Physical Characterisation and Analysis of the Perception of Potential Risks Associated with the Proliferation of Solid Waste along the Lomé Coastline in Togo

Abstract

The coastal zone is constantly under pressure from human activities. One of these pressures is the concentration of solid waste that has escaped from the sanitation system in place. The Togolese coastline, mainly the segment from Aflao to Kpogan, is overrun by waste from households and various socioeconomic activities and is faced with the challenges of unregulated solid waste management. This situation is contributing to the degradation of the urban landscape and is giving rise to environmental and health risks. The aim of this study is to carry out a physical characterisation and analyse the perception of the potential environmental and health risks involved. The methodology included documentary research, site mapping, physical characterisation of waste using the MODECOM approach, principal component analysis and a survey of 300 households in our study area. The results show the poor waste management that prevails along the Lomé coastline, with the anarchic proliferation of waste dumps: 13 categories of waste including a predominance of flexible plastic waste out of a total of 510 kg collected. The results show that the environment is deteriorating, with unsightly, unpleasant smells and the presence of pests. These environmental risks expose the population to diseases such as malaria, lung infection, diarrhoea, typhoid fever and skin diseases.

1. Introduction

Globally, coastal areas are very attractive places to live. Situated at the borders between land and sea, coastal zones are among the most densely populated areas on earth. More than 60% of the world’s population now lives in coastal areas, almost 4 billion people living less than 150 km from the coast, and this figure is set to rise to more than 75% by 2035 [1,2,3]. Countries like China and India alone account for 36% of the world’s population. These are regions with high human densities, located on the coasts, along large lakes and in large cities. In America and Europe, the situation is similar, with 22% of the population in America and 15% in Europe living on the coast, and less than 9% in Africa, i.e., less than one inhabitant in ten living 150 km or less from the coastline [4]. Given this demographic growth, these areas are of particular interest to mankind, both for trade and as sources of natural and economic production [4,5,6,7].

With relentless population growth, urban sprawl, the development of economic activities and changing lifestyles, the massive production of waste has become a reality in the world’s cities [5]. This is particularly true of coastal cities, where exposure to human pressures is causing numerous environmental problems [8]. The most recurrent problem is the dumping of solid household waste. Previous studies have shown that more than 10 million tonnes of waste are dumped into the environment every year, 80% of which comes from land and 20% from maritime activities (transport, fishing and aquaculture) [1,9], and a study carried out by the NGO “International Coastal Cleanup” in 2009 on the coastlines of more than 100 countries reveals that almost 60% of waste is attributable to local activities carried out on land, including on the coast [10]. This situation does not spare any part of the globe [11], including African cities [12,13]. Africa, and African cities in particular, are experiencing the highest population growth in the world at 3.58% per year. According to estimates, the urban population will rise from 1.276 billion in 2018 to 2.5 billion in 2050. At the same time, this growth is raising major challenges in several sectors, including waste management. Annual waste production in sub-Saharan Africa is forecast to triple from 174 million tonnes in 2016 to 516 million tonnes in 2050 [14]. Indeed, for most African countries, the waste collection rate remains low, at less than 55%, and the remainder is often dumped illegally in the wild, leading to serious planning and management problems, not only for municipal and central authorities, but also for the population [15,16,17,18].

Following the example of other African countries, Togo, a West African country, has a high population density. The population rose from 6,191,155 in 2010 to 8,095,498 in 2022, and projections predict a population of 9 million in 2027 [19]. Greater Lomé, its capital, is no exception. Thanks to a number of factors, including its geographical location and the development of administrative and economic activities, it is experiencing very rapid demographic growth. In 2010, the population was estimated at 1,507,283, while at the last census in 2022, the city of Greater Lomé had 2,188,376 inhabitants. Population growth projections for the Greater Lomé urban area indicate that it should reach 2,451,900 inhabitants by 2027 [19]. This concentration of population plays a key role in the economic activities located in the coastal zone, particularly agriculture (market gardening), fishing, industry, trade, maritime transport and tourism, all of which contribute to local development. On the other hand, Greater Lomé, which currently has more than two million inhabitants, has not been spared the problems caused by population growth, which has led to the emergence of new neighbourhoods, often lacking essential basic facilities such as drinking water, electricity and sanitation [20]. This situation, combined with inadequate waste collection services and a lack of civic-mindedness on the part of the local population, has led to a poorly organised urban environment, with disreputable management of solid household waste [21]. As a result, we are witnessing the spread of uncontrolled dumps, of which solid waste is the main product. In Greater Lomé, each inhabitant produces an average of 0.6 kg of waste per day and emits 350,340 tonnes of household waste per year (organic waste, plastic, glass, paper, etc.). Of this amount, 89,428 tonnes is collected and landfilled, representing a collection rate of 29.29% [22]. A tiny proportion of the waste collected (9000 tonnes, or 2.95%) is recycled into compost by associations and/or NGOs, and the rest is scattered in the countryside without treatment [22,23]. In view of these shortcomings, household waste management poses enormous problems, despite the efforts made by the authorities to improve the household solid waste management system.

