Solid waste generation and disposal are among the pressing public health issues in Nigeria. Solid wastes are useless by-product of human activities which physically contains the same substance that is available in the useful product [1]. It is broadly classified into three types based on its physical attributes. These are liquid, solid and gaseous waste. At the household level, the most common type of waste generated is solid and liquid wastes. Household generation of solid waste has been intricately correlated with changing lifestyle, consumption pattern, population growth, civilization and urbanization among others [2-4]. On the other hand, solid waste disposal is defined as the methods of discarding any product or material which is useless to the producer [1]. In recent times, the rate of solid waste generation within residential neighbourhoods in Delta State of Nigeria have increased with frequent cases of indiscriminate waste disposal.

In the opinion of Oyinloye [5], one of the challenges facing urban settlements in Nigeria is the management of solid waste. The challenge faced by cities in Nigeria is due, in part, to the increasing stream of generated solid waste driven by population growth, industrialization and urbanization as well as the financial burden of waste management and government agents lack of technical capacity to tackle the problem of waste management [6].  Solid waste can be defined as the organic and inorganic used-up materials that encompass both a heterogeneous mass of wastes (domestic) as well as a more homogeneous accumulation of agricultural, industrial and mineral wastes [7]. Solid waste management involves collection, transportation, and processing, recycling or ultimate disposal. The huge increase in solid waste generation from cities and how to dispose of them have caused serious environmental challenges in developing countries like Nigeria. Waste management needs careful planning, if the desired goals are to be achieved. The management of solid wastes, particularly, those wastes generated in urban areas are increasingly becoming complex [8].   Indiscriminate waste disposal leads to the destruction of the aesthetic beauty of the environment, causes flooding and environmental air pollution and sometimes accident [9].

Solid waste management preferences are different from the conventional practices [10]. This is because people generate more solid waste of different components because of their stay at home. The impact of poor solid waste disposal practices and sanitation during pandemics is particularly felt in the Delta State urban areas because people live in proximity to each other. A cursory glance at the city scape reveals that a huge volume of solid wastes are generated daily without adequate form of management. This provokes strong concerns in order to protect the environment and the population from indiscriminate waste disposal. This deplorable and dehumanizing condition of physical environment calls for sober reflections as the coverage of government and private sector efforts to provide these services have remained insufficient [10].

The gory sight of dump sites in several tons in Delta State is very appalling as wastes are dumped indiscriminately along road sides, street corners and drainage gullies designed to help channel water away from the town. This practice is as a result of the failure of the appropriate authority to provide a waste management system that is carefully designed to manage waste in the State.  This has resulted in flooding which has blocked the waterways and gutters during rainy season. This has made it a regular problem and challenge across major towns in the state. This is why this paper examine the methods of solid waste management practices in selected towns in Delta State.            

Literature / Conceptual review

Concept of Solid Waste: Solid wastes is defined as materials of solid or semi-solid character that the possessor no longer considers of sufficient value to retain [11]. Solid waste is everyone‘s problem and is not only confined to less developed neighbourhoods or to developing countries and the poorer nations. Solid waste has, in fact, become such an important part of human ecological footprint, that our very existence is threatened by its contribution to environmental degradation. The leading industrial countries in the world have recognised that continued solid waste generation cannot be offset by improved land filling techniques, but that alternative policies, practices and technologically advanced disposal methods need to be developed and implemented [12].

Solid wastes as an unavoidable part of human activity, comes from either man's production activities or as a by- product of the materials consumed by man. Cities are now grappling with the problems of high volume of solid wastes, the costs involved, the disposal technologies and methodologies, and the impact of solid wastes on the local and global environment [11].According to Urbanbandit [13], Solid wastes is one of those words that are so widely used such that we often forget to question what it really means. Solid waste(s) also known as rubbish, trash, refuse, garbage, junk, and litter, is very subjective; one person may deem an item to be solid wastes whilst another might see it as a resource [14]. Solid wastes are, however, generally regarded as materials that are not prime products (that is products produced for the market), they are materials for which the initial user has no further use in terms of his/her own purposes of production, transformation or consumption, and of which he/she wants to dispose [15].

