Fisheries in Ghana and the state of pollution of water bodies and their effect on the living organisms in the estuary.

1. KWAME NKRUMAH UNIVERSITY OF SCIENCE AND
TECHNOLOGY
COLLEGE OF AGRICULTURE AND NATURAL RESOURCES
DEPARTMENT OF FISHERIES AND WATERSHED
MANAGEMENT
HEAVY METAL CONCENTRATION IN THE SEDIMENTS AND
FLESH OF BOE DRUM (Pteroscion peli) AND GREATER
AMBERJACK (Seriola dumerili) FROM THE KORLE LAGOON
ESTUARY, ACCRA, GHANA.
A THESIS SUBMITTED TO THE FACULTY OF RENEWABLE
NATURAL RESOURCES IN PARTIAL FULFILMENT OF THE
REQUIRMENTS FOR THE AWARD OF BACHELOR OF SCIENCE
DEGREE IN NATURAL RESOURCE MANAGEMENT
ABOAGYE HACKMAN RICHARD
MAY 2012
i

2. ABSTRACT
The Korle Lagoon in Accra, Ghana, has become one of the most polluted water bodies on
earth. Different aquatic organisms often respond to external contamination in different
ways, where the quantity and form of the element in water, sediment, or food will
determine the degree of accumulation. The concentration of copper (Cu), Lead (Pb), Zinc
(Zn), and Cadmium (Cd) in the flesh of Pteroscion peli and Seriola dumerili were
assessed from October 2011 to January 2012. Eight fishes were sampled for each fish
species. Sediments were taken from three different sites on a monthly basis at the estuary
of the Korle lagoon. Samples collected were digested with a di-acid of the ratio 9; 4 of
nitric acid and perchloric acid respectively. Heavy metal was determined using the
Atomic Adsorption Spectrophometer (AAS). Heavy metal concentrations in sediment
were below the National Oceanic and Atmospheric Administration (NOAA) Sediment
Quality Guideline for Estuaries over the period and ranked in the order: Pb> Zn> Cu>
Cd. The result of this research showed that heavy metals were continuously deposited and
removed from sediments into the water column of the Korle lagoon estuary. Also the
study indicated that the levels of metal in the flesh of Seriola dumerili and Pteroscion
peli were low for, copper and zinc but higher for Lead and Cadmium as compared to the
World Health Organization Standard (2005). Heavy metal concentrations in the flesh of
S. Dumerili and P. peli in relation to size revealed that both sizes accumulated higher lead
and cadmium concentrations and lower Zinc and Copper concentration. The present study
showed that consumption of fish from the Korle Lagoon estuary should be prohibited and
should be discouraged because of the high levels of Pb and Cd in the flesh of Seriola
dumerili and Pteroscion peli in both small and large sizes.
ii

3. ACKNOWLEDGMENT
I thank the most high God for the strength and calm through the perplexing times during my
study.
I wish to express my deepest appreciation to my supervisor, Dr Nelson W Agbo, for his
invaluable comments and excellent supervision. I must also thank him for the cordial relations
showed towards me, which was very helpful and very much cherished.
My thanks also goes to Mr Kwasi Adu Obirikorang for being my second supervisor, assisting me
on field, laboratory and in putting this together.
I wish to thank Mr Napoleon Jackson and Mr Douglas for their assistance in the laboratory. I
thank my mum, Miss Monica Hackman so much for her inspiration, motivation and financial
assistance in putting this thesis together. My thanks also go to the entire membership of Christ
Apostolic Church, Odorkor Official Town Assembly for their prayers into this dissertation.
My sincere thanks also go to the following persons Mary Abena Yamoah, Enoch Adjei Mensah
and Solomon Antwi for their diverse assistance in the preparation of this dissertation.
My special thanks go to Mr. Daniel, Maame Awotwe, Sister Violet and all fishers of the Korle
Lagoon Estuary.
iii

4. TABLE OF CONTENT
CONTENT PAGE
ABSTRACT.............................................................................................................................ii
ACKNOWLEDGEMENT.....................................................................................................iii
TABLE OF CONTENT…………………………………………………………………………………….iv
LIST OF TABLES.................................................................................................................vii
LIST OF PLATES................................................................................................................viii
LIST OF FIGURES................................................................................................................ix
1.0. INTRODUCTION.....................................................................................................1
1.1. Justification....................................................................................................................2
1.2. OBJECTIVES....................................................................................................................4
2.0. LITERATURE REVIEW..............................................................................................6
2.1. Global Water Pollution...................................................................................................6
2.1.1. Environmental Aquatic Pollution...............................................................................................8
2.2. Heavy Metals.................................................................................................................9
2.2.1. Source of Heavy Metals...........................................................................................................10
2.2.2. Sediments and Heavy Metals in Estuaries...............................................................................11
2.3. Some Common Heavy Metals.......................................................................................12
2.3.1. Copper......................................................................................................................................12
2.3.2. Lead..........................................................................................................................................13
2.3.3. Zinc...........................................................................................................................................15
2.3.4. Cadmium .................................................................................................................................16
2.4. Bio-Importance of Heavy Metals to Humans................................................................17
2.4.1. Effect of bioaccumulation on humans.....................................................................................18
2.5. Lagoon Pollution in Ghana............................................................................................20
2.6. State of the Korle lagoon..............................................................................................21
2.6.1. Heavy metal sources to the lagoon.........................................................................................22
2.6.2. Effect of Korle lagoon pollution...............................................................................................23
2.6.3. Activities at the estuary...........................................................................................................23
2.7. Fish Species..................................................................................................................24
2.7.1. Seriola spp................................................................................................................................25
2.7.2. Pteroscion peli.........................................................................................................................26
3.0. METHODOLOGY...................................................................................................27
iv

5. 3.1. Description of the study area ......................................................................................27
3.2. Sample collection.........................................................................................................28
3.3. Heavy Metal Analysis ..................................................................................................31
3.3.1. Sample Digestion.....................................................................................................................32
3.3.2. Sediment digestion..................................................................................................................33
3.3.3. Determination of heavy metal concentration.........................................................................34
3.3.4. Measurement of Physicochemical Water Parameters............................................................35
4.0. RESULTS...............................................................................................................36
4.1. Heavy metal concentrations in Sediment Samples.......................................................36
4.2. Heavy metal concentrations in Pteroscion peli.............................................................37
4.3. Heavy metal concentration in Seriola dumerili.............................................................38
4.4. Heavy metals in the flesh of P. peli and the S. dumerili in relation to sizes...................40
4.4.1. Pteroscion peli ........................................................................................................................40
4.4.2. Seriola dumerili........................................................................................................................41
4.5. Physicochemical Parameters of the Korle lagoon ........................................................43
5.0. DISCUSSION.........................................................................................................44
5.1. Heavy Metal Concentration in Sediments.....................................................................44
5.2. Heavy Metal effect in fish species................................................................................46
5.3. Variation in Metal Concentrations in Relation to Body Size..........................................47
6.0. CONCLUSIONS.....................................................................................................48
6.1. RECOMMENDATIONS...................................................................................................48
REFERENCES..............................................................................................................50
v

6. LIST OF TABLES
TABLE PAGE
Table 4.1 Heavy metal concentration (μg/g ww) concentration in the sediment
from the Korle lagoon estuary.............................................................. 37
Table 4.2 Heavy metal concentration (μg/g ww) in the flesh of Pteroscion peli
from the Korle lagoon estuary............................................................... 38
Table 4.3 Heavy metal concentration (μg/g ww) in the flesh of Seriola dumerili
from the Korle lagoon estuary....... ...................................................... 40
Table 4.4 Physiochemical parameters ......................................................................43
vi

7. LISTS OF PLATES
PLATES PAGE
Plate 1 Pteroscion peli ……………………………………………………………..
29
Plate 2 Seriola dumerili ………………………………………………………….... 29
Plate 3 Beach seining at the Korle lagoon estuary ……………………………..... 30
Plate 4 Obtaining samples from fishers ………………………………………….. 30
Plate 5 Some Pteroscion peli obtained …………………………………………… 30
Plate 6 Some Seriola dumerili obtained ………………………………………….. 30
Plate 7 Sampling point (A) ……………………………………………………….. 31
Plate 8 Sampling point (B) ……………………………………………………….. 32
Plate 9 Sampling point (C) ……………………………………………………….. 32
Plate 10 Total length of Seriola dumerili being taken …………………………… 33
vii

8. Plate 11 Sediment being air dried ………………………………………………… 34
Plate 12 some containers containing digested sample …………………………... 35
Plate 13 Water quality parameter being taken insutu ………………………... 36
LISTS OF FIGURES
FIGURES PAGE
Fig 3.1 Study area and its environs..............................................................................28
Fig 4.1 Variation in Cu, Pd, Cd and Zn concentration in the flesh of Pteroscion peli
from the Korle lagoon estuary.........................................................................41
Fig 4.2 Variation in Cu, Pb, Cd and Zn concentration in the flesh of Seriola dumerili
from the Korle lagoon estuary.........................................................................42
viii

9. CHAPTER ONE
1.0. INTRODUCTION
The coastline of Ghana is abundantly endowed with many lagoonal resources and is of
major significance for domestic, spiritual and economic activities. In recent times, the
coast of Ghana is encountering serious environmental challenges. These problems are in
response to rapid demographic changes and growth of industrial activities along the
coast. This development has coincided with the establishment of human settlements
which lack credible sanitary infrastructure to give adequate support to waste disposal
(Karikari, 2005). This has led to degradation of water quality leading to loss of the
ecological integrity of most lagoons.
Korle lagoon is one such lagoon in Accra, Ghana which used to support a vibrant
artisanal fishery with attendant socio-economic activities for the communities living
around the lagoon up to the 1980’s when uncontrolled pollution from domestic and
industrial sources severely impacted on the Lagoon’s fishery and nearly led to its
collapse. According to Entsua-Mensah et al. (2004), the Korle Lagoon estuary still
supports artisanal fisheries which play an important role in the economy of some coastal
inhabitants, especially during the off-season for marine fishing. The Lagoon also serves
as breeding grounds for some fish species.
Heavy metals are intrinsic, natural constituents of our environment. They are generally
present in small amounts in natural aquatic environments. Apart from the natural sources,
several anthropogenic activities also contribute to metal concentrations in the
environment (Woo, et al., 1993). An activity that massively contributes to the pollution
1

