This document summarizes the implications of pesticide usage in Nigeria. It discusses how about 15,000 metric tons of pesticides containing 135 chemicals are imported annually, which has led to persistence in the environment affecting ecosystems and non-target organisms. Pesticides have been found to contaminate food, soil, water and living organisms like fish in Nigeria. The document analyzes several studies that have found pesticide residues in foods, rivers, groundwater, and fish in Nigeria above permissible limits. Long-term exposure to pesticides is linked to health issues in humans like cancer, birth defects and nervous system impacts. Better regulation and monitoring of pesticide usage is needed to reduce environmental and health effects in Nigeria.

1. See discussions, stats, and author profiles for this publication at: http://www.researchgate.net/publication/249993929
IMPLICATIONS OF PESTICIDE USAGE IN
NIGERIA
ARTICLE · OCTOBER 2012
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Nosakhare Osazee Erhunmwunse
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Retrieved on: 22 September 2015

2. Tropical Freshwater Biology, 21 (1) (2012) 15- 25 15
http://www.ajol.info/index.php/tfb ; DOI: http://dx.doi.org/10.4314/tfb.v21i1.2
IMPLICATIONS OF PESTICIDE USAGE IN NIGERIA
*N.O. Erhunmwunse., A. Dirisu and J.O. Olomukoro
Department of Animal and Environmental Biology, University of Benin,
P.M.B. 1154, Benin City, Nigeria.
*Correspondence: donsazy@yahoo.co.uk
ABSTRACT
The occurrence of pesticides in our environment as a result of the
indiscriminate or intentional use has resulted in its persistence in the
environment, thereby affecting the ecosystems and non target organisms.
Acute and chronic pesticide poisoning usually results from consumption of
contaminated food, chemical accident in industries and occupational
exposure in agriculture. About 15,000 metric tons of pesticides comprising
about 135 pesticide chemicals are imported annually into the country. They
are the major causes of cancer, cardiovascular disease, dermatitis, birth
defects, morbidity, impaired immune function, neurobehavioral disorder
and allergy sensitization reaction. In Nigeria, food test carried out on 217
different food items revealed the presence of DDT, Aldrin and Dieldrin to be
above maximum allowable concentration level which ranged from 1.2-
2160µg kg-1
. The detection of these pesticides in soil, drinking water and
other animals is of great interest. The failure to establish data-base from
past incidents in order to avert future occurrences has posed a huge
problem to the society at large. The need for epidemiological data
collection from past exposure, development of less toxic pesticides and legal
requirement regarding toxicological and ecological effect before the
importation of pesticides into the country will further reduce the impact of
toxic pesticides on human health in the country.
Key words: Pesticides, Environment, Health, Pollution, Nigeria.
INTRODUCTION
Pesticide is any substance or mixture of substance intended for prevention,
destroy, or controlling any pest, including vectors of human or animal diseases,
unwanted plants or animals causing harm during, or otherwise interfering with the
production, processing, storage, transport, or marketing of food (FAO, 1986).
Pesticide can also be used as vector control and agriculture control agent in public
health programmes (WHO, 1990). The development of pesticides became
widespread after the Second World War; they were introduced to avert the
problems of plant diseases and pest control. A survey on pesticides usage in
Trop. Freshwat. Biol. 0795-0101/12/15USD ©2012 Idodo Umeh Publishers Ltd., Nigeria

3. 16 N.O. Erhunmwunse et al.
Nigeria indicated that about 15,000 metric tons annually of pesticides comprising
about 135 pesticide chemicals marketed locally under 200 different produce
brands and formulation were imported during 1983-1990 thus making Nigeria one
of the largest pesticides users in sub-Sahara Africa (Osibanjo, 2002).
