bone, connective tissue, and transcellular fluid.
Variation in water intake depends on human health, weight, and human physical
performance.
Human survival can be achieved with minimum water
requirement where water lost through normal activities gets replenished. The
average adult body naturally loses almost 2–3 L of water daily which must
be replenished to function on a day-to-day basis. This loss occurs mainly via
urine, perspiration, feces, and exhaled air.
The amount of body water that gets lost depends on
individual and environmental factors. These factors are affected by the climate
a person lives in, his or her age, physical activity level, and kidney function.
To regulate the body’s water levels, the water input must balance water output
through metabolic processes (0.3 L/day), fluid intake triggered by thirst
(1.5 L/day), and solid foods triggered by appetite (approximates
0.7 L/day). Too little or too much water in the body can lead to
less-than-optimal body function.
Early stages of decreased water intake in the form of
dehydration can lead to difficulty in concentrating, headache, and sleepiness.
Decreased water intake has also been associated with bladder and lower urinary
tract cancer and increased risk of colorectal cancer as well as kidney stone
formation. Taking too much water can also put an unnecessary burden on the
cardiovascular system and the kidneys and can cause a drop in the concentration
of electrolytes in cells causing harm in the long run.
While water may be a renewable resource, it is unfortunate
that there is only a finite amount and there are no substitutes. Without clean
and safe water, human survival cannot be achieved. This has a great impact on
the global burden of disease, health, education, and economic productivity of
populations.
Water challenges
affecting human survival
Water is an important component in a number of human
functions, hygiene, and the overall maintenance of health. At the most basic
level, water service must meet consumption and hygiene needs and sustain good
health at household level. Millions of the world’s poorest people, however, die
each year from preventable diseases due to poor hygiene, lack of clean drinking
water, and lack of proper sanitation facilities.
The reality is that water and sanitation are weakly
integrated into countries’ poverty reduction strategies. Many national
governments are failing to put in place the policies and finances needed to
accelerate progress toward achieving clean water and adequate sanitation.
In many rural communities, lakes, dams, and stream that are
the main sources of water run dry for long periods, forcing people to use
unsafe water sources. For the 2.1 billion people who lack access to clean
water, they can only afford to get a measly 5 L a day and fail to meet the
recommended basic minimum of 20 L a day required for human health, economic,
and social development. This is a far cry from the 200 L a day per person
that people from rich countries consume on average in a day.
A report on global distribution of the global drinking water
services in 2015 found that 71% of the global population (5.2 billion people)
had access to a safely managed drinking water service. The report further found
that sub-Saharan Africa was the region with the lowest number of people with
access to safe drinking water located on their premises. Only Australia and New
Zealand had 100% access, where all of the population had basic services
(including basic drinking water, sanitation, and hygiene) in their households.
The same report estimated that two-third of the total global
population was living in water-stressed areas that experience water scarcity
for at least 1 month in a year in 2015. Of the two-third, 844 million
people lacked basic drinking water service and 263 million people were reported
to be spending over 30 minutes per round trip to collect water from an
improved water source.
Still, 159 million people were reported to collect drinking
water directly from surface water sources and over half of these people were
living in sub-Saharan Africa. These people share their domestic water sources
with animals. A large fraction of the people that live in extremely vulnerable
situations of water scarcity all year-round are found in Libya, Somalia,
Pakistan, Morocco, Niger, and Jordan where 50–90% of the country’s population lives
under those circumstances.
Global distribution
of water
An estimated three fifth of the earth’s surface is covered
by water, which makes up a total volume of almost 35 million km3. Of the
available amount, only 200,000 km3 (1%) of this is fresh water that
is usable by humans. This is the water that is expected to fulfill the demands
of the increasing global population, meet the food production needs using the
limited amount of arable land, and sustain industrialization.
Historically, people looked for location to set up their
livelihoods near water supplies such as river bases that could provide drinking
water and carry off waste. Over time, areas close to water sources became
populated by industries and agricultural holdings which use water for irrigation
and also to power industries.
