Particle (Soot) Pollution in Port Harcourt Rivers State, Nigeria—Double Air Pollution Burden? Understanding and Tackling Potential Environmental Public Health Impacts

Abstract

Residents of Port Harcourt in Rivers State, Nigeria, and its environs have since the last quarter of 2016 been experiencing adverse environmental impacts of particle (soot) pollution. This “double air pollution burden”—the unresolved prevailing widespread air pollution and the “added” emergence of particle pollution considered an environmental health threat, led to protests against government inaction in some parts of the state. In February 2017, several months following the onset of the pollution, the government declared an Emergency, and set up a Task Force to investigate and find a solution to the problem. Global research suggests that particle pollution correlates positively with a range of morbidities and an increased risk of mortality among exposed populations. This underscores the need for rigorous implementation of existing environmental legislations established to protect the environment and public health. Nigeria’s rapid response to the 2014–2015 Ebola Virus Disease (EVD) and successful prevention of its spread provides some lessons for addressing such environmental health emergencies—strategic action, including effective environmental risk communication, environmental audit, and monitoring is key. Epidemiological studies of the affected population is imperative. A concerted effort by the Rivers State Ministries of Environment and Health, as well as academia and private organizations is required. Public service campaign in terms of government providing up to date information on the existing situation is required.

Full text

environments
Article
Particle (Soot) Pollution in Port Harcourt Rivers State,
Nigeria—Double Air Pollution Burden?
Understanding and Tackling Potential Environmental
Public Health Impacts
Okhumode H. Yakubu
Department of Public Health Sciences, College of Health and Social Services Building, New Mexico State
University, Las Cruces, NM 88003-8001, USA; ohyakubu@nmsu.edu or hectoryakubu@gmail.com
Received: 23 November 2017; Accepted: 21 December 2017; Published: 24 December 2017
Abstract:
Residents of Port Harcourt in Rivers State, Nigeria, and its environs have since the
last quarter of 2016 been experiencing adverse environmental impacts of particle (soot) pollution.
This “double air pollution burden”—the unresolved prevailing widespread air pollution and the
“added” emergence of particle pollution considered an environmental health threat, led to protests
against government inaction in some parts of the state. In February 2017, several months following
the onset of the pollution, the government declared an Emergency, and set up a Task Force to
investigate and find a solution to the problem. Global research suggests that particle pollution
correlates positively with a range of morbidities and an increased risk of mortality among exposed
populations. This underscores the need for rigorous implementation of existing environmental
legislations established to protect the environment and public health. Nigeria’s rapid response to
the 2014–2015 Ebola Virus Disease (EVD) and successful prevention of its spread provides some
lessons for addressing such environmental health emergencies—strategic action, including effective
environmental risk communication, environmental audit, and monitoring is key. Epidemiological
studies of the affected population is imperative. A concerted effort by the Rivers State Ministries of
Environment and Health, as well as academia and private organizations is required. Public service
campaign in terms of government providing up to date information on the existing situation
is required.
Keywords:
air pollution; criteria air pollutants; double air pollution burden; environmental
impact assessment (EIA); environmental management system (EMS) environmental monitoring;
environmental policy; epidemiological studies; morbidity; mortality; particulate matter (PM); PM
2.5
;
PM10; particle pollution; soot; toxicological studies
1. Introduction
According to the World Health organization (WHO) [
1
], air pollution constitutes the largest
among all of the environmental risks: 3 million annual deaths are associated with outdoor air pollution
exposure. In 2012 alone, 11.6 percent of global deaths equivalent to 6.5 million deaths were outdoor
air pollution-related. 94% of the approximately 90% of air pollution-related deaths occurring in low-
and middle-income countries are as a result of non-communicable diseases, including cardiovascular
diseases (CVDs), chronic obstructive pulmonary disease (COPD), and lung cancer. Industrial activities
constitute a principal source of air pollution [
1
]. Data for Nigeria’s air quality status contained in
the Little Green Data Book 2015 [
2
] puts the population exposed to air pollution at PM
2.5
levels, and
exceeding WHO guidelines, at 94%. This number is above the 72% Sub-Saharan Africa average [
2
].
The poor are further disproportionately affected [3,4].
Environments 2018,5, 2; doi:10.3390/environments5010002 www.mdpi.com/journal/environments

Environments 2018,5, 2 2 of 22
Several studies have not only emphasized the poor air quality in the Niger Delta, including Port
Harcourt, but also the above national and international regulatory-recommended levels of ambient
air pollutants [5–8].
In recent years, studies carried out to assess the levels of criteria air pollutants in cities of Rivers
State, including Port Harcourt, and their probable association with air borne diseases, provide evidence
of correlation. Adoki [
9
] carried out air quality survey in four different locations in Rivers state at
varying distances (60, 100, and 500 m) from emission source. According to his findings, almost
all the samples complied with (Department of Petroleum Resources (DPR)) guidelines for annual
average apart from SO
x
and NO
x
whose annual means exceeded specification at only one location.
Non-conformity occurred mostly in the dry season. During that season, levels of the pollutants
tended to be higher in the evenings and sustained through the early hours of the morning. In all
four locations, suspended particulate matter (SPM) conformed to specification of 230
µ
g/m
3
; with
the highest annual mean being 129
µ
g/m
3
. Like with NO
x
and SO
x
, season significantly influenced
their concentrations [9].
Nwachukwu et al. [
7
] in their survey of a 5-year (2003
−
2007) epidemiological data discovered
that the levels of all the criteria air pollutants in Rivers State was significantly higher than the
WHO specification. They determined that air pollution was associated with air related morbidities
and mortalities in the state. Amongst the air-related morbidity assessed, including cerebrospinal
meningitis (CSM), chronic bronchitis, measles, pertussis, pulmonary tuberculosis, pneumonia, and
upper respiratory tract infection (URTI), pneumonia was the most prevalent for all of the years that
were studied, and was responsible for the highest number (7) of deaths in 2005.
In a study to ascertain the disease prevalence associated with industrial-related air pollution in
specified Niger Delta communities, Godson et al. [
10
] established strong relationships between air
pollutants, including PM with morbidities, such as respiratory diseases, traumatic skin outgrowth, and
child deformities. Their study compared health effects in Eleme, a highly industrialized community
with those observed in Ahoada East, a less industrialized community. Particularly, air pollution
significantly correlated with painful outgrowths (p= 0.027), as well as respiratory health conditions
(p= 0.044). Analysis of data to determine the probable relationship of the use of firewood as domestic
cooking fuel with health outcomes, detected significant association with child deformities (p< 0.0001).
Findings from a different study indicate that adverse health conditions, such as eye and skin disorders,
occurred amongst workers who spent eight hours per day working at facilities with poor air quality
due to ineffective control. For these workers, strong association (p= 0.000) of health disorders
with occupational exposures was established. Additionally, statistical analysis indicated a strong
association (p= 0.000) of number of hours of residence in homes with cancers, deformed children,
health effects that are related to air pollutants, miscarriages or still births, and respiratory diseases [
5
].
A separate study conducted in 2010 further substantiates the health consequences of air pollution in
Port Harcourt—prevalence of lung and skin cancers were found to be higher in Port Harcourt than
in Ibadan [11].
In the recent past months, plumes of soot in the air have affected the residents of Port-Harcourt,
and its environs. According to sources, the first observation was in November 2016 [
12
]. Some affected
residents complained that the government delayed in responding, and only acted when people began
expressing their concerns on social media, and publicly challenging their inaction. [12–14].
This paper highlights the severe consequences of human exposure to particle pollution, and
the need for the implementation and enforcement of existing national environmental regulations.
It proposes translating the lessons learned from positive governmental action in preventing the spread
of the 2014–2015 Ebola Virus Disease (EVD) into air quality issues. The discussion section highlights
the potential health risks of exposed residents by way of the nature, geography, and socioeconomics
of Port-Harcourt. It also suggests the significance of epidemiological studies to determine the health
effects of the pollution to exposed residents.