Although the benefits of pesticides cannot be overemphasized, their uses
raise a number of environmental concerns such as potential toxicity to humans and
other animals (Kamrin, 1997). Over 98% of sprayed insecticides and 95%
herbicides reach a destination other than their target species, including non-target
species, air, water and soil. Pesticides usage is one of the causes of water pollution;
some are persistent organic pollutant and contribute to soil contamination
(Bradman, 1999). The incidence of pesticides poison can result from the misuse,
storage of pesticides close to consumable food stuff, the use of pesticides
containers for household, improper disposal of used containers, treatment of food
stuff with pesticides, transport of food and pesticides in the same lorry and cars
such as in the case of Iraq 1970 (WHO, 1990). The following categories of people
are exposed to pesticides either accidentally or occupationally: pesticides
manufacturers, vendors or sellers, mixers, transporters, loaders, operators of
application equipment, growers, pickers and clean-up workers and the consumers
of food items treated with pesticides.
A joint Food and Agriculture Organization/World Health Organization
Food Contamination Monitoring programme found Aldrin, Dieldrin, DDT,
Lindane, Heptachlor and Heptachlor epoxide in human breast milk (GEM, 1986).
The WHO and UN Environmental program estimated that each year, 3 million
workers in agriculture in the developing world experience severe poisoning from
pesticides; about 18,000 of who die. According to one study, as many as 25
million workers in developing countries may suffer mild pesticide poisoning
yearly (WHO, 2006). Important human diseases in the tropics are transmitted by
vectors or intermediate host, like Molluscs or insects that can be killed by
Molluscicide or insecticides (WHO, 1984e). Edwards (1986) identified five main
vector – borne diseases for which pesticides are used: malaria, filariasis,
onchocerciasis, schistosomiasis and trypanosomiasis. Others include dengue fever,
dengue haemorrhage fever, chagas disease, leishmaniasis, louse-borne typhus
amongst others. This is of great importance to the government of the country as
huge amount of pesticides are used indiscriminately for the control of these
organisms without proper knowledge.
The adverse effects of pesticides contamination is not limited to the
environment but, extended to human health. Hazards arising during the application
of pesticides are mainly due to lack of information, knowledge and awareness,
poor legislation or of enforcement of legislation, and sales in the open market of
high pesticides (WHO, 1990). The severity of any effect from exposure to
pesticide depend on the dose, the route of exposure, how easily the pesticide is
absorbed, the type of effect of the pesticides and its metabolites, the accumulation
and persistence in the body and lastly, the health status of the individual (WHO,
1990).

4. Implications of Pesticide Usage in Nigeria 17
Soil Quality
The use of pesticides over the years has made it possible to increase crop yields
and food production (Lee, 1985). However, intensive use of pesticides results in
some environmental problems such as contamination of soil. When pesticides are
applied to destroy pests and pathogens, only 15% of the applied amount hits the
target, with the remaining 85% being distributed in soils and air (Leonila, 2002).
Pesticides residue in the soil can move from the surface when they dissolved in
runoff water, or percolate down through the soil, and eventually reach the
groundwater (FAO, 2000). Leachate from open dump and landfills are therefore
recognized as sources of Oragnophosphorus pollution of surface water in Africa
(Arebun, 1990). This is of great concern to expert in the field of toxicity as most of
the pesticide pollution goes unnoticed in Nigeria, as underground water supply has
become the most important supply of water in urban areas.
Result of the survey carried out by Aikpokpodion et al. (2010) to
determine the degradation of Endosulfan in Ibadan soil and to evaluate the effect
of the recommended rate (0.25% a.i) of the insecticide (Endosulfan-35Ec) on some
soil chemical properties showed that application of Endosulfan-35EC significantly
increased the acidity, magnesium and iron content of the treated soil, reduced the
concentration of calcium, Potassium and sodium in the treated soil. An average of
3.91ng/g soil of Endosulfan was present as residue in the soil six months after
application. There was 85% population reduction of nematode as a result of
Endosulfan application. Aikpokpodion et al. (2010) concluded that the application
of Endosulfan pesticide is moderately persistent in Ibadan soil and hinders
availability of some soil nutrients.
Water
Pesticides have been found in surface and underground water. They enter natural
water from direct application for control of aquatic weeds, trash fish, aquatic
insects, percolation and run off from agricultural lands, drift from industrial waste
water and discharge from waste waters from clean up equipment’s used for
pesticide formulation and application (FEPA, 1991). Okaniyia et al (2009)
investigated organochlorine and polychlorinated residue in some rivers in the
northern part of Nigeria. They discovered that high level of organochlorine and
polychlorinated pesticides was as a result of the extensive use of Lindane in
fishing and Aldrin in cultivated farmland close to these water bodies. Although,
these pesticides level were found to be less than obtainable results in America but,
the bioaccumulation in fishes and other aquatic life is of great concern.