10. of the lagoon with heavy metal is the local and crude methods of recycling electronic
waste (e-waste) to retrieve its metallic components. According to Aanstoos et al (1998)
electronic waste consist of 32 different metals at different percentage mass. An
excessively high metal concentration in the sediments of Korle lagoon has been reported
(Greenpeace 2008).
Copper and Zinc were selected based their importance to living organisms. Lead and
Cadmium was selected base on their toxicity in small concentrations.
Different aquatic organisms often respond to external contamination in different ways,
where the quantity and form of the element in water, sediment, or food will determine the
degree of accumulation (Begum et al., 2009).
The degree of contamination depend on pollutant type, fish species, sampling location,
trophic level and their mode of feeding (Asuquo et al. 2004).
Species in relatively low trophic levels are exposed to comparatively lower heavy metal
concentration. Fishes in the upper food web position are prone to accumulate more heavy
metals through bio magnification (Al- Yousuf et al 2000) contamination, although plants
can accumulate metals in high levels (Peakall et al 2003).
1.1. Justification
2

11. The Korle Lagoon in Accra, Ghana, has become one of the most polluted water bodies on
earth. It is the principal outlet through which all major drainage channels in the city
empty their wastes into the sea. Large amounts of untreated industrial waste emptied into
surface drains has led to severe pollution in the lagoon and disrupted its natural ecology.
The increased levels of industrial activity and consumption by the urban population lead
to the generation of copious quantities of waste (Boadi & Kuitunen. 2002).
Agbogbloshie, a suburb of Ghana’s capital, Accra, and just adjacent the lagoon is a
known destination for legal and illegal electronic waste (e-waste) dumping from
industrialized nations, often referred to as a "digital dumping ground". Millions of tons of
e-waste are processed each year in the local recycling workshops. A study by Greenpeace
(2008) revealed excessively high metal concentrations in the soils of the open burning
grounds and in the sediments of the lagoon.
Contaminated sediments do not always remain at the bottom of a water body. Anything
that stirs up the water, such as dredging and upwelling, can resuspend sediments.
Resuspension may mean that all animals in the water, and not just the bottom-dwelling
organisms, will be directly exposed to toxic contaminants (Begum, et al., 2009).
Fishes often accumulate large amounts of these metals in polluted areas. They assimilate
these heavy metals through ingestion of suspended particulates, food materials and
sometimes by constant ion exchange process of dissolved metals across lipophilic
membranes like the gills and adsorption of dissolved metals on tissue and membrane
3

12. surfaces (Begum, et al., 2009). Bio magnification can result in fish at the top of food chain
containing hundreds more heavy metals than it appears in the water or in any single fish
they eat.
Seriola dumerili and Pteroscion peli are important fish species in the Korle lagoon
fishery and are in high demand by the inhabitants of Accra especially those around the
Korle lagoon. Inhabitants often prefer large sizes of Seriola dumerili and small sizes of
Pteroscion peli. Since these species are carnivores they could possibly accumulate heavy
metals which could be detrimental to those who consume them.
In small quantities, certain heavy metals are nutritionally essential for a healthy life.
Some of these are referred to as the trace elements (e.g., iron, copper, manganese, and
zinc). These elements, or some form of them, are commonly found naturally in
foodstuffs, in fruits and vegetables, and in commercially available multivitamin products
(International Occupational Safety and Health Information Centre, 1999) but high
quantities of these toxic metals may cause defects like memory loss, high blood pressure,
poor concentration, aggressive behaviour, sleeplessness and a number of other defects
(Aneum, 2010).
1.2. OBJECTIVES
4

13. Based on the above reasons the objectives of this study were:
• To assess the concentration of zinc, lead, copper and cadmium in the sediment and flesh
of Pteroscion peli and Seriola dumerili.
• To examine variations in heavy metal concentration in the flesh of the Pteroscion peli
and Seriola dumerili in relation to size.
5

14. CHAPTER 2
2.0. LITERATURE REVIEW
2.1. Global Water Pollution
Every day, 2 million tons of sewage, industrial and agricultural waste is discharged into
the world’s water (UN-WWAP, 2003), the equivalent of the weight of the entire human
population of 6.8 billion people. The UN estimates that the amount of wastewater
produced annually is about 1,500 km3, six times more water than exists in all the rivers
of the world (UN-WWAP, 2003). Lack of adequate sanitation contaminates water
courses worldwide and is one of the most significant forms of water pollution.
Worldwide, 2.5 billion people live without improved sanitation (UNICEF and WHO,
2008). Over 70% of these people, who lack sanitation, live in Asia. Sub-Saharan Africa is
slowest of the world’s regions in achieving improved sanitation: only 31 percent of
residents have access to improved sanitation in 2006. Eighteen percent of the world’s
population, or 1.2 billion people, defecate in the open. Open defecation significantly
compromises quality in nearby water bodies and poses an extreme human health risk
(UNICEF and WHO, 2008).
The effects of water pollution is said to be the leading cause of death for humans
across the globe, moreover, water pollution affects our oceans, lakes, rivers, and
drinking water, making it a widespread and global concern (Scipeeps, 2009). Since
the population of cities in the developing world are rising rapidly (Grobicki, 2001) and
in-order to meet the ever increasing demand for food, other services for human
6

15. development including rapid urbanization and industrial growth, many unplanned
interventions have been made in water bodies in many parts of the world (Vass, 2007).
Polluted water consists of Industrial discharged effluents, sewage water, rain water
pollution (Ashraf et al, 2010) and pollution by agriculture or households cause
damage to human health or the environment (European Public Health Alliance, 2009).
This water pollution affects the health and quality of soils and vegetation, (Carter, 1985).
Some water pollution effects are recognized immediately, whereas others don’t show
up for months or years (Ashraf et al, 2010). There has been widespread decline in
biological health in inland (non-coastal) waters. Globally, 24 percent of mammals and 12
percent of birds connected to inland waters are considered threatened (UN-WWAP,
2003).
In some regions, more than 50% of native freshwater fish species are at risk of extinction,
and nearly one-third of the world’s amphibians are at risk of extinction. Freshwater
ecosystems sustain a disproportionately large number of identified species, but are
increasingly threatened by a host of water quality problems (Vié et al, 2009).
Seventy percent of industrial wastes in developing countries are disposed of untreated
into waters where they contaminate existing water supplies, (UN-Water, 2009). Roughly
one unit of mercury is emitted into the environment for every unit of gold produced by
small-scale miners; a total of as much as 1000 tons of mercury is emitted each year
(UNEP/GRID-Arendal, 2009).
7

16. 2.1.1. Environmental Aquatic Pollution
The pressure of increasing population, growth of industries, urbanization, energy
intensive life style, loss of forest cover, lack of environmental awareness, lack of
implementation of environmental rules and regulations and environment improvement
plans, untreated effluent discharge from industries and municipalities, use of non-
biodegradable pesticides/fungicides/ herbicides/insecticides, use of chemical fertilizers
instead of organic manures, etc are causing water pollution. The pollutants from
industrial discharge and sewage besides finding their way to surface water reservoirs and
rivers are also percolating into the ground to pollute ground water sources (Trivedi,
2008).
The polluted water may have undesirable colour, odour, taste, turbidity, organic matter
contents, harmful chemical contents, toxic and heavy metals, pesticides, oily matters,
industrial waste products, radioactivity, high Total Dissolved Solids (TDS), acids,
alkalises domestic sewage content, virus, bacteria, protozoa, rotifers, worms, etc. The
organic content may be biodegradable or non-biodegradable. Pollution of surface waters
(rivers, lakes, and ponds), ground waters, and sea water are all harmful for human and
animal health. Pollution of the drinking water and that of food chain is by far the most
worry-some aspect (Kant, 2005).
Toxic chemical substances introduced into the environment may be transported by
the air, water and living organisms and may become a part of the natural
biogeochemical cycle and accumulate in the food chain (Gadzała-Kopciuch, 2004).
Some of the pollutants like lead (Pb), arsenic (As), mercury (Hg), chromium (Cr)
specially hexavalent chromium, nickel (Ni), barium (Ba), cadmium (Cd), cobalt (Co),
8

17. selenium (Se), vanadium (V), oils and grease, pesticides, etc are very harmful, toxic and
poisonous even in ppb (parts per billion) range (Lucky, 2002). There are some minerals
which are useful for human and animal health in small doses beyond which these are
toxic. Zinc (Zn), copper (Cu), iron (Fe), etc fall into this category. For agriculture, some
elements like zinc, copper, manganese (Mn), sulphur (S), iron, boron (B), together with
phosphates, nitrates, urea, potassium, etc are useful in prescribed quantities. There are
some compounds like cyanides, thiocyanides, phenolic compounds, fluorides, radioactive
substances, etc which are harmful for humans as well as animals (Kudesia, 2002).
Water bodies contaminated by heavy metals may lead to bioaccumulation in the food
chain of an estuarine environment. Such contaminants are transported from its sources
through river system and deposited downstream. Since most of the pollutants could be
mixed and become suspended solid and bottom sediment through sedimentation,
therefore estuary is a potential sink for these pollutants over a long period of time
(Morrisey et al., 2003).
2.2. Heavy Metals
Heavy metals are metals or, in some cases, metalloids which are stable and have a density
greater than 4.5 g/cm 3 and their compounds (UNECE, 1998).
Low concentration of metals in water might not necessary reflect that the area is pollution
free. The biotic life in such an area might have accumulated the metals from water from
time to time. Such a situation could be observed from the higher concentration of heavy
metals in the tissue of organisms found in the estuary (Abdullah, 2007).
9

18. Higher concentrations of heavy metals (such as Cd, Pb, Cu and Zn) in the sediment of an
estuary concur with the pattern of those metals found in the tissues of estuary organisms
(Abdullah, 2007).
2.2.1. Source of Heavy Metals
Heavy metals differ in their chemical properties, and are used widely in electronic
components, machinery and materials. Consequently, they are emitted to the environment
from a variety of anthropogenic sources to supplement natural background geochemical
sources. Some of the oldest cases of environmental pollution in the world were caused by
heavy metal extraction and use, for example, copper, mercury and lead mining, smelting
The amounts of most heavy metals deposited to the surface of the Earth are many times
greater than depositions from natural background sources. Combustion processes are the
most important sources of heavy metals, particularly, power generation, smelting,
incineration and the internal combustion engine (Battarbee, 1988).
Common Metals and their sources also include:
• Lead: leaded gasoline, tire wear, lubricating oil and grease, bearing wear
• Zinc: tire wear, motor oil, grease, brake emissions, corrosion of galvanized parts
• Copper: bearing wear, engine parts, brake emissions
• Cadmium: tire wear, fuel burning, batteries (Kiliç, 2011).
10