Environments 2018,5, 2 3 of 22
1.1. The Niger Delta
The oil-rich Nigeria’s Niger Delta is located in the south of the nation and on the delta of “River
Niger”. Niger Delta comprises of nine oil-bearing states namely Abia, Akwa-Ibom, Bayelsa, Cross River,
Delta, Edo, Imo, Ondo, and Rivers (Figure 1), whose lands and waters provide all of Nigeria’s crude oil
supply. Coastal Barrier islands, fresh water swamp forests, lowland rain forests, and mangrove forests
comprise its main ecological zones [
15
,
16
]. considered as one of the most heavily populated regions in
Africa [
17
,
18
], the Niger Delta occupies 70,000 square kilometers of southern Nigeria, and constitutes
the flood plain through which rivers Benue and Niger discharge into the Atlantic Ocean. Essentially, a
network of creeks connecting rivers, rivulets, and streams, including rivers Benin, Bonny, Brass, Cross,
and Nun [16], it serves as a repository of national resource of significant economic value [19].
Environments 2018, 5, 2 3 of 21
1.1. The Niger Delta
The oil-rich Nigeria’s Niger Delta is located in the south of the nation and on the delta of “River
Niger”. Niger Delta comprises of nine oil-bearing states namely Abia, Akwa-Ibom, Bayelsa, Cross
River, Delta, Edo, Imo, Ondo, and Rivers (Figure 1), whose lands and waters provide all of Nigeria’s
crude oil supply. Coastal Barrier islands, fresh water swamp forests, lowland rain forests, and
mangrove forests comprise its main ecological zones [15,16]. considered as one of the most heavily
populated regions in Africa [17,18], the Niger Delta occupies 70,000 square kilometers of southern
Nigeria, and constitutes the flood plain through which rivers Benue and Niger discharge into the
Atlantic Ocean. Essentially, a network of creeks connecting rivers, rivulets, and streams, including
rivers Benin, Bonny, Brass, Cross, and Nun [16], it serves as a repository of national resource of
significant economic value [19].
Figure 1. Map showing soot-polluted areas, Ministry of environment sampling sites, and the location
of sealed companies in Aluu.
Figure 1.
Map showing soot-polluted areas, Ministry of environment sampling sites, and the location
of sealed companies in Aluu.

Environments 2018,5, 2 4 of 22
The Niger Delta sustains Africa’s largest, and the World’s third mangrove forest, bearing not only
Nigeria’s most abundant petroleum resources, but also diversified ecosystems, and numerous aquatic
and terrestrial organisms [
20
–
22
]. However, over the decades, environmental degradation has severely
affected the people of the region, constituting an issue of contention among stakeholders. Despite the
accrued wealth from petroleum, access and condition of social services are low—educational and
healthcare facilities are dilapidated and lacking in basic amenities, with no qualified personnel to
administer minimum basic services. Large numbers of clay-constructed buildings predominate [
22
,
23
],
particularly in the rural areas. Environmental degradation has significantly contributed to the increase
in unavailability of safe drinking water—76–80% in rural areas, and 50–55% in urban areas lack access
to safe drinking water. These conditions explain why indigenes feel marginalized and disadvantaged
in many aspects [22,23].
Customarily, fishing and farming have been the main source of employment, and until date,
account for more than half of the region’s occupation. However, widespread pollution that accumulated
over the years devastated their environment, and consequently their livelihoods [
16
]. GDP per capita
is set at 2400 USD, and poverty is extensive, with an estimated 50% of the 32 million people (22% of
the nation’s total population) living on less than $1.25 per day [
16
]. Thirty percent of the region’s
population is age 30 and younger. Moreover, the region’s characteristic tough geographical terrain
makes the costs of infrastructure rise. Impoverishment is thus not the only issue, underdevelopment
adds to the various problems of the region [22,23].
Furthermore, different communities and ethnic groups have for many years engaged in prolonged
conflicts with one another, the oil companies, law enforcement, and the government, particularly over
their rights including land acquisition and ownership, settlements in form of monetary compensation,
environmental degradation, and deprivation. Although, the number of people that are living in
poverty falls below the national average, in comparison with the rest of the country, on socioeconomic
indicators such as education, environmental quality, and health, its performance is largely lower [
22
,
23
].
Additionally, having one of the highest levels in infant mortality rate, a very vital indicator for general
welfare, it performs poorly. Among youths, levels of underemployment and unemployment are the
highest, set at approximately 40 percent. Youth unrest in the region is attributable to problems arising
from the prevailing substandard environmental, and attendant socioeconomic conditions [22–24].
Despite the serious environmental, economic, socio-political challenges posing significant threat
to the region for over five decades, its oil and gas sector accounts for 95 percent of the country’s export
earnings, and 80 percent of the federal government’s revenue [19,25].
Port Harcourt
Port Harcourt is a metropolitan city [
26
] and capital of Rivers state, occupying approximately
1811.6 km
2
area [
27
], with a population of about 1.5 million [
28
,
29
]. It constitutes the state’s main city
and has one of the largest seaports in the Niger Delta region, thus being the center of administration,
commerce, and industrial activities [
27
]. It is situated between Latitude 4
◦
45
0
N and 4
◦
55
0
N, and
Longitude 6
◦
55
0
E and 7
◦
05
0
E in the state, occupying the entrance of the Bonny river. The city is
bounded in the north by Abia and Imo states; east by Akwa-Ibom state; west by Bayelsa state; and,
south by the Atlantic Ocean. Its estimated mean altitude is 12 km above average sea level, lying
between the Dockyard creek/Bonny River and the Amadi creek [27].
Climatically, Port Harcourt undergoes two distinct seasons viz dry and rainy; nonetheless, the
atmosphere sustains adequate moisture throughout the year. The city’s proximity to the South Atlantic
explains this trend—nearness of inlands to the Atlantic increases annual relative precipitation, thus this
characteristic assures heavy and persistent rainfall, owing to the strong south-west wind. Wind force
reduces as it approaches inland. Mean maximum and minimum temperatures are approximately
34
◦
C and 21
◦
C, respectively—the months of April through October having the highest temperatures.
Like other Nigerian States, the interaction between two major pressures and wind systems drives
the entire weather system in Port Harcourt. They include the two actively produced sub-tropical