Evidence of underground water pollution by some pesticides in Nigeria
has been established by Osibanjo and Aiyejuyo (1994), the study shows that total
DDT and heptachlor found in Ibadan ground water exceeded the WHO limits for
these chemicals in drinking water. The disinfection of water by chlorination which
produces trihalomethanes (THMs) which are potential carcinogens is a common
practice in Nigeria and most of the other African countries. The concentration of
individual and total THMs in tap water from some Nigerian towns was
investigated.

5. 18 N.O. Erhunmwunse et al.
Out of the five THMs, only bromoform was not detected at all and only Ibadan
water samples contained the three remaining THNs. Tap water samples from
Ibadan, Lagos, Oyo town, Ilorin and Kaduna contained detectable levels of THM.
The highest THM value of 220mgl-1
detected in Ibadan is higher than the
permissible limits in Germany (25mg l-1
), Holland (75 mg l-1
) and USA (100 mg l-
1
) (Oliver and Nicol, 1984).
The occurrence of organochlorine pesticides in major rivers in Nigeria
which serve as drinking water source to the vast majority in the country for
domestic and industrial purposes has been established (Osibanjo, 2002). The
works of Agunloye (1984), and Nwankwoala and Osibanjo (1992) show the level
and occurrence of some organochlorine pesticides in some rivers in Nigeria
compared to other rivers in the continent of Africa. The results show that fresh and
coastal waters are contaminated as a result of agricultural and industrial activities
respectively, although, the figures were below WHO and FMEnv permissible
limits.
PESTICIDE EFFECTS ON LIVING ORGANISMS
Fishes
Fishes are source of protein and food to a vast majority of Nigeria population. The
presence of pesticides residues in water bodies make it a source of contamination
to fishes and human who consume that fishes that bioaccumulate these pesticides
in the marine and fresh water ecosystems making them unfit for human
consumption. Organochlorine pesticides residues were measured in three species
of fish (Tilapia zilli, Ethmalosa fimbriata and Chrysichthys nigrodigitatus) in
Lagos lagoon. The following pesticides were analyzed for their presence in the fish
samples: DDT (pp’ 1,1,1-trichloro-2,2-bis-(4-chlorophenyl ethane), DDD, DDE
(pp 1,1-dichloro-2, 2-bis-(4-chlorophenyl) ethylene, HCH (gamma 1,2,3,4,5,6-
hexachlorocylohexane, HCB (Hexachlorobenzene), Dieldrin (1,2,3,4,10,10-
hexachloro - 6, 7 –epoxy -1, 4, 4a, 5, 6, 7,8, 8a octahydro - 1, 4, 5, 8
dimethanonapthalene) and transnonachlor. The mean concentration of the
organochlorine pesticides ranged from 0.01-8.92 ppm, although the concentration
of organochlorine pesticides in the fishes were below the extraneous residue limit
of 5 ppm, set by the Codex Alimentarious Commission of FAO/WHO (1997) but,
above allowable Federal Environmental Protection Agency (FEPA) and the
concentration was higher in adult fishes compared to their juvenile stages (David
et al., 2008).
Although prior to the above study, Ize-iyamu et al. (2007) indicated that
organochlorine pesticides present in fish samples were higher than those present in
water samples from same river. This was attributed to the fact that pesticides have
affinity for fat, settle down rapidly in fatty tissue in the fish by the process of
ingestion, dermal absorption and bioaccumulate in fishes until they are consumed.
Since the level of organochlorine were found to be higher than the FMEnv limits,
it is therefore important for the government of the nation and all agencies involved
to take precautionary measures in order to reduce the health effect of these
pesticides in humans the largest consumers of these commodities.

