Africa: Improve both environmental and human health

Afrique : l'environnement fait la santé
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Even though issues such as access to clean water and sanitation affect the health of city dwellers, governments in developing countries do not prioritize environmental concerns. But when governments do address these issues, often with help from the international community, they must find solutions that fit with local needs and customs. Often, both governments and new urban residents require an apprenticeship in healthy urban living.

As the urban population doubles between now and 2030, cities must make room for as many new residents as they currently shelter. This growth poses a real challenge to human health. City dwellers face many poorly-assessed health consequences from air, water and solid waste pollution. Determining environmental pollution's role in health has become vitally important. Just as health is an engine of sustainable development, sustainable development can improve people's health in turn. The infrastructure needed for sustainable urban development has not kept pace with the demographic growth of cities. Furthermore, many African countries lack sufficient economic growth and sound development policies. By concentrating a large number of people in one area, cities increase pollution risks from multiple sources - often without knowing how to assess the risks or protect people from the effects.

This paper will evaluate how cities in developing countries grasp the pollution problem. We will look at two African cities to assess the origins and health impact of pollution. The practices of households in Yaoundé, Cameroon, provide an opportunity to study many sanitation challenges in one city. Ouagadougou, the capital of Burkina Faso, shows how despite many obstacles, some cities pursue more sustainable urbanization by implementing household waste disposal. We will show how highly local solutions are needed more than international plans. We will see that raising people's awareness about pollution and the importance of protecting the environment helps them understand crucial differences between occupying rural and urban spaces. Finally, we will see how this awareness and local participation can support more sustainable development.

Pollution is an Ancient Problem

The banal word "pollution" refers both to activities that degrade the environment and to different types of contaminant: chemical, organic, particulate, etc. While all pollution is noxious, pollution's impact on health remains difficult to assess. Numerous studies, particularly in Western countries, describe air pollution and its health effects (Leikauf 2002; Ly 2007; Theophanides et al. 2007). In developing countries with deficient sanitation, pathogen-contaminated drinking water often causes diarrheal diseases (United Nations 2008; WaterAid 2008). Other pollutants also affect water, nitrates used in fertilizer being a leading contaminant. Accumulation of solid waste - which usually evokes a nasty image of landfills full of slowly rotting, abandoned waste, attracting rodents, insects and birds - has less well-known effects on health. Health problems seen in people living near dumps come less from pollutants' toxicity than from the worry created by foul odours (Lhuilier and Cochin 1999; IAURIF 2007).

Pollution is neither a recent nor an episodic problem. In 400 B.C., Hippocrates linked the intermittent fevers of malaria to certain weather and environmental conditions. However, for much of the pre-modern age, pollution had limited causes and importance. It usually resulted from local surface and ground water contamination by bacterial pathogens and microorganisms in household waste. Only after the Industrial Revolution at the end of the eighteenth century did the human impact on the environment become more noteworthy (Guillerme 2007).

At that time, scientists, industrialists and farmers in what are now developed countries saw the city as a font of natural resources; their new urban projects ensured a certain level of healthfulness, since nothing went to waste. However, once the city ceased supplying those resources, it was no longer able to consume its own waste. The beginning of the twentieth century witnessed a progressive depreciation in the value of urban excrement, which was then called "waste" and "wastewater" (Barles 2005). Europe in the nineteenth century was the theatre of massive cholera and typhoid epidemics that eventually led to great advances in sanitation. John Snow, a British physician who studied the propagation of the 1854 cholera epidemic in London, hypothesized that the city's water supply transmitted the disease.

John Snow publicized his theory in the second edition of an essay "On the Mode of Communication of Cholera" in 1855.