Distribution of piped water is realized as a sign of
progress toward achieving the SDGs. Industrialized countries (20%) have managed
to achieve piped water coverage in 85% of their entire household. The poor
countries, however, have only managed limited piped water coverage with only
25% of all their households having access. Industrialized countries have been
better able to achieve water security compared to poor countries and this is
evident from the average water usage data of 200 L per person per day in
rich countries compared to the 5 L per person per day in poor countries.
Factors that contribute to high water scarcity levels
include areas with a high population density, areas with irrigated agriculture,
and areas with very low natural water availability. Geographically, water
scarcity can be found in in the world’s arid areas with low water availability
like the Sahara, Taklamakan, Gobi, and central Australian deserts.
Water scarcity has also been found to be intense in areas
with high population density and irrigation intensity. Globally, these areas
are found near river basins and include the Ganges basin in India, the Limpopo
basin in Southern Africa, and the Murray-Darling basin in Australia.
Distribution by sectors shows that water use is spread
between domestic, agriculture, and industry sectors. Agriculture accounts for
over 70% of freshwater use and industry
water use accounts for 20% globally. In spite of this, it is believed that
there is enough water in the world for domestic, agriculture, and industry
purposes; the only problem is how this water is distributed especially to the
poor who are systematically excluded from the distribution.
Water use varies significantly by sector across the world. How do these
three sectors use fresh water?
Agriculture
As discussed above, water use varies considerably across the
world especially between the poor and rich. Agriculture is the biggest user of
fresh water with Africa and Asia, accounting for the largest users under this
sector with an estimated 85–90% of all freshwater. Future demands for water for
agriculture are threatened by climate change, technological development, and
urbanization. The challenge is to produce more food to meet the growing
population demands using less water and other resource inputs in an
environmentally friendly manner. Low-income countries’ average agriculture
usage is estimated at 90%; 79% for middle income and only 41% in high incomes
countries.
Industry
Industrial water use includes all the water used for
manufacturing, energy generation, and other industrial activities such as
dilution, steam generation, washing, and cooling of manufacturing equipment.
Globally, an estimated 20% of total available fresh water is used for
industrial purposes. Within the industrial sector, hydropower and nuclear power
generation uses 57–69% and the thermal power generation uses 0.5–3%. Industries
also pose a threat to fresh water because of the amount of wastewater it
produces, its mobility, and loading of industrial pollutants and their potential
impacts on water resources, human health, and the environment. High-income
countries tend to use the largest portion of water on industries (17%), with
low-income countries using the least with an average 2%.
Domestic
Domestic water is the most visible form of water and it
shows the problem that exists in the distribution of fresh water between the
rich and the poor. People in developed countries consume almost up to 10 times
more water daily than those in developing countries. In developed countries,
where large cities have centralized water supply and an efficient canal system,
domestic consumption averages 200 L per person per day.
In developing countries within Asia, Africa, and Latin
America regions, consumption in cities and towns is between 50 and 100 L
per person per day, and in the water scarce areas within these regions, the
amounts can be as low as 5 L per person per day. Countries with the
largest population, China followed by India, have the highest water use
globally.
The change in water distribution will have a serious
implication on people’s health and well-being, especially for people living in
high population density areas, areas with irrigated agriculture, and areas with
very low natural water availability. These are the estimated 1.8–2.9 billion
people who experience severe water scarcity for at least 4–6 months per
year and the 500 million people face severe water scarcity all year round.
The distribution of water between sectors is expected to
change over the coming years as a result of population growth, increased water
scarcity, and drought due to climate change. Water use for irrigation and other
water using sectors of the economy are expected to experience extreme
competition which will place more burden on food security.
Water in food
security
Water forms an essential part in national food security. To
attain food security, there must be an acceptable quantity and quality of water
for health, livelihoods, ecosystems, and production. Any sustainable attainment
of food safety and security for a fast-growing population requires thoughtful
decisions to develop and manage water resources.