6. Implications of Pesticide Usage in Nigeria 19
Osibanjo and Jensen (1980) reported that the deliberate killing of fish with
Lindane and DDT was responsible for the high concentration values of these
pesticides in fish samples. Further studies carried out by Famoyi (1987), quantified
9 organochlorine present in fish samples in southern part of Nigeria (Cross River
and Akwa Ibom state). Osibanjo and Bamgbose (1991) detected the presence of
some organochlorine pesticides in 94 samples of 25 marine fish species, 14
samples of 7 shellfish for a period of 2 years. The fish samples contained higher
concentrations of Aldrin, Heptachlor, HCB and Lindane and lower concentrations
of DDT and PCBs compared to shell fish. The levels of occurrence of these
pesticides were found to be lower than the results from temperate region by other
literature.
Food
Several food samples have been analyzed for the presence of pesticides in Nigeria
amongst which are the work done by Etonihu et al. (2011) on maize grains, white
beans and sorghum which were purchased randomly from open markets in
Nasarrawa and Plateau states respectively to analysize the presence of pesticides.
The results revealed the presence of 28 pesticides represented in these food items.
Ingestion of contaminated foods is a major source of human exposure to
organochlorine pesticides and the dietary source has been established by the
collection of food stuffs. Osibanjo (2002) showed that 217 fruit and vegetable;
four major cereal (rice, maize, sorghum and soybeans), as well as food stuffs of
animal origin from different location within Nigeria were analyzed for the
presence of organochlorine. Meat, pulses and cereals were discovered to contain
DDT, Aldrin and Dieldrin above maximum residue limit (MRL) while, others
contain the pesticides below MRL (Osibanjo and Adeyeye, 1995; Osibanjo and
Adeyeye, 1997; Adeyeye and Osibanjo, 1999).
TABLE 1
Overall mean concentration (µg kg-1
) of Organochlorine residue in Nigeria
foodstuff.
MRL Fruits Vegetable Tuber Cereals Cow Pig Goat Fish
DDT 1000-5000 6.9 28.3 30.4 81 164 510 141 4.80
Aldrin 20-200 1.9 2.1 8.0 8.0 28 244 61 -
Dieldrin - - - 32 45 312 337 14 -
Heptachlor 200 ND ND ND 9.5 ND ND ND 3.60
DDE - 5.8 4.7 12 29 106 374 90 -
MRL (Maximum Residue Limits) FAO/WHO, 1986. ND (Below detection limit)
(Osibanjo, 2003)
Human
Various concentration levels of pesticides have been found in animals including
humans which happens to be on the highest trophic level in the ecosystem. As

7. 20 N.O. Erhunmwunse et al.
discussed earlier, animals are exposed to pesticides through various means
including consumption of foods, contact, inhalation, and absorption. Biological
indicators of pesticides include: urinary residues and their metabolites, adipose and
serum residues, breast milk residue, skin and hair residue, Cholinesterase
determination and increased blood coagulation (Davies et al., 1982). The first case
of human exposure to pesticide in Nigeria occurred in 1958, all members of the
family of a local chief who was a prominent cocoa farmer at Okebode in South
western Nigeria were hospitalised after eating a leaf earlier sprayed with Lindane
(Ibatayo, 2006). In 2004, Carbofuran pesticides residues found on several batches
of noodles manufactured in Nigeria may have resulted in 23 reported cases of
vomiting and one death (Ibatayo, 2006). Table 2 show the health effects of some
pesticides commonly used in Nigeria agriculture. Environmental contamination by
Organochlorines pesticides of aquatic bodies, lands, wildlife, food stuff, human
diet, human blood and mother’s breast milk in Nigeria, and other sub-regions in
Africa continent has been established (Osibanjo, 2002). Blood samples from koko
in Delta State, (where illegal dumping of toxic waste from Italy in 1987-1988
occurred) were collected for analysis of toxins from four categories of individuals;
resident close to dump site, dockworkers, neighbours and lastly hospital workers.
The concentration of fat, PCB’S and Lindane recorded in the blood of resident
near the koko dump sites were highest in the study area. The result was compared
with results in Taiwan cases of similar incident and was found that the Koko
incident victims had lower level of Lindane than the victims from Taiwan (Odare,
1991; Osibanjo, 2002).