19. 2.2.2. Sediments and Heavy Metals in Estuaries
Estuaries are important zones of sediment transfer between fluvial and marine systems,
often forming sinks for sediment moving downstream, alongshore or landwards and
consequently for dissolved and particulate contaminants from recreational, farming,
manufacturing and extractive industries, both on land and offshore (Morrisey et al, 2003).
Heavy metals in sediments represent a combinational effect of chemical, biological and
physical processes occurring in fluvial, estuarine, and coastal environments. Surface
sediments integrate these changes that occur in the water column and act both as a
repository and source of suspended materials. Spatial variations of heavy metals in the
surface sediments are the results of these processes (Lin, et al, 2003).
Heavy metals generally exist in two phases in estuarine waters, i.e., in the dissolved
phase in the water column and in the particulate phase adsorbed on the sediments. The
behaviour of heavy metals in the aquatic environment is strongly influenced by
adsorption to organic and inorganic particles. The dissolved fraction of heavy metals may
be transported through the water column via the processes of advection and dispersion,
while the particulate fraction may be transported with the sediments, which are governed
by sediment dynamics. The partition of heavy metals between the dissolved and adsorbed
particulate phases depends on the physical and chemical characteristics of the suspended
particles as well as various ambient conditions, such as: salinity, pH, and the types and
concentrations of dissolved organic matter (Wu et al., 2005).
Fine sediments, acting as a source (or sink) for the organic chemical and heavy metals
entering (or leaving) the water column with sediments contaminated by the heavy metals,
11

20. pose a potential threat to the aquatic environment. Resuspension of contaminated bed
sediments caused by strong tidal currents may release a significant amount of heavy
metals into the water column, and this desorption of contaminants from their particulate
phase can have a pronounced impact on the aquatic environment and ecosystem (Zagar,
2006).
Although estuaries are sinks for contaminants from the terrestrial environment, there is
significant transport of marine material up-estuary as bed load sediment whilst fine-
grained terrestrial material may be transported seawards in suspension. Major movement
of contaminants from estuaries onto the continental shelf probably occurs only during
floods and storms and, in general, the impact on shelf seas is relatively minor and
confined to the coastal zone (Ridgway et al, 2000).
2.3. Some Common Heavy Metals
Several metals are found in the ecosystem in trace amounts and these metals are of great
importance to living organisms.
2.3.1. Copper
Copper exist in the natural water system either in the form as the cupric (Cu2+
) ion or
complexes with inorganic anions or organic ligands or as a suspended particle when
present as precipitates or absorbed to organic matter ( Mance et al 1984). It can also be
adsorbed to bottom sediments or exist as settled precipitate. The concentration of each of
these forms depends on complex interaction of many variables including the
12

21. concentration of copper and hardness, alkalinity, salinity, pH and concentration of
bicarbonate, bicarbonate sulphide, phosphate organic ligands and other metal ions.
Copper is an essential element to all living organisms, and because of that both
deficiency and excess have consequence for the integrity of biochemical functions. The
main biological role of copper is as an ingredient, normally in the prosthetic group, of
oxidizing enzymes which are important in oxidation-reduction processes (Moolenaar,
1998).
Complexes formed by copper are more stable than other metals such as cadmium, lead
and zinc. The high concentration of particulate matter in most estuaries will facilitate
removal of copper from solution by adsorption to suspended particles which in turn may
be deposited and accumulate in sediments.
Estuarine sediments are thought to be the most important depositional site for particulate
copper transported from rivers, although remobilization may occur when sediments is
disturbed. The remaining dissolve copper in the water column is likely to be present
either as an organic complex or as a cupric ion. Copper in the cupric form is the most bio
available (Grimwood, 1997). Copper is readily accumulated by plants and animals.
Whole –body concentration tends to decrease with increasing trophic level. it is also
regulated or immobilized in many species and is not biomagnified in food chains to any
significant extent (CCREM.,1987).
2.3.2. Lead
13

22. Lead is a micro element naturally present in trace amounts in all biological materials,
thus, in soil, water, plants and animals. It has no physiological function in the organism.
Some sources of lead pollution are those emanating from anthropogenic activities such as
smelting works, application of wastewater treatment sludges to soil, transportation and
also from surface runoffs. Lead pollution sources can also be extended to paints, lead
wastes, cell batteries and lead solders and most do enter the organism through
contaminated food and air (Boakye, 2011). The maximum acceptable toxicant limit for
inorganic lead has been determined for several species under different conditions and
results range from 0.04 mg l-1 to 0.198 mg l-1. The acute toxicity of lead is highly
dependent on the presence of other ions in solution, and the measurement of dissolved
lead in toxicity tests is essential for a realistic result. Organic compounds of lead are more
toxic to fish than inorganic lead salts (WHO, 1995). Lead accumulates in sediments and
can pose a hazard to sediment-dwelling organisms at concentrations above 30.2 mg kg-1,
(according to Canadian Interim Marine Sediment Quality Guidelines).
In aquatic ecosystems, uptake by primary producers and consumers seems to be
determined by the bioavailability of the lead. The uptake and accumulation of lead by
aquatic organisms from water and sediment are influenced by various environmental
factors, such as temperature, salinity, and pH, as well as humic and alginic acid content.
In many organisms, it is unclear whether lead is adsorbed onto the organism or actually
taken up. Consumers take up lead from their contaminated food, often to high
concentrations, but without biomagnifications (WHO 1995).
Lead uptake by fish reaches equilibrium only after a number of weeks of exposure. Lead
is accumulated mostly in gill, liver, kidney, and bone. Fish eggs show increasing lead
14

23. levels with increased exposure concentration, and there are indications that lead is present
on the egg surface but not accumulated in the embryo. Also young stages of fish are more
susceptible to lead than adults or eggs. Typical symptoms of lead toxicity include spinal
deformity and blackening of the caudal region. In contrast to inorganic lead compounds,
tetra alkyl lead is rapidly taken up by fish and rapidly eliminated after the end of the
exposure (WHO 1995).
2.3.3. Zinc
Zinc is one of the most ubiquitous and mobile heavy metals and is transported in natural
waters in both dissolved forms and associated with suspended particles (Mance et al,
1989). In estuaries where concentration of suspended particles is greater, zinc
accumulates particularly in anaerobic sediments. A greater proportion is adsorbed to the
suspended particles (CCREM, 1987).
In low salinity areas of estuaries, zinc can be mobilized on particles by microbial
degradation of organic matter and displacement by calcium and magnesium. In high
turbidity, greater levels of zinc associated with suspended sediments is deposited with
flocculated particles where it can and where it can particularly accumulate in anaerobic
sediments. The toxicity and bioaccumulation of zinc is greater at lower salinity (Hunt et
al, 1992) and invertebrates generally have high concentrations than fish species. Zinc
accumulates in sediments and can pose hazard to sediment dwelling organisms at
concentration above 125mg/kg.
Zinc is an essential element for many marine organisms and as such is readily bio
accumulated. Several species of crustaceans are able to regulate the uptake of zinc but at
15

24. higher concentration, this process appears to breakdown leading to an influx of zinc also
according to (NAS, 1979), gills of fish are physically damaged by high concentrations of
zinc. Organisms can take up zinc which is reflected in the bioaccumulation factor but
may not reflect in the tissue (Hunt et al 1992).
2.3.4. Cadmium
Cadmium is a relatively volatile element not essential to plants, animals and humans. Its
presence in organisms is unwanted and harmful. An increased level of cadmium in the
air, water and soil increases its uptake by organisms (Järup, 2003). Cadmium uptake from
water by aquatic organisms is extremely variable and depends on the species and various
environmental conditions, such as water hardness (notably the calcium ion and zinc
concentration), salinity, temperature, pH, and organic matter content. The majority of
chelating agents decrease cadmium uptake but some, such as dithiocarbamates and
xanthates, increase uptake. Increasing temperature increases the uptake and toxic impact,
whereas increasing salinity or water hardness decreases them. Acute lethal effects for
marine organisms have been noted as low as 16 µg l-1 (WHO ,1992). Cadmium is
toxic because it has some similarities with zinc that is an essential element; it is a typical
example of a cumulative poison (Järup, 2003). Cadmium is toxic to a wide range of
micro-organisms. The presence of sediment, high concentrations of dissolved salts or
organic matter all reduces the toxic impact. The main effect is on growth and replication.
An increase in toxicity as temperature increases and salinity decreases has been noted.
This implies that the same cadmium concentration may have the potential to cause
greater toxicity to estuarine rather than to marine species. At low concentrations (10
16

25. µg cadmium l-1), cadmium inhibits ion transport systems and induces
metallothionein synthesis (< 1 &micro;g cadmium l-1) in freshwater fish. Cadmium
toxicity has been found to be variable in fish, with salmonids being particularly
susceptible to cadmium. Sub-lethal effects in fish, notably malformation of the spine,
have been reported. The most susceptible life-stages are the embryo and early larva,
while eggs are the least susceptible. There is no consistent interaction between cadmium
and zinc in fish (WHO 1992). Cadmium bio accumulates in organisms with the main
uptake routes being dissolved cadmium from the water column and cadmium associated
with prey items.
2.4. Bio-Importance of Heavy Metals to Humans
Some heavy metals (like Zinc and Copper) have been reported to be of bio-importance to
man and their daily medicinal and dietary allowances. Their tolerance limits in drinking
and potable waters have also been reported, However, some others (like Cadmium and
Lead, ) have been reported to have no known bio-importance in human biochemistry and
physiology and consumption even at very low concentrations can be toxic (Holum, 1983;
Fosmire, 1990; McCluggage, 1991; Ferner, 2001; European Union, 2002; Nolan, 2003;
Young, 2005). Even for those that have bio-importance, dietary intakes have to be
maintained at regulatory limits, as excesses will result in poisoning or toxicity, which is
evident by certain reported medical symptoms that are clinically diagnosable (Fosmire,
1990; Nolan, 2003; Young, 2005). Zinc is a ‘masculine’ element that balances copper in
the body, and is essential for male reproductive activity (Nolan, 2003). It serves as a co-
factor for dehydrogenating enzymes and in carbonic anhydrase (Holum, 1983). Zinc
17

