1. science
2. ecology
3. pollution

African Journal of Physics Vol.3, 2010.
AIR POLLUTION AND ITS POSSIBLE HEALTH EFFECTS ON
RURAL DWELLERS IN RIVERS STATE, NIGERIA†
.
1
Nwachukwu, A.N. and 2Ugwuanyi, J.U.
1
Dept. of Physics, University of Port Harcourt, Port Harcourt, Rivers, Nigeria.
2
Dept. of Physics, University of Agriculture, Makurdi, Benue, Nigeria
2
E-mail: [email protected]
Abstract
This research work examines the health effect due to air pollution on rural
dwellers in Rivers State. Epidemiological data of ten(10) selected Local
Government Areas in the state for 1985 , 2003, 2004, 2005, 2006 and 2007 were
collected from the state Ministry of Health. The 1985 data was used as a control
to the experiment. The most recent Ambient Air Quality (AAQ) data of the state,
the National Ambient Air Quality Standard (NAAQS) data and the summary of
the Updated World Health Organization Air Quality Guideline (WHOAQG) data
were equally collected for the purpose of comparison. The data collected were
used for formulating and testing air pollution models. The result shows that a total
number of 13,243 cases were reported, out of which 29 patients died within the
period of review. The diseases found to be prevalent in the study area as a result
of air pollution include pertusis, pulmonary tuberculosis, CSM, pneumonia,
measles, chronic bronchitis, and upper respiratory tract infection (URTI). The
ambient air quality in the state is far worse than the World Health Organization
Air Quality Standard. This points to their unsafe levels and concomitant health
risks. The environmental impact matrix of the patients versus the diseases is a
revelation that pollution is already affecting the quality of life and productivity of
the people. It is against this background that a case is made for the intensification
of environmental education, especially among rural dwellers in the state.
† African Journal of Physics Vol.3, pp. 217-240, (2010)
ISSN: PRINT: 1948-0229 CD ROM:1948-0245 ONLINE: 1948-0237
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African Journal of Physics Vol.3, 2010.
Keywords: Air pollution; Health effects; Rural dwellers; Environmental
education.
1. INTRODUCTION
The human environment is the basis for any economic, social and cultural
development (Iyoha, 2000). It is therefore pertinent that its quality be maintained
in a good state to ensure a high level of social performance, which can be
achieved through closer monitoring of the pollutants and their effects. This is
because, the issue of environmental degradation in the twenty-first century is of
global concern relative to its resultant health implications (Avwiri and Ebeniro,
1998).
The clamour for harnessing the natural resources for technological
development has led to the degradation of the natural environment (Avwiri and
Ebeniro, 1998). Industrialization, though an important component of development
has had a large share in the release of high amounts of pollutants into the
atmosphere (Osuji and Avwiri, 2005).
Today, there is undoubtedly a high rate of atmospheric pollution in Nigeria
especially in the industrial areas of the nation. For example, the air over Lagos,
where about 38% of the manufacturing industries in the country are located, has
since 1983 been credited with characteristic unpleasant odour. The Niger-Delta
region of Nigeria where oil and gas are produced is indeed, another obvious
example (Avwiri and Ebeniro, 1998). These pollutants are emitted in the form of
gas, and particulate matter (Rao and Rao, 2001).
The natural gas regularly burnt and released into the atmosphere during the
production of oil and gas amounts to a double whammy against the environment,
wasted resources and additional green house gas emission (PTDF, 2004). To
combat this the world Bank Launched a Voluntary Global Standards earlier this
year to provide more incentives for getting this gas to market, particularly in
Africa and in the Middle East, where most flaring and venting occur. As of this
fall, countries accounting for more than 70% of flaring and venting globally had
signed on to the partnership (PTDF, 2004; World Bank, 2005).
The gas released when crude oil is brought to the surface is known as
associated gas (AG) (PTDF, 2004). Drilling companies routinely flare or vent this
material for safety reasons or where there are no infrastructures to bring it to
market. This practices had been dramatically curbed in developed countries, but
the World Bank estimates show that more than 100 billion cubic meters of gas is
still flared or vented worldwide annually (World Bank, 2005).