England then launched water treatment facilities to reduce the threat of illness. At the same time, the French chemist and biologist Louis Pasteur discovered the risk of bacterial contamination through human and animal contact, giving rise to an interest in hygiene. These new theories of disease slowly changed the fabric of the city through many different proponents, ranging from the French civic planner Baron Haussmann to the sanitation engineers who devised water treatment and purification techniques (Frioux, 2007; Barraqué 2007). Water supply networks and modern sewage systems were put in place. These improvements, along with medical progress, contributed to a clear improvement in the health of urban populations, which immediately translated into an increase in life expectancy.

Many Risky Sanitary Practicesin Developing Countries

Cities in developing countries bear no resemblance to their developed counterparts: sanitation is insufficient and of poor quality. Solid waste is thrown outdoors with residual water, which can have negative health effects. One-fourth of city dwellers in sub-Saharan African do not have access to sufficiently clean water, and half do not have access to proper sewage facilities (FNUAP 2007). From 1975-2000, only about thirty public wastewater treatment stations were constructed in all of Western and Central Africa (Figure 1). In 2002, these stations represented nearly 20% of the collective waste treatment works in the region. Despite their simplicity, they soon faced reductions in material and financial operations support - quickly exceeding their initial capacity and weakening their output. They have also contended with poor quality monitoring of treated wastewater and effluent.

In Yaoundé, public authorities make considerable efforts to clean up the city, but the results fall short of ever-growing needs. Projects for sanitation systems focus primarily on the city centre and modern neighbourhoods, leaving densely-populated traditional and "spontaneous" or unplanned squatter neighbourhoods untouched. Thus, the enclaves on the valley floors and mountainsides where the poorest people live, areas regularly subject to flood and erosion, have absolutely no storm water management or sanitation systems. To address environmental pollution problems, Cameroon's government passed a law in August 1996

Law number 96/12 of 5 August 1996.

specifying the legal framework for managing the environment across the country. The law accompanied a national environmental management programme; one whose implementation, however, has fallen short because of inadequate financial resources (Ngwé 1999), a multitude of decision centres, and absence of coordination, leading to wasted resources and conflicts over turf.

Sanitary Risks Linked to Types of Sanitation

Developing and developed cities generate large amounts of liquid waste. In Bamako, Mali, the National Direction of Sanitation and Pollution and Nuisance Control estimates household wastewater production at 28.3 litres per inhabitant per day. That is far less than the 118 or 225 litres produced per inhabitant per day in Islamabad and Montreal respectively. In Yaoundé, wastewater disposal volumes are very high and represent 90%-95% of the volume of water consumed, while only 7.3% of Cameroonian households have modern sanitation equipment. Nevertheless, an average consumption of 60 litres of water per day per inhabitant would require daily disposal and treatment of nearly 62,400 cubic metres of wastewater. However, the ten wastewater collection and treatment stations that served 1.2 million people in 2002 are now old and function poorly (Wéthé 2001; Kengné et al. 2001). Indeed, 70% of wastewater, equalling five cubic metres per day and per urban hectare, goes into ground disposal, with a level of pollutants higher than World Health Organization standards. The wastewater is full of suspended solids, up to 2,600 milligrams per litre at the Cité Verte station versus a standard value of 30 mg/l. It also contains high levels of phosphorous (27.9 mg/l versus a standard of less than 1 mg/1), ammonia nitrogen (around 80 mg/l for the Grand Messa and Cité Verte stations versus a standard of 0.5 mg/l), faecal coliform and streptococci (from 103-107 UFC/100 ml), organic matter, and heavy metals such as cadmium, lead and zinc (Nguendo Yongsi 2008; Hien et al. 2008). This leads to fears that pollutants will soon exceed the ground's self-cleaning capacity, increasing groundwater pollution at a time when 65% of residents have no running water and depend on wells and springs. Such situations accentuate faecal exposures that cause diarrheal diseases and account for 13% of infant deaths worldwide. To make up for the government's abandonment of sanitation services, residents turn to independent sewage collection and disposal services, although as we will see, their proliferation also affects urban health.

