Today, there is no doubt that the world has increasingly become urban and the 20 century witnessed rapid and unprecedented urbanization of the world's population. The global urban population increased from 13% in 1900 to 29% in 1950, 49% in 2005 and it is estimated that by 2030, 60% of the population will live in the cities. This trend is a reflection of the growth of urban population that increased from 220 million in 1900 to 732 million in 1950 and is expected that there will be 4.9 billion urban dwellers by 2030 (annual urban growth rate of 1.8%). Almost all of this growth will be in lower income regions of Africa and Asia where urban population is likely to triple and in Asia will more than double. Of all the regions of the world, Asia and Africa are urbanizing faster and are projected to become 56% and 64% urban, respectively by 2050. Three countries; Nigeria, India, and China combined are expected to account for 37% of the projected growth of the world population between 2014 and 2050. At the beginning of the 20 century, just 16 cities in the world (mostly in developing nations) contained a million people or more. Today, more than 400 cities have a population of a million or more, about 70% of them are found in developing countries. For the first time in history, in 2007, more people live in cities and towns than will be living in rural areas and by 2017, the developing nation is likely to have become more urban in character than rural. While, there is no universal definition of what constitutes urban settlement, the criteria for classifying an area as urban may be based on one or a combination of characteristics as human population threshold, population density, proportion employed in non-agricultural sectors, presence of infrastructures such as paved roads, electricity, piped water or services, and presence of education and health services. On the other hand, urbanization denotes a process whereby a society changes from a rural to urban way of life or redistribution of populations to urban settlements associated with development and civilization. For millennia, urban areas have been centres and drivers of commercial, scientific, political and cultural life, having a major influence on the whole countries and regions. The Nigerian society is undergoing both demographic transition (people are living longer) and epidemiological transition (change in population health due to changes in lifestyle) mainly as a result of urbanization. The country is undergoing rapid urbanization with a rapidly growing population. At current growth rate of about 2.8%–3% a year, Nigeria's urban population will double in the next two decades.

The pattern, trend, and characteristics of urbanization in Nigeria have been alarming. The towns and cities have grown phenomenally with pace of urbanization in Nigeria showing extraordinary high rates of 5%–10% per annum. Consequently, there has been rapid expansion of Nigerian cities’ area up to 10-fold their initial point of growth and the fact that the growth has been largely unplanned and uncontrolled. Several studies have shown that inadequate planning of urban land uses in Nigeria and great intensity of use has exacerbated urban problems.

In 1995, there were 7 cities with a population of over 1 million, 18 cities with over 500,000 population, 36 with over 200,000, and 78 with over 100,000. By 2020, it is projected that the number of cities with a population of 500,000 and 200,000, respectively will be 36 and 680 assuming annual urban growth rate of 5%. Over the decades, the population of most major cities/towns has increased by many fold. Lagos, Kano, Port Harcourt, Maiduguri, Kaduna, Ilorin, and Jos all had more than 1000% increase over the past 5 decades. For instance, Kano's population rose from 5,810,470 in 1991 to 9,383,682 in 2006. Enugu had 174,000 in 1965, 464,514 in 1991, and 712,291 in 2006 while over the same period; Lagos had a population of less than a million, 4 million, and over 10 million, respectively. Lagos is a mega city where inadequate infrastructure and services, housing shortage, traffic congestion, crime, street violence, and other social vices are well pronounced. These population increases account in part, for the rapid physical expansion of these cities and consequent creation of urban slums and urban villages. In 1950, only 10.1% of population was urban in Nigeria, this rose to 20.0% by 1970, 43.3% in 2000, and it is expected to reach 58.3% by 2020.