In addition, solid waste management in Greater Lomé has been subject to a multitude of management systems over the years. Initially, solid waste management was the responsibility of the municipality. Later, from the 1970s onwards, waste collection was entrusted to a private company, Société Togolaise d’Enlèvement des Ordures Ménagères et Assainissement (SOTOEMA). It was responsible for door-to-door collection, in refuse bins and by tipper trucks [24]. Then, after the contract was terminated, the authorities signed subcontracts with private operators and associations. One of the many private companies is Ecosysteme Naturel propre (Enpro), set up in 1999. Its aim is to collect, raise awareness of and compost organic waste [25]. In addition, Zoom-Lion, a Chinese company, used to transport waste from intermediate dumps to final landfill sites. Despite these new services, the problem of household waste management remains in the city. With a view to improving solid waste management as a whole, the municipality, with the support of Agence Française de Développement (AFD), launched urban environment projects in 2008, known as PEUL I and II. The aim of these projects is to place all the waste produced in the city in a single circuit. This includes pre-collection or direct collection from households, collection from collection centres, transport and final disposal, while promoting recovery channels [26]. Since 2015, the Agence Nationale de l’Assainissement et de la Salubrité Publique (ANASAP) has been responsible for collecting and transporting waste from intermediate dumps to the final landfill. Finally, in 2018, the local authorities, supported by AFD, provided Greater Lomé with a technical landfill center (CET) in Aképé, 18 km away in the AVE prefecture. This centre will meet the needs of the population in terms of the environment, hygiene and public health, as it will be the waste storage area for the next 20 years [23,27,28]. As a result, the waste collection management system in Greater Lomé has recently been set up. It is organised by the municipality, which manages the entire system as a public–private partnership. This includes the public sector, represented by the local authorities (e.g., commune, prefecture); the private sector, made up of small and large businesses that link the activities of NGOs and the authorities; and finally the informal sector, made up either of individuals grouped together in neighbourhood associations, or of small unofficial businesses dealing either with door-to-door pre-collection, or recyclable materials [22,27]. Unfortunately, the structures put in place to date are struggling to ensure effective management of urban waste. As a result, the pre-collection, collection, sorting and processing system is inadequate, and the city is plagued by insalubrity [20]. Poorly managed, this waste of various kinds (plastic, glass, metal, etc.) is abandoned and ends up on the coast or in the sea, where the bio-ecological conditions are favourable to the development of germs responsible for the diseases to which people are exposed on a daily basis [18]. This study raises the problem of insalubrity along the Greater Lomé coastline, which is characterised by poor management of urban solid waste.

Like other parts of the world, the coastal fringe of Greater Lomé concentrates human, economic and leisure activities. This concentration, combined with demographic growth, is explained by the existence of hotel facilities, fishing camps, bars and restaurants, and industrial and port facilities (Lomé Autonomous Port, the new fishing port, Lomé container Terminal, etc.). It goes without saying that all these activities lead to the production of waste, because the management of waste is limited by the inadequacy of waste disposal infrastructures, the financial means for maintenance and human resources. In addition, the lack of civic-mindedness, the non-application of hygiene rules, the dumping of household waste in the sewage system and the contribution produced by natural factors such as wind, waves and rain encourage the proliferation of waste in the natural environment and, by ricochet, on the Greater Lomé coastline. This study will focus on the natural sedimentation zone made up of the external coastal strips (foreshore), specifically the coastal segment of more than 20 km from Aflao on the Ghana–Togo border to Kpogan on the boundary of the communes of Golfe 6 and Lacs 3. In the western zone, the Ghana–Togo border is dominated by the anarchic occupation of fishing communities and the cross-border population living on the beach. This human presence and the lack of sanitation facilities are at the root of the insalubrity, as is the fact that this sector is bustling with informal commercial and recreational activities on a daily basis, generating waste of all kinds. This waste, when left to its own devices, gives rise to rubbish dumps. Secondly, in the central part of the city, the waste found comes from upstream activities, particularly in the administrative district, Lomé’s largest market and the industrial port complex. This waste is carried by drainage systems and is deposited on the beach or directly in the sea. Added to this is the waste produced by leisure activities (bars, restaurants, picnics). Finally, in the eastern part of the area, bordered by Golf 6 and Lac 3, the concentration of waste is due more to dumping by residents living close to the beach and the lack of collection facilities for cleaning up. In view of these characteristics, the aim of this study is to (i) map the dumping sites that reflect the insalubrity along the coastline, (ii) characterise the physical nature and composition as well as the quantities (weight) of the solid waste collected, (iii) analyse the perceptions of socioeconomic stakeholders, local residents and passing users concerning the potential environmental and health risks along the Greater Lomé coastline.

