Publisher: MDPI, Basel, Switzerland
Title: Urbanization and Environmental Sustainability: Planning Diagnosis of Symbiosis Between Osogbo City and UNESCO World Heritage Site in Osun State, Nigeria
Author: Oyewale Oyeleye and Liora Bigon
Date of Publication: 26 March 2025
Type: Article, open access article
Volume: 14
Citation style language: Not specified in the provided sources
Pollution Type:

• Water pollution: heavy metals (arsenic, copper, lead, chromium, cadmium, mercury), dissolved oxygen (DO), biochemical oxygen demand (BOD), pH

• Air pollution: particulate matter (PM2.5, PM10), carbon dioxide (CO2), carbon monoxide (CO), total volatile organic compounds (TVOC), formaldehyde (HCHO)

• 
  Impact Dimension:

• Environmental: Pollution of Osun River, degradation of air quality, ecological imbalance, environmental degradation, urban sprawl, changes in land use and land cover, threats to urban ecosystems

• Health: Hazardous to human health, kidney problems, carcinogenic effects, increased mortality and morbidity, memory loss, renal dysfunction, cardiovascular problems, vascular endothelia diseases, bone dysfunctions, diarrhea, respiratory disorders, skin cancer, intellectual disabilities, arsenicosis

• Social/Cultural: Affects spiritual purposes during the annual festival, impacts reliance on the river for domestic and irrigation purposes, threatens the cultural heritage site, influences the global cultural festival, relates to Osun River goddess mythology

• Economic: Connected to gold mining activities, influences economic prosperity, impacts tourism industry, trade, hospitality

• 
  Actor Type:

• Authors: Oyewale Oyeleye, Liora Bigon

• Academic Editor: Tao Liu

• Organizations/Agencies: MDPI (Licensee), Ariel University, Osun State University, World Health Organization (WHO), National Environmental Standards and Regulation Enforcement Agency (NESREA), United Nations Educational, Scientific and Cultural Organization (UNESCO), United Nations General Assembly, Urban Alert, National Commission for Museums and Monuments (NCMM), Osogbo’s urban planning agencies (federal: Ministry of Housing and Urban Development; state: Ministry of Lands and Physical Planning, Capital Territory Development Authority, Property Development Corporation; local: Osogbo Town Planning and Land Services, Olorunda Town Planning and Land Services), Osun State Government, Osun State Ministry of Water Resources, Nigerian government (federal, state, local), Osogbo Progressive Forum, Department of Water and Environmental Sanitation (DWES) in Atakunmosa East and West, Federal Ministry of Solid Minerals Development, American Public Health Association, R Core Team

• Individuals/Groups: Tourists, local communities/residents, Osun River goddess’ devotees/adherents, first settlers, virgin lady from royal family, participants of the festival, developers, public

• 
  Response Type:

• Research and Study: Examination of physicochemical properties and heavy metals, assessment of air quality, planning diagnosis, mixed methods data collection, ethnography survey, interviews, statistical data analysis (ANOVA, post-hoc test), proposing future research directions

• Recommendations and Solutions: Measures for future sustainability, pollution mitigation recommendations, policy formulation, adoption of integrated urban water management (IUWM) and total water cycle system, establishment of environmental preservation and protection laws, creation of Osun River Protection and Preservation Agency, proper equipping and staffing of DWES, environmental auditing of miners, enforcement of penalties for offenders, potential withdrawal or suspension of mining licenses, remediation of polluted water bodies, introduction of environmental marshals, discouragement of local fireworks, creation of parking spaces, reconstruction of roads, engagement of adequate urban planning professionals, periodic follow-ups on Environmental Impact Assessment (EIA) reports, harmonization of planning agency operations, collaboration with government agencies, implementation of sanctions and counter-measures

• Traditional Practices: Pouring substances into the river during Osun Osogbo Festival (OOF), carrying appeasement materials

• 
  Evidence Type:

• Water samples analyzed for physicochemical properties (DO, BOD, pH) and heavy metals (arsenic, cadmium, chromium, lead, copper, mercury)

• Air samples analyzed for pollutants (CO2, CO, PM2.5, PM10, TVOC, HCHO) and air quality parameters (temperature, humidity, air quality index)

• Ethnography survey and interviews with gatekeepers (e.g., Director of NCMM, Directors of Osogbo’s planning agencies)

• References to existing literature and previous studies

• Images/figures: Moment from OOF, concentration trend plot of heavy metal pollutants, decade trendline in OOF attendance

• Statistical analysis: One-way ANOVA and post-hoc tests

• 
  Policy Mention:

• World Health Organization (WHO) standards for drinking water quality, air quality, temperature, humidity

• National Environmental Standards and Regulation Enforcement Agency (NESREA) standards for water quality, air quality, temperature, humidity

• United Nations post-2015 New Urban Agenda

• Environmental Kuznets Curve (EKC) theory

• General environmental laws and policies

• Urban planning policies, master plans, development control regulations, physical development plans, urban and regional planning laws (including unimplemented planning bill)

• Creative Commons Attribution (CC BY) license terms

• 
  Key Finding:

• Osun River pollution highest on festival day, followed by pre-festival, then post-festival

• Festival day air quality hazardous: PM2.5, PM10, CO2 exceeded WHO limits

• Osun River water: Arsenic/copper within WHO limits; lead/chromium/cadmium substantially above WHO standards

• Physicochemical characteristics (DO, BOD, pH) generally support aquatic life and human consumption (exceptions: DO post-festival below standards; BOD pre-festival slightly above); pH acidic but permissible

• Festival-day arsenic levels significantly higher than post-festival (linked to substances poured during festival)

• Traditional festival activities did not significantly increase toxic heavy metals (lead, chromium, cadmium) or alter pH vs. non-festival periods

• Temperatures in Osogbo Sacred Grove (OSG) exceeded healthy range, peaking during festival; humidity above WHO standards

• TVOC, HCHO, and CO levels consistently low/non-harmful in OSG

• Osogbo lacks comprehensive physical development plan, enabling pollution/heritage site encroachment

• Planning regulation enforcement hindered by absence of operational planning laws and staff shortages

• Gold mining primary cause of Osun River heavy metal pollution

• Osun Osogbo Festival vital for city development, urbanization, economy; celebrated annually since ~16th century

• 
  Health Risk Projection:

• Untreated Osun River water use unsafe due to lead: Brain damage, memory loss, renal dysfunction, vascular endothelia diseases, death (especially children), intellectual disabilities

• Chromium exposure: Liver damage, skin cancer

• Cadmium exposure: Bone dysfunctions, diarrhea, kidney failure (adults); pathophysiological conditions (children)

• General heavy metal overexposure: Mortality, kidney problems

• Festival-day air pollution (PM2.5/PM10) risks severe respiratory disorders; linked to increased mortality/morbidity during OOF

• Tourists/community members risk renal dysfunction, cardiovascular problems, mental health issues from heavy metals
  URL: https://doi.org/10.3390/land14040707
  DOI: 10.3390/land14040707
  ISBN, ISSN, PMID: These specific identifiers are not provided in the given sources