26. deficiency causes anaemia and retardation of growth and development (McCluggage,
1991). Calcium is a very vital element in human metabolism. It is the chief element in the
production of very strong bones and teeth in mammals. Its tolerance limit is high relative
to other bio-useful metals, that is, at 50 mg/l of drinking water .The daily dietary
requirement of calcium soars at the highest across both sexes and all ages of humans
accommodated at higher doses in the body because its concentration in the blood is well
regulated by thyrocalcitonin and parathormone hormones (Holum, 1983). Lead and
cadmium have been reported not to have any known function in human biochemistry or
physiology, and do not occur naturally in living organisms (Lenntech, 2004). Hence
dietary intakes of these metals, even at very low concentrations can be very harmful
because they bio accumulate.
2.4.1. Effect of bioaccumulation on humans
The bio toxic effects of heavy metals refer to the harmful effects of heavy metals to the
body when consumed above the bio-recommended limits. Although individual metals
exhibit specific signs of their toxicity, the following have been reported as general signs
associated with cadmium, lead, zinc, and copper poisoning: gastrointestinal disorders,
diarrhoea, stomatitis, tremor, hemoglobinuria causing a rust–red colour to stool, ataxia,
paralysis, vomiting and convulsion, depression, and pneumonia when volatile vapours
and fumes are inhaled (McCluggage, 1991). The nature of effects could be toxic (acute,
chronic or sub-chronic), neurotoxin, carcinogenic, mutagenic or teratogenic. Cadmium is
toxic at extremely low levels. In humans, long term exposure results in renal dysfunction,
characterized by tubular proteinuria. High exposure can lead to obstructive lung disease,
18

27. cadmium pneumonitis, resulting from inhaled dusts and fumes. It is characterized by
chest pain, cough with foamy and bloody sputum, and death of the lining of the lung
tissues because of excessive accumulation of watery fluids. Cadmium is also associated
with bone defects, viz; osteomalacia, osteoporosis and spontaneous fractures, increased
blood pressure and myocardic dysfunctions. Depending on the severity of exposure, the
symptoms of effects include nausea, vomiting, abdominal cramps, dyspnea and muscular
weakness. Severe exposure may result in pulmonary oedema and death. Pulmonary
effects (emphysema, bronchiolitis and alveolitis) and renal effects may occur following
subchronic inhalation exposure to cadmium and its compounds (McCluggage, 1991;
INECAR, 2000; European Union, 2002; Young, 2005).
Lead is the most significant toxin of the heavy metals, and the inorganic forms are
absorbed through ingestion by food and water, and inhalation (Ferner, 2001). A notably
serious effect of lead toxicity is its teratogenic effect. Lead poisoning also causes
inhibition of the synthesis of haemoglobin; dysfunctions in the kidneys, joints and
reproductive systems, cardiovascular system and acute and chronic damage to the central
nervous system (CNS) and peripheral nervous system (PNS), (Ogwuebgu and Muhanga,
2005). Other effects include damage to the gastrointestinal tract (GIT) and urinary tract
resulting in bloody urine, neurological disorder and can cause severe and permanent brain
damage. While inorganic forms of lead, typically affect the CNS, PNS, GIT and other bio
systems, organic forms predominantly affect the CNS (McCluggage, 1991; INECAR,
2000; Ferner, 2001; Lenntech, 2004). Lead affects children by leading to the poor
development of the grey matter of the brain, thereby resulting in poor intelligence
19

28. quotient (IQ) (Udedi, 2003). Its absorption in the body is enhanced by Ca and Zn
deficiencies. Acute and chronic effects of lead result in psychosis.
Zinc has been reported to cause the same signs of illness as does lead, and can easily be
mistakenly diagnosed as lead poisoning (McCluggage, 1991). Zinc is considered to be
relatively non-toxic, especially if taken orally. However, excess amount can cause system
dysfunctions that result in impairment of growth and reproduction (INECAR, 2000;
Nolan, 2003). The clinical signs of zinc toxicities have been reported as vomiting,
diarrhoea, bloody urine, icterus (yellow mucus membrane), liver failure, kidney failure
and anaemia (Fosmire, 1990).
2.5. Lagoon Pollution in Ghana
Presently, Ghana is dealing with the rate of urban periphery settlements which is as a
result of the massive migration of the rural inhabitants to the cities, especially to Accra.
Unfortunately persons in these settlements often lack essential social amenities,
especially those related to sanitation, resulting in heavy environmental pollution. The
contamination of lagoons with heavy metals is a major source of concern since it is a
habitat for fish and other aquatic organisms such as mussels, oysters, prawns and lobsters
which are major sources of protein for most people in Ghana. Heavy metals released into
the environment find their way into aquatic systems as a result of direct input,
atmospheric deposition and surface runoffs. Fish species can accumulate these heavy
metals in their tissues at concentrations greater than the ambient water and pose a health
threat to humans who consume them (Armah, 2007).
20

29. Natural waters therefore become the key environmental component that suffers massively
from such pollution and this is the current situation epitomized by the Korle lagoon in
Accra. Some years ago the Korle lagoon was of economic importance to the country of
which some were able to reach it outside borders. Some of which were salt, fish and
wood (Armah, 2007).
2.6. State of the Korle lagoon
The Korle lagoon, which is a major run-off water receptacle and a point source of
pollution into the Gulf of Guinea, has been negatively impacted by the uncontrolled
domestic and industrial pollution. Previous water quality surveys indicated that the Korle
lagoon is moderate to grossly polluted water body as evidenced by the physical, chemical
and bacteriological characteristics which can be traced to discharges of domestic and
industrial effluents from inland as well as to the operations of the sewage outfall in the
vicinity of the lagoon’s entrance (Karikari et al, 2007). Up to the 1950s, the Korle
Lagoon supported a thriving fishery, but presently it supports only a few fish species
which include Seriola dumerili and Pteroscion peli, are restricted to its estuary (Biney
and Amuzu, 1995).
The increasing pollution of Korle Lagoon is as a result of the rapid urbanization of Accra.
This has been unaccompanied by a significant increase in sanitation facilities. The
process has been assisted by rapid industrialization without regard for environmental
safety. Rapid population growth, enhanced by the facilities and job opportunities,
continues to draw people into Accra. This has resulted in considerable stress on the
21

30. already inadequate urban facilities including the housing and basic sanitation amenities.
This situation has led to the development of slums and shantytowns, and the consequent
degradation of the urban environment. With little equipment to manage the refuse,
garbage is collected only in high-income areas (Doe, 2000).
The remaining areas disposed of their garbage in public containers, in open spaces,
streams and drainage systems. The catchment area is surrounded by shantytowns,
including Korle Gonno, Korle Dudor, Adadinkpo and James Town, among many others.
Prominent among these slums is Sodom and Gomorra (Old Fadama), a growing squatter
settlement. The site exhibits poor housing conditions and consists mainly of wooden
shacks (Doe, 2000). There are no sanitation facilities, and people defecate directly into
the lagoon with all kinds of waste being disposed of into the water body.
2.6.1. Heavy metal sources to the lagoon
A major activity that massively contributes to the pollution of the lagoon is the local and
crude methods of recycling electronic waste (e-waste) to retrieve the metallic
components. Agbogbloshie, a suburb of Ghana’s capital, Accra, and just adjacent the
lagoon is a known destination for legal and illegal of electronic waste (e-waste) from
industrialized nations. Often referred to as a "digital dumping ground", millions of tons of
e-waste are processed each year in the local recycling workshops. At these workshops, e-
waste is recycled with virtually no regulations, and primarily involves manual
disassembly of the obsolete electronic products and open burning to isolate copper and
other valuable metals from plastics.
22

31. Other sources of heavy metals into the Lagoon can be traced to effluent discharged from
domestic and industrial activities. According to Boadi and Kuitunen (2002) and Agodzo
et al, (2003), approximately 60% of the domestic and industrial waste from Accra, the
capital of Ghana, with a population of approximately 4.0 million people, flows into the
Lagoon. Other major potential sources of heavy metal pollution in the Lagoon are the
numerous local metal smelting industries and the small garages and workshops located
within in the vicinity of the Lagoon. Another major source of pollution in the Lagoon is
the Odaw River, a major inlet of the Korle Lagoon. The Odaw River drains the high
density low income areas of Accra and has a large concentration of industries including
breweries, several textile factories and vehicle repair workshops in its catchment.
2.6.2. Effect of Korle lagoon pollution
Severe pollution of the lagoon has resulted in the reduction of aquatic invertebrates and
the complete disappearance of some species from the lagoon’s environs. The break in the
food chain has resulted in the near extinction of both resident and non-resident birds,
which feed and roost in the mangroves and mudflats along the lagoon. The pollution has
also resulted in a fowl stench, which in itself is a disincentive for tourism development.
Domestic and industrial pollutants have contributed to increased biochemical oxygen
demand and concentration of toxic chemicals in the water body (Biney and Amuzu,
1995).
2.6.3. Activities at the estuary
23

32. Presently however, beach seining and other fishing activities take place at the estuary of
the lagoon and within 500 m offshore and the harvested fish are usually sold to local food
vendors and also to satisfy domestic protein requirements. Although fish from the
estuary of the lagoon are believed to be unwholesome for human consumption, very little
research has been carried out to determine the levels of contaminants in the flesh of the
fish harvested from the Lagoon (Entsua-Mensah, 2004).
2.7. Fish Species
There is a definite pattern in the distribution of fish species on the continental shelf
(Longhurst, 1965). The available data indicate that the distribution of a number of species
is limited by the depth of the thermocline and is influenced by the type of bottom deposits
(sand and silts), and the depths on the continental shelf, the slope of which is variable.
There are discrete ecological fish communities, each of which is fairly homogeneous.
However, there is also ecological and micro geographical heterogeneity of fish
communities. Besides, migration of species from the estuaries and creeks to the open
shelf areas and vice versa is known to occur.
The following fish communities are exploited by the artisanal fishing units:
i. the estuarine and creek sciaenid sub-community,
ii. the offshore suprathermoclinal sciaenid sub-community (on soft deposits),
iii. the sparid sub-community (on sandy) (FAO, 1981).
24