2. Materials and Methods

2.1. Study Site

This study took place in one of the countries of West Africa, Togo, whose capital is the city of Lomé. It was carried out along a stretch of coastline stretching from the Ghana–Togo border at Aflao in the west and Kpogan at the boundary of the communes of Golfe 6 and Lacs 3 in the east, over a distance of more than 20 km (Figure 1).

The coastline of Greater Lomé is a place of attraction because of its beautiful beaches planted mainly with coconut palms with a multitude of socioeconomic and industrial activities [18,29]. The Autonomous District of Greater Lomé, commonly known as Greater Lomé or the Lomé conurbation, is a special territorial entity with legal personality and financial autonomy. It is the local authority representing the city of Lomé as a whole [30]. It includes natural elements such as the lagoon system and the Atlantic Ocean. It plays an important role in the national economy because of its deep-water port, which covers more than 800 hectares [31,32]. It is an attractive centre for both Togolese and foreigners, with several hotels, bars and open-air restaurants of all categories located on the beach [33]. The town is also experiencing spatial growth in three directions: to the north towards Agoènyivé and Togblékopé, to the north-west towards Adidogomé, Amadahomé, Ségbé, Sagbado and Sanguera, and to the east towards Baguida and Avépozo.

2.2. Data Collection and Analysis

Data collection in the field took place in February 2023. Field trips were made to identify waste concentration points. Next, solid waste was collected for physical characterisation. Finally, direct observations and a questionnaire survey of 300 households were used to analyse perceptions of the potential environmental and health risks involved. All the data collected were subjected to statistical and cartographic processing. The data were processed using Microsoft Excel and Microsoft Word to enter and translate the information gathered in the field into tables and graphs.

2.2.1. Mapping Waste Dumps along the Greater Lomé Coastline

The various field missions carried out enabled GPS point surveys to be taken, which were used to map refuse collection and disposal sites. These were carried out using the LOCUS MAP mobile spatial data collection and management application on a smartphone. A digital camera (Canon Zoom Lens 5x IS 12.1 MP) was used to capture images of waste dumps and the types of waste found in the field. All the data collected in the study area were converted into a shapefile using Google Earth (version 7.3), Qgis (version 3.34.2) and Adobe Illustrator 2019 v23.0.5.625.

2.2.2. Physical Characterisation of Solid Waste along the Greater Lomé Coastline

The physical characterisation for this study was carried out in accordance with the MODECOM (Méthode De Caractérisation des Ordures Ménagères) approach established by the French Environment and Energy Management Agency (ADEME). This method recommends sampling 500 kg of all the waste collected, taking into account the local realities of the area under study [16,34,35]. Adapted according to the MODECOM guidelines, a total of 510 kg of waste was collected and sorted manually according to the steps shown in (Figure 2). Sorting was carried out on a stackable table and quantified using a scale. The main components of municipal waste are listed in 13 categories as suggested by ADEME in the MODECOM in 1993 and included in standard XP X 30 -408 (AFNOR, 1996) [36,37]. The waste collected was sorted manually and separated into 13 categories (green waste, wood, food scraps, paper and cardboard, rigid and flexible plastics, simple textiles, sanitary textiles, metals, glass, unclassified fuels or CNC (made up of wood, leather and rubber), unclassified incombustibles or INC (made up of inert materials such as rubble, gravel, stones, ash and shells), special waste (syringes, blades, batteries) and fine waste). The physical characterisation of the waste provided information on its nature, composition and quantities in order to analyse the distribution of waste and the predominant materials at each site.