1.2Statement of Problem

Urbanization is a major public health challenge of the 21 century as urban populations are rapidly increasing, but basic infrastructures are insufficient and social and economic inequities in urban areas have resulted in significant health inequalities. In this sense, therefore, urbanization in a way is similar to globalization which can be seen as a structural social determinant of health that can challenge the aspirations of equity due to tendency of accumulation of wealth and power among urban elites. Today, most cities in Nigeria have undergone urban decay because of lack of or breakdown in basic services; potable water supply, electricity, efficient city transport services, affordable housing, and waste disposal systems. This is largely as a result of authorities coming to terms with the “tempo” of rising urban needs. These phenomenal transitions are not without health challenges to the population in urban areas and cities. These prompted this review as there is an obvious need to assess how these demographics can enhance our understanding of the current urban trait in Nigeria and its challenges. Urbanization is integrally connected to the three pillars of sustainable development, economic development, social development, and environmental protection, and as urbanization proceeds in Nigeria, the pace and scale of urban population growth will generate important public health challenges for town planners and governments. This is more so since urbanization has not been associated with sustained industrialization and socioeconomic development across the country. Urban poverty and the growth of slums and shanty settlements which are critical challenges to urban health have grown remarkably. Thus, the “health for all will not be achieved for all Nigerians without re-orienting the system to deal with urban health problems.” Systematic search of published literature in English was conducted between 1960 and 2015. Published peer review journals, abstracts, Gray literature (technical reports, government documents, reports, etc.), inaugural lectures, and Internet articles were reviewed. Manual search of reference lists of selected articles was checked for further relevant studies. In this research material, we broadly review the current knowledge on trends of urbanization in Nigeria and health challenges posed by this phenomenon to provide an informed background to stimulate further research and to promote positive urbanization. In addition, health of Nigerians should be a major consideration in both urban renewal and future town planning to ensure that urbanization is not only friendly across all ages but also works to reduce the double burden of infectious and non-communicable diseases (NCDs). Hence, this work seeks to analyse environmental protection agency strategy for reducing health risks in urban areas.

1.3Research Objectives

The general objective of this research work is to analyse environmental protection agency strategy for reducing health risks in urban areas. However, te following specific objectives are formed for the purpose of the research project;

1. To evaluate the roles of the environmental protection agency in reducing health risks in urban areas in Nigeria

2. To assess the performance of environmental protection agency in reducing health risks in urban areas in Nigeria

3. To investigate problems affecting the effectiveness of environmental protection agency in reducing health risks in urban areas in Nigeria

1.4Research Questions

1. What are the roles of the environmental protection agency in reducing health risks in urban areas in Nigeria?

2. What is the level of performance of environmental protection agency in reducing health risks in urban areas in Nigeria?

3. What are the problems affecting the effectiveness of environmental protection agency in reducing health risks in urban areas in Nigeria?

1.6Significance of Study

This research project would be utilized by the government at both federal and state levels through their various ministries like, Ministry of Environment, Education, Health and Information. It will be beneficial ffor these ministries in the area of policy formulation, most especially in the area of educating the public and assisting them in the process of laws formulation to promote human health and protect the environment especially in the urban areas.

The populace will also benefit greatly from this study, as the research project will reveal the environmental protection agencies and their strategies, as well as help the public to be aware of its activities and how their contribution can affect the effectiveness of these strategies. Finally, this work will add to the existing body of knowledge and serve as a reference for future researchers and research work.

1.7Scope of Study

The research project is focused on analysing environmental protection agency strategy for reducing health risks in urban areas in Nigeria. The study intends to investigate the strategies of environmental protection agencies like the FEPA (Federal Environmental Protection Agency), and emphasize the importance of maintaining environmental health practices for sustainability.

1.8Limitations of Study

The major constraints that served as limitations to this work were time constraint, acquisition of materials for the work and financial constraints.

1.9Definition of Terms

Environmental Protection Agency:is an agency of the federal government (FEPA in this case) created for the purpose of protecting human health and the environment by writing and enforcing regulations based on the law.

Environment:refers to the total surrounding of humans that support life.

Environmental Health: refers to the health implications of the interaction between individuals and their natural and built environment.

Urban Area: an urban area is a human settlement with high population density and infrastructure of built environment. They are created through urbanization and are categorized by urban morphology as cities, towns or suburbs.