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African Journal of Physics Vol.3, 2010.
In spite of efforts by countries and companies to capture more of this gas
for energy, global flaring and venting levels remained fairly constant over the past
20 years. In Nigeria, this was accompanied by the 1973 – 1980 oil boom (Osuji
and Avwiri, 2005; Ugwuanyi and Obi, 2002) especially in the South-South geopolitical enclave of the country popularly called the Niger-Delta where Rivers
State is located. The flaring of associated gas (AG) in the Niger-Delta is a human
right, environmental and economic monstrosity (ESMAP, 2004; ERA, 2000).
Nowhere else in the world have communities been subjected to it on such a scale.
It is estimated to cost Nigeria US$2.5 billion annually, whilst the roaring toxic
flares affect the health and livelihood of Delta inhabitants; especially the rural
dwellers (ESMAP, 2004). It is estimated that over 66% of Nigerians live below
the poverty line (ESMAP, 2004). Gas flaring contributes significantly to climate
change, thus effecting communities all over the world (WATCHTOWER, 2008).
Oil production levels determines the amount of AG production, the more
the production of oil, the more also would be the amount of AG produced. While
AG flaring has been increasingly frowned at in most part of the world, in Nigeria,
it has flourished. The rate and level of connection was summarized in a June 2001
speech by SPDC’S current Chief Executive Mr. Basil Omiyi.
”On the average, about 1000 standard cubic feet (scf) of gas is produced in
Nigeria with every barrel of oil. Therefore, with oil production some 2.2million
barrels per day, about 2.2 billion scf of associated gas is produced everyday”
(ESMAP, 2004).
Table 14.0 explains more, as it elucidates associated gas production by
company, 2000 -2002 MCFD according to UNDP/world Bank. Table 15.0
according to World Bank for year 2000 also shows Nigeria as flaring most gas,
both absolutely and proportionately, about 46% of Africa’s total, and as flaring
the most gas per ton of oil produced, albeit at a less bad ratio than in 1990; thus
placing Nigeria as the world biggest flarer.
On the basis of the OPEC figures for the year 2000, Nigeria flares about
16.8 bcm/y of gas, Nigeria again comes out as the world’s number one flarer and
venter on both absolute and proportionate basis. The Nigeria amount is higher
than the nearest African country, Algeria, which is recorded as having flared and
vented 4bcm.
Apart from gas flaring, particulate matter could be considered as nongaseous concentration in the atmosphere and represent an index of divers classes
of substances often referred to as aerosols (Ross, 1972; Warner, 1976; Sell, 1981).
These materials which are both solids and liquids, are suspended particles and
could be air-borne for long periods of time (Giddings, 1972; Sell, 1981). They are
often classified by their sizes, which are invariably responsible for the kind of
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effects they create in the environment. Particulate matters are chemically diverse
and could contain variety of trace metals among others, that are responsible for
their toxicity to the ecosystem (Jaffer, 1967; Lynn, 1976).
Dust particulates are very prevalent in urban atmospheric environment due
to the large scale variety of anthropogenic activities that release huge amounts of
terrestrial materials and their primary and secondary products into air (Ugwuanyi,
1997; Ogri, Obi-Abang and Uyana 1999). Particulate air pollutants are a major
problem in developing countries due to excessive use of fossil fuels, especially
petroleum and coal with wood (Khan and Khan, 1996). In Nigeria, there is high
proliferation of power generation plants due to the unreliable power source, and
the use of fossil fuels that generate quantities of particulate matters (Giddings,
1973).
The main sources include industrial, construction and auto mobile
transportation (UNEP,1996; Sell, 1981; Young, 1974). Specific sources could
include smoke stacks from industries, bush burning, exhaust emission, power
generating plant that use fossil fuels etc. construction work involving large scale
earth moving equipment could cause dust particulate cover in an aerial scale
(UNEP, 1996), but massive air borne plumes of the desert dust particles is said to
be responsible for dust particulate cover in continental and intercontinental scale
(Moulin et al,1997).