Food security and safety are key development agenda items in
most developing regions (Global Panel on Agriculture and Food Systems for
Nutrition, 2016). Global research and funding have been prioritized and
channeled toward fighting against food insecurity. Although substantial
progress globally is evident, the same cannot be said for some of the African
regions. Sub-Saharan Africa continues to have less access to sufficient
quantity and quality food for proper health and growth. The report also
classified the sub-Saharan countries as food insecure, with limited access to
safe food within their population.
Despite the global food security achievements realized in
recent years, food security and limited access to food safety still remain as
challenges in Africa. Water scarcity and irregular rainfall distribution are
proving to be an impediment to Africa’s efforts to ensure food security.
Agriculture production systems, which are the backbone of food security, are
also adjusting to tightening water availability by reducing freshwater use
especially in the African region. This has resulted in the emergence of new
diets that are sensitive to the significant influences of water and land use.
As the water challenge for agricultural production in Africa
increases, it is expected that the share of irrigated agriculture in global
water use could rise by over 30% by 2030. Total global water demand could
double by 2050. The increased competition for scarce water and land resources
increases concerns about where the additional food will come from. The
challenges are further exacerbated by climatic changes that cause
irregularities in water availability across the African landscape.
Water requirements in agriculture vary significantly not
only in terms of quantity, but also in terms of quality and timing depending on
food type. This is very significant especially when it comes to staple foods
such as maize, rice, and wheat that are critical in food security of many
countries in Africa. Some of these countries have increased awareness toward
conserving their national water supply by opting for virtual water
trade—importing food from outside the country in the effort to conserve water
resources and maintain food security. Other countries have shifted food
production within the agriculture sector focusing more on planting
water-efficient crops.
Apart from water being important in production, it also
plays a huge role in food processing, transformation, and preparation adding to
the competition against industrial and domestic water use. Even though food
processing uses much less water than primary production, this part of the food
system requires water that is of high-quality standards and that does not pose
any health and safety risks on both human and ecosystem health.
There is also a drive toward introducing water-use
efficiency, reducing pollution impacts from processing industries. Poor quality
water used in food processing can lead to food-borne disease such as diarrhea
and other diseases that contribute to malnutrition. The unsafe food creates a
vicious circle of diseases affecting particularly the more vulnerable
populations that include children, the elderly, and the sick.
Priority must be given to encouraging greater efficiency of
water use and the development of integrated water management plans. The
shortage of food production due to water scarcity calls the need to manage
every water drop to attain food security and food safety in Africa. This raises
awareness that water for agricultural production is a pressing issue.
It has been noted that agricultural developments require a
consistent and sustainable provision of large quantities of good quality water
for food security. The present situation is a clear sign that previous
potential solutions to solving Africa’s food insecurity have not received the
most needed attention when defining development goals on the continent.
Societies depend on water availability to meet a wide range of needs including
water for irrigation, domestic, and industrial use.
Poverty and water are inextricably intertwined. Food
security cannot be achieved without tackling water issues since lack of safe
water underpins food insecurity. Countries continue to invest in the protection
and management of water resources to continue deriving benefits for improved
living standards. Undoubtedly, major water investments in agriculture are
necessary toward meeting food production needs. Crucial role players are needed
to put together efforts to conserve water for a food secure world.
Water scarcity
impacts on food security
Many Africans depend on aquatic and riparian plants and
animals as an important source of food for both humans and livestock. These
include fish, shellfish, bait, edible plants, and grazing. In addition, some
areas such as wetlands and floodplains across Africa may be used for the
cultivation of food crops. In this way, these riparian areas contribute to food
security and livelihoods. These services are of particular importance to poor
communities.
Nonetheless, the provision of reliable sources of water
whether for small-scale water for food processing or large-scale water for
irrigation is necessary to move beyond subsistence farming toward a more food
secure continent. The availability of water allows farmers to continue growing
crops of high value such as vegetables, which are highly sensitive to water
stress periods.