Risks Vary According to Neighbourhood

A cross-sectional epidemiological study of Yaoundé showed the diarrhoea prevalence rate averaged 14.4% among survey participants. The type of wastewater treatment used in each area determined important disparities between zones (Figure 2).

The IRD (Institut de Recherche pour le Développement), the Pasteur Centre of Cameroon and the University of Paris Ouest La Défense conducted a research programme that aimed to analyse the social and spatial disparities in diarrheic diseases in children less than five years of age in Yaoundé. The survey took place in May 2002 and examined more than 3,000 children in 20 neighbourhoods.

Diarrhoea prevalence rates proved highest where people disposed of sewage directly into the environment; in general, the rate topped out in the so-called spontaneous or unplanned neighbourhoods at 73.2%, and more specifically in spontaneous neighbourhoods around the centre of town at 38.4%. In these types of neighbourhoods, people generally dispose of wastewater via a small drain carved by rainwater that empties into a ditch in the street. These drains are rarely maintained and slalom down hills and between houses, quickly transforming themselves into pools of soapsuds that are sometimes colonised by mosquitoes. By maintaining a certain level of moisture on impermeable soil, this wastewater disposal practice encourages the growth of microorganisms. It is also conducive to certain kinds of nematode eggs that cause diarrheal outbreaks in the city. In planned working-class and modern residential neighbourhoods, the highest diarrhoea prevalence rates occur primarily in households located in minimally-developed areas (sold by the city council through a housing programme, MAETUR),

MAETUR is the Mission to Develop and Equip Urban and Rural Lands

and in recently-moved households not yet connected to the water distribution network.

Such is the case in the Maison Blanche and Ngousso-Yanda neighbourhoods. The highest diarrhoea rates occur in the old, planned working-class neighbourhoods such as Nkomkana, Mballa IV, Minboman III and IV. High rates also occur in central "spontaneous" neighbourhoods such as Mvog Mbi, or those around the centre such as Etoa Meki (Nguendo Yongsi 2009). Wastewater tossed into a courtyard can only, at best, run through channels cut into the dirt by erosion or by the inhabitants. The absence of coordination between many individual actions results in communal harm: everybody tries to make sewage run away from his or her plot of land without paying attention to whether it runs into a neighbour's plot. Health risks are lower where there are slopes that drain more quickly, as in the urbanised edge neighbourhoods of Mballa III or Bilono. On the other hand, health risks rise in low-lying areas where water stagnates in indentations and in smelly black puddles, and where all sorts of potentially disease-spreading insects swarm. High rates of diarrhoea occurring around the fringe of the city centre arise, in part, from human occupancy in these low-lying, swampy areas.

If people have access to clean drinking water drawn from areas far from human habitation, the consequences of poor sanitation systems and wastewater disposal into the immediate environment may prove less serious, at least in the short term. On the other hand, people who live in badly or un-developed urban spaces usually find access to clean drinking water quite difficult. They more often obtain water from poorly-protected, polluted, shallow wells. Individual sanitation systems, based more on do-it-yourself skills than genuine expertise, carry even greater risks than collective systems. That said, diarrheic diseases result from a combination of physical, social and environmental factors within a geographical area. They correlate to environmental disposal of wastewater, but also to population density and education levels of urban residents - people who do not always understand the risks they incur through such non-management of their environment.

Innovative Strategies

Sewer systems may not prove the best solution for developing countries. Building sewer networks would be relatively expensive in many such countries because their cities tend to spread out over large areas. Furthermore, simply building more wastewater treatment stations would not suffice: such stations require maintenance, as do the sewage pipes. The challenge appears even greater given that, at present, some African cities cannot even maintain their simple open gutters. In addition, gutters run randomly in neighbourhoods, without connections to larger-capacity sewage systems. These systems' insufficiencies were particularly conspicuous in Ouagadougou during the record deluge of September 2009, when 260 millimetres of rain - nearly a third of the annual total - fell in one day. All the same, a network of pipes built especially for the sub-Saharan milieu might possibly have reduced the damage to the city centre. The present circumstances call for solutions better-suited to the context, such as individual dry pit latrines, pour-flush latrines, constructed wetlands, and so on.