The sites were selected using Google Earth and Qgis (version 3.34.2) and Adobe Illustrator on a digital map of Greater Lomé. To sample the waste collection sites, the first step was to digitise the length of the coastline and divide it into strata or segments of 1000 m or 1 km along the coastline. Then, on each 1000-m segment, a 200-m buffer zone was created at regular 2000-m intervals along the entire length of the (Aflao–Kpogan) coastline segment. Six homogeneous sites were selected on this basis. Each site has a surface area of 200,000 m² corresponding to (200 m × 1000 m) for waste collection. Finally, the manually collected waste is stored in coded bags for sorting and weighing in order to determine the quantities of each category. The tools used to characterise the waste included personal protective equipment (gloves, boots, masks), coded bags for each site, a sorting table (measuring 2 m long by 1 m wide), weighing scales (one for masses greater than 5 kg, one for masses less than 5 kg and one precision scale), a notepad and a digital camera (Canon Zoom Lens 5x IS 12.1 MP). All the data collected were analysed and processed using Microsoft Excel to capture and present the information in the form of tables and pie charts.

2.2.3. Surveys and Direct Observations in the Field

This survey was based on data collected in the field and documentary research. The documentary sources consulted refer to books and articles on the degradation of the urban environment, environmental problems, the proliferation of diseases and health problems in urban areas. It focuses on the perception of risk, which can be defined as the judgement of the perceived consequences on the environment or health by an individual, a group of people or a society based on both the characteristics of the hazard and personal beliefs [38]. Risk refers to the existence of factors that may contribute to the emergence and persistence of the source of a hazard or its exposure, the proof of which is not demonstrated through testing. It is understood as a more or less probable danger or inconvenience (immediate or long-term) to which human health is exposed [39,40]. It is to this risk that this study refers [36]. To this end, a questionnaire was administered by random selection to the target groups, taking into account the frequency of their visits and the activities they carry out, mainly socioeconomic players who carry out income-generating activities (formal or informal), local residents living close to the coast and temporary users such as picnickers, etc. Using the KoboCollect application, a digital smartphone questionnaire was used. The questionnaire was based on three headings: identification of each stakeholder, their management practices and their perceptions of environmental and health risks. The present study concentrated on the data collected on potential risks, focusing on two main questions: “What are the environmental risks associated with the presence of solid waste on the coast?” and “What diseases are you most exposed to?” The analysis of potential environmental and health risks was carried out on a total of 300 households. In addition, the ANOVA test was carried out using the respective averages of the statistical data for environmental risks and those for health risks in order to assess the degree of significance of the latter. Direct observations and photographs were used to make the phenomenon under study visible.

3. Results

The results of this study have made it possible to locate waste concentration points, report on the physical composition of the waste and determine the potential environmental and health risks to which people are exposed in the study area.

3.1. Spatial Distribution of Waste Deposits on the Aflao–Kpogan Coastal Strip

Analysis of the cartography shows the locations of the points of waste that characterise the insalubrity along the coast from Aflao to Kpogan (Figure 3). The accumulations of rubbish visible in the western part are due to fishing activity and the anarchic occupation of the populations living on the coast. This area is marked by cross-border traffic between Ghana and Togo, with various commercial activities (bars, restaurants, markets, hotels and other recreational activities) being sources of waste production. In addition, the presence of dwellings with no sanitation or hygiene systems, blocked drains, irregularity and lack of collection services are all factors that encourage the proliferation of solid waste. These characteristics can also be observed in the eastern part of the study area, which is amplified by the lack of civic-mindedness of households living close to the coast. Nevertheless, although there is less rubbish dumping, the central part is marked by dynamic economic activity, characterised by the presence of the largest market in Greater Lomé, Adawlato, also commonly known as “Asigame”, the industrial pottery zone and other related activities, particularly seaside activities, which generate these hidden dumping sites. Over a distance of 20 km, no fewer than 65 waste disposal sites have been identified, an average of 3 sites per kilometre. This situation highlights the visual pollution and shortcomings in waste collection along the Greater Lomé coastline, where human activities are thought to be the main sources of waste production. This is why it is necessary to characterise the waste to determine its typology and the risks to the environment and the population.

3.2. Physical Characterisation of Waste

The characterisation in this study provides information on collection sites, qualitative data on the physical nature and quantitative data for each waste category, as well as on the natural and anthropogenic factors that influence their dispersal, leading to the most dominant categories found on the Greater Lomé coastline.

Figure 4 and

Table 1. Initial and post-characterisation mass of each site.