Although quality of water is crucial for peoples’ nutrition
and water availability for food security in developing countries, water
investments have been rapidly declining. While irrigation has a high potential
for environmental damages or disturbances, it has contributed positively to
poverty eradication. Irrigated agriculture has benefited both rural and urban
poor by lowering food prices. The availability of water for irrigation means
less people fall below the poverty line, and that poor communities, women in
particular, also benefit greatly from irrigation as a major source of water for
most of their domestic uses, fishing, small and/or informal businesses.
Nonetheless, small-scale water availability can impact on
food security positively. The availability of water for small-scale harvesting
has a huge effect on incomes and food security in developing and poorest
communities. Major water investments will have more drastic and positive
impacts on the poorest communities, where the majority of people live on less
than US$1 on a daily basis.
Existing challenges between water availability, quality, and
sustainable agriculture linkages must be explored and be made explicit in
planning potential agriculture-based strategies for improving food security.
The need for fresh clean water is, however, threatened by the changing quantity
and quality of the freshwater resources on which people depend for survival.
The need for clean water is also linked to adequate sanitation and improved
health. Proper sanitation helps to protect water sources from bacterial, viral,
and protozoal agents that cause water-related diseases. The concern for many is
how can water quality be attained?
Water quality
management
As much as water is an essential component of life, it is a
hotbed for carriers of many diseases caused by consuming unclean water. Access
to safe drinking-water, sanitation, and hygiene (WASH) services is an important
element of food security and has a positive impact on nutrition. A number of
approaches are used to assess water pollution effects on the ecosystems which
have a direct contribution to food security and nutrition.
A common approach is to use chemical indicators to measure
the concentration of chemicals or toxicants within a water body using either
water samples or direct in-stream measurement of the water source using water
samples as (chemical indicators). If the chemicals within the water are in
exceedance with acceptable limits, that water system is regarded as polluted
and not fit for human consumption. Biomonitoring can also be used to assess
water quality by examining the presence or absence of certain species or
organisms in a water body.
Another approach that is used to assess water pollution is
ecotoxicology. An investigation is conducted to examine responses of insects,
fish, and other invertebrates to a chemical or stressor as biological
indicators of water quality. Thus, polluted aquatic systems may not adequately
support the provision of fish and insects as food for humans. Similarly,
necessary microbes that support plant growth in soils may not thrive in
polluted environments, thereby affecting food security.
Without good quality water, the lives of millions of people
especially young children are at risk of dying from preventable diseases caused
by poor water, and a lack of sanitation and hygiene. There is a growing interest
to better understand and measure the effect of programs and approaches not only
directed toward improving water management in agriculture and food production
but also to include integrated approach to implementing safe water and adequate
sanitation. Approaches and practices for ongoing efforts to better link WASH
and nutrition programs integrating WASH into food security and nutrition
programs are discussed in the following section.
Water, sanitation,
and hygiene (WASH) programs and food security
The World Health Organization report defines drinking water
as water with acceptable quality in terms of its chemical, bacteriological, and
physical parameters for safe human consumption. Estimates indicate that about
80% of all sicknesses and diseases on a global scale are linked to consumption
of unclean and unsafe water and poor sanitation.
However, the quality of any water is influenced by both
natural and human factors. Without human influences, water quality would be
determined by natural factors and/or processes such as bedrock minerals,
deposition of dust, natural leaching of soil minerals and organic matter, and
biological processes, among others. Water quality is determined by using water
quality guidelines or standards to make a comparison between the physical and
chemical characteristics of water samples. The guidelines and standards are
developed to ensure the safe consumption of water and protection of ecosystems.
Africa with its soaring human population continues to
experience a decline in water quality. Adequate water, sanitation, and hygiene
are essential components for reducing poverty, illness, and death and bring
about an improved socio-economic development. Poor WASH programs expose people
to water-borne diseases, resulting in death and disabilities in certain cases.