In nineteenth-century Europe, sanitation infrastructure, like water and electricity networks, depended on subsidies for installation. Cities followed a course of decentralisation in the twentieth century (where responsibility devolved upon local rather than national authorities), using taxes, state and federal subsidies and loans to extend these networks and hook-ups. In developing countries at the beginning of the urban population explosion, such infrastructure was financed by the public sector or semi-public funds. However, structural adjustment programmes and scattered donor funds have led to a drastic reduction in available aid money. Aid funds spent on sanitation sometimes produce the opposite effect of that intended. For instance, sanitation works sometimes have restricted spatial scope or lack coordination with other works, as when gutters are built alongside shortened roads or when they do not form part of an overall urban plan. Furthermore, the simultaneous decentralisation of authorities' responsibilities has made it impossible to raise donor funds. Other solutions need to be explored for financing infrastructure essential to improved living conditions and environmental protection - solutions such as rate-setting, cross-sector subsidies, sharing costs of managing services, drawing on national contributions in the name of solidarity, and so on.

Furthermore, the situation in developing countries today differs greatly from that of Western countries when they first addressed urban environmental issues. In Europe at the time, the urban growth rate was slower since a reduction in both birth and death rates had already taken place. In addition, Western countries had more resources, in contrast to developing countries today, where even water is less available and where it also seems quite difficult to streamline services. Even in Western countries, public hygiene policies were not implemented overnight. They took shape through legal frameworks that initially focused on techniques rather than on an overall system, and that provided a rather limited vision of the urban environment and its concerns. Today, by contrast, one can scarcely imagine environmental improvement and preservation succeeding without community support and participation.

The stated ambitions of the international community, and the investments required to fund that ambition, will not suffice unless local residents recognize the importance of environmental care for ecological and human health. Inertia is certainly a strong force, as seen in the cholera epidemics that strike an increasing number of cities in Africa. Ouagadougou did not escape a cholera epidemic in 2005, despite having won the United Nations prize for environmental efforts at the 2003 Africités congress of African mayors. Although local health authorities stressed the importance of good hygiene habits to protect against faecal contamination, as soon as the epidemic was over, merchants took up their former places along the roads without worrying about dust or poisonous effluvia in the air. Meanwhile, households hit by the disease abandoned efforts to fix up their home plots to ensure better hygiene in the future. However, improvements and progress would only require minimal political, individual and community commitment. The connections between the environment and health have long been well-known, but few research studies exist about the spatial and social disparities in health within cities. The preconception that people live better in cities because of access to schooling, healthcare, equipment and commerce must be reassessed. Simple availability of facilities and services does not guarantee their effectiveness. Other social, economic and cultural barriers in the city can prevent their use (Fournet, Rican and Salem 2006).

Ouagadougou: Obstacles to Implementing Waste Management

The management of household solid waste poses another challenge for African municipalities. They encounter great difficulties in providing waste management services because of rapid and uncontrolled population growth and changes in consumption habits that increase waste volumes. The capital of Burkina Faso, Ouagadougou, attempts to meet the United Nation's international guidelines for environmental preservation through suitable urban policies. Between 1996 and 2006, it underwent population growth estimated at 5.2%, bringing its total population to 1,475,223 inhabitants. Today, the city produces 300,000 tonnes of household solid waste per year. That number may reach 900,000 tonnes in 2020, of which less than half will be treated.