Environments 2018,5, 2 5 of 22
high-pressure cells (anticyclones) that are centered over Azores Archipelago (off the west coast of
North Africa) and St. Hellena Islands (off the coast of Namibia). These permanent high-pressure
centers create and run the Northeast trade winds and the South-West winds, respectively, which are
the northward extension of the re-curved Southeast trade winds of the South Atlantic Ocean.
Geographical location and topography of Port Harcourt is such that air borne pollutants travel fast
and the farthest, as high lands are practically absent. Studies suggest that periodic plumes of pollutants
from industrial discharges, a principal source of air pollution, constitutes a frequent occurrence in the
city. Furthermore, occurrence of land breeze, as well as Harmattan, facilitate emission transfer into
the city [27,30–32].
1.2. Double Air Pollution Burden
The current situation suggests a step backward from progress made in the reduction of emissions
by 29%, between 2005 and 2010 [
33
]. The Niger Delta residents have for many decades suffered
the severe exposures of pollution due to various industrial and non-industrial operations and
processes
[9,34]
. To date, they have had to suffer environmental, health, and socioeconomic costs of
the various forms of pollution, including air contamination [
22
,
23
]. Additionally, the current poor air
quality due to soot emission further aggravates the existing poor air quality situation of the region,
suggesting a “double air pollution burden” on population health.
1.3. Prevailing Air Quality Problems
The petroleum industry constitutes a major source of air pollution in the Niger Delta. Within this
industry, production operations, such as oil and condensate spills, gas flaring and venting, as well
as transportation, constitute main sources of pollutants [
35
]. Other sources include power plants,
heavy industry equipment, including boilers, burners, coolants, and separators. Industries such as
foundries, chemical and solvent, automobile, construction, and agriculture also contribute to air quality
impairment in the Niger Delta [36,37].
Gas flaring constitutes a major environmental public health issue in Port Harcourt and other
Niger Delta states. The human health consequences are diverse and include various morbidities and
mortalities [
38
]. Health conditions associated with pollutants discharged in flares include asthma,
cancer of the lungs, difficulties in breathing, miscarriages among pregnant women [
38
–
40
], and
premature deaths [
39
,
40
]. Some gases released from gas flares and other petroleum production-related
activities, and their health consequences are well documented [
10
,
34
,
38
–
41
]. Yakubu [
41
] and Ede [
37
]
document some other pollutants detected in the Niger Delta region and their various health effects.
In their assessment of pollutants originating from automobile in heavy traffic urban areas in
Port-Harcourt, Okonkwo et al. [
42
] demonstrated not only the prevalence of gaseous pollutants, but
also their occurrence at levels exceeding the Federal Ministry of Environment’s I-hour guidelines.
Average concentrations obtained for carbon monoxide (CO), sulphur dioxide (SO
2
), nitrogen oxide
(NO
2
), and hydrocarbons (HC) were above the Federal Environmental Protection Agency (FEPA)
(now FME) standards. Additionally, their study included a comparative analysis of the quantities
obtained at peak periods both in the mornings and in the evenings of each sampling day. Their findings
suggest that the ambient concentration of pollutants at the two sampling sites were in most cases
higher in the mornings between the hours of 8 a.m. and 9 a.m. than in the evenings between 4:30 p.m.
and 5:30 p.m. Although, the differences for the sampling times were not so significant, readings
obtained for Monday through Saturday were much higher than those that were obtained for Sunday,
during which time less industrial activities and traffic occur.
Ede et al. [
37
] analyzed air samples obtained from 16 communities in the Niger Delta including
Port-Harcourt for their CO, SO
2
, NO
2
, HC, and suspended particulate matter (SPM) composition.
In most cases, the quantities of pollutants exceeded the WHO Air Quality Guidelines. In particular,
the particulate load was above the WHO specification for both PM
2.5
and PM
10
annual mean and 24-h
mean (PM
2.5
: 10
µ
g/m
3
annual mean, 25
µ
g/m
3
24-h mean; PM
10
: 20
µ
g/m
3
annual mean, 50
µ
g/m
3

Environments 2018,5, 2 6 of 22
24-h mean). Although, the value range obtained for each pollutant was dependent on the time of
the day and year or season; nearness to point source; and extent of anthropological engagement.
Amongst the 16 locations, Port-Harcourt had the highest mean SPM load. Association of high SPM
loads with such factors as high numbers of oil fields and gas flare sources; ongoing construction
activities, location on or proximity to highly engaged roads, and industrial facilities occurred [37].
In 2014, Weli [
43
] conducted an extensive research involving in-depth quantitative analysis of
the spatial and seasonal atmospheric levels of PM
10
in Port Harcourt, and the environmental health
implication of their occurrence at measured concentrations. Relative quantities of the pollutant in
various areas based on land use, and the time of the year were compared with land use, including
commercial, high-density residential, low-density residential, industrial, and rural. PM
10
sampling
and analysis was conducted in the dry, transition, and wet seasons. Findings suggest that land use and
season influenced atmospheric concentrations of PM
10
. For all land use type, the trend in the seasonal
levels of PM
10
was dry > transition > wet. In terms of land use, the commercial and industrial areas
had the highest values in the dry season. The Low-density residential areas had the lowest PM
10
value.
The seasonal total atmospheric loading for the wet, transition, and dry seasons were 3436.1
µ
g/m
3
,
8573.12
µ
g/m
3
, and 16,148.87
µ
g/m
3
. The study also suggests a statistical significant difference in
the seasonal PM
10
concentration amongst the land use types. People who live and work around the
areas with a high concentration of PM are susceptible to respiratory disease infection. This includes
high-density residential areas.
In its five years period (2008–2013), assessment of air levels of particle pollution (PM
2.5
and
PM
10
), the WHO selected 765 cities from 67 countries. Results from this assessment suggest that
among cities with a population exceeding 100,000 inhabitants, four major Nigerian cities, namely Aba,
Kaduna, Onitsha, and Umuahia constitute 20 of the most polluted cities in the world, in terms of
annual mean concentration of PM
10
(Air pollution levels rising in many of the world’s poorest cities)
(Figure 2). Among these, Onitsha ranks the worst polluted with a record 30 times higher than the WHO
stipulations. The WHO specifies a 20
µ
g/m
3
annual mean. Aba and Onitsha form part of Nigeria’s
manufacturing center [
4
,
44
,
45
], and are states in the Nigeria’s Niger Delta. Kaduna, Aba, and Umuahia
showed a 21, 19, and 18 times more annual mean average of PM10 than WHO limits, respectively.
Environments 2018, 5, 2 6 of 21
day and year or season; nearness to point source; and extent of anthropological engagement.
Amongst the 16 locations, Port-Harcourt had the highest mean SPM load. Association of high SPM
loads with such factors as high numbers of oil fields and gas flare sources; ongoing construction
activities, location on or proximity to highly engaged roads, and industrial facilities occurred [37]
In 2014, Weli [43] conducted an extensive research involving in-depth quantitative analysis of
the spatial and seasonal atmospheric levels of PM
10
in Port Harcourt, and the environmental health
implication of their occurrence at measured concentrations. Relative quantities of the pollutant in
various areas based on land use, and the time of the year were compared with land use, including
commercial, high-density residential, low-density residential, industrial, and rural. PM
10
sampling
and analysis was conducted in the dry, transition, and wet seasons. Findings suggest that land use
and season influenced atmospheric concentrations of PM
10
. For all land use type, the trend in the
seasonal levels of PM
10
was dry > transition > wet. In terms of land use, the commercial and industrial
areas had the highest values in the dry season. The Low-density residential areas had the lowest PM
10
value. The seasonal total atmospheric loading for the wet, transition, and dry seasons were 3436.1
μg/m
3
, 8573.12 μg/m
3
,
,
and 16,148.87 μg/m
3
. The study also suggests a statistical significant difference
in the seasonal PM
10
concentration amongst the land use types. People who live and work around the
areas with a high concentration of PM are susceptible to respiratory disease infection. This includes
high-density residential areas.
In its five years period (2008–2013), assessment of air levels of particle pollution (PM
2.5
and PM
10
),
the WHO selected 765 cities from 67 countries. Results from this assessment suggest that among cities
with a population exceeding 100,000 inhabitants, four major Nigerian cities, namely Aba, Kaduna,
Onitsha, and Umuahia constitute 20 of the most polluted cities in the world, in terms of annual mean
concentration of PM
10
(Air pollution levels rising in many of the world’s poorest cities) (Figure 2).
Among these, Onitsha ranks the worst polluted with a record 30 times higher than the WHO
stipulations. The WHO specifies a 20 μg/m
3
annual mean. Aba and Onitsha form part of Nigeria’s
manufacturing center [4,44,45], and are states in the Nigeria’s Niger Delta. Kaduna, Aba, and
Umuahia showed a 21, 19, and 18 times more annual mean average of PM
10
than WHO limits,
respectively.
Figure 2. World Health organization (WHO) Urban Ambient Air Pollution Data Base 2016 Update
(data only).
2. Criteria Air Pollutants—The United States Environmental Protection Agency (EPA)
The criteria air pollutants are those commonly present in outdoor air, originate from multiple
sources, and are harmful to environmental public health. They can also result in property damage.
Figure 2.
World Health organization (WHO) Urban Ambient Air Pollution Data Base 2016 Update
(data only).