In 1963, the Insecticide Testing Unit (ITU) of the World Health
Organization in Lagos, Nigeria, undertook a program to evaluate the effect of two
Carbamate and one Organophosphorous insecticides in a village scale trail, the
toxicological information gained in the trail showed that one of the Carbamate
tested (3-Isopropylphenyl N-MethylCarbamate) was too toxic to man to be used as
a residual insecticide in houses (Vandekar, 1965).
CONCLUSION
It is obvious that pesticides contamination is on the increase in the country as a
result of its usage for different activities. The absence of data on pesticide’s related
poison on the population in Nigeria makes it difficult to ascertain the exact effect
on human health in the country. Effort should be geared towards establishing
appropriate medical surveillance and record keeping of workers involved with
pesticides in Nigeria. The Nigerian government should train specialist in the field
of occupational health and safety management and establish research centre’s to
carryout epidemiological and metabolic studies of the affected person’s.
Manufactures should develop less toxic or hazardous pesticides, increase the
awareness of pesticides usage and set up modalities to develop specific mechanism
to obtain data from health centre and create basic national exposure-assessment
data of pesticides produced in order to know the nature of damage caused by such
pesticide(s).

8. Implications of Pesticide Usage in Nigeria 21
TABLE 2
Health of some pesticides commonly used in Nigeria agriculture
Pesticides Application Health Effects References
Aldicarb It is a systemic insecticide effective for
the control of aphids, nematodes, flea,
thrips, white flies etc
Inhibitor of cholinesterase WHO, 1990
Aldrin Effective against wire worm and to
control termites.
Increased D-glutaric acid
metabolism
Hunter et al., 1971
Paraquat It is used as a plant desiccant effective
against grasses
Contact dermatitis, cellular
proliferation in the lung.
Fetal intoxication, chronic
fibrotic changes.
Almeida, 1978;
Bainova, 1982;
WHO, 1984C;
Adam, 1983;
WHO, 1990;
WHO 1984c
Captafol It is a protective, wide spectrum foliage
an soil fungicide
Contact dermatitis WHO, 1990;
Adam, 1983
2-4-D It is a selective post emergence
herbicide used for the control of many
annual broadleaf weeds
Contact dermatitis WHO, 1990
Mancozeb It is a protective fungicide, effective
against a wide range of foliage disease
Contact dermatitis WHO, 1990
Barban Herbicides Skin sensitization, allergic
reaction and rash contact
dermatitis
Almeida, 1978;
Bainova, 1982;
Adam, 1983
Benomyl Eradicant fungicides Skin sensitization, allergic
reaction and rash contact
dermatitis
Almeida, 1978;
Bainova, 1982;
Adam, 1983
DDT Effective against wide variety of
insects, including domestic insects and
mosquitoes
Skin sensitization, allergic
reaction and rash,
carcinogenic
Almeida, 1978;
Bainova, 1982;
Adam, 1983
Lindane It is used against sucking and biting
insects
Skin sensitization, allergic
reaction and rash. Contact
dermatitis. Enzyme
induction
Almeida, 1978;
Bainova, 1982;
Adam, 1983;
Kolmodin et al.,
1969
Zineb Protectant fungicide Skin sensitization, allergic
reaction and rash,
Photoallergic reaction
Almeida, 1978;
Bainova, 1982;
Adam, 1983
Malathion Wide range insecticides used against
aphids, red spider, thrips and
leafhoppers.
Skin sensitization, allergic
reaction and rash
Almeida, 1978;
Bainova, 1982;
Adam, 1983
Hexachlorebenzene
(HCB)
Acaricide Photosensitivity, bulbae
formation, deep scarring,
permanent loss of hair,
skin atrophy and chlorance
Almeida, 1978;
Bainova, 1982;
WHO, 1990
2, 4, 5-T Herbicides-hormone weed killer Chlorance Almeida, 1978;
Bainova, 1982
Pentachlorophenol Molluscicide Chlorance Almeida, 1978;
Bainova, 1982
Ethylene dibromide Fumigant nematocide Mutagenic IARC, 1988

9. 22 N.O. Erhunmwunse et al.