33. 2.7.1. Seriola spp
The genus Seriola is of the family Carangidae, order Perciformes, and class
Actinopterygii. Three species of the genus Seriola are caught at the estuary of the Korle
lagoon with the dominant species being Seriola dumerili.
The greater amberjack, S. dumerili, is a cosmopolitan species, found in warm waters all
over the world. Its main morphological characteristics are the elongated, fusiform and
slightly laterally compressed body, covered with small scales (cycloids). Their color is
yellow-green in juveniles; in adults it is blue or olivaceous dorsally and silvery to white
on the sides and belly. S. dumerili is a multiple spawning fish, and it may release several
batches of eggs during the same spawning season. The ovary type in this group is
synchronous: at least two size groups of oocytes are present at the same time (Grau
1992). This species is gonochoric without sexual dimorphism, and both sexes are
separated. According to Micale et al. (1993), maturity occurs at three years of age but
functional breeders are 4 and 5 years old for males and females respectively. Marino et
al. (1995) reported the first reproductive season for this species to be at 4 years of age for
both sexes, even though 40% of males are sexually mature at 3 years of age.
Japanese amberjack (S. quinqueradiata) are present in the Western Central Pacific
Ocean from Japan and the eastern Korean Peninsula to the Hawaiian Islands. This species
reaches a maximum size of 150 cm TL (male/unsexed) and a maximum weight of 40 kg.
It shows asynchronous oocyte development.
Yellowtail amberjack (Seriola lalandi) are present in Atlantic, Pacific and Western Indian
Oceans. It is considered a circumglobal species, supporting commercial and recreational
25

34. fisheries worldwide. This species is a spring-summer spawner, with a multiple group
synchronous oocyte development and, like the greater amberjack (S. dumerili), has the
capacity for multiple spawning within a reproductive season. The smallest size at which
females caught in New Zealand matured was 775 mm FL; 50% reached sexual maturity
at 944 mm, while all were mature at 1 275 mm. McGregor (1995) reported maturity at
580-670 mm. In Australia, according to Gillanders, et al (1999), mature females of this
species appeared at 698 mm (3 years) reaching 50% at 834 mm (4-5 years). The
differences in size between these 2 populations could be attributed to different rearing
conditions.
2.7.2. Pteroscion peli
Belongs to the Class Actinopterygii (ray-finned fishes) order perciformes (Perch-likes) >
family sciaenidae (Drums or croakers). Pteroscion peli occurs only along the West coast
of Africa, from Senegal to Angola, where it is found in mid waters as well as on mud,
sandy mud bottoms in coastal waters and also occurs seasonally in brackish water areas.
Its depth distribution extends from the shoreline to 200 m but the species prefers waters
of less than 50 m and is one of the most abundant sciaenids in shallower waters and feeds
on fish, cephalopods, shrimps and annelids (FAO 1986).
26

35. CHAPTER THREE
3.0. METHODOLOGY
3.1. Description of the study area
The Korle lagoon is a coastal wetland that joins the Gulf of Guinea at a point near Korle
Gonno; a suburb of Accra (Grant, 2006). It serves as the major floodwater conduit for the
Accra Metropolitan Assembly (Fig 3.1), the lagoon is estimated to drain a total catchment
area of 400 km2
(Karikari et al, 1998). The major hydrological input includes the Odaw
River, two huge drains that border the lagoon, and rainfall including runoff. A mixture of
land uses characterizes the areas adjacent to the lagoon (Boadi and Kuitunen, 2002).
Fig 3.1 Korle lagoon and its environs (IMDC, 2011)
27

36. 3.2. Sample collection
Fish samples were obtained from fishers (Plate 3, 4) at the estuary of the Lagoon and
transported on ice in an insulated chest (Plate 1, 2).
Plate 1 Pteroscion peli from the Korle lagoon Estuary
Plate 2 Seriola dumerili from the Korle lagoon Estuary
A total of 8 samples (Plate 5, 6) were obtained monthly for each species over the four
months period. Samples from each species were categorized into two classes based on the
sizes obtained for each; Pteroscion peli (Small ≤14cm and large ≥ 15cm) and Seriola
dumerili (Small ≤24cm and large ≥25 cm) and were stored in a deep freezer prior to the
heavy metal analysis.
28

37. Plate 3 Beach Seining at the Korle lagoon estuary Plate 4 Obtaining samples from fishers
Plate 5 Some Pteroscion peli obtained Plate 6 Some Seriola dumerili obtained
Three sediment sampling sites were selected from site A, site B and site C as shown in
The sediment sample was taken from each site and was divided into three to ensure
accuracy in the result for each site sampled. This was done for the four months study
period; October 2011 to January 2012. The Ekman grab was used in collecting the
sediments samples. At site B and C the Ekman grab was mounted in a boat, after
29

38. releasing the instrument to the bottom the boat owner dived to trip the over lapping
spring loaded with scoop, the depth of both portion could be between 1 to 4 meters whilst
at point C samples were taken by walking into the water to points where the water
reached the knee and with the Ekman grab sediments were collected. Samples were
stored in plastic bottles and packaged in plastic bags and were kept in a cool, dry and
ventilated room prior to heavy metal analysis.
Sampling point (A) is the area that receives frequent sea water at both low tides and high
tides with no rock deposited on both side (Plate 7).
Plate 7 Sampling point (A)
Sampling point (B) is the area affected by the influx of both fresh water and sea water
and rocks are deposited on the right side of the curved channel (Plate 8).
30

39. Plate 8 Sampling point (B)
Sampling point (C) is the area that receives fresh water frequently than sea water and also
joins B in a slightly curved channel with rocks deposited on both sides (Plate 9).
Plate 9 Sampling point (C)
3.3. Heavy Metal Analysis
In order to free bonded heavy metals in the flesh of Pteroscion peli, Seriola dumerili and
sediments, wet di-acid digestion was done. All procedures for the analyses were based on
the Association of Analytical Chemist (AOAC 2003) protocol.
31

40. 3.3.1. Sample Digestion
Fish and sediments samples acquired were digested at the same time. Sample digestion is
the removal of organic materials and the conversion of metals present into soluble forms.
3.3.2 Fish digestion
The total length (Plate 10) and body weight of the fish samples after defrosting were
measured with a centimetre rule and weighed with an electric scale (Sartorius model, BP
6100) and labelled after identification. Small part (5grams) of the flesh from its side were
removed and chopped with the aid of stainless steel dissection instruments, while wearing
surgical gloves. After, flesh samples were then digested with a di- acid mixture, (nitric
acid, and perchloric acid in a ratio of 9: 4).
Plate 10 Total length of Seriola dumerili being taken
One gram of the chopped flesh samples was separately taken and placed in a 100ml
volumetric flask. Ten millilitres of di acid mixture was added. The content was mixed by
swirling in the volumetric flask. The flask was then placed on a hotplate in a fume hood
and heated starting at 90o
C and raised to 200o
C. Heating continued until the production of
a red NO2 fume ceases. The contents were further heated until the volume was reduced to
3-4ml and became colourless without being dry. It was made to cool to room
32

41. temperature. The volume was made up with distilled water and filtered with a Whatmann
filter paper. The filtrate was then diluted to 50ml mark in a volumetric flask with double
distilled water. It was then poured into small containers. The containers containing the
digested samples were kept at 4˚c in a refrigerator prior to heavy metal analysis (Plate
12).
3.3.2. Sediment digestion
Sediment samples were labelled (according to their location) on the field and air dried at
room temperature. Sediments were dried on a plastic sheet (Plate 11).
Plate 11 Sediments being air dried at room temperature
The dried materials were grounded to pass through a 63µm sieve and stored in plastic
bottles. Digestion was done for the sediments as it was done for the fish flesh samples
above at the Faculty of Renewable Natural Resources.
33

42. Plate 12 Some containers containing digested samples
3.3.3. Determination of heavy metal concentration
Heavy metal analysis was done at the Anglo Gold Ashanti Laboratory. The
concentrations of copper, cadmium, lead, and zinc, were determined with the aid of flame
Atomic Absorption Spectroscopy, (AAS) (SpectrAA 220 model).
A blank solution of the di-acid and distilled water used which contained no analyte
element was made and after, a series of calibrated solutions of the di acid and distilled
water containing known amounts of analyte element (the standards) were also made. The
blank and standards were atomized in turn, with their respective responds measured.
Graph of both responses were plotted. The digested samples were then atomized and their
response measured. The concentrations of heavy metal in the sample were known by the
calibration and the absorbance obtained for the unknown.
34

43. All samples were accompanied by blanks at a rate of one blank per 20 samples. Replicate
analyses were conducted for all the samples to evaluate the precision of the analytical
technique. The results were expressed as total concentration (μg/g wet weight (ww).
3.3.4. Measurement of Physicochemical Water Parameters
Monthly measurement of temperature, salinity, pH, total dissolved solids (TDS),
conductivity and dissolved oxygen (DO) of the Korle Lagoon were taken between the
hours of 7am-10am, using a multi-parameter probe at the 3 sampling site over the four
months period -(YSI 550A model)(Plate 13).
Plate 13 Water Quality parameter been taken insitu
35

44. CHAPTER FOUR
4.0. RESULTS
4.1. Heavy metal concentrations in Sediment Samples
Copper concentration s were consistently fluctuating over the period and ranged between
4.38 μg/g ww to 5.90 μg/g ww from November 2011 to January 2012. A mean
concentration of 5.12 μg/g ww was recorded for the estuary over the four month period.
Lead concentration increased drastically from a mean value of 2.80 μg/g ww in October
to 39.20 μg/g ww in December 2011. A decrease in the concentration of lead was
recorded for January 2012.
Zinc ranged from 9.46 μg/g ww to 14.66 μg/g ww but this decrease was inconsistent as
concentration declined from 12.44 μg/g ww in November 2011 to 9.46 μg/g ww in
December 2011.
Cadmium concentration fluctuated over the period with highest concentration of 2.50
μg/g ww recorded in December 2011.Heavy metal levels in sediment over the period
ranked in the following order: Pb > Zn >Cu >Cd.
The monthly heavy metal concentrations of the four metals in the sediments of the Korle
lagoon estuary are shown in Table 4.1.
36

45. Table 4.1. Copper (Cu), Lead (Pb), Zinc (Zn) and Cadmium (Cd) concentration (μg/g
ww) in the sediment from the Korle lagoon Estuary.
Month n Cu Pb Zn Cd
October 9 4.41±0.15 2.80±0.96 12.21±4.28 2.33±0.25
November 9 4.38±0.39 2.86±1.49 12.44±3.62 2.26±0.30
December 9 5.80±0.02 39.20±0.46 9.46±0.88 2.50±0.10
January 9 5.90±0.08 38.36±1.69 14.66±0.05 2.23±1.00
Mean 5.12±0.16 20.80±1.15 12.19±2.20 2.33±0.41
NOAA (1995)
ERL 34.00 46.70 150.00 1.20
ERM 270.00 218.00 410.00 9.60
National Oceanic and Atmospheric Administration (NOAA), Effect Range low (ERL),
Effect Range Medium (ERM)
Values are mean± SD, n= number of samples.
4.2. Heavy metal concentrations in Pteroscion peli
Mean concentration of copper in Pteroscion peli over the sampled period was 5.11 μg/g
ww. Copper (Cu) levels increased between 2.83 μg/g ww in November 2011 to 7.65 μg/g
ww January 2012. In October 2011 concentration declined from 3.02 μg/g ww to 2.02
μg/g ww in November 2011. A mean lead (Pb) concentration of 2.73 μg/g ww was
recorded over the study period. An increase and decrease in concentration alternated over
the sampling period. Cadmium (Cd) concentration consistently increased from 1.48 μg/g
ww to 2.91 μg/g ww over the study period. Zinc (Zn) concentration increased from
November 2011 to January 2011 with values ranging between 13.58 μg/g ww to 23.11
37