Batch	GPS Position	Initial Mass Weighed Kg	Mass after Characterization Kg	Error Rate %
S1 (Ghana–Togo border at Kodjoviakopé)	X:301,229.89 Y:676,121.95	85 k	83.8	−1.5
S2 (Opposite the Asigame market in Lomé)	X:305,054.80 Y:677,365.35	86.5	85.7	+0.8
S3 (Ablogamé)	X:308,887.33 Y:678,347.11	85.5	81.1	−2.3
S4 (Katanga)	X:312,374.87 Y:680,269.33	83	84.3	−1.5
S5 (Baguida)	X:316,153.89 Y:681,595.76	85	84.8	−2.0
S6 (Kpogan)	X:319,982.18 Y:682,773.74	85	82.6	−2.8
Total		510	502.3	Average: −1.5

Legend: S = site. Source: the author.

show the location of the sites and the quantities of waste collected at the six sites under study. The total mass of waste collected was 510 kg, of which 502.3 kg was used for characterisation. However, sites 2 and 3 stand out as having the highest weights, at 86.5 kg and 85.5 kg, respectively. This high weight is explained by the production of waste from the commercial activities of Greater Lomé’s largest market, Adawlato (also known as Asigame), on the one hand, and by the concentration of leisure, fishing and port activities on the other. Thus, the heterogeneous composition of the waste found along the Greater Lomé coastline would seem to reflect local eating habits, waste management methods and the heavy presence of human activities.

Figure 5 shows the wastes that dominate all six sites studied. Overall, this study shows five categories of waste to be the most dominant in terms of quantity. Flexible plastic waste unequivocally dominates with a rate of (19.37%) across all sites. This can be explained by the fact that plastic bags are frequently used as packaging for transporting food. In addition, the usual consumption of mineral water packaged in plastic bags costing 25 CFA francs is accessible to all. It is called “pure water”, and because of its affordability and flexibility in transport, it is commonplace among the local population. After use, however, the packaging ends up in the natural environment, drained by the wind or rain and accumulating on the coast. In fact, it is the waste that contributes to the visual pollution of the city’s coastal environment. Fine waste follows with a rate of (19.05%). In addition, wood debris (12.61%) and green waste (11.26%) are present because of fishing activities, the repair of pirogues and the smoking of fish, which predominate in the area, on the one hand, and the discharge of seaweed into the sea and waste from market gardening along the coast, which makes up green waste, on the other. Hard plastics (9.50%) form part of the most common everyday objects in Lomé, particularly utensils. Finally, for the rest, which represents (28.21%), it is not negligible insofar as it interacts in the process of deterioration of the environment and has an impact on human health.

In order to analyse the types of waste that influence each site, (Table 2) provides information on the different categories of waste sorted and their proportions at the sites under study:

-

Site 1 is dominated by green waste and wood (20.6%), followed by hard plastics (19.4%) and CNC (unclassified fuels) (14.5%), while the other categories are less than (10%);

-

Site 2 is dominated by paper and cardboard and flexible plastics, with more than (17%) each, followed by glass waste (16.9%) and CNC (unclassified fuels) (15.2%), while the other categories vary between 0 and 10%;

-

Site 3 is characterised by fine waste representing (23.4%) of the total, accompanied by soft plastic waste (19.7%), while the other categories vary between 0 and 10%;

-

Site 4 is dominated by green waste (19%), flexible plastics (18.4%) and fine waste (17.8%), while the other categories vary between 0 and 10% proportions;

-

Site 5 is characterised by flexible plastic waste (26.5%), followed by wood waste (22.4%) and fine waste (17.7%), while the other proportions range from 1 to 8%;

-

Site 6 is dominated by fine waste (38.2%), followed by flexible plastics (23.9%), while the proportions of the other categories vary between 0 and 8%.

Table 2. Proportions (%) of each waste category per site.

All Fractions	Site 1 %	Site 2 %	Site 3 %	Site 4 %	Site 5 %	Site 6 %
Green waste	20.6	8.2	8	19	8.8	3
Wood	20.6	10.5	5.5	8.3	22.4	8.4
Food	0.2	0.5	3.1	7.7	1.8	3
Paper and cardboard	0	17.6	3.1	1.8	2.1	3
Soft plastics	10.3	17.5	19.7	18.4	26.5	23.9
Hard plastics	19.4	5.3	8	10.1	6.5	7.8
Simple textiles	1.8	1.8	9.9	2.4	2.1	1.2
Sanitary textiles	0	0.2	6.2	0.9	1.2	1.2
Metals	0	0	0.1	1.2	1.8	0.9
Glasses	0	16.9	1.2	2.4	4.1	4.2
CNC (unclassified fuels)	14.5	15.2	6.8	3.6	2.7	3.3
INC (non-combustible ungraded materials)	0	0	3.1	5.	1.2	1.8
Special	1.2	0.6	1.8	0.6	1.2	0.3
Fine < 20 mm	11.5	5.8	23.4	17.8	17.7	38.2
Total	100	100	100	100	100	100

Source: the author.