Environments 2018,5, 2 7 of 22
2. Criteria Air Pollutants—The United States Environmental Protection Agency (EPA)
The criteria air pollutants are those commonly present in outdoor air, originate from multiple
sources, and are harmful to environmental public health. They can also result in property damage.
They include carbon monoxide (CO), ground level ozone (O
3
), lead (Pb), nitrogen dioxide (NO
2
),
particulate matter (PM), and sulphur dioxide (SO
2
) [
46
]. The US Federal Clean Air Act (CAA) institutes
the regulatory structure for the control of air contaminants. Section 108 of the CAA mandates the
EPA to set up National Ambient Air Quality Standards (NAAQS) for criteria air pollutants for the
protection of the environment and public health. Provisions of the CAA include the monitoring of
their ambient concentrations [46].
3. Seriousness of the Problem
3.1. Public Health Impacts
The EPA defines PM
10
as inhalable tiny fragments, with diameters that are commonly
10 micrometers and less (aerodynamic diameter
≤
10
µ
m (PM
10
)) or the thoracic fraction; and PM
2.5
as fine inhalable tiny flecks, with diameters that are mostly 2.5 micrometers and tinier (aerodynamic
diameter
≤
2.5
µ
m (PM
2.5
)). Coarse PM fraction (aerodynamic diameter between 10
µ
m and 2.5
µ
m
(PM
10–2.5
)) or only one size fraction also exits. The particle size of soot is approximately 2.5 microns, a
type of particle pollution that is associated with deep lung penetration [
47
,
48
]. Fine particulate fraction
is the leading cause of global pollution-related mortality [
49
,
50
]. Particles that are approximately
10 microns (PM
10
) or larger are usually trapped in the upper respiratory tract, and prevented from
penetrating deep into the respiratory tract. Particles 5 microns or smaller can make it down to the
lower lung where the gas exchange occurs in the alveoli. The largest PM
2.5
fragment is 30 times smaller
than the average human hair, which is approximately 70 micrometers in diameter [
51
]. Soot penetrates
deep down in the lungs, imparting a wide range of serious health outcomes, including acute bronchitis
and aggravated asthma among children, heart attacks, and strokes, as well as premature death [
52
].
Further, the American Lung Association [
53
] suggests that inhaling soot can potentially cause “cancer
as well as developmental and reproductive disorders”.
3.2. Carcinogenicity of Soot and Other Particle Pollution
The routes of entry into the human body include ambient and indoor air inhalation, ingestion
of contaminated food, and dermal contact. Based on sufficient evidence from human carcinogenicity
studies, soot causes cancers in humans [
54
]. In 1775, British surgeon Percivall Pott established a
correlation between scrotal cancer and exposed chimney sweeps. In subsequent years, substantial
amounts of epidemiological studies have since confirmed the elevated risk of scrotal and other skin
cancers among chimney sweeps [
55
]. Similarly, research establishes strong association between
occupational exposure (chimney sweeps) and increased mortality from lung cancer, in a number of
European countries. In a separate study, leukemia and cancer of the esophagus, as well as risks of liver
cancer correlated with exposure to soot [
47
,
56
]. Correspondingly, follow-up studies among Swedish
chimney sweeps revealed that risks for esophageal, hematopoietic, prostate, urinary bladder, and total
lymphatic cancer were elevated [57].
3.3. High Risk Populations
Soot can have adverse health consequences on population health, however, babies and children
(particularly due to their premature respiratory organs [
3
]), the elderly, and people with preexisting
health conditions, including heart or lung diseases (such as asthma) are more vulnerable [
56
]. Like other
particle pollution, soot is associated with difficulty in breathing; eye, lung, and throat irritation; birth
related problems, such as low birth weight; and, heart disease [56].