Management of Solid Waste in Delta State

This practice of indiscriminate dumping of solid waste has the potential of giving rise to water and air pollution, greenhouse gas emission and may give rise to other gases that cause serious problems to the human health and environment [16].  Several waste management practices in the past and present include open dumping, burning, scavenging, separation, recovery, storage, evacuation and recycling. Pivotal to the aforementioned management practices is collection and transportation of solid waste to places where these respective management practices could be enhanced. The transport or movement of solid waste however, could only be effective if solid waste bins are strategically located where they could swiftly and promptly be evacuated. Below are some of the methods of solid waste management practices in Delta State, Nigeria.

Incineration

This is a disposal approach that involves combustion and subsequent conversion of organic solid wastes into gaseous products and residues [17]. Incineration helps to reduce the volume of solid waste by 30% of the original volume. Over the years, large and small scale incineration activities have been carried out at industrial and domestic levels respectively. Certain hazardous solid wastes are usually disposed by incineration. All these notwithstanding, incineration has been the subject of controversial scientific discussion as a result of issues relating to the emission of gaseous pollutants into the atmosphere. This method of solid waste management is most common in nations with small landmass, which makes the construction of large scale landfills difficult [18].

Landfills

Landfill landfilling involves the burying of solid waste in a well designed and constructed landfill. It is the common practice in many developed nations. Landfilling is one of the most hygienic and cheapest methods of solid waste disposal. It could however still have adverse conditions when it starts aging or if the design and construction was poor. Ogwueleka [19] explains that a sanitary landfill has controls in place to collect gases generated, leachate management systems and other mitigations in place to control the impact on the environment and society. Sanitary landfills are an environmentally accepted method of solid waste disposal but are capital intensive at roughly 3-8 times more expensive than open dumping [20]. In Nigeria there are no sanitary landfills [21] although some sites such as Mpape in Abuja have controls in place such as covering solid waste with soil [21]. Sanitary landfills were introduced in Lagos and Onitsha two decades ago, but currently the landfills are not operating [22] because they require much greater initial investment and hence higher operating costs than uncontrolled or open dumps.

The use of Vehicles

An assorted range of vehicles are used for solid waste collection and transfer to disposal sites including trucks, side loaders, rear loaders, mini trucks, tippers, skip trucks and open back trucks [23,19]. Vehicles are often in-short supply or out of service due to frequent breakdown as a result of overuse [24]. For example Ogwueleka [19] observed that 60% percent of trucks available for solid waste collection in Nigeria are in a state of disrepair or out of service at any one time. This has partially led to inadequate service coverage in most urban areas and non-collection in rural areas resulting in improper solid waste disposal. For that reason many scholars have varied solid waste collection rates across Nigeria. Consequently, the management of solid waste has been a primary function of the municipal/ local government in each state; however, attaining efficiency in the sector has been a major challenge especially in the prominent cities within the country such as Owerri, Aba, Enugu, Warri, Port-Harcourt, Kaduna, Lagos and Ibadan where piles of municipal solid waste (MSW) are often observed [25] their sources being households, markets, and places of commercial activity.

Literature / Conceptual review

Concept of Solid Waste: Solid wastes is defined as materials of solid or semi-solid character that the possessor no longer considers of sufficient value to retain [10]. Solid waste is everyone‘s problem and is not only confined to less developed neighbourhoods or to developing countries and the poorer nations. Solid waste has, in fact, become such an important part of human ecological footprint, that our very existence is threatened by its contribution to environmental degradation. The leading industrial countries in the world have recognised that continued solid waste generation cannot be offset by improved land filling techniques, but that alternative policies, practices and technologically advanced disposal methods need to be developed and implemented [10].

Solid wastes as an unavoidable part of human activity, comes from either man's production activities or as a by- product of the materials consumed by man. Cities are now grappling with the problems of high volume of solid wastes, the costs involved, the disposal technologies and methodologies, and the impact of solid wastes on the local and global environment [10].According to Urbanbandit [11], Solid wastes is one of those words that are so widely used such that we often forget to question what it really means. Solid waste(s) also known as rubbish, trash, refuse, garbage, junk, and litter, is very subjective; one person may deem an item to be solid wastes whilst another might see it as a resource [14]. Solid wastes are, however, generally regarded as materials that are not prime products (that is products produced for the market), they are materials for which the initial user has no further use in terms of his/her own purposes of production, transformation or consumption, and of which he/she wants to dispose [14].