46. μg/g ww for both months respectively. Between October 2011 and November 2011
concentration dropped from 14.09 μg/g ww to 13.58 μg/g ww. A mean concentration of
16.41 μg/g ww was recorded over the study period. Mean ± standard deviation of Cu, Pb,
Zn and Cd concentrations (μg/g ww) in the flesh of Pteroscion peli from the Korle
lagoon estuary from October 2011 to January 2012 is presented in Table 4.2.
Table 4.2. Heavy metal concentrations (μg/g ww) in the flesh of Pteroscion peli from
the Korle lagoon estuary
Month n Cu Pb Cd Zn
October 8 3.02 ± 1.20 2.62±1.1.83 1.48± 0.25 14.09±2.80
November 8 2.83 ± 0.42 2.87 ±1.80 1.51±0.29 13.58±1.97
December 8 6.92±0.91 2.51±0.45 2.81±0.22 14.86±4.27
January 8 7.65±0.93 2.95±0.34 2.91±0.15 23.11±6.99
Mean 5.11±0.86 2.73±1.10 2.17±0.22 16.41±4.00
WHO (1983) 10 2.0 2.0 1000
WHO (2005) - 0.5 0.5 1000
World Health Organization (WHO)
Values are mean± SD, n= number of samples
4.3. Heavy metal concentration in Seriola dumerili
38

47. Concentration trend observed in Seriola dumerili varied to that of Pteroscion peli.
Copper (Cu) concentration increased from November 2011 to January 2012 from 3.36
μg/g ww to 6.14 μg/g ww. A mean concentration of 4.43 μg/g ww was recorded over the
period.
Lead (Pb) concentrations over the period fluctuated between 2.07 μg/g ww in December
2011 to 3.01 μg/g ww in November 2011. A decrease in concentration was observed
from October 2011 to November 2011 and that of November 2011 to December 2011.A
mean concentration of 2.54 μg/g ww was recorded over the period.
Cadmium (Cd) level of 1.75 μg/g ww was recorded as the mean concentration over the
sampling period. Cadmium levels in Seriola dumerili were inconsistent over the study
period between 1.35 μg/g ww to 2.95 μg/g ww.
Zinc (Zn) concentrations increased from November 2011 to January 2012 with its level
increasing from 13.43 μg/g ww to 14.98 μg/g ww respectively. A mean concentration of
13.90 μg/g ww was recorded over the study period. Cu, Pb, Zn and Cd concentrations
(μg/g ww) in the flesh of Seriola dumerili from the Korle lagoon estuary is presented in
Table 4.3.
Table 4.3. Heavy metal concentrations (μg/g ww) in the flesh of Seriola dumerili from
the Korle lagoon estuary
39

48. Month n Cu Pb Cd Zn
October 8 3.38 ± 0.76 2.90 ± 2.0 1.42 ± 0.31 13.45 ± 6.26
November 8 3.36 ± 0.32 3.01 ± 2.07 1.35 ± 0.29 13.43 ± 6.34
December 8 4.85±2.32 2.07±0.30 2.31±1.20 13.76±6.04
January 8 6.14±1.52 2.20±0.59 2.95±0.43 14.98±4.66
Mean 4.43 ± 0.87 2.54 ± 0.92 2.03 ± 0.43 13.90 ± 0.78
WHO (1983) 10 2.0 2.0 1000
WHO (2005) - 0.5 0.5 1000
World Health Organization (WHO)
Values are mean± SD, n=number of samples
4.4. Heavy metals in the flesh of P. peli and the S. dumerili in relation to sizes
In order to examine variations in heavy metal concentration in the flesh of the two fish
species in relation to size, a plot of total accumulation versus size were carried out for the
two fish species (Fig 4.1 and 4.2).
4.4.1. Pteroscion peli
40

49. Heavy metal concentration in relation to size of Pteroscion peli increased with increase in
size for October 2011 and December 2011, even though for November 2011, zinc
concentration in Small Pteroscion was higher than that of large size.
In January 2012, copper and zinc concentrations increased in small Pteroscion peli than
in large size Pteroscion peli. Lead concentration in December 2011 was relatively higher
in the small fishes than in large samples (Fig 4.1 below).
Fig 4.1 Variations in Cu, Pb, Cd and Zn concentrations in the flesh of Pteroscion peli in
relation to body size (Small ≤14cm , Large ≥ 15cm)
4.4.2. Seriola dumerili
41

50. Heavy metal concentration in October 2012 and November 2012 increased with increase
in size as large size Seriola dumerili recorded higher levels than smaller Seriola dumerili.
On the other hand, small fish size fishes had higher concentration of copper and zinc for
December 2011 and January 2012. Lead concentrations in December 2011 were high in
large Seriola dumerili than in small once.
Fig 4.2.Variations in Cu, Pb, Cd and Zn concentrations in the flesh of Seriola dumerili in
relation to body size (Small ≤24cm, large ≥25 cm)
42

51. 4.5. Physicochemical Parameters of the Korle lagoon
Physicochemical parameters for the four months (October 2011 to January 2012)
sampling period was relatively uniform as shown in Table 4.4.
Temperature conditions in the lagoon ranged from 26.60°C to 29.10 °C over the period, a
consistent increase in temperature from November 2011 to January 2012 was recorded
Dissolve oxygen levels in the estuary was fairly constant over the sampling period even
though some portions of the estuary recorded very low oxygen levels. pH level over the
sampling period was relatively neutral. A high conductivity of 3901 mg/l was recorded in
January 2012. Salinity levels were low over the sampling months and were relatively
similar for the sampling months. A Total Dissolve Solid value of 1991 μs/cm was
recorded in December and was the highest over the study period.
Table 4.4. The physicochemical parameters of the Korle Lagoon from October, 2011 –
January, 2012
Parameter n October November December January
Temperature (°C) 3 26.81±0.59 26.60±0.80 29.10±1.10 28.50±0.10
DO (mg/l) 3 6.10±1.10 6.00±0.41 5.98±0.04 6.00±1.30
TDS ( μs/cm) 3 1748±397.93 1553±495.62 1991±0.05 1901±1.42
Salinity (ppm) 3 15.05± 0.41 14.77± 1.80 16.01± 0.01 15.98± 1.03
Conductivity (mg/l) 3 3588±553.65 3381±158.04 3008±0.01 3901±1.07
pH 3 7.30±0.30 7.16±0.24 7.07±0.86 7.18±1.05
Total Dissolve Solids (TDS), Dissolved Oxygen (DO),
Values are mean± SD, n=number of data recorded
43

52. CHAPTER FIVE
5.0. DISCUSSION
5.1. Heavy Metal Concentration in Sediments
Heavy metals in sediments may represent a combinational effect of chemical, biological
and physical processes occurring in the fluvial, estuarine, and coastal environments.
Fluctuations in the concentrations of heavy metals in the sediment of the Korle lagoon
estuary might be due to the ability of surface sediments to integrate these changes that
occur in the water column and act both as a repository and source of suspended materials.
Spatial variations of heavy metals in the surface sediments are the results of these
processes (Lin, et al 2003). Moreover, heavy metals generally exist in the particulate
phase adsorbed on the sediments. This behaviour of heavy metals in the estuary sediment
may be strongly influenced by adsorption to organic particles (sewage deposited at the
Korle lagoon estuary) and the inorganic particles in the lagoon (Table 4.4).
The particulate fraction may be transported with the sediments, which are governed by
sediment dynamics. Re-suspension of contaminated bed sediments may be caused by
strong tidal currents which may release a significant amount of heavy metals into the
water column (Zagar, 2006).
In addition, the relatively high levels of cadmium in the sediments compared to the Effect
Range Low (ERL) could be due to the high concentrations of dissolved salts or organic
matter which reduces its accumulation in sediments. Lead readily accumulates in
sediments and this could be the reason for the high levels recorded over the period.
Sediments are also thought to be the most important depositional site for particulate
copper transported from rivers; although remobilization may occur when sediments are
44

53. disturbed. The low copper levels recorded could be due to the regular mixing of the water
column due to its fluvial flow rate. Moreover, during high turbidity, greater levels of zinc
associated with suspended sediments are deposited with flocculated particles where it can
and where it can particularly accumulate in anaerobic sediments (Hunt et al, 1992).
Furthermore, fluctuation of heavy metals in the sediment could be due to the water
chemistry of the Korle lagoon estuary which may controls the rate of adsorption and
desorption of metals to and from sediments. The adsorption process could remove metals
from the water column and store these metals in the substrate. Desorption on the other
hand may return the heavy metals from sediment to the water column where recirculation
and bio assimilation could take place.
High salt concentrations could create increase competition between cations and metals
for binding site. This may cause metals to be driven off from sediments into the overlying
water, and this may often occur at estuary due to river flow inputs and tides.
Decreased redox potential under hypoxic conditions could change the composition of
metal complexes as metals bind to oxygen to form oxides and this could release the
heavy metal ions into the overlying water at the estuary.
pH may increase competition between metals and hydrogen ions for binding site. A lower
pH could also dissolve metal carbonate complexes releasing free ions into the water
column (Connell et al, 1984) as a result of the deposition of Sewage into the Korle
lagoon estuary.
According to Long et al. (1995), the concentration of copper, lead and Zinc recorded
occurs below the Effect Range Low value therefore their effects on fishes at the estuary
would rarely be observed. Cadmium concentration recorded was equal to the ERL but
45