From Burkina Faso's independence in 1960 until the end of the 1980s, a municipal service known as DINASENE

National Directorate of Maintenance, Cleaning and Beautifying Services (Direction Nationale des Services d'Entretien, de Nettoyage et d'Embellissement)

offered a highly centralised solid waste collection system. Sanitation services in Ouagadougou were reorganized in 1986, under the influence of both the international community and the Burkinabe government. During the revolutionary period beginning in 1983, and then under the "rectification" regime since 1987, a "clean city" campaign has combated the accumulation of filth. Urban cleanliness and sanitation became national priorities, while improving the quality of life became a pillar of the government's development programme: its goal was to rebuild neighbourhoods considered unhealthy. Urban Development Projects (UDP) became fundamental tools for implementing waste management policies. Starting in 1986, the Second UDP put seven dumpsters and 115 solid waste cans in place. In 1991, the Third UDP entered the solid waste collection sector by including new participants from the waste management field, thanks to Structural Adjustment Programmes (Arcens 1997; Bayili 2000; Tidiane 2005). In 1996, ONASENE's

National Office of Maintenance, Cleaning and Beautifying Services (Office National des Services d'Entretien, de Nettoyage et d'Embellissement)

breakdown led the government to dissolve it and transfer its responsibilities to municipal technical services as part of an emerging decentralisation policy. The city thus found itself in charge of sanitation, the fight against insalubrity, pollution and nuisances, and the collection and discharge of household solid waste. Private companies perform these services for households on a monthly subscription basis, for rates that vary according to the volume and frequency of collections. The city also launched an ecologically sound solid waste management programme, and wastewater became a priority issue. The city devised a way to improve collecting domestic residues, as well as those from retail shops, workshops and offices, and financed these efforts on the principle of "the polluter pays."

In addition, a National Action Plan for the Environment was adopted as a component of an "Agenda 21"

Agenda 21 is a sustainable-development related programme run by the United Nations.

for Burkina Faso (Meunier-Nikiema 2005). Enacted laws reveal a relatively recent interest in protecting the environment. The first,

Decree Number 98-323.PRES/MEE/MATS/MIHU/MS of 28 July 1998.

from 1998, forbids "keeping or abandoning urban waste in conditions that encourage nuisance animals, insects and other vectors of disease that can harm people or property" (Meunier-Nikiema 2007). In 2005, another law

Law number 022 2005/AN of 24 May 2005.

pertaining to public hygiene introduced terms for pre-collection and controlled discharge in the waste-elimination process. Obligatory waste collection was extended to all neighbourhoods and the city was divided into twelve zones, each assigned to a private collection company that provides "proof of use" receipts to customers. Thirty-five pre-collection centres were built throughout the city. A treatment and waste-recovery centre that combines sorting, recycling, composting and technical burial was set up on the northern edge of the city, near the village of Polesgo.

Waste Collection System Malfunctions

Laws are hard to enforce when a large portion of the population does not understand the link between disease and solid waste thrown into streets. Managing household waste depends on the capacity of companies to satisfy potential demand, peoples' interest in their environment, and their living standards. The 1996 national census

The census was conducted in areas of 1,500-2,000 people, which requires one-and-a-half to two days of work by a census agent.

showed the percentage of heads of households using diverse means of waste disposal: 31.1% used an individual dustbin; 27.8% threw household solid waste onto piles of filth; 13.1% threw solid waste into the street; 11.6% used a solid waste can; 8.3% threw solid waste into pits; and 8.1% used another means (Fournet, Meunier-Nikiema and Salem 2008) (Figure 3). The census results demonstrated a clear difference between habits in central and peripheral districts: in the city centre, the majority used individual dustbins, or solid waste cans provided by the municipality.

The opposite held for the city's periphery. Excepting residential neighbourhoods such as the Zone du Bois in the east or part of the Patte d'Oie neighbourhood in the south, people more or less haphazardly discarded solid waste in public spaces. In neighbourhoods where people with an average standard of living lived alongside people with a lower one, behaviours varied more, as in the Tampouy neighbourhood in the northwest of the city. The exterior ring thus delineated shows a city confined to certain limits in managing waste. Such spaces demonstrate discontent with public services, whether health- or education-related. This situation benefits the relatively scarce private services that residents may be able to afford but whose quality is unproven. Moreover, the lack of pre-collection points throughout Ouagadougou has led informal operators as well as official private companies to illegally discharge household solid waste on reserved city land or empty lots, or else to use wildcat dumps on the city's edge. Improving the waste collection circuit has therefore become urgent, a task that draws on findings presented at various environmental conferences.