Management of Solid Waste in Delta State

This practice of indiscriminate dumping of solid waste has the potential of giving rise to water and air pollution, greenhouse gas emission and may give rise to other gases that cause serious problems to the human health and environment [16].  Several waste management practices in the past and present include open dumping, burning, scavenging, separation, recovery, storage, evacuation and recycling. Pivotal to the aforementioned management practices is collection and transportation of solid waste to places where these respective management practices could be enhanced. The transport or movement of solid waste however, could only be effective if solid waste bins are strategically located where they could swiftly and promptly be evacuated. Below are some of the methods of solid waste management practices in Delta State, Nigeria.

Incineration

This is a disposal approach that involves combustion and subsequent conversion of organic solid wastes into gaseous products and residues [17]. Incineration helps to reduce the volume of solid waste by 30% of the original volume. Over the years, large and small scale incineration activities have been carried out at industrial and domestic levels respectively. Certain hazardous solid wastes are usually disposed by incineration. All these notwithstanding, incineration has been the subject of controversial scientific discussion as a result of issues relating to the emission of gaseous pollutants into the atmosphere. This method of solid waste management is most common in nations with small landmass, which makes the construction of large scale landfills difficult [17].

Landfills

Landfill landfilling involves the burying of solid waste in a well designed and constructed landfill. It is the common practice in many developed nations. Landfilling is one of the most hygienic and cheapest methods of solid waste disposal. It could however still have adverse conditions when it starts aging or if the design and construction was poor. Ogwueleka [19] explains that a sanitary landfill has controls in place to collect gases generated, leachate management systems and other mitigations in place to control the impact on the environment and society. Sanitary landfills are an environmentally accepted method of solid waste disposal but are capital intensive at roughly 3-8 times more expensive than open dumping [19]. In Nigeria there are no sanitary landfills [21] although some sites such as Mpape in Abuja have controls in place such as covering solid waste with soil [21]. Sanitary landfills were introduced in Lagos and Onitsha two decades ago, but currently the landfills are not operating [23] because they require much greater initial investment and hence higher operating costs than uncontrolled or open dumps.

The use of Vehicles

An assorted range of vehicles are used for solid waste collection and transfer to disposal sites including trucks, side loaders, rear loaders, mini trucks, tippers, skip trucks and open back trucks [23,19]. Vehicles are often in-short supply or out of service due to frequent breakdown as a result of overuse [24]. For example Ogwueleka [19] observed that 60% percent of trucks available for solid waste collection in Nigeria are in a state of disrepair or out of service at any one time. This has partially led to inadequate service coverage in most urban areas and non-collection in rural areas resulting in improper solid waste disposal. For that reason many scholars have varied solid waste collection rates across Nigeria. Consequently, the management of solid waste has been a primary function of the municipal/ local government in each state; however, attaining efficiency in the sector has been a major challenge especially in the prominent cities within the country such as Owerri, Aba, Enugu, Warri, Port-Harcourt, Kaduna, Lagos and Ibadan where piles of municipal solid waste (MSW) are often observed [25] their sources being households, markets, and places of commercial activity.

The Health Implications of Solid Waste Management in Delta State

Literature indicates that solid waste management in Delta State is poor, resulting from irregular solid waste collection and indiscriminate disposal of solid waste. Khadafa, Latifa, Abdullahi and Suleiman [26] observed that solid waste is one of the three major environmental problems affecting Nigeria and Delta State, the others being flooding, oil spillage and desertification. The way in which solid waste is managed can have a profound impact on the environment, public health and quality of life [27].  Health and the environment are unquestionably interrelated. Poor air quality, contaminated water, exposure to toxic chemicals and some vector-borne diseases affect ecosystem health as well as human health. A healthy environment is a pre-condition for good public health and health issues are key drivers for concrete action on the environment. 

Globally the most serious environmental problem in terms of solid waste is the emission of greenhouse gases [28]. Greenhouse gases and their effect on the environment has gained the attention of researchers and environmentalists in recent times due to its overwhelming impact in terms of global warming [29]. Dumpsites pollute surface and ground water [15] and they discharge unwanted biological, chemical, and physical solid waste materials into bodies of water causing water pollution. Studies have shown impairments of groundwater quality as a result of leachate generated from dumpsites [30].