Pesticides Application Health Effects References
Hydrazine Herbicides Mutagenic IARC, 1988
Chlordecone Insecticide Carcinogenic. Enzyme
induction, increase D-
glutaric acid metabolism
ARC, 1988
Kolmodin et al.,
1969
Guzelian et al.,
1980
Chlorophenols Fumigant Carcinogenic IARC, 1988
1-3-
dichloropropene
Fungicide and nematocide Carcinogenic IARC, 1988
Chlorophenoxy Harbicide Carcinogenic IARC, 1988
Mirex Stomach insecticide Carcinogenic IARC, 1988
Nitrofen Organic herbicide Carcinogenic IARC, 1988
Hexachlorocyclohe
xanes
Fungicide Carcinogenic IARC, 1988
Sulfallate Protective fungicide Carcinogenic IARC, 1988
Toxaphene Organic herbicide Carcinogenic IARC, 1988
Dibromochloroprop
ane
Nematocide Sterility in male WHO, 1990
Dinitrophenols Fungicide and Acaricide Uncoupling of oxidation
phosphorylation
Weinbach, 1957
Dinitrocresols Acaricide and fungicide Uncoupling of oxidation
phosphorylation
Weinbach, 1957
Dicofol Acaricide and non-fungicide Effect on the immune
system
WHO, 1990
Organotin Acaricide and protective fungicides Effect on the immune
system
WHO, 1990
Diquat Dessicants, defoliants and haulm killer Cataract formation WHO, 1990
Parathion Organic: non-systemic insecticide Inhibitor of cholinesterase WHO, 1990
Fenthion Organic: non-systemic insecticide Muscular changes Misra et al., 1985
Methyl bromide Fumigant – Rodenticide and
nematocide
Optic nerve atrophy Chavez et al.,
1985;
Abou-Donia &
Preissig, 1976a,
1976b
Phenoxyacid Hormone weed killers In male- increased risk of
abortion and malfunction
in their offspring. Enzyme
induction
WHO, 1984a;
Dossing, 1984
Dieldrin Used against ectoparasite, months,
beetle.
Increase D-glutaric acid
metabolism
Hunter et al., 1971
Folpet Protective fungicide Teratogenicity or fetal
toxicity
WHO, 1990
Pentachloronitroben
zene
Molluscicides Teratogenicity or fetal
toxicity
WHO, 1990
Captan It is foliage fungicide with protective
action
Teratogenicity or fetal
toxicity
WHO, 1990
Carbaryl It is contact insecticide and a fruit
thinner with a broad spectrum of
activity effective against many pests of
fruit.
Teratogenicity or fetal
toxicity
WHO, 1990
Pyrethroids Insecticide Peripheral neuritis WHO, 1990
Metachlor Selective pre-emergence herbicide Decrease in kidney weight WHO, 2006
Carbofuran Broad insecticide Cholinesterase inhibitor WHO, 2006

10. Implications of Pesticide Usage in Nigeria 23
Pesticides Application Health Effects References
Chorotoluron Post-emergence herbicide Cholinesterase inhibitor WHO, 2006
Cyanazine Pre and post-emergence herbicide Increase in adenomas and
carcinomas of the kidney
WHO, 2006
1, 2 dibromoethane Fumigant Increase tumour WHO, 2006
Fenoprop Herbicide Degeneration and necrosis
of hepatocytes and
fibroblastic proliferation
WHO, 2006
Heptachlor and
heptachlor epoxide
Broad-spectrum insecticide Kidney tumour WHO, 2006
Isoproturon Systemic herbicide Marked enzyme induction
and liver enlargement
WHO, 2006
Methyl-parathion Non-systemic insecticide and Acaricide Decreased cholinesterase
activities, sciatic nerve
dymyelination, anemia
WHO, 2006
Methoxychlor Broad-insectide Carcinogenic potential in
liver and testes
WHO, 2006
Molinate Herbicide Impairment of the
reproductive performance
WHO, 2006
Pyripoxyfen Broad-spectrum insecticide Increase in liver weight WHO, 2006
REFERENCES
Abou-Donia, M.B. & Preissig, S.H (1976a). Delayed neurotoxicity of leptophos:
toxic effect on the nervous system of hens. Toxicology and Applied
pharmacology,35, 269-282.