The United Nations International Children’s Emergency Fund (UNICEF) report
revealed that the absence of toilets results in the contamination of water
resources, while a lack of clean water impedes on basic hygiene. However, increasing
WASH programs have led to increased access to adequate drinking water sources
and improved sanitation globally since 1990.
To explore how WASH programs could improve the water and
sanitation conditions for poor and developing countries across Africa, it is
important to define hygiene and sanitation. WASH programs are vital for helping
people avoid contaminating water sources, which in turn improves their access
and the overall food safety and security.
WASH programs also help to improve water quality for
adequate food production due to their design nature, whereby communities work
together to disseminate WASH information for a more collaborative program and
implementation. Here, practitioners work together with communities and local
authorities to deliver the components of the WASH program on-site. This is
complemented by practitioners revisiting the communities or distributing
surveys for monitoring and evaluation purpose. Therefore, WASH program
approaches have the potential to improve food security within the poor and
developing African countries.
Effects of water
pollution on food security
Water pollution is the building up of one or more substances
in water to an extent that they cause water-related problems for people and
animals. It is a complex problem that is underpinned by many causes, which
makes it difficult to solve. Increasing human population continues to exert
immense pressure on the world’s water resources. Both urbanization and
industrial revolutions have exacerbated water pollution through effluent and
untreated wastewater discharges.
Irrigated agriculture has resulted in increased salinity of
freshwater bodies as salts are flushed out from soils. When farmers fertilize
their fields or control insects using herbicides, the chemicals used get washed
away as salts through surface run-off into nearby water systems. Toxic
chemicals released into the atmosphere by industries can also enter into water
systems as acid rain.
An increase in water salinity negatively impacts on the
survival of aquatic macroinvertebrates, while some crops become intolerant to
high soil salinities if thresholds are exceeded. As a consequence, soil
productivity is affected and can lead to low crop production and food
insecurity. It is therefore clear that low crop production is not only an issue
in semi-arid regions but also areas that receive plenteous rainfall.
Poor quality of water has a direct impact on food security,
with metals detected in some edible food in China, posing a high health-related
risk to consumers. If pollution effects are properly monitored using the
approaches outlined above, Africa can produce quality food for its citizens.
However, the UNICEF report outlines the importance of educating people on water
quality issues as another approach to solving water pollution.
Further, strict environmental laws are necessary to minimize
water pollution. For example, environmental reports indicate that the “polluter
pays” principle is effective in tackling pollution. The polluter principle
makes it less expensive for humans to behave in an environmental cautious
and/or responsible manner. It is sad, to note, however, that some countries
considered to have the best water laws in Africa and beyond, such as South
Africa, are still struggling to deal with historical water quality issues that
subsequently impact on their food security. Further, unstable countries due to
political reasons such as Libya would greatly be affected by food insecurities
considering their dry nature. The water quality of both countries is discussed
in the following sections.
South Africa: a
country with poor water quality
South Africa has sufficient water to meet all the needs of
the country until the year 2025 and beyond. However, the country is faced with
challenges related to water quality, which impedes on food production to meet
people’s demand for food. Poor water quality renders water unusable. Changes in
agricultural practices and the expansion of urban settlements have a serious effect
on the quality of water. Furthermore, acid mine drainage (AMD), pesticides from
agricultural practices, unmonitored sewerage systems, domestic water usage like
washing clothes on the river and dumping waste in water sources in some areas
of the country, and salinization from the weathering of minerals all pollute
water. Once water is polluted, it may be difficult and extremely expensive to
redress, particularly in the case of underground water, which may affect
agricultural production in terms of excessive salts on the soil and usable
water for food production. It is thus important to note that good water quality
would be suitable for food production to ensure food security.
Libya: a country in a
political crisis
Libya has a rapid growing demand for freshwater availability
while the water supply is limited. The issue of severe water deficits as a
result of nonending water demands in Libya has become more problematic for the
increasing population under low rainfall, which is a result of climate change.