Individual Waste Management Behaviours

The first obstacle to constructing a common waste management procedure is its use as a source of organic material for urban agriculture. In Ouagadougou, a portion of the collected household solid waste is discharged onto agricultural land along the urban fringe. However, such waste no longer consists only of biodegradable products. Furthermore, while village residents can do as they like with their private spaces - a Moaga proverb says "The dog is master of his courtyard" - small home plot sizes drive urban dwellers to use public areas for what they cannot do in their own spaces (Déverin-Kouanda 1993). Such behaviours are especially noticeable among new city residents. People born in the city or long-time residents are more sensitive to solid waste collection and cleanliness issues than newly-arrived residents, who maintain rural practices and seem little bothered by waste accumulations. Outside of subdivisions or council lots, housing density does not leave much empty space for use as informal public dumps, in contrast to planned housing areas. Indeed, in such spaces and wherever there are high densities, residents will continue to discard waste outside of their own lots. This may less reflect personal choice than the simple lack of basic city services.

Even if the city makes people think of their environment somewhat differently - because high density and limited space create nuisances linked to household solid waste - old behaviours clearly have not disappeared. For this reason, the government has difficulty exporting new forms of environmental management beyond the largest cities in the country, even as smaller cities face increasing amounts of waste produced by urban living. In developing countries, recent public policies aimed at protecting the environment, improving quality of life and fighting pollution do not stem from the urgency of the public health situation, but rather from global directives coming out of grand international conferences. In any case, one might question whether people in developing countries perceive a link between premature death and pesticide exposure or smoke emissions, given the many forms of social aggression they experience daily. Furthermore, developing countries' public health policies are more often directed toward care than prevention.

The lethal London fog of 1952 played a decisive role in creating public policies to control air pollution, policies later adopted by the other European countries (Logan 1953). It is by no means certain that pollution issues will similarly increase governments' awareness in developing countries. Over the last twenty years, successive health policies in developing countries have focused on primary care. The Bamako Initiative finally created space for the subject of urban health, which had been considered privileged compared to its rural counterpart. These new policies took the shape of creating districts and implementing community participation, cost recovery, vertical and integrated programmes, among other strategies. They did not use any national contexts to frame their structure and were far less interested in prevention than in curative care. According to the French philosopher and physician Georges Canguilhem, health is not an ideal state so much as "the ability to overcome crises" (Canguilhem 2009). One finds two prevalent depictions of health in current policy thinking. In the first model, health appears conceived in terms of illness and the healthcare system becomes the determining element. The second model calls up a vision of public health where social, economic, individual and collective factors play a role. In developing countries, it is always the first model that underpins the conception of health policies.


Most citizens, along with economic, political, social, sports and cultural services and activities, concentrate in cities. To support this activity, cities develop complex relationships with their environment. Theorists have described the notion of "the urban metabolism" (Barles 2005). The description of sanitation in Yaoundé and of waste management in Ouagadougou shows the city is not a unitary system onto which an engineer's management model can be applied. Urban growth management in developing countries can only draw on local solutions adapted to a given society's resources. These solutions range from reducing pollution sources to promoting a better-quality environment. They must take into account that the passage from a rural milieu to an urban one brings changes in perception of space: one moves from an open to a closed space, where the difference between private and public space becomes more important. Urban residents have to learn about this difference. They must not conceive the urban milieu as a natural environment in the biological sense of the term, but as a built one. Consequently, it is up to people living cities to construct a sustainable environment, without seeking to preserve a natural environment that no longer exists. This quest implies and demands that urban dwellers become conscious of their environment, and acquire the will to develop it in the most sustainable way possible.


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