Abou-Donia, M.B. & Preissig, S.H. (1976b). Delayed neurotoxicity from
continuous low-dose of oral administration of leptophos to hens.
Toxicology and Applied pharmacology, 38, 595-608.
Adams, R.M. (1983). Occupational skin disease. New York, Grune and Strattion.
Adeyeye, A. & Osibanjo, O. (1999). Residues of organochlorine pesticides in fruit,
vegetable and tuber from Nigeria market. Science Total Environment
231:227.
Aikpokpodion, P.E., Lajide, L., Ogunlade, M.O., Ipinmoroti, R., Orisajo, S.,
Iloyanomon, C.I. & Fademi, O. (2010). Effect of Endosulfan on soil and
root-knot nematodes in cocoa. Journal of Applied Biosciences 26, 1640-
1646.
Almeida, W.F., Demello, D. & R-puga (1978). Influence of nutritional status on
the toxicology of food additives and pesticides. Galli, C.L. ed., Chemical
toxicology of food, Amsterdam, Elsevier/North Holland biomedical Press,
169-184pp.
Baba, A. A. (2008). Dangers of unsound management of obsolete pesticide in
Nigeria. A paper presented at Nigeria-Africa stockpiles program steering
committee (Nigeria-Asp).
Bainova, A. (1982). Dermal absorption of pesticides: Toxicology of pesticides,
World Health Organisation Regional Office for Europe, Copenhagen,
Demark. (European Cooperation on Environmental Health Aspects of the
Control of Chemicals, Interim Document 9), 41-53pp.

11. 24 N.O. Erhunmwunse et al.
Chavez, C.T., Hepler, R.S. & straatsma, B.R. (1985). Methyl bromide optic
atrophy. American journal of ophthalmology, 99, 715-719.
David A., Grace U., Chimezie A., & John Paul Unyimadu (2008). Organochlorine
Pesticide Residues in Fish Samples from Lagos Lagoon, Nigeria. American
Journal of Environmental Sciences 4(6), 649-65.
Davies, J.E., Freed, V.H. and Enos, H.F. (1982). An agrochemical approach to
pesticide management: some health and environmental consideration,
Miami, University of Miami, School of Medicine, 320pp.
Dossing, M. (1984). Non-invasion assessment of microsomal enzyme activity I
occupational medicine: present state of knowledge and future prospective:
International archives of occupational and environmental health, 53, 205-
218.
Edwards, C.A. (1986). Agrochemicals as environmental pollutant. In: van Hofsten,
B. and Ekstrom, G., ed. Control of pesticides application and residues in
food. A guide and directory 1986, Uppsala, Swedish Science Press 1-19pp.
Etonihu, A.C., Aminu, B.A., Ambo, A.I., & Etonihu, K. (2011). Iodine content and
pesticide residues of some Nigerian food grains. Continental J. Agricultural
Science 5 (1), 26-32.
Fayomi, S.F. (1987). BSc Thesis University of Ibadan, Nigeria
Food and Agriculture Organization (1999). Inventory of obsolete stock in Nigeria:
A Country Report.
Global Environmental Monitoring System (1986). Chemical contaminants in
foods: 1980-1983. Unpublished world health organisation document
WHO/EHE/FOS/86.5. Available on request from: Division of
Environmental Health, World Health Organisation, 1211 Geneva 27,
Switzerland.
Guzelian, P.S.G., Vranian, J.J., Boylan, W.J., Cohn & R.V., Blanke (1980). Liver
structure and function in patients poisoned with Chlordecone.
Gastroenterology, 78, 206-213.
Hunter, J., Carrella, M., Maxwell, J.D., Stewart, D.A. & Williams, R. (1971).
Urinary D-glutamic-acid excretion as attest for hepatic enzymes induction in
man. Lancet, 1, 572-575.
Ibatayo, O. (1987). Reducing agricultural pesticides poisoning in Su-Sahara
Africa: Beyond Zero-risk. Edward C. Booking (eds), Trends in Hazardous
Materials Research, Nova publishers: Hauppauge, NY.