Furthermore, the country has been experiencing high rates of pollution and
depletion due to water resource unavailability. This has had major impacts on
Libya’s economy and social and environmental resistance capacity.
Considering that Libya is one of the driest countries on a
global scale with high temperatures, meeting and maintaining acceptable living
standards for the future is extremely difficult, especially in relation to food
security. Food sufficiency remains uncertain in Libya due to its political
instability coupled with poor water quality and soaring human population. The
country is likely to experience severe and most devastating situations and high
risks of food insecurity and malnutrition with current political instabilities.
Water and food safety
This section discusses the relationship between water and
food safety. Water is seen as an essential component in the food chain,
starting from production, processing, and eventually consumption. In addition,
water pollution has historically impacted on food safety, which constitutes an
important threat to human health, food, and nutritional security. In most
sub-Sahara African countries, food safety problems vary in nature, severity,
and extent. These challenges are often exacerbated by the effect of climate
change and natural disasters such as floods and hurricanes, whereby food may
become contaminated by surface water that has itself been contaminated by
sewage and wastewaters. It is well documented that flood waters often pick up
large quantities of wastes and pathogenic bacteria from farms, sewer systems,
latrines, and septic tanks. Overcrowding of the survivors after disasters may
aggravate the situation, particularly if sanitary conditions are poor.
Any breakdown in vital services, such as water supply or
electricity, also adversely affects the quality of food. In the absence of
electricity, cold storage may be more difficult, if not impossible, and foods
may be subject to bacterial growth. This may be obtained at any stage of the
food chain, from production to consumption. Lack of safe drinking water and
sanitation hampers the hygienic preparation of food and increases the risk of
food contamination.
Food safety has become a constant global concern apart from
affecting human health; factors such as international trade and food security
are also influenced. Consequently, most research institutions, healthcare
institutions, and governments of several African countries have conducted
comprehensive studies on the effect of water on food safety in various
production chains. According to a recent study, the main water issues that
affect food safety in low income countries include bacterial pathogens,
followed by pesticide residues and healthy diet. Although the reported evidence
of food-borne disease is still limited, the known incidences of food borne
disease in low income countries such as sub-Saharan African largely emanate
from three major sources, namely biological hazards and chemical and physical
contamination.
Biological water
contaminants
Water and food contaminated by microorganisms are major
contributing factors for the emerging diarrheal diseases in the developing
countries, and over 1 billion children under the age of 5 years are
affected worldwide. The high prevalence of deaths related to food and water
contamination in developing countries could be attributed to several factors.
For example, in many African countries, milk and dairy production constitute an
important source of livelihoods for most peasant and smallholder farmers.
Furthermore, animal production has become part of agricultural diversification
strategy for most African countries in an attempt to ensure food security. The
intensification of animal production has also generated a considerable impact
on the environment considering the fact that milk provides suitable condition
for the growth of different kinds of microorganisms, and microbial hazards are
the most important concern within the dairy industry.
Biological agents associated with water contamination that
have an impact on food safety include enteric pathogens such as bacteria, viruses,
and protozoa. A study conducted in North-West Province of South Africa reported
that multi-drug resistant Staphylococcus aureus strains were detected
in samples of raw, bulk, and pasteurized milk. Other common biological
contaminants are Escherichia coli. The E. coli bacteria belong
to the intestinal microbiota of humans and animals and are generally not
harmful. Certain E. coli strains, however, harbor virulence factors
and can cause intestinal and extra-intestinal diseases. For example, Shiga toxin-producing Escherichia
coli zoonotic bacteria have globally been associated with various foods of
animal origin, especially beef and sheep meat.
Apart from animal product contamination, biological
contaminants may also occur in crop products. Foodborne outbreaks from fruit
and vegetable produce have caused economic loss, food wastage and loss
confidence regarding the safety of fresh produce from most African countries.
Studies on the safety of fresh produce have identified water as one of the key
risk factors that contribute to contamination of the farm produce. Indeed,
studies have shown that most foodborne diseases are caused by consumption of
fresh, perishable foods sold in informal markets.