Table 2. Proportions (%) of each waste category per site.

All Fractions	Site 1 %	Site 2 %	Site 3 %	Site 4 %	Site 5 %	Site 6 %
Green waste	20.6	8.2	8	19	8.8	3
Wood	20.6	10.5	5.5	8.3	22.4	8.4
Food	0.2	0.5	3.1	7.7	1.8	3
Paper and cardboard	0	17.6	3.1	1.8	2.1	3
Soft plastics	10.3	17.5	19.7	18.4	26.5	23.9
Hard plastics	19.4	5.3	8	10.1	6.5	7.8
Simple textiles	1.8	1.8	9.9	2.4	2.1	1.2
Sanitary textiles	0	0.2	6.2	0.9	1.2	1.2
Metals	0	0	0.1	1.2	1.8	0.9
Glasses	0	16.9	1.2	2.4	4.1	4.2
CNC (unclassified fuels)	14.5	15.2	6.8	3.6	2.7	3.3
INC (non-combustible ungraded materials)	0	0	3.1	5.	1.2	1.8
Special	1.2	0.6	1.8	0.6	1.2	0.3
Fine < 20 mm	11.5	5.8	23.4	17.8	17.7	38.2
Total	100	100	100	100	100	100

Source: the author.

3.3. The Greater Lomé Coastline an Environment Threatened by Waste

Waste is an inseparable part of human life, because every action we take generates waste. When it is thrown away or abandoned without proper management, it becomes a threat to the environment and human health. It is important to show the potential risks to which the coastal environment and the approximate living population of the study area are exposed on a daily basis.

The insalubrity observed along the Greater Lomé coastline is caused by human activity. Because it is open to the sea, most human settlements and economic activities are concentrated here, particularly fishing, industry, trade, transport and tourism. It has a large deep-water port covering more than 800 ha of industrial, mining and commercial land, which is renowned for its regional and international traffic. The coastal area alone boasts several hotels of all categories on the beach. The insalubrity of Grand Lomé beach is exacerbated by the inadequate coverage of hygiene and sanitation services. The irregularity of waste collection means that piles of rubbish, often made up of plastic waste, are omnipresent because of their lightness. Moreover, piles of uncollected rubbish putrefy and give off unbearable smells, creating a repellent atmosphere for nature lovers. In addition, due to the lack of toilets, the beach is often used as a comfort station by local residents. Unfortunately, faecal matter is often found along the beach. This inappropriate and unhygienic practice leads to the proliferation of pests (flies, rats, cockroaches, etc.), which disrupt the landscape. Thus, the proliferation of rubbish dumping sites is one of the most recurrent environmental risks along the coast (Figure 6).

The observations made in the field are confirmed by those interviewed, who stated that the unsightliness of the environment, foul smells and the presence of vermin are the main factors in the degradation and pollution of the coastal environment of Greater Lomé. Thus, the opinions differ according to each stakeholder. Of all the socioeconomic players who carry out income-generating activities, 45% say that the concentration of putrefied waste, which emits foul smells, is a major hindrance to their activities, compared with 35% who say that it is unsightly and 20% who mention the presence of pests (rats, birds, flies, etc.). This can be explained by the fact that the piles of rubbish left in the open air are generally located close to their activities, particularly the bars and restaurants on Grand Lomé beach. In addition, temporary users, i.e., those who come to the beach occasionally (at least twice a week), say that foul smells are the most unpleasant for the environment (56%), followed by the presence of vermin (25%) and the unsightliness of the environment (19%). Finally, local residents agree that the piles of rubbish that accumulate along the coast make for an unsightly environment, with (44%) saying this, while (30%) think that this is due to bad smells and (26%) think that the presence of vermin tarnish the coastal environment of Greater Lomé (Figure 7). Olfactory and visual pollution thus characterise the risks incurred on the Greater Lomé coastline. The ANOVA test shows that the p-value is greater than 0.05, so the difference is not significant because all the stakeholders perceive the same effects on the environment.