54. below the ERM, which implies that fishes at the estuary could occasionally be affected
by Cadmium.
5.2. Heavy Metal effect in fish species
The mean concentration of Copper and Zinc in Pteroscion peli and Seriola dumerili were
lower as compared to the World Health Organization standards (2005). Cadmium and
Lead concentration were higher than the standard used. The lower levels of copper in the
flesh of both fishes could be due to the role of copper as an ingredient, normally in the
prosthetic group, of oxidizing enzymes which are important in oxidation-reduction
processes in fishes (Moolenaar, 1998). Also, copper in the cupric form may be the most
bio available (Grimwood, 1997) and could be readily accumulated by the fishes. It may
also be regulated or immobilized in many species and might not be biomagnified in the
food chain to any significant extent (CCREM, 1987).
Low level of Zinc recorded could be due to the up take of zinc readily by the study fish
species which may not reflect in the flesh tissue (Hunt et al, 1992). High level of lead
concentration could be due to the uptake and accumulation of lead by fish from water and
sediment and this may be influenced by various environmental factors. Consumers such
as (Pteroscion peli and Seriola dumerili) may take up lead from their contaminated food,
often to high concentrations, but without bio magnifications (WHO, 1995). Lead uptake
by fish could reach equilibrium only after a number of weeks of exposure. Typical
symptoms of lead toxicity include spinal deformity and blackening of the caudal region
as observed in the obtained fish samples. Tetra alkyl lead which is an inorganic lead
46

55. compounds may rapidly be taken up by fish and rapidly eliminated after the end of the
exposure (WHO, 1995).
Cadmium bio accumulates in organisms with the main uptake routes being dissolved
cadmium from the water column and cadmium associated with prey items. This could be
the reason for the high levels in Seriola dumerili and Pteroscion peli (WHO, 1992).
5.3. Variation in Metal Concentrations in Relation to Body Size
Large fishes for both species had a higher metal concentration in Pteroscion peli and
Seriola dumerili, but thoroughly there were no variations in metal concentrations between
the two size classes for both fish species and may be due to similarities in bioavailability
of the heavy metals to the two fish species (Pteroscion peli and the Seriola dumerili.)
from the Korle lagoon estuary, since both fish species are piscivorous (Ferreira et al.,
2004).
Smaller fishes might have accumulated high concentrations of heavy metals and this
might be due to their size, their feeding pattern and availability of the heavy metals
(FAO, 2012).
47

56. CHAPTER SIX
6.0. CONCLUSIONS
Heavy metal levels in fishes sampled were less than what was found in the sediment
samples. Heavy metals in sediment were continuously adsorbed and desorbed from
sediments into the overlying water column. The sediment quality in terms of the heavy
metals was acceptable but could pose a serious risk to the aquatic life of the lagoon
estuary in future if nothing is done to check metal accumulation in the Korle lagoon
estuary sediment.
The four metal concentrations in the flesh of the two fish species were lower for Zinc and
Copper but saw a high concentration for Cadmium and Lead as compared to the World
Health Organization Standard (2005) hence not safe for human consumption.
From the study however, it was also depicted that Pteroscion peli and Seriola dumerili
accumulate heavy metals in their flesh regardless of size.
6.1. RECOMMENDATIONS
The heavy metal concentrations in estuary have to be monitored on a more regular basis
for the effects of pollution on other fish communities. Although fish flesh (muscle) is the
most important part to be used for human consumption, fish skin and liver may also be
consumed to some extent. Target organs such as liver, kidney, gonads and gills, have a
tendency to accumulate heavy metals in high values and therefore a study has to be
conducted to assess the concentration of heavy metals in them.
48

57. Moreover, Secondary feeders like filter feeders (Mugil cephalus) and other herbivores
fishes from the Korle lagoon estuary could be studied to know their bio accumulation
levels and their magnification in the food chain.
Accumulation of heavy metals in fish flesh may be considered as an important warning
signal for fish health and human consumption. The present study shows that consumption
of fish from the Korle Lagoon estuary should be prohibited and should be discouraged
because of the high levels of Pb and Cd in the flesh of Seriola dumerili and Pteroscion
peli in both small and large sizes.
49

58. REFERENCES
Aanstoos , T. A., Nichols, S. P., Torres ,V. M. (1998). IEEE Transactions on Components,
Hybrids, and Manufacturing Technology, vol. 11, no. 4,October 1988, pp. 295-301.
Abdullah M. H, Sidi J. and Aris A.Z. (2007). International Journal of Environmental & Science
Education, 2(3), 69 – 74.
Agodzo, S. K., Huibers, F. P., Chenini, F., van Lier, J. B. and Duran, A. (2003). Use of
wastewater in irrigated agriculture. Country studies from Bolivia, Ghana and Tunisia.
Volume 2. Ghana. Wageningen University, Irrigation and Water Engineering Group,
Wageningen, The Netherlands.and bordeaux mixture applications. J. Environ. Qual., 27:
828–835.
Al-Yousuf, M. H., El-Shahawi, M. S. and Al-Ghais, S. M. (2000). Trace metals in liver, skin
and muscle of Ethrinus lentjan fish species in relation to body length and sex. Science of
Total Environment, 256: 87–94.
Aneum, (2010). Heavy Metal Poisoning, http://www.technologiez.net/2010/06/29/heavy-metal-
poisoning, Accessed from 18th September 2011.
AOAC (2003). Official methods of analysis of AOAC international.17th
edition, 2nd revision.
Gaitherburg, MD, US, association of analytical communities.
Armah, F. A., Yawson, D. O and Johanna, O. A. (2009). The Gap between Theory and Practice
of Stakeholder Participation: The Case Management of Korle Lagoon, Ghana; 5, 1 Law,
Environment and Development Journal (2009).P 73.
Ashraf , M., Hayat, M. Q., Jabeen S., Shaheen, N., Khan , M. A. and Yasmin G. (2010).
Artemisia L. Species Recognized by the Local Community of Northern Areas of Pakistan
as Folk Therapeutic Plants. J. Med. Plants Res., 4, 112-119.
Asuquo, F. E., Ewa-Oboho, I., Asuquo, E. F., and Udo, P. J. (2004). Fish Species Used as
Biomarker for Heavy metals and Hydrocarbon Contamination for Crossriver, Nigeria. The
Environmentalist, 2, 29-37.
Battarbee R.W. (1988). Lake Acidification in the United Kingdom 1800-1986 , ENSIS
Publishing, London.
50

59. Begum, A., Harikrishina, S. and Khan, I. ( 2009). Analysis of heavy metals in water, sediments
and fish samples of Madivala lakes of Bangalore, Karnataka, International Journal of
Chemtech Research , 20091, 2, 245-249.
Biney C. A. and Amuzu , A.T. (1995). Review of Korle lagoon studies. Accra Ghana, institute
of Aquatic Biology.
Boadi, K. O. and Kuitunen, M. (2002). Urban waste pollution in the Korle Lagoon, Accra,
Ghana. Environmentalist 22:301– 309.
Boakye, N. (2011). Assessment of the Heavy Metal Loads in the Flesh of Two Fish Species
from the Estuary of the Korle Lagoon, Ghana ,Bsc thesis, Kwame Nkrumah University of
Science and Technology (KNUST), Kumasi, Ghana.pp 10.
Carter, F. W. (1985). Pollution Problems in Post-War Czechoslovakia, Transactions of the
Institute of British Geographers new series, 10:17-44.
CCREM (Canadian Council of Resource and Environmental Ministers)(1987). Canadian Water
Quality Guidelines. Inland Waters Directorate, Environmental Canada,Ottawa.
contaminated by urban runoff. Marine Environmental Research, 55(2), 113-136.
Chao, L. N. and Trewavas E. (1990). Sciaenidae. In J.C. Quero, J.C. Hureau, C. Karrer, A. Post
and L. Saldanha (eds.) Check-list of the fishes the eastern tropical Atlantic (CLOFETA).
JNICT, Lisbon; SEI, Paris; and UNESCO, Paris. Vol. 2. (Ref. 3593) p. 813-826.
Cointreau, S. (1982). Environmental Management of Solid Wastes in Developing Countries.
International Journal of Basic & Applied Sciences, 10(3), pp. 37-57.
Connell, D.W., Miller G. J. (1984). Chemistry and Ecotoxicology of Pollution. John Wiley &
Sons, NY.
Doe, B. (2000). Accra Sustainable City Project, Ghana: Case Study No. 1. Pretoria, South
Africa: Melissa Project.
Entsua-Mensah, M. de Graft-Johnson K. A. A., Ansa-Asare, O.D., Amevenku F., Quarcoopome
T. and Biney C. A. (2004). The impact of salt winning on coastal biodiversity in Ghana.
Estuaries Tutorial, (2008). PS1 Chemistry Estuary, NOAA Ocean Service Education
URL:http://oceanservice.noaa.gov/education/kits/estuaries/ estuaries10_monitoring.html.
Accessed from 5th
February 2012.
51

60. European Union, (2002). Heavy Metals in Wastes, EuropeanCommission on Environment
(http://ec.europa.eu/environment/waste/ studies/pdf/heavy_metalsreport.pdf).
FAO,(1986). Major Exploited Fish Stocks retrieved from Institute of British Geographers,
10(1), pp. 17-44.
FAO, (2012). Fish Contaminants, Fisheries and Aquaculture development, Accessed from 23rd
March, www.fao.org/fishery/topic/14815/en.
Ferner, D. J. (2001). Toxicity, heavy metals. eMed. J. 2(5): 1.
Ferreira, G. A., Machado, A.L.S. and Zalmon, I.R. (2004). Temporal and Spatial Variation on
Heavy Metal Concentrations in the bivalve Perna perna (LINNAEUS, 1758) on the
Northern Coast of Rio de Janeiro State, Brazil. In Brazilian Archives of Biology and
Technology Vol.47, No. 2: pp. 319-327.
Fosmire, G. J. (1990). Zinc Toxicity. Am. J. Clin. Nutr. 51(2): 225 -227.
Gadzala-Kopciuch, R., Berecka, B., Bartoszewicz, J. and Buszewski B. (2004). Some
considerations about bio indicators in environmental monitoring .in publish Journal of
Environmental studies Vol 13,No(2004)453-462.
Gillanders, B. M., Ferrell, D. J., and Andrew, N. L. (1999). in press: Ageing methods for
yellowtail kingfish (Seriola lalandi) and results from age- and size-based growth models.
Fishery Bulletin 98.
Gleick, H.(1996). Basic Water Requirements for Human Activities: Meeting Basic Needs.
Pacific Institute for Studies in Development, Environment, and Security. International
Water Resources Association. Water International, 21 (1996) 83-92.
Grant, R. and Nijman J. (2004). The re-scaling of uneven development in Ghana and India.
Journal of Economic and Social Geography 95, 467-481.
Grau, A., Riera, F., Carbonell, E.(1992). Some protozoa and metazoans parasites of the
amberjack from the malaeric sea (Western Mediterranean), Aquaculture international
volume 7,number 5, 307-317.
Greenpeace, (2008). Chemical contamination at the e-waste recycling and disposal sites in
Accra and Koforidua, Ghana. Green peace Research Laboratories – Technical Notes
10/2008.
52