In Urban environment, dust particulate cover has been widely known to
reduce visibility and disrupting traffic including air travels in extreme cases
(Giddings,1973; Dorman, 1974; Berry and Horton, 1974; Young and Bibbero,
1974; Frank and Frank, 1975).
In many urban areas dust particulate matter in a large scale is associated
with dust haze that greatly disrupt air travels during the hamattan weather and
other climatic effects (Utah, 2007). For example, particulate matters tend to form
blankets that shield the land from the warming sunlight when excess UV radiation
from the sun is screened from the earth surface (a kind of greenhouse effect),
(Giddings, 1973). They also form condensation nuclei for rapid cloud formation
and rainfall (Gray, 1978; Sell, 1981), thus affecting local climate. In public health
they have been associated with heart and lung diseases, with cancer of the lungs
(Gray, 1978; Sell,1981). Other effects of atmospheric particulate cover vary from
damage to vegetation to even nuisance (Sell, 1981).
In the face of this dangerous development, the people of Rives State, who
are predominantly rural dwellers and located in the South –South part of Nigeria,
with almost the highest number of oil companies (such as SPDC, Exon Mobil,
Chevron Texaco, Agip, etc) in Africa, and numerous cement companies, surely is
the worst hit. The problems due to air pollution in recent years in the state must
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have been seriously aggravated because of the presence of these contributors.
Below are listed air pollutants and the associated diseases.
i)
Respiratory – irritation, decreased pulmonary function.
ii).
Particulate matter –Stress on the heart, bronchial constriction, impairment
of lung elasticity and gaseous exchange
efficiency, silicosis (a form
of pneumoconiosis caused by inhalation of dust particles), respiratory tract
disease systematic
toxicity, altered immune defense.
iii).
Cement dust – Pulmonary tuberculosis, allergic asthma, pneumonia, heaty
diseases, bronchitis, influenza, emphysema, and
mycosis.
iv).
Carbondioxide – Reduces the quantity of O2 transported to tissues, hence
can impress extra on those suffering from anemia,
chronic
lung
conditions heart and blood vessel diseases, brain damage, impaired
perception, eye and nasal
irritation, lung damage respiration tract
disease.
v)
Lead/asbestos – Causes asbestosis (chronic lung cancer), and
mesothelelionia (a rare form of cancer), kidney disease and neurological
impairment, primarily affects children.
vi).
Photochemical oxidants (e.g ozone) – Long exposure to it can cause
reduced eye-sight, fatigue, pneumonia, pulmonary headache, breathing
difficulties, chest pain, burning sensation to throat and eye, respiratory
disease, aging of lung and respiratory tissue.
vii).
Sulfur dioxide – respiratory irritation, shortness of breath, impaired
pulmonary function, increased susceptibility to infection, illnesses to
lower respiratory tracts (particularly in children), chronic lung diseases,
pulmonary fibrosis, increase toxicity in combination with other
pollutants.
viii).
Carbon monoxide – Interferes with oxygen uptake into the blood (chronic
anoxia), heart and brain damage, impaired perception,
asphyxiation,
weakness, headache and nausea.
In the continuing search for lasting solutions to problems caused by air pollution,
one approach, we believe, is to obtain information on the health effects of
environmental pollution on rural dwellers who, indeed, are worst hit, as they have
little or no knowledge about the hazardous nature of these pollutants. It is against
this background that we present our findings in this regards sequel to a study
conducted in Rivers State, Nigeria.
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2. MATERIAL AND METHODS
Study Design
This research study covers five years (2003 -2007) in Rivers State, Nigeria.
Epidemiological data of all the people from ten(10) selected Local Government
Areas (as indicated in routine monthly notification form supplied by World health
Organisation (WHO)) treated for air-borne related diseases in 1985, 2003, 2004,
2005, 2006 and 2007 in the state were collected from the state ministry of Health.
The 1985 data were used to control the experiment. The Local Governments are:
Eleme, Ikwerre, Degema, Bonny, Okirika, Ahoada East, Ahoada West,
Obio/Akpor, Oyigbo, and Emuoha. It is important to note that the 2003-2007 data
collected from the state ministry of health covering the ten selected Local
Government Areas represent the sum of the incidences from all the hospitals
within these study areas.