Environments 2018,5, 2 8 of 22
3.3.1. Preexisting Diseases
According to the EPA [
46
], preexisting health conditions including cardiopulmonary diseases
and diabetes may increase susceptibility to PM health effects among exposed human populations.
Recent epidemiological and experimental studies demonstrating association between PM exposures
and morbidity and mortality among human populations, substantiates this argument [58–63].
Cardiovascular Disease (CVD)
Peel et al. [
58
] discovered that patients with preexisting hypertension when exposed to PM
10
experienced an increased risk of emergency department visits for dysrhythmias and congestive heart
failure (CHF). Toxicological studies carried out on rat models of hypertension by Sun et al. [
59
] provide
support for results obtained by Peel et al. [
58
]—PM
2.5
concentrated ambient particle (CAP) exposure
led to increased mean arterial pressure when compared with air controls. This outcome establishes the
association between exacerbation of hypertension-related CVD and PM2.5.
Coronary Artery Disease (CAD)
Park et al. [60] conducted a panel study in Boston to examine preexisting cardiovascular-related
CAD on PM-related cardiovascular effects. Their findings suggest that patients with preexisting
ischemic heart disease (IHD) suffered more significant heart rate variability (HRV) than those without
IHD on exposure to PM
2.5
. Several animal studies carried out following this finding suggest similar
outcomes [61,62].
Congestive Heart Failure (CHF)
A number of epidemiological studies examined the probable alteration in PM-related
cardiovascular effects by comparing two groups (with and without preexisting CHF) of individuals at
different locations. One study discovered that short-term exposure to PM
2.5
correlated with increased
risk of hospital admissions for events related to acute IHD among individuals with preexisting CHF [
63
].
Similarly, a different study carried out in Cook County, Illinois, indicated a greater risk of mortality
associated with PM exposure among those with preexisting CHF than individuals without [64].
3.3.2. Respiratory Disease
Chronic Obstructive Pulmonary Disease (COPD)
Epidemiological studies on the effect of PM on lung function demonstrated that in response to
PM
2.5
exposures, higher declines in pressured expiratory volume per second and forced vital capacity
were recorded for patients with, than for those without COPD [
65
,
66
]. Other studies [
67
,
68
] also
suggest that COPD increases the potential risk of PM-related health effects.
Asthma
Several epidemiological studies have established the association of PM exposure with exacerbated
asthma symptoms. Short-term PM
2.5
exposure among children with asthma had a correlation with
breathing symptoms, such as cough, gasping, and tightness in chest [
69
], as well as increased
medication use [
70
]. Although, limited evidence exists on the health effects of PM exposure in
adults with preexisting asthma, Desqueyroux et al. [
71
] observed an association of short-term PM
10
exposure with asthma attacks. Additionally, when compared with nonasthmatics, in a controlled
human exposure study, asthmatics showed acute responses in the cardiovascular system and systemic
circulation following PM2.5 CAPs exposure [72].

Environments 2018,5, 2 9 of 22
3.3.3. Children and Older Adults
Among children, elevated PM dose per unit surface area of the lungs, and the consequent adverse
effects on growing lungs, are a result of greater activity levels, outdoor duration, as well as volume per
unit body weight. Epidemiological studies of short-term PM exposure suggest increased respiratory
health effects, including cough, respiratory hospital admissions, and wheeze among children less than
18 years of age when compared with adults [
73
,
74
]. A collection of toxicological studies demonstrates
that exposure to PM during the critical stages of development may hamper the maturation of the
respiratory system in terms of structure and function [75,76].
According to Sacks et al. [
77
], when compared with children and younger adults, older adults
constitute a probable vulnerable population to the health effects of air pollutants, including PM due to
the higher prevalence of preexisting cardiovascular and respiratory conditions, which may aggravate
susceptibility to PM. Several epidemiological studies on PM
2.5
[
78
], PM
10–2.5
[
73
], and PM
10
[
79
]
exposures indicate increased risk of cardiovascular disease (CVD) hospital admissions among older
adults when compared to all ages below 65. Correspondingly, some studies [
80
] indicate correlation
between PM exposures with respiratory diseases in older adults. Controlled epidemiological studies of
human exposures to PM
2.5
concentrated ambience among older adults indicated decreased heart rate
variability (HRV) with or without accompanying COPD [
81
,
82
]. Furthermore, some epidemiological
studies have shown an association of short-term PM
2.5
[
83
] and PM
10
[
84
,
85
] exposure among older
adults
≥
75 years, with the progression of health effects from early stages to cardiovascular-related
hospitalization or respiratory-related hospitalization and eventual non-accidental death. These studies
show that this age group are more susceptible when compared with younger ages that is
≤
75 years.
Naess et al. [85] made similar observations for long-term PM2.5 exposures.
3.3.4. Socioeconomic Status (SES)
Research suggests that low SES correlates with higher prevalence of preexisting health conditions.
A study by Dutton and Levine [
86
] revealed that socioeconomic status (SES), including income
level, social status estimated by educational attainment, and work status evaluated based on type
of occupation, could have an influence on susceptibility of a population to PM-related health effects.
According to Kan et al. [
87
], restricted medical care and access to healthy foods are directly proportional
to increased susceptibility of the health effects of PM.
Franklin et al. [
83
] in their epidemiological studies estimated low SES based on median household
income (i.e., those living below poverty level) and found a correlation with an increased risk of
mortality for short-term exposure to PM
2.5
. Likewise, Jerrett et al. [
88
] established a correlation of
residential environment with a greater mortality rate for exposure to PM
2.5
on a short-term basis.
Other studies established a coherent trend of increased mortality correlation with human exposures
to PM
2.5
, and PM
10–2.5
for low educational attainment groups (
≤
high school diploma) [
89
–
91
].
Additionally, several studies demonstrate that residential location or environment significantly
correlates with greater mortality risks for short-term PM
2.5
exposures, based on studies carried out in
Hamilton Canada and in Phoenix, Arizona [92].
3.4. Environmental Consequences
Haze of soot has since covered most parts of Port Harcourt city [
93
]. Visibility impairment
by PM
2.5
, soil, and water deposition, resulting in a change of chemical composition of the affected
media and staining of materials, are some of the environmental consequences. The overall result
includes more acidic lakes and streams; alterations in nutrient equilibrium in rivers and coastal waters;
soil nutrient depletion; and, disruption in ecosystem diversity. Particle pollution also contributes
significantly to the impact of acid rain [52].

Environments 2018,5, 2 10 of 22
3.5. Socioeconomic Costs
In consideration of the serious environmental conditions, some parents out of fear restrained their
children from playing outside [
94
]. Residents spend most of their time indoors rather than outdoors.
According to The Guardian [
94
], some residents in various cities, such as Rumosi and Rumuodumanya
(Figure 1), both in Obio/Akpor Council abandoned their homes to other cities that they considered
safe. The effect of this movement is a decline in business activities with an anticipated cost on the
economy of Rivers State as whole.
4. Stakeholders’ Reaction
4.1. Public Response
Port-Harcourt residents, including prominent Nigerians, in February 2017, protested the increased
deterioration of ambient air quality. Complaints that were made included black soot settling on cars,
floors, roofs, and household furniture surfaces. Furthermore, frequent cleaning off a mass of soot from
nostrils occurred on a regular basis. Residents also complained about drinking and domestic water
turning black. In specific instances, families and household members complained about windows,
bathtubs, bathroom, and kitchen sinks being completely covered with soot. Mopping of floors and
other household surfaces takes place at least three times a day. Residents compulsorily rewashed
and cleaned again, already washed and dried dishes before each use [
12
,
95
]. Those who depend on
rainwater, having no alternatives, use the soot-contaminated water. Having to face the effects not only
outside, but also inside their homes indicates the severity of the situation. Homes are no longer a place
of refuge, as soot find its way through unlocked doors and open windows. Deposits clog the protective
nets of such doors and windows [
93
]. Protesters used the opportunity to call on both the federal and
state governments to aim for a more permanent solution to the problem [
96
]. Although, reports suggest
that Abuloma, Iwofe, Rupokwu, Okrika, and Woji constitute the most impacted areas [
96
], affected
areas also include Rumuigbo, Eleme, and Oyibo Local Government Councils, as well as Ogoni [96].
4.2. Government Action
In February 2017, the Ministry of Environment declared the air pollution an “Emergency situation”.
This declaration was made “in an effort to immediately address the problem” [
97
]. In the same
month, the Governor Nyesom Wike-led administration set up a Task Force comprising of a three-man
committee, namely, Commissioners for Environment, Professor Roseline Konya; Special Duties,
Mr. Emeka Onowu; and, Information, Dr. Austin Tam-George. The principal duty of the committee
was to investigate the source of the pollution and find a resolution [
97
]. The government also advised
that residents should take such protective measures as “refrain from eating foods prepared outdoors,
including roasted plantain and suya; avoid drinking rain or exposed water; ensure all foods are
covered; keep doors and windows closed; ensure children are indoors and kept away from the floor;
and, adopt use of face masks. Asthma patients were advised to take extra care” [
96
,
97
]. Although some
residents expressed satisfaction in Rivers State government reaction to the problem, describing it
as “prompt, rising to the occasion and handling the problem headlong” [
94
,
98
]. Others claimed
government was slow in taking urgent necessary action [
12
,
14
,
99
]—it took the government more than
four months to respond to such an “environmental emergency” that put the lives of approximately
6 million citizens at risk [12,14,99].
4.3. Task Force Findings
According to reports, the Ministry of Environment results obtained from air samples collected
and analyzed in late December 2016 at various sites in the city, suggest an 11 times higher than WHO
specification for PM
2.5
. Collection of samples occurred between 12 a.m. and 6 a.m., implying that the
activities of the polluter(s) occurred at night. The minimum result obtained was 62
µ
g/m
3
[
96
,
100
].
According to the Commissioner of Environment, the report of analysis for samples obtained on