The research method adopted is the quantitative method employing the survey approach. Descriptive research was used to describe the impact of solid waste on residents in Delta State through the survey method that was utilized to sample the aggregate opinion of the respondents. The study covered selected towns in Delta State which are reflected in Table: 1

The study used questionnaire to collect primary data as well as secondary data from Delta State Waste Management Board. The instrument was validated by experts in test and measurement and a reliability score of 0.89 indicating that the instrument is reliable and valid.

Table 1: Sample distribution of selected dump sites in Delta State

Source: Fieldwork, 2021

The Pearson’s Product Moment Correlation Coefficient (PPMC), Analysis of Variance (ANOVA) and averages model were used.

Discussion of Results and Findings

Data obtained in Table 2 revealed that 26.4% of the respondents comprise of males while 73.6% of the total population are females. Majority of the respondents comprising of females have better understanding about the environmental and health effects of solid waste management in the study area. Data obtained in the table also revealed that 7.2% of the respondents are between the age of 15-25years, 46% are between the age of 26-35years, 24% are 36-45years and 22.8% are 46years and above. Data obtained shows that 47.2% of the respondents are single, 52.8% are married. This indicates that majority of the respondents are married and comprise of the large household who generates large quantity of solid waste on a daily basis. Therefore, solid waste generation and management problems could be more severe among married couples than the single population in the major towns within Delta State. Data obtained in the table further revealed that majority (33.6%) of the respondents earn ₦101,000-₦200,000 monthly, followed by those who earn ₦31,000-₦50,000 (18.4%), ₦401,000-₦500,000 (17.2%), ₦301,000-₦400,000 (15.6%), ₦501,000 & above (5.6%), ₦51,000-₦100,000 (4.8%), ₦201,000-₦300,000 (3.2%), and less than ₦30,000 (1.6%). This indicates that waste generation and management problems are severe among high income earners who generate large volume/quantity of waste on a daily basis in Delta State. This implies that income level is related to waste generation, the more income one earns, the more waste he/she generates. Lastly, the table showed that 18% of the respondents stay alone (individual), 43.6% live with 2-4 persons per dwelling unit, 26.8% live with 5-7 persons per dwelling unit while more than 8 people live in a dwelling unit. This indicates that the population comprise of large household size who generates large quantity of waste (especially food remnants) on a daily basis resulting to environmental and health issues and solid waste generation/management problems in the study area. The table reveals in all that waste generation is tied to sex (female), marital status (married), income of the individual and family size as determinant factors in the study area.

Table 2: Scio-Demographic Features of Respondents. The Analysis Is Presented Below Beginning with the Socio-Demographic Features of the Respondents

Source: Fieldwork, 2021

Table 3: T-Test Statistics

Source: SPSS Output, 2021

Table 4: Anova

Source: SPSS Output, 2021

Data presented in Table 3, showed that there is significant difference in the method of solid waste collection and waste management practices in Delta State since the t-calculated value (P>4.447) is greater than the t-tabular value of 3.182, therefore H0 is rejected and H1 is accepted. Which that there is significant difference in the method of solid waste collection and waste management practices in Delta State. It was observed that the solid waste methods differ in Sapele (4.443) as compared to other towns in Delta State such as Abraka and Ozoro (4.365), Ughelli and Agbarho (.995), Warri and Jedo (.094), Asaba and Agbor (.609) indicating that solid waste collection and management practices by the Delta State Waste Management Agency differs across major towns and cities in Delta State.

From table 4, the F-calculated value of 2.892 (p>2.892) is significantly greater than F-tabular value of 2.262. Therefore, there is significant variation in the environmental effects of solid waste management on the health of Delta State residents in the different locations.