The most recent Ambient Air Quality (AAQ) data of the State, the National
Ambient Air Quality Standard (NAAQS) data and the summary of the Updated
World Health Organization Air Quality Guideline (WHOAQG) data were equally
collected for the purpose of comparison..
Disease Terms Used in the Study
Pneumonia (pneumoconiosis) --- This is a fibrous indurations of the lungs due to
irritation caused by the inhalation of dust, especially in certain occupations, as a
coal mining, stone cutting, or the like. It includes hypertensitive pneumonitis due
to inhaled organic dust and particles of fungal (Ugwuanyi and Obi, 2002).
Pulmonary tuberculosis---tuberculosis of the lungs, bacterially and historically
negative (Ugwuanyi and Obi, 2002). Both the respiratory and the gastrointestinal
tracts have been proposed as entry portals for its pathogen. However, person to
person transmission is not very efficient (Willy, Sherwood, and Wooverton,
2008).
Measles--- The virus enters through respiratory tract or conjunctiva of the eyes.
The incubation period is usually 10-20 days and the first symptoms begin with
a nasal discharge, cough, fever, conjuvtivitis, headache etc. Within 3-5 days, skin
eruption occurs (Willy, Sherwood, and Wooverton, 2008).
Meningitis--- Cerebrospinal meningitis. This an inflammation of the brain or
spinal cord meninges (membrane) (Willy, Sherwood, and Wooverton, 2008).
Pertussis--- This is caused by gram negative bacterium (Bordetella Pertussis).
They colonize the respiratory epithelium to produce a disease (Whooping
Cough). It is characterized by fever, malaise, cough. Transmissionoccur by the
inhalation of the bacterium in droplets released from an infectious person
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(Brooks, Carrol, Butel, and Morse, 2007).
3. RESULTS AND DISCUSSION
The air-borne diseases found to be common in the study area are measles,
pulmonary tuberculosis, cerebrospinal meningitis, pertusis (whooping cough) and
pneumonia, while chronic bronchitis and upper respiratory track infection (URTI)
are relatively low.
In 2003, a total no. of 2242 incidences were recorded, 340 for measles, 282 for
pulmonary tuberculosis, 65 for cerebrospinal meningitis (CSM), 82 for whooping
cough (pertusis) and 1473 for pneumonia which has the highest frequency for the
year, with LG9 (Bonny) recording the highest number (171) of incidence of
Pneumonia for the year. A total number of 1 patient died (Tabs. 1, 6 - 13.) (Figs. 3
– 9)
In 2004, a total number of 3430 incidences were recorded, 635 for measles, 406
for pulmonary tuberculosis, 72 for CSM, 73 for pertusis and a total of 2244 for
pneumonia which equally emerged as the highest in occurrence for the year. LG7
(Eleme) recorded the highest number (250) of incidence of Pneumonia for the
year. A total of 10 deaths were recorded, 3 for measles, 4 for pulmonary
tuberculosis, 1 for CSM and 2 for pneumonia. Here, pulmonary tuberculosis
recorded the highest number of deaths for the year. (Tabs. 2, 6 - 13.) (Figs. 3 – 9)
In 2005, a total of 2751 incidences were recorded, 287 for measles, 366 for
pulmonary, 68 for CSM, 62 for pertusis and 1968 for pneumonia. Pneumonia
again emerged highest.. LG7 (Eleme) recorded the highest number (223) of
incidence of Pneumonia for the year. A total of 16 deaths were recorded for the
year, 3 for measles, 6 for pulmonary tuberculosis and 7 for pneumonia. (Tabs. 3, 6
- 13.) (Figs. 3 – 9)
In 2006, a sum of 2479 incidences were recorded, 228 for measles, 255 for
pulmonary tuberculosis, 75 for CSM, 62 for pertusis and a whooping total of 1859
for pneumonia and again with the highest frequency LG9 (Bonny) recording the
highest number (220) of incidence of Pneumonia for the year. A total number of
1 death was recorded and it came from pneumonia. (Tabs. 4, 6 - 13.) (Figs. 3 – 9)
Similarly, in 2007, a total of 2762 incidences occurred; 78 for measles, 300 for
pulmonary tuberculosis, 60 for CSM, 51 for pertusis and 2273 for pneumonia.