International Agency for Research on Cancer (IARC) (1988). Overall evaluation
of carcinogenicity: An update of IARC monographs, Lyon IARC Evaluation
of Carcinogenic Risk to Human, supply. 7, 1-42.
Ize-Iyamu O.K., I.O. Abia and P.A. Egwaikhide, (2007). Concentrations of
residues from organochlorine pesticide in water and fish from some rivers in
Edo State, Nigeria. Int. J. Physical Sci., 2, 237-241.
Kolmodin, B., Azamor, D.L. & Sjoqvist, F.C. (1969). Effect of environment
factors on drug metabolism: Decreased plasma half life of antipyrine in
workers exposed to chlorinated hydrocarbon insecticides. Clinical
pharmacology and therapeutics, 10, 638-642.

12. Implications of Pesticide Usage in Nigeria 25
Leonila, M.V. (2002). Impact of agrochemical on soil and water quality. National
crop protection centre, university of the Philippines at Los Banos.
Misra, U.K., Nag, D., Mehra, M.K. & Ray, P.K. (1985). Some observation on the
maolua of pesticide workers. Human toxicology, 4, 135-145.
Nwankwoala. A.U., & Osibanjo, O. (1992). Sc. Tot. Env. 119:179.
Odaro O. (1991) MSc Thesis University of Ibadan, Nigeria.
Okeniyia, S.O., Egwaikhide, P.A., Akporhonore, E.E. & Obazee, I.E. (2009).
Distribution of Organochlorine and polychlorinated pesticides residue in
water bodies of some rivers in northern Nigeria. Electronic journal of
environment, Agriculture and Food Chemistry 8, (11): 1269-1274.
Oliver, B.G., & Charlton, M.N. (1984). Env. Sci Tech 18, 903.
Osibanjo, O. & Adeyeye, A. (1995). Organochlorine Pesticide Residue in Nigeria
Market. Bull Environ. Toxicol. 54, 460-465.
Osibanjo, O. & Adeyeye, A. (1997). Organochlorine Pesticide Residue in
foodstuff of animal origin in Nigeria. Bull Environ. Toxicol. 58, 206-212.
Osibanjo, O. & Bamgbose, ((1991) Review of chlorinated substance in marine fish
and shellfish of Nigeria. Marine Pollut. Bull., 21, 581-586.
Osibanjo, O. & Jensen, S. (1980). Ecological and environmental perspective of
pesticides pollution: in Akinyele O., Omueti (Eds), proceedings
conference on water pollution and pesticide residue in food.
Osibanjo, O., Biney, C., Calamari, N., Kaba, N., Mbome, I.L., Naeve, H.,
Ochumba, P.B.O. & Saad MAH (1994). Chlorinated Hydrocarbon
substances, Flood and Agriculture Organisation Fish Report 502:2.
Vandekar M. (1965). Observations on the Toxicity of Carbaryl, Falithion and 3-
Isopropyhenyl N-MethyCarbamate in a Village Scale Trial in Southern
Nigeria. Bull.Wld Hlth Org 33, 107-115.
Weinbach, E.C. (1957). Biochemical basis for toxicity of pentachlorophenol.
Proceedings of the national academy of science (USA), 43, 393-397.
World health Organisation (1984a). 2, 4-dichlorophenoxyactic acid (2, 4-D).
Geneva, Switzerland. WHO Environmental Health Criteria, No 29.
World Health Organisation (1984c). Paraquat and Diquat. Geneva, Switzerland.
WHO Environmental Health Criteria, No 39.
World Health Organisation (1984e). Chemical methods used the control
arthropods vectors and pest of public health importance. Geneva.
Environmental Health Criteria.
World Health Organisation (1990). WHO recommended classification of pesticide
by hazard and guidelines to classification 1990-1991. Unpublished WHO
document WHO/PCS/90.1. Available on request from: Division of
Environment Health, WHO, 1211 Geneva 27, Switzerland.
World Health Organisation (2006). WHO gives indoor use of DDT a clean bill of
health for controlling Malaria. Division of Environmental Health, WHO,
1211 Geneva 27, Switzerland.