Environments 2018,5, 2 11 of 22
23 December, 2016, exceeded WHO specification for both PM
2.5
and PM
10
[
100
]. The Ministry of
Environment analyzed samples obtained at two different periods: 12 a.m. to 6 a.m. and 6 a.m. to
8 a.m., and from two locations in Port Harcourt, namely Abuloma Road and Peter Odili Road. For both
locations, they obtained 270
µ
g/m
3
for the 12 a.m. to 6 a.m. and for the 6 a.m. to 8 a.m. period,
125
µ
g/m
3
and 62
µ
g/m
3
for the two locations, respectively. This non-compliance suggest an 11-,
5- and 2.5- times higher values than the WHO standard for 24-hours mean PM
2.5
, respectively [
96
,
100
].
In an effort to address the situation, the special Task Force identified and shut down Chinese
Government Company (CGC), H&H Engineering Company, and AUC Asphalt Company. All three
located in Aluu community, were found to be discharging high volumes of emissions, therefore
contravening environmental regulations [
100
,
101
]. According to the Commissioner for Environment,
other suspected sources of the soot include activities of Illegal refineries, burning of tires, gas flaring,
liquefied natural gas (LNG) operations and processes, petro-chemical companies, and refineries [
100
].
4.4. Other Sources of Particle Polution
Some schools of thought suggest that there is an association between the emission of soot and
artisanal refining, as well as the burning of illegal refineries within the region [
96
,
99
,
100
]. Recent reports
indicate that the law enforcement agents have been seizing and burning illegal refineries. Furthermore,
equipment of operations and storage worth 3b naira from an accumulation of 40 illicit refineries
were destroyed in the “sanitizing mission”. According to reports, some residents considered the
action unethical, arguing that it amounts to a pollution equivalent of 10 to 20 incinerated tanker load
of crude [96,99].
4.5. Lessons from Nigeria’s 2014–2015 Ebola Virus Disease (EVD) Prevention
World leaders and experts, international organizations, professionals, and the academia
acknowledged Nigeria for preventing the spread of the EVD [
102
]. Various authors described the
2014–2015 EVD, declared as Public Health Emergency of International Concern (PHEIC), [
103
] an
outbreak with high pandemic potential of serious consequences. However, owing to the prompt
measures that the federal and state ministries of health embarked upon, EVD was significantly
controlled [
102
]. Lagos, Africa’s largest city, has a high population of 21 million [
104
], presents a fertile
ground for the spread of any epidemic such as EVD. That is, there was a high potential for transmission
given the dense population of Lagos, and being the nation’s business and travel center [102].
Research suggests that Nigeria’s success is attributable to the strategic action plan, rapid response
by the government to declare an emergency, easy communication flow, as well as inter-agency
collaboration [
102
,
105
]. The action plan that may serve as lesson learned for addressing the recent
Port-Harcourt air quality deterioration, both in the present and in the future, include, but not limited
to, strategic approach including immediate response, information dissemination; intergovernmental
partnership, and surveillance. Citizens engagement is also required.
5. The Role of Environmental Policy and Regulation
Nigeria’s environmental policy provides structural elements that encourage responsible
environmental behavior by individuals and industries. Formulation, enactment, implementation, and
enforcement of legislations that serve to offer environmental protection through effective action
towards environmental planning, as well as pollution prevention and control, help to achieve
environmental goals. Section 20 of the 1999 Constitution of the Federal Republic of Nigeria [
106
],
which makes provision for environmental preservation and upgrade, establishes the fundamental idea
of environmental policy in the country. Consequently, it is mandatory that the Nigerian State enforces
the protection of air, land, and water, as well as ecosystems, including forests and wildlife [
106
].
The Federal Environmental Protection Agency (FEPA), established by the FEPA Act in 1988, was
responsible for national environmental management and protection. However, in 1999, it was replaced,

Environments 2018,5, 2 12 of 22
and subsequently its functions taken over by the Federal Ministry of Environment (FME), the central
administrator and regulator of environmental laws in Nigeria [107].
5.1. Environmental Impact Assessment (EIA) Act 1992
EIA is a key legislation in Nigeria. It demands that prior to embarking on projects, private and
public organizations are obligated to carry out an EIA. This is to ascertain projects’ likely significant
impacts (positive or negative) and suggest potential mitigation measures where necessary. Section 13
of the EIA Act [
107
] highlights situations or projects requiring an EIA. While, Section 2(1) emphasizes
the requirement of an EIA for private and public projects having a potential of significantly affecting
the environment, Section 2(4) [
107
] demands that written application by project proponents to the
agency precedes project commencement. This suggests that the approval of such applications and
their EIAs must undergo review by the ministry [107,108].
5.2. National Environmental Standards and Regulation Enforcement Agency (NESREA) Act 2007
NESREA Act [
109
] replaced the FEPA Act and the FME administers it. Relevant provisions
of NESREA Act include section 7, [
109
] which issues authority for conformity with statutory
environmental regulations on sanitation, pollution prevention, and control, through monitory and
regulatory standards. Section 8(1) (K) [
109
] mandates the agency to create and revise air and water
quality legislations; limitations of effluents; and, control of various harmful substances [107,109].
Some Regulations under NESREA
Relevant NESREA regulations include the following:
National Effluent Limitation Regulations
Section 1(1) [
109
] mandates industrial facilities to make provisions for pollution abatement
equipment that ensures effluent treatment. Similarly, Section 3(2) [
109
] requires that they present a
report of their treated effluent composition to the agency [107,109].
National Environmental Protection (Pollution Abatement in Industries and Facilities producing Waste)
Regulations (1991)
In addition to the requirement of Section 1 [
109
], which proscribes hazardous substances discharge
into the air, land, or water of Nigeria, Sections 4 and 5 [
109
] stipulate that should any discharges occur,
the industries must inform the agency and submit a comprehensive list of chemicals that are used for
production [107,109].
Federal Solid and Hazardous Waste Management Regulations (1991)
Section 1 [
109
] of this regulation, makes compulsory the identification by industries, of dangerous
solid hazardous wastes that constitute a threat to public health and the environment. Industries are
also obligated to research the potential of recycling such wastes. Similar to Section 3(2) [
109
] of the
National Effluent Limitation Regulations requirement, Section 20 [
109
] of this regulation demands that
operators formally inform the agency of the occurrence of any discharge [107,109].
Harmful Wastes (Special Criminal Provisions) Act of 1988
This Act bans transporting, depositing, and discarding of harmful waste in air, land, or water,
void of preapproved legal authorization, within the Nigerian state [107,109].
5.3. Factories Act, CAP F1, LFN 2004
The Nigerian federal government in an attempt to foster worker health and safety established the
Factories Act. Section 13 [
108
] of the Act authorizes a regulator or inspector decide that emergency