Pneumonia equally has the highest frequency on annual basis for individual
diseases. LG3 (Degema) recorded the highest number(267) of incidence of
Pneumonia for the year. A total number of 1 death occurred, and this time from
pulmonary tuberculosis. (Tabs. 5, 6 - 13.) (Figs. 3 – 9)
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TABLE 16 : NATIONAL AMBIENT AIR QUALITY STANDARDS
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Table 17: SUMMARY OF THE UPDATED AQG LEVELS (1975)
They are recommended to be achieved everywhere in order to
significantly reduce the adverse health effects of pollution
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It is worthy of note that a total number of 13,243 incidences were recorded within
the period of review (i.e 2003 – 2007), with an annual average of 1,324
incidences and total number of 29 deaths corresponding to an annual average of
approximately 3 deaths. Pneumonia equally emerged with the highest number of
incidences both on annual basis. It equally has the highest incidences within the
period of review (i.e 2003 -2007).Bonny Local Govt. Area recorded the highest
occurrence of Pneumonia(i.e 1196) followed by Eleme Local Govt. Area with a
total number of 1080 cases. This is due to the existence of one of the nation’s
largest sea ports in Bonny where emissions from industrial activities and
automobiles take place, and a refinery in Eleme where gas flaring is the order of
the day.
Table12 shows the annual recorded of death incidences for each of the
diseases and their total. For example, in 2003, a total number of 1 death incidence
occurred, 10 in 2004, 16 in 2005, 1 in 2006 and 1 in 2007. Measles has a total of
7, 13 from pulmonary tuberculosis, 1 from CSM, none from pertusis, and 9 from
pneumonia, bringing it to a total of 29 death incidences within the period of
review (2003 – 2007).
A comparison of Tables (1 to 5) and 6 shows that the studied air-borne
diseases were relatively low during which only few industries were established.
In 1985, only 69 patients were recorded with these diseases per annum (Tab.6),
about 20 years later after which the state had attained peak in industrialization, an
average of 1,324 patients contracted the diseases in a year. Similarly, in 1985, 14
deaths were recorded, out of 69 incidences (i.e 20.3% of the patients treated died.
In 2003, 1 patient died out of 2223 (ie 0.045%), in 2004, 10 deaths occurred out
of 3364 incidences (i.e 0.3%), in 2005, 16 deaths were recorded out of 2651 (i.e
0.6%). In 2006, 1 death incidence was recorded out of a total of 2345 incidences
(i.e 0.043%), in 2007 1 patient died out of 2660 (0.04%) patients who received
treatment. Over 74% of all the patients, suffered from pneumonia attacks (Tabs. 1
– 5). Upper respiratory tract infection (URTI), chronic bronchitis, and
cerebrospinal meningitis (CSM) are relatively low in the state. These findings
suggest strongly that air pollution is one of the major causes of health impairment
in the state.
CONCLUSIONS
The results of this research work suggest that the lower atmosphere of
Rivers State is polluted by gases and particulates, and that this is already affecting
the quality of life and productivity of the people. A total number of 13,664 cases
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were reported, out of which 29 patients died with pneumonia having the highest
frequency within the period of review. The diseases found to be prevalent in the
study area include pertusis, pulmonary tuberculosis, CSM, pneumonia, measles,
chronic bronchitis, and upper respiratory tract infection (URTI).
Given the fact that greater percentage of the land mass is covered by water
that by land, the population densities of Rivers State (181persons/km2) the
settlement characteristics of the people (compact traditionally mud houses with
little or no ventilation, and the overall poverty level in the country, the number of
rural dwellers who have suffered and died due to these diseases is likely to be
more than officially reported and recorded. There was no record about the
people’s smoking habit. The AAQ (Tabs.14-15) in the state exceeds both the
national and international standards (Tabs. 16-17); and the incidences of the
disease during the advent of industrialization was low relative to the
contemporary cases (Tabs.1-5 and 13). We therefore conclude that the diseases
are likely to be due to air pollutants.
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