3.4. Health Risks to Local Populations

Waste scattered around the coast is a source of potential health risks, as the putrefaction of waste gives off unpleasant odours that expose people to the risk of lung infections. In addition, piles of waste that are not dealt with by the sanitation services are breeding grounds for pests such as rats and flies, which are responsible for the transmission of diarrhoeal and gastrointestinal diseases, typhoid fever, and so on [41,42]. In addition, (Figure 8) shows stagnant wastewater sources that are a breeding ground for mosquito larvae and vectors of water-borne diseases such as bilharzia and skin diseases, as evidenced by the work of [18]. Presence of this solid waste on beaches represents a physical hazard for people, particularly children. The risk of injury is likely when sharp or pointed objects (shards of bottles and so on) come from glass waste. As a result, people’s health is vulnerable to the dumping of waste because there is direct communication with the sea. As a result, people’s health is vulnerable to the dumping of waste, as it is in direct contact with the sea, leading to the risk of poisoning fish, which are part of the population’s food chain.

Figure 9 shows that skin diseases linked mainly to bathing water are most affected by temporary users (26%), while suffocation (19%) and lung infections (25%) are felt most by socioeconomic players who practice an activity on site. Choking (19%) and pulmonary infections (25%) are the most common among socioeconomic actors who practice an activity on site. In addition, malaria (37%) and bilharzia (13%) affect more local residents (inhabitants). Finally, diarrhoeal diseases dominate among temporary users and thyroid fever among local residents (10%). The ANOVA test shows that p-value = 0.324, so the difference is not significant for all disease risks.

4. Discussion

Coastal areas around the world, and particularly in the Togolese capital, suffer from insalubrity caused by solid waste. In fact, assessing the state of coastal sanitation by identifying and quantifying solid waste has made it possible to diagnose the state of pollution. This study identified a concentration of waste in 65 open dumps along the Greater Lomé coastline. This insalubrity is thought to be due to the increase in the city’s population, irregular waste collection, lack of civic responsibility and the establishment of economic activities along the coast. This idea is consistent with that of the authors of [18], who show that the proliferation of waste is closely linked to rapid population growth, population behaviour and the inadequacy of waste management infrastructures. This analysis is similar to that carried out in the city of Annaba in Algeria, which states that the main sources of solid coastal waste are residents living near the beaches, domestic and industrial activities, the inadequate sewage system and waste discharged from boats on the high seas, which is transported by the natural elements to the coast [43]. Urban areas are the main source of solid waste [11]. This phenomenon is exacerbated by natural factors such as heavy rainfall and winds, which carry away the waste found on the coast. Similar observations have been made by [10,30,31,32] showing that waste on the coast comes from human activities: 80% of waste comes from the land and 20% from maritime activities (transport, fishing, aquaculture) in coastal areas around the world. This result is consistent with that of [44] on the coastline of the city of Lomé, which observed that sewage discharge from the city of Lomé and human activities along the coast lead to the proliferation of waste in the coastal area.

To this end, the physical characterisation of waste carried out along the Greater Lomé coastline has enabled conclusions to be drawn in qualitative and quantitative terms. This included soft plastics, fine waste, wood waste, green waste, hard plastics, unclassified combustibles (CNC), paper and cardboard, glass, simple textiles, food waste, unclassified incombustibles (INC), sanitary textiles, special waste and metals. These results are similar to work carried out in Mauritania [45] and Togo [36]. However, the present study reveals that the largest quantity of waste is collected in site 2 (86.5 kg), the smallest quantity is found in site 4 (83.0 kg) and the average value for all sites is (85.0 kg). The difference in weight between the sites under study is thought to be due to the density of the surrounding population, their social rank and the similarity of commercial, industrial, port and leisure activities found on the coast, all of which influence waste production. The predominant types of waste at all the sites are soft waste (19.37%), fine waste (19.05%), wood waste (12.61%), green waste (11.26%) and hard plastic (9.51%). The other waste categories account for 28.8%. In fact, soft waste predominates due to natural factors (wind, rain and waves) that encourage its movement and human activities that contribute to its increase through local habits related to food and trade. These results are similar to the study of plastic waste characterization carried out by [46]. In this study, the authors show that Lomé’s three coastal communes (Bè Est, Golfe 4 and Golfe 6) have a high rate of plastic waste (9%, 11% and 9%, respectively), which is thought to be due to human activities along the entire coastline. In the same vein, characterization of 33 households in the city of Lomé during the dry season reveals that plastic waste dominates with 10%, according to the work of [25]. Also, the study carried out on the Israeli coast shows that single-use plastics, plastic bags and cigarette butts are the most common types of waste [47]. This is also supported by the work of [32,38,48,49,50], in Indonesia, [51] in Iran and [52] in Sri Lanka, asserting that plastic waste is the most prevalent in coastal areas and is subject to inefficient management. These trends are also observed in other coastal areas, as shown by studies conducted on the French Mediterranean coastline [53] and in Algeria [54] revealing a strong predominance of plastic materials. On the other hand, wood waste and green waste are significant in the study area due to the influence of fishing activities, the repair of pirogues and the smoking of fish, which are predominant in the area. Green waste is due to the discharge of seaweed from the sea and the market gardening activities that take place along the coastline. Hard plastics are among the most common household materials. As for fine waste, it is relatively dominant as a result of the sand sedimentation phenomenon that prevails along the city’s coastline [44]. However, a study carried out in Algeria [43] more specifically in the town of Annaba, showed a predominance of glass and metals. These results confirm those of [42] stipulating that the distribution of waste in coastal areas is mainly influenced by the human activities responsible for the production of this waste and certain natural factors. These wastes abandoned in nature without adequate management measures pose environmental and health risks. Waste is an imprint on human life and its activities because it is inseparable from them. As a result, it constitutes a risk as soon as its direct or indirect contact with its environment is considered. It is in this sense that [36] approaches risk as the source of the danger or direct or indirect exposure, which is not necessarily demonstrated by chemical or biological tests, but rather by the existence of factors that may contribute to it. It is to these risks that this study will refer. The proliferation of uncontrolled dumping sites and the diverse nature of waste constitute potential environmental and health risks along the Greater Lomé coastline.