Environments 2018,5, 2 13 of 22
measures be taken by qualified person in the event of pollution. Section 30 [
108
] of the Act recommends
precaution for factory operations involving emission of explosive or inflammable dust, gas, vapor, or
other substances. Specifically, Section 45 [
108
] prescribes adoption of all practicable action to enhance
worker protection from inhaling dust or fume or other impurity. It also recommends the prevention of
any buildup of such pollutants in the work area [108].
5.4. Infringements and Penalties
The foregoing regulations make provisions for sanctioning offending individuals or businesses
for contravening established legislations under the various Acts. For instance, Section 27 of the
NESREA Act [
109
] stipulates a prohibition on unauthorized disposal of hazardous substances into the
environment. Contravention of this regulation attracts a maximum fine of one million naira, including a
five-year prison term. Furthermore, an additional fifty thousand naira fine is accruable for each passing
day the infringement continues. Violation of any provisions of the EIA Act incurs acts punishable
by law (Section 60) [
109
]. Section 108 109] of the Federal Solid and Hazardous Waste Management
Regulations 1991 specifies disciplinary action against offenders for violating any regulations, including
the discharge of hazardous substances into the environment, and the failure to notify the agency of
such discharges. The Harmful Wastes (Special Criminal Provisions) Act explicitly makes a provision
for forfeiture of land or any equipment or other facility employed in perpetrating the infraction; as
well as life imprisonment. Commensurate penalties are enforceable on any negligent company staff
who plots, colludes, and assents to commit an offence. Additionally, persons afflicted either by way
of being injured or by way of becoming ill become a liability to the offending individual. These are
stipulations of Sections 6, 7, and 12, respectively [107–109].
6. Discussion
6.1. Implications for Public Health
Port Harcourt is observing a “double air pollution burden”—the unresolved prevailing
widespread air pollution and the “added” emergence of particle pollution [
20
,
37
]. Global research
highlights the significant public health threat posed by human exposure to air pollutants including
PM. A plethora of health conditions, including life-threatening morbidities, as well as mortalities,
implicates the different fractions of PM as direct causative agents [5,7,10,11,43,58–92].
Although epidemiological studies investigating PM exposures’ relationship with morbidities and
mortalities in Nigeria is limited, a significant amount of epidemiological and toxicological studies in
Asia, Europe, the United States (US), and elsewhere in the world establish a strong association between
PM exposure and various diseases and deaths [
58
–
92
]. Studies also provide evidence showing the
potential susceptibility of specific at-risk population namely children, and older adults [73–85].
In a study to assess the effects of industrial air pollutants on the respiratory health of children,
Nwokocha et al. [
110
], in their 18-month prospective study, provide a strong correlation between
exposures to four criteria air pollutants, namely CO, NO
2
, SO
2
, and PM, and the incidence of bronchitis,
cold, cough, phlegm and sinusitis. Children less than two years of age, living in the populated area,
were 3.5 times more susceptible to the pollutants than were those in the less polluted zone. Likewise,
Onwuchekwa et al. [
111
] in a geriatric admission survey discovered that chronic diseases accounted
for a larger percentage of morbidities and mortalities among patients 60 years and above.
Correspondingly, growing evidence suggests correlation of PM exposure among people of low
SES with various health conditions and mortality [
86
–
92
]. Port Harcourt is a city in the Niger Delta, a
region where 50% of the population are living on less than $1.25. Moreover, it performs lower than
other parts of the country in terms of SES indicators: ambient air quality, availability of safe drinking
water, food safety, chemical exposures, residential environments, educational attainment, availability
of educational services and healthcare facilities, and household income based on number of people
living below poverty level.

Environments 2018,5, 2 14 of 22
Underdevelopment further compounds this problem. These are critical public health issues—in
Nigeria, children aged
≤
14 years constitute the largest population group (42.79% of 186 million) as of
2016 [
112
]. Addressing these public health issues to protect for the most part, the at-risk population
is important. The double air pollution burden thus presents a health concern. It should serve as a
reminder and further call to action to address not only the recent situation, but also the prevailing
pollution problem in Port Harcourt, and indeed, the entire Niger Delta.
Some of the health effects of the poor air quality occasioned by the emissions that lasted for months
may not be immediate, however, given the duration and the “above limits” concentrations recorded
by the Ministry of Environment, a rise in the prevalence of airborne-related diseases in the affected
areas is probable. It is noteworthy that research suggests that short-term (hours to days) exposure to
PM
2.5
is correlated with an increased risk of hospital admissions for aggravated acute IHD [
63
], and
aggravated asthma in children [
69
]. Low SES, particularly living below poverty level, is associated with
increased risk of mortality among population exposed to short-term PM
2.5
exposure [
83
]. In a similar
manner, residential environment significantly correlates with higher mortality risks for short-term
PM2.5 exposures [92].
Evidence of preexisting health problems from research study by Weli et al. [
113
] provides support
to the probable near future morbidities and perhaps, mortality rise. The researchers evaluated
the relationship of spatial incidence of CVDs with the air quality of four selected abattoirs in Port
Harcourt. They limited their investigations to the roasting section, which generated large quantities
of smoke. The pollutants sampled and analyzed comprised CH
4
, CO, H
2
S, NO
2
, SO
2
, PM
2.5
, and
PM10. Findings indicate that pollutant concentration, age, job duration, as well as exposure duration,
correlated with the incidence of CVDs amongst workers. This may imply that such PM-related disease
as CVDs, CADs, CHF, and respiratory diseases, such as COPDs and asthma, may further rise above
currently reported rates due to the soot pollution.
6.2. Violations of Environmental Regulations
The root cause of companies emitting pollutants above stipulated standards is fundamentally
inadequate enforcement of existing environmental regulations and/or faulty/unedited environmental
policy framework. The current soot pollution adds to the existing violation of environmental policy
by the oil and gas industry that has for decades left the Niger Delta in widespread pollution [
20
].
However, the current particle pollution event comes as “unexpected”, because the three Ministry of
Environment-sealed factories do not fall under the “more difficult to regulate” oil and gas sector.
Considering the relevant environmental legislations highlighted in Section 5, it is obvious that
violations of national environmental regulations occurred—not so much so that polluting companies
failed to implement rudimentary environmental legislations, but that there was probable negligence
on the part of the regulating agencies to either enforce them or ensure adequate monitoring of
implementation by businesses. The EIA Act (Decree No. 86 of 1992) [
107
] makes provisions for
all of the categories of industry to implement fundamental environmental laws. These provisions
emphasize environmental management (EM) as their target. Included within the scope of EM is the
environmental management system (EMS). Both of these concepts are “products” of EIA and assure
that the overall goal (EM and its goals) of EIA is achieved not only prior project commissioning, but
also post-commissioning. It also assures that attaining the ultimate goal of pollution prevention is
continuous, and is sufficiently maintained throughout the life of the project. The overarching goal of
EM is environmental public health safety [41].
The fact that Nigeria has a plethora of unimplemented environmental laws and a growing
occurrence of industry infractions of environmental legislations cannot be overemphasized [
114
].
One major issue that arose in the event of the soot pollution episode is the fact that responsible
regulating agencies should have prevented the event from occurring in the first place [
14
]. Some school
of thought expressed their concern and raised such pertinent questions as: “Who cleared the Chinese
company to start operations? Who is the Environmental Health Officer at the local government where it