Chemical hazards
Generally, mycotoxins, heavy metals, and over-application of
fertilizers and pesticides are considered to be the most important chemical
factors impacting on food safety in most developing countries including the
African region. In nature, thousands of mycotoxins occur but only a few of them
present significant food safety challenges.
Mycotoxins are secondary metabolites mainly produced by
fungal species from the Aspergillus, Penicillium, and Fusarium genera.
They often develop during production, harvest, and storage of grains and nuts
in the presence of water. In the food production process, mycotoxins are among
the most potent mutagenic and carcinogenic substances known. Ingestion of
mycotoxins poses chronic health risks such as hepatotoxicity, genotoxicity,
suppression of immunity, estrogenicity, nephrotoxicity, teratogenicity, and
carcinogenic effects.
The adverse health effects of mycotoxins are compounded by
the fact that they are not completely eliminated during food processing
operations and can contaminate finished processed food products. The presence
of mycotoxins, particularly the aflatoxins, has generated a lot of interest in
the food products from African countries. The work by Maxwell (1998) evaluated
the presence of aflatoxins in human body fluids and tissues in relation to
child health in the tropics. The findings showed that in Ghana, Kenya, Nigeria,
and Sierra Leone, 25% of cord blood samples contained aflatoxins, ranging from
7 ng/L to 65 μg/L. The major classes of aflatoxins that were
identified in the African countries include B1 and M1.
Chemical structures
of aflatoxins prevalent in African countries.
Heavy metals have also contributed negatively to the food
safety status in most African countries. As such, human exposure to heavy
metals in Africa has become a major health risk and has received the attention
of national and international environmentalists. Rapid population growth,
increasing urbanization, and the increasing appearance of slums and townships
as a consequence of poor planning coupled with increasing industrial activities
are some of the major factors that have contributed to the accumulation of
heavy metals in food products. Africa has large deposits of mineral resources,
and mining activities have increased with poor environmental regulations and
compliance. Thus, heavy metals have constituted agents of toxic pollution of
water, air, soil, and food products.
An environmental assessment report by the United Nations
Environment Programme (UNEP) released in 2011, showed that drinking water, air,
and agricultural soil in 10 communities from southeastern Nigeria contained
over 900 times permissible levels of hydrocarbon and heavy metals. The report
further indicated that heavy metal pollution is a continental public health
challenge in the sub-Saharan African region. Another study conducted in the
Democratic Republic of Congo showed a 43-fold increase in the urinary
concentration of cadmium, cobalt, lead, and uranium in human subjects including
children living in mining areas compared to controls.
The increase in the levels of the heavy metals was largely
attributed to ingestion of contaminated food products and water with toxic
chemical compounds. The increasing negative effects on food safety from water
and soil pollution have, therefore, potentially put more people at risk of
carcinogenic diseases, particularly in food producing areas.
Conclusion
Water is the most vital natural resource on the planet that
many life forms depend on for survival. This article has shown how population
growth, competition for water across sectors, and the exposure to infectious
agents or toxic chemicals pose a serious threat to water security, food
security, and human existence. There is increased pressure on all sectors to
minimize water use by considering more efficient use of water and alternative
sources of water.
This is only possible if the normative criteria of the human
right to safe drinking water which are accessibility, availability, and quality
are enforced to ensure that all current and foreseeable water demands
highlighted under SDG 6 are met. Little promising progress has been achieved,
but much work still has to be done to make water sustainability a reality
before the SDG target date of 2030.
The present status of water potential in Africa suggests
that synergies that adopt sharing of expertise, experiences, knowledge,
analytical capabilities, and optimizing mechanisms for greater food safety
assurance and awareness by looking at both chemical and microbial hazards in
foods should be promoted in the continent. #WaterAccess #Sustainability #SDG6
#SDGS #AfricaWaterSolutions #SustainableCommunities