The result of the analysis obtained further revealed that the t-calculated value (P>4.447) is greater than the T-Tabular value of 3.182 at 0.05 level of significance. The result also showed that the F-calculated value (2.872) is greater than F-Tabular value (2.776) at 0.05 level of confidence indicating that there is significant difference in the method of solid waste collection and waste management practices in Delta State. This is fundamental to understanding the relationship between the environment and the trends of indiscriminate solid waste disposal and thus, their impact on the natural environment as observed Anyakora, et al and Atubi [31]. This is also in line with the findings of Adesanya, et al. [32] who observed that environmental hazards created by pollution has increased the spread of respiratory diseases resulting to the emergence of non-communicable diseases resulting to cases of ill health in Nigerian Cities. This finding also conforms to that of Anyakora, et al who found out that improper waste disposal has serious implication on the natural environment, human health, agricultural productivities, ecological system and social infrastructures. This also conforms with the findings of Anderson [33], Akpovi, Ogbobi [34], and David [35], who found out that the volume of waste generation in Nigerian cities is growing at alarming rate which have adverse effect on the natural environment leading to environmental pollution. 

Policy Implications

Delta State Waste Management Agency should put in place a framework for the management of waste in the State through a collaborative effort. This can be done through a test run of a variety of methods to see the one that most likely work most importantly in the urban areas.  Also, the

Regular monthly sanitation should be strengthened to see to it that waste management practices are maintained not only along the roads but within streets. Delta State Waste Management Officers should take to the task of visiting major towns like the study areas to see how waste management practices are observed. This can be done periodically to make sure that people adhere to waste management practices in their neighborhoods. This way sicknesses and diseases connected to indiscriminate waste disposal will be reduced.

There is no uniform or a systematic pattern employed in the collection and management of solid waste in Delta State. In fact, there are different methods employed across the study areas and these methods showed that they are not in tandem with the management system in the state. Also, solid waste disposal has an effect on the health of residents of Delta State. This is ranging from air to water and food borne diseases that people suffer from as a result of indiscriminate solid waste disposal in Delta State.

1. Amasuomo E. and Baird J. "The concept of solid waste and solid waste management." Journal of Management and Sustainability, vol. 6, no. 4, pp. 88. 2016. DOI: 10.5539/jms.v6n4p88.

2. Afon A.O. "A survey of operational characteristics socioeconomic and health effects of scavenging activity in Lagos Nigeria." DOI: 10.1177/0734242X12444894.

3. Momodu N.S. et al. "Mitigating the impact of solid wastes in urban centres in Nigeria." Journal of Hum Ecol, vol. 34, no. 2, pp. 125-133. 2011.

4. Awoso J.A. et al. "Solid waste disposal and pollution in urban areas a workable remedy for the environment in developing countries." American Journal of Environmental Science, vol. 6, no. 1, pp. 26-32. 2010.

5. Oyinloye M.A. "Using GIS and remote sensing in urban waste disposal and management a focus on Owo L.G.A Ondo State Nigeria." European International Journal of Science and Technology, vol. 2, pp. 2304-9693. 2013.

6. Guerrero L.A. et al. "Solid waste management challenges for cities in developing countries." Waste Management, vol. 33, no. 1, pp. 220-232. 2013.

7. Karsauliya S. "Application of remote sensing and GIS in solid waste management a case study of surroundings of River Yamuna India." International Journal of Environmental Engineering and Management, vol. 4, no. 6, pp. 593-604. 2013.

8. Maity S.K. "Feature extraction from waste generation map by applying squared error algorithm method." Scholars Journal of Engineering and Technology, vol. 2, no. 3, pp. 335-338. 2014.

9. Iro S.I. et al. "Implications of geographic information system in mapping solid waste collection points in Owerri Imo State." An International Journal of Science and Technology Bahir Dar Ethiopia, vol. 1, no. 1, pp. 60-69. 2012.

10. WHO. "Infection prevention and control during health care when COVID-19 is suspected." Retrieved from https://www.who.int/publications-detail/infection-prevention-and-control-during-health-care-when-novel-coronavirus-(ncov)-infection-is-suspected-20200125. 2020

11. Zurbrug C. "Solid waste management in developing countries." Retrieved from http://www.eawag.ch /organisation/abteilungen/sandec/publikationensswm/downloadsswm/basicsofSWM.pdf. Accessed August 2014.

12. Srinivas H. "Solid waste management." http://www.gd rc.org/eum/solid waste. Date accessed March 2021.

13. Urbanbandit W. "What is solid waste?" Zero solid waste advocate and environmentalist, available online at www.urbanbandit.ca, accessed January 3, 2013.