Environments 2018,5, 2 15 of 22
operates?” They further expressed concern about how the responsible agencies were uncertain what to
do at the onset of the pollution, describing setting up of the special Task Force as “inessential” because
even a “blind man could perceive the very palpable pollution” [
14
]. Additionally, they considered it
“inexcusable” that the Ministry of Environment would allow such big companies discharge high levels
of factory emissions into the environment without executing urgent necessary action. They emphasized
the indispensability of the Environmental Impact Assessment (EIA) requirement, asserting that
enforcement at all levels of business operations is mandatory [14].
Indeed, an EIA would have determined the kind, and possibly, quantities of effluents of the
Asphalt and other polluting companies would be discharging prior project commissioning. It also
would have proffered mitigative solutions; otherwise, project approval should not have occurred
in the first place. Aside from the issue of EIA, another very vital question that requires attention
is “what about routine (monthly or quarterly) inspections by the regulating agencies, such as the
Ministry of Environment and Environmental Protection Agency (EPA)?” Under normal circumstances,
execution of appropriate environmental laws detects such nonconformities and prevents escalation of
the problem.
In expressing his concerns about the environmental health problems in Ogoniland, Yakubu [
41
]
recommended an environmental management/environmental management system (EM/EMS) model.
This encompasses all the necessary tools, procedures, and processes required for pollution prevention
for businesses. The model makes room for an independent environmental consultant accredited by
the responsible environmental agencies to provide professional services to businesses and serve as a
liaison between companies and the agencies. This adds to the strategies of pollution prevention.
Environmental consultants facilitate compliance with statutory environmental legislations and
help businesses realize their environmental goals. Among other things, the EM/EMS model
underscores the vital role company environmental policy plays in achieving environmental goals,
including pollution prevention. The extent of EMS adoption determines what the outcome for pollution
prevention is [
41
]. Nevertheless, a major requirement for achieving company environmental goals
through the implementation of EM/EMS is in conformance with environmental regulations. This is
where environmental monitoring and/or periodic environmental inspection by state or federal agencies
plays a significant role.
Regarding the seizure and destruction of equipment, properties, and oil products from artisanal
refineries by the Military, a more responsible approach is required. Statutory environmental legislations
require that it is incumbent upon the federal and state Ministries of Environment or the designated
regulating agency to take charge of the disposal of confiscated materials [107].
6.3. Current Situation
The website of the Ministry of Environment does not provide any current information about the
situation, so the public lacks access to up-to-date information for them to make informed decisions
if and where necessary. There is inadequate information as to if investigations are still ongoing as
declared by the ministry.
7. Conclusions
Governmental rapid response to the 2014–2015 EVD in Nigeria provides a good template for
addressing environmental health emergencies. It is commendable that the government declared
an Emergency Situation in February 2017, and requested that residents take protective measures to
enhance health and safety. However, residents may have appreciated immediate action more, and
considered it timelier, particularly at the onset of the event. Immediate response may have prevented
public protest. Although EVD is a very serious disease and action taken by the government to prevent
its spread was commensurate to its virulence and pathogenicity, nevertheless, to a certain extent, the
application of some of the strategies to the soot pollution may have reduced its impacts. Some opinions
may suggest that there is no basis for comparing the EVD outbreak with soot pollution in terms of

Environments 2018,5, 2 16 of 22
severity, it is, however, important to mention that epidemiologic evidence suggests that short-term
exposures (i.e., hours to days) to PM
2.5
fraction correlates positively with mortality among exposed
humans. Therefore, particle pollution is also a serious environmental health issue.
Immediate response to the PM emission implies prompt environmental investigations (finding out
the source of the pollution and conducting environmental audit); environmental risk communication
using the electronic and social media, to keep the public informed; surveillance in terms of
environmental monitoring (sampling and analyzing air samples and generating scientific quantitative
data), and information dissemination (communicating up-to-date results to the public). Another step
that was taken by the Nigerian government in its successful prevention of the spread of EVD was
the cooperation among stakeholders in form of multiagency concerted intervention. Addressing the
current environmental health emergency would benefit from a pool of resources by the River State
Ministry of Environment Port Harcourt, River State Environmental Sanitation Authority Port Harcourt,
and River State Environmental Protection Agency. Efforts from academia and non-profit organizations
will also benefit intervention efforts. Additionally, population health risk has probably increased
by way of exposure to particle pollution. An epidemiologic evaluation of this risk and its overall
health effect on the exposed population in terms of morbidity and mortality is necessary to enable
the government make informed decisions and to take further action. Academia and the Rivers State
Ministry of Health have significant roles to play in terms of conducting intensive research including
prospective and retrospective epidemiological studies.
Following EIA, routine environmental inspection and monitoring by regulatory agencies is
required to forestall future reoccurrences. The various environmental laws require implementation.
Disposal of seized materials from artisanal refineries require more environmental responsible approach
to assure environmentally friendly measures that prevent pollution. Responsible environmental
agencies should be involved. Citizens involvement in terms of possession of affordable and portable
air monitoring devices to record and report above limits ambient criteria air pollutants would be
beneficial. However, education of the public, as well as easy access to the ministry, is required for such
efforts to be successful.
Additionally, it is important that the Ministry provide answers to such questions: what is the recent
concentration of ambient PM? What ongoing efforts are in place to put an end to reoccurrence, including
action taken against the offenders, and what probable proportion of the pollution is attributable to the
indicted sources?
Acknowledgments:
I will like to thank Michaela Buenemann, Department of Geography, New Mexico State
University, for kindly creating the map. I also thank Joseph Gladstone, Public Health Sciences Department,
New Mexico State University for reviewing my draft manuscript.
Conflicts of Interest: The author declares no conflict of interest.
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