61. Grimwood M. J. and Dixon, E. (1997). Assessment of risks posed by list II metals to Sensitive
Marine Areas (SMAs) and adequacy of existing Environmental Quality Standards(EQSs)
for SMA protection. Report to English Nature.
Grobicki, A. M.W.(2001). An urban catchment management in a developing country:the lotus
river project, Capetown, South Africa. Wat. Sci. Tech. vol. 50, pp. 313-319, 2001.
Holum J. R. (1983). Elements of General and Biological Chemistry, 6t
Edition, John Wiley and
Sons, N.Y. pp. 324, 326, 353, 469.
Hunt, S. and Hedgecott, S. (1992). Revised Environmental Quality Standards for nickel in
water, WRc report to the Department of the Environment DoE 2685/1.
IMDC, (2011). Rehabilitation of Korle lagoon and its river system in Accra, Tender document
on Feasibity and Detailed Design Study, Ministry of works and Housing, Ghana
Government.http://www.imdc.be/project/rehabilitation-korle-lagoon-and-its-river-system.
.
Institute of Environmental Conservation and Research INECAR, (2000). Position Paper against
Mining in Rapu-Rapu, Published by INECAR, Ateneo de Naga University, Philippines
(www.adnu.edu.ph/Institutes/ Inecar/pospaper1.asp).
.
Jarup, L. (2003). Hazard of heavy metal contamination. Br. Med. Bull., 68: 167-182.
Kant, R. (2005). Remedial Strategy—Drinking Water Pollution, Chemical Engg. World,
January 2005. 3.
Karikari, A. Y., Asante K. A., and Biney, C. A. (2005). Water Quality Characteristics at the
Estuary of Korle Lagoon in Ghana. Unpublished paper. CSIR-Water Research Institute,
P.O. Box M32, Accra-Ghana.
Karikari, A. Y., Asante, K. Y.,and Biney, C. A. (1998). Water Quality Characteristics at the
Estuary of Korle Lagoon in Ghana. Accra: Water Resources Institute.
Kiliç, E. (2011). Chemical Engineer ( Hacettepe University) Chemical Division Manager – Cag
Kimya Turkey.
Kimani, N. G. (2007). Environmental Pollution and Impacts on Public Health: Implications of
the Dandora Dumping Site Municipal in Nairobi, Kenya, United Nations
Environment Programme,pp.1-31.
53

62. Kudesia, V. P. (2002). “Water Pollution—Toxicity of Metals”, Pragati Prakashan, Meerut
(2002) (India).
Lenntech Water Treatment and Air Purification, (2004). Water Treatment, Published by
Lenntech, Rotterdamseweg, Netherlands (www.excelwater.com/thp/filters/Water-
Purification.htm).
Lin Y. and Smart N. G. (2003). "Supercritical Fluid Extraction of Actinides and Heavy Metals
for Environmental Cleanup: A Process Development Perspective." Chapter 3 in
Supercritical Carbon Dioxide: Separations and Processes, ACS Symposium Series, vol.
860, ed. A. S. Gopalan, C. M. Wai, and H. K. Jacobs, pp. 23-35. American Chemical
Society, Washington DC.
Long, E. R., MacDonald, D. D., Smith S. L., and Calder, F. D. (1995). incidence of adverse
biological effect on within ranges of chemical concentration in marine and estuarine
sediments. Eviron.Manage.19:81-97
Longhurst, A. R. (1965). A survey of the fish resources of the eastern Gulf of Guinea. J. Cons.
int. Explor. Mer 29(3): 300-334
Lucky, T. D. and Venugopal, B. (2002). “Metal Toxicity in Mammals”, Plenum Press New
York.
Mance G., Brown, V. M., Gardiner J., Yates, J. (1984). Proposed environmental Quality
Standards for list II substances in water –chromium, technical report TR 207, WRc,
Medmenham
Marino, G., Mandich, A., Massari, A., Andaloro, F., Porrello, S., Finoia, M. G., Cevasco, F.
(1995). Aspects of reproductive biology of the Mediterranean amberjack (Seriola
dumerili Risso) during the spawning period. Journal of Applied Ichthyology 11: 9-24.
McCluggage D. (1991). Heavy Metal Poisoning, NCS Magazine, Published by The Bird
Hospital, CO, U.S.A. (www.cockatiels.org/articles/ Diseases/metals.html).
McGregor, G. (1995). Is the northern region the kingfish capital of the Pacific? Part 1: the fish.
Seafood New Zealand June 1995: 28-30.
54

63. Micale, V., Genovese, L., Greco, S., Perdichizzi, F. (1993). Aspects of the reproductive biology
of the amberjack, Seriola dumerili (Risso 1810). Special Publication European
Aquaculture Society 19: 413.
Moolenaar S.W. and Beltrami P. (1998). Heavy metal balances of an Italian soil as affected by
sewage sludge
Morrisey, D. J., Turner, S. J., Mills, G. N., Williamson, R. B. and Wise, B. E. (2003). Factor
affecting the distribution of benthic macrofauna in estuaries contaminated by urban
runoff. Marine Environmental Research, 55(2), 113-136.
NOAA, (1995). Sediment toxicity in Boston Harbor: Magnitude, extent, and relationships with
chemical toxicants. NOAA Technical Memorandum NOS ORCA, Coastal Monitoring
and Bioeffects Assessment Division, Silver Spring, MD, 85 pp. + 31 figures and 4
appendices.
Nai, G. G. (1994). Quantitative Evaluation of Pollution in the Korle lagoon. Ministry of Works
and Housing, Accra. 43 pp.
Nolan, K. and Orthomol J. (2003). Copper Toxicity Syndrome, Psychiatry 12(4): 270 – 282.
Nordlie, F. G., Szistowski, W. A. and Nordlie, W. C (1982). Ontogenesis of osmotic regulation
in the striped Mullet, Mugil cephalus l. Journal fish boil.20:79-86.
Odum, W. E. (1970). Utilization of the direct grazing and plant detritus food chains by the
striped mullet( mugil cephalus) pages 222-240 in A. 78Z’E-ed.
Ogwuegbu, M. O. C. and Muhanga, W. (2005). Investigation of Lead Concentration in the
Blood of People in the Copper belt Province of Zambia, J. Environ. (1): 66 – 75.
Peakall, R., Ruibal M., Lindenmayer D. B. (2003). Spatial autocorrelation analysis offers new
insights into gene flow in the Australian bush rat, Rattus fuscipes. Evolution 57: 1182–
1195.
Papathanassiou, E. and Zenetos A. (1993). A case of recovery in benthic communities following
a reduction in chemical pollution in a Mediterranean ecosystem. Marine Environ. Res. 36
131-152.
55

64. Ridgway, J. and Shimmield, G. (2002). Estuaries as Repositories of Historical Contamination
and their Impact on Shelf Seas. Estuarine, Coastal and Shelf Science (2002), 55, 903–
928.
Ries, L. G., Smith M. A., and Gurney J. G. (eds) (1999). Cancer Incidence and Survival among
Children and Adolescents: United States SEER Program 1975-1995, Bethesda, MD,
National Cancer Institute, SEER Program.
Scipeeps, (2009). Effects of Water Pollution. Retrieved from http://scipeeps.com/effects-of-
water-pollution/
Trivedi, R. C. (2008). “Water Quality Management in India”, Int. Conf. on Water Quality
Management, Feb. 2008, Nagpur.
Udedi, S. S. (2003). From Guinea Worm Scourge to Metal Toxicity in Ebonyi State, Chemistry
in Nigeria as the New Millennium Unfolds, 2(2): 13–14.
UN-WWAP, (2003). United Nations World Water Assessment Programme. The World Water
Development Report 1: Water for People, Water for Life. UNESCO: Paris, France.
UNECE, (2008). Environmental Policy, Treaties, Protocol on heavy metals, The 1998 Aarhus
protocol on Heavy metals.
UNICEF and WHO (2008). UNICEF and World Health Organization Joint Monitoring
Programme for Water Supply and Sanitation. Progress on Drinking Water and Sanitation:
Special Focus on Sanitation. UNICEF, New York and WHO, Geneva, (2008).
United Nations Environment Programme /GRID-Arendal, (2009). accessed 27th
November
2011://www.grida.no/publications/vg/waste/page/2858.aspx.
UN-Water, (2009). World Water Day brochure, date accessed 30th
October
2011//www.unwater.org/worldwaterday/downloads/wwd09brochureenLOW.pdf.
Washington, DC: The World Bank .
Vaas, K. K. (2007). Conservation and restoration of lakes and wetlands, Taal 12th World lake
conference, Jaipur, India 2007.
Vié, J. C., Hilton-Taylor, C. and Stuart, S. N. (eds.) (2009). Wildlife in a Changing World – An
Analysis of the 2008 IUCN Red List of Threatened Species. Gland, Switzerland: IUCN.
180 pp. Available at http://data.iucn.org/dbtw-wpd/edocs/RL-2009-001.pdf.
56

65. Woo, P. T. K., Sin Y. M. and Wong M. K. (1993). Environ. Biol. of Fishes, 37: 67-74.
WHO, (1992). Environmental health Criteria No.135_Cadmium-Environmental aspects World
Health Organization Geneva.
WHO, (1995). Environmental health criteria No165, lead, inorganic. IPCS,World Health
Organization.
WHO Codex Alimentarius Commission (2005). Codex General Standard for Contaminants and
Toxins in Food. Schedule 1. Maximum and Guideline Levels for Contaminants and
Toxins in Food.
Wu Y., Falconer R., Lin B. (2005). Modelling trace metal concentration distributions in
estuarine waters. Estuary Coast Shelf Sci 2005; 64: 699–709.
Yilmaz , A. B. (2005). Comparison of heavy metal levels of Grey Mullet (Mugil cephalus L.)
and sea bream (Sparus aurata L.) caught in Iskendrun Bay (Turkey).Turk. J. Vet. Anim.
Sci., 29: 257-262.
Young, R. A. (2005). Toxicity Profiles: Toxicity Summary for Cadmium, Risk Assessment
Information System, RAIS, University of Tennessee.
Zagar, D. (2006). Modelling of mercury transport and transformation processes in the Idrijca
and Soca river system. Sci Total Environ 2006; 368(1): 149–63.
57