14. Williams P.T. "Solid waste treatment and disposal." 2nd ed., West Sussex England, John Wiley & Sons. 2005.

15. UNEP. "Solid waste management," vol. I. United Nations Environment Programme International Environmental Technology Centre. 2015.

16. Remigios V.M. and Wiseman M. "The management practice and environmental health implications of the municipal solid waste dump site in Alice South Africa." Online Journal of Social Sciences Research, vol. 1, no. 5, pp. 125-131. 2012.

17. Isa M H, et al. "Solid waste collection and recycling in Nibong Tebal Penang Malaysia a case study." Waste Management and Research, vol. 23, no. 6, pp. 565-570. 2005.

18. Fullerton D. and Kinnaman T. "Garbage recycling and illicit burning or dumping." Journal of Environmental Economics and Management, vol. 29, pp. 78-91. 1995.

19. Ogwueleka T.C. "Survey of household solid waste composition and quantities in Abuja Nigeria." Resources Conservation and Recycling, vol. 77, pp. 52-60. 2013.

20. Sridhar M.K.C. and Hammed T.B. "Turning solid waste to wealth in Nigeria an overview." Journal of Human Ecology, vol. 46, no. 2, pp. 195-203. 2014.

21. CPE. "Landfill recovery and use in Nigeria pre-feasibility studies of using LFGE." 2010.

22. Nwosu C. et al. "An assessment of open dumps and landfill management in the Federal Capital Territory Nigeria using Scotland as a case study for structural development." Journal of Environment and Earth Science, vol. 6, no. 7, pp. 78-91. 2016.

23. Abur B.T. et al. "Characterization of municipal solid waste in the Federal Capital Abuja Nigeria." Global Journal of Science Frontier Research, vol. 14, no. 2, pp. 1-6. 2014.

24. Agunwamba J.C. "Analysis of scavengers’ activities and recycling in some cities of Nigeria." Environmental Management, vol. 32, no. 1, pp. 116-127. 2003.

25. Idowu O. et al. "Outsourcing for sustainable solid waste disposal in Lagos Metropolis case study of Agege Local Government Lagos." Journal of Sustainable Development, vol. 4, no. 6, pp. 116-131. 2011.

26. Khadafa A.Y. et al. "Comparative assessment of the municipal solid waste management services." Nature and Science, vol. 11, no. 6, pp. 154-164. 2013.

27. Agbede O.A. and Ajagbe W O. "Solid waste in Southwestern Nigeria." International Journal of Environmental Issues, vol. 2, pp. 92-100. 2004.

28. Ngwuluka N. et al. "Solid waste management in health care establishments in Jos metropolis Nigeria." African Journal of Environmental Science and Technology, vol. 3, no. 12, pp. 459-465. 2009.

29. Achike A.I. and Onoja A.O. "Greenhouse gas emission determinants in Nigeria implications for trade climate change mitigation and adaptation policies." British Journal of Environment and Climate Change, vol. 4, no. 1, pp. 83-94. 2014.

30. 
    Longe E.O. and Enekwechi L O. "Investigation on potential groundwater impacts and influence of local hydrogeology on natural attenuation of leachate at a municipal landfill." International Journal of Environmental Science and Technology, vol. 4, no. 1, pp. 133-140. 2007.

31. Atubi A.O. "The informal sector in solid waste management." Journal of Sustainable Human Development Review, vol. 2, no. 3-4, pp. 5-17. 2011.

32. Adesanya O A et al. "Spermatotoxic impact of Bonny light crude oil (BLCO) ingestion on adult male Swiss albino mice." International Journal of Physical Science, vol. 4, pp. 349-353. 2009.

33. Anderson C.A. "Effect of domestic waste in the environment." James Company London, pp. 43. 2002.

34. Ogbobi K.C. "Scavengers and urban waste enterprises in urban solid waste management in Nigeria the unfulfilled expectation." Journal of Development Studies, vol. 6, no. 2, pp. 87-92. 2010.

35. David M.R. "Designing waste water systems according to local conditions." Published by Brink of F. T city population, Retrieved from http://www.citypopulation.de. 2014.