This study reveals that the coastline is being denatured by solid waste and wastewater. This wastewater, laden with rubbish, comes from the city’s sewage system and ends up on the beach, or even in the sea. The dumping of rubbish here and there is leading to the deterioration of the living environment and is denaturing the environment. Indeed, the people interviewed during the field surveys stated that the unsightliness of the environment, the nauseating smells and the presence of pests are the main factors degrading the coastal environment of Greater Lomé. These potential risks are not confined to the coastal city of Lomé, as several other African coastal cities are victims of this phenomenon. In the same vein, the waste that washes up on the beach is mostly plastic, which is evidence of human presence and contributes to the unsightliness of the Mediterranean environment due to the slowness with which it degrades [53]. In this regard, the authors Chaouh et al. assert that on the Algerian coast, precisely in the town of Annaba, the dumping of solid waste on the beaches constitutes an eyesore that degrades the beauty of the landscape [29,41]. This degradation has also been observed in the town of San Pedro in the Ivory Coast, where human activities produce waste that is dumped directly into the river due to a lack of collection [55]. This degradation of the coastline is likely to lead to health risks for the population. The results of surveys carried out among the various stakeholders show that people are exposed to a number of diseases, including skin diseases, pulmonary infections, bilharzia, thyroid fever and malaria, which is the most common. This is because the stagnant water mixed with solid waste that occupies a large part of the Greater Lomé coastline is a breeding ground for mosquitoes, which carry the risk of malaria. This is also what has been observed in other studies [43,56] insofar as the proliferation of rubbish dumps and wastewater is closely linked to the proliferation of certain diseases. This is also noted by [57,58] regarding waste management in African cities, suggesting that the inadequacy of waste disposal methods provides ideal conditions for the proliferation of disease vectors such as flies, cockroaches and rodents. And when they come into contact with humans, they transmit infectious diseases to them. Similar observations are found in the city of Bamako in Mali, as [59] showed that there is a correlation between poor hygiene conditions and the occurrence of diseases, of which malaria and ARI are the most recurrent for the populations of the commune of the district of Bamako. They are identical to those of [42] in Anyama in Côte d‘Ivoire. This corroborates the work carried out in the city of Lomé by [18], which provides ample evidence that parasites found in waste can be the cause of many cases of illness recorded in the various health centres, particularly ascariasis, shigellosis, amoebiasis, cholera, etc. Unfortunately, when waste is poorly managed, it provides a favourable environment for pathogens and becomes a source of disease and risk for the population, as well as polluting the soil, air and water, as confirmed by work carried out in Kinshasa by [60].

5. Conclusions

The present work has clearly demonstrated the proliferation of solid waste, which is justified not only by the inadequacy of collection services, but also by incivism and the living conditions of the population. The waste management practised on the Greater Lomé coast shows the shortcomings that exist in terms of planning and organization of coastal environmental management policies. As such, it makes a contribution to the analysis of the spatial occupation of dumpsites through georeferenced data. It will provide a quantitative and qualitative database of coastal waste to optimize the waste management circuit in Greater Lomé, where the quantities of solid waste that are not evacuated have an impact on the living environment and health of surrounding populations. As a result, this study will serve as a decision-making aid and practical guide for developing a solid waste collection circuit. This will facilitate the sorting of waste by category, to serve as an alternative for waste reduction on the Greater Lomé coastline.