AASCIT Journal of Environment

2017; 2(5): 48-55

http://www.aascit.org/journal/environment

ISSN: 2381-1331 (Print); ISSN: 2381-134X (Online)

Keywords Pesticide Residues,

Organochlorines,

Soil,

Water,

Floodplains,

GC-MS,

Minna

Received: August 15, 2017

Accepted: September 6, 2017

Published: October 13, 2017

Assessment of Organochlorine Pesticide Residues in Soil and Water from Fadama Farming Communities in Minna, North Central, Nigeria

Ogbonnaya Ikechukwu Chikezie1, *

, Mann Abdullahi2,

Yisa Jonathan2, Bala Abdulalahi

1

1Department of Soil Science and Land Management, Federal University of Technology, Minna,

Nigeria 2Department of Chemistry, Federal University of Technology, Minna, Nigeria

Email address ogbonnayachike@gmail.com (O. I. Chikezie) *Corresponding author

Citation Ogbonnaya Ikechukwu Chikezie, Mann Abdullahi, Yisa Jonathan, Bala Abdulalahi. Assessment of

Organochlorine Pesticide Residues in Soil and Water from Fadama Farming Communities in

Minna, North Central, Nigeria. AASCIT Journal of Environment. Vol. 2, No. 5, 2017, pp. 48-55.

Abstract The high pesticide residue in soil and water in the floodplains in Minna is of great

concern because the soil is used for cereal and vegetable cultivation and the water used

for domestic purposes. Therefore, organochlorine multi-pesticide residue analysis were

determined in soil and water collected from the vegetable growing floodplains in Minna,

North Central, Nigeria, where urban and peri-urban agriculture is practiced with

extensive application of synthetic pesticides. Analysis was carried out using the gas

chromatograph with mass spectrometric (GC-MS) detection technique. Organochlorine

pesticide residues detected in soil and water in Minna included endosufan-II, p,p'-DDT,

δ-BHC and heptachlor. Heptachlor and p,p’-DDT were the most common detected

organochlorines in the soil and the water samples. All the detected pesticide residues in

soil and water had concentrations that greatly exceeded the maximum residue limits

(MRLs). Heptachlor had (11.310 ± 0.46 mgkg-1

) > 0.03 mgkg-1

, δ-BHC (0.581 ± 0.32

mgkg-1

) > 0.02 mgkg-1

, p,p-DDT (0.296 ± 0.04 mgkg-1

) > 0.01 mgkg-1

, and endosulphan-

II (0.056 ± 0.03 mgkg-1

) > 0.02 mgkg-1

. Plant uptake of pesticides poses health risks to

domestic livestock that forage on crop stubble and consumers of food products from

these animals. The need for regular and stringent monitoring of pesticide residues in soil

and water in the floodplains in Minna, North Central, Nigeria is advocated while farmers

are adviced to adopt good agricultural practice.

1. Introduction

Organochlorine pesticide residues most commonly found in soil and water are

pesticides that are intentionally applied to cultivated crops to attack crop pests and

diseases (FAO/WHO, 2004). Global reports show that organochlorine pesticide usage

has increased significantly during the past three decades (Gilden et al., 2010). The

extensive use of pesticides for agriculture and non-agricultural purpose has resulted in

their enrichment in various environmental matrices, especially, soil water and food

(Darko and Akolo, 2008; Cardenas-Gonzalez et al., 2013). Modern and mechanized

49 Ogbonnaya Ikechukwu Chikezie et al.: Assessment of Organochlorine Pesticide Residues in Soil and Water from

Fadama Farming Communities in Minna, North Central, Nigeria

agriculture cannot operate without any form of chemical

pesticide of some sort, food production would probably

decline precipitously in many areas, prices of food would

soar for higher and food shortages would become more

severe (Uygun et al., 2005).

High levels of pesticide residues arising from improper

and unregulated application and multiple sprays of sub-lethal

doses have been reported to be responsible for the poisoning

and several adverse health hazards in both rural and urban

areas in Nigeria and Niger State in particular (NAFDAC,

2004; Berrade et al., 2010). According to the Centers for

Disease Control and Prevention (CDCP) Organochlorine

pesticides are ubiquitous environmental contaminants

because they break down very slowly.

In the European Union (EU), hexachloro-benzene (HCB),

dichlorodiphenyltrichloroethane (DDT), chlordane and

hexachloro-cyclohexane (HCH, which exists as different

forms, or “isomers”, one of which, γ-HCH, is lindane) has

been banned. According to (Yang et al., 2005), they are all

persistent and bio-accumulative chemicals, found widely in

the environment, wildlife and humans. Due to legislative

action in developed countries, the levels of organochlorine

pesticides are slowly declining. The DDT, chlordane and

HCB are classified as persistent organic pollutants (POPs)

under the Stockholm Convention of (2011). Ritter et al.,

(2007) stated that lindane is designated as a POP under the

European Commission (EC) Protocol, and is under

consideration for inclusion under the Stockholm Convention.

The two main groups of organochlorine insecticides are

the DDT-type compounds and the chlorinated alicyclics.

Their mechanism of action differs slightly: The DDT like

compounds work on the peripheral nervous system, and

prevent gate closure after activation and membrane

depolarization. (Da-Cuna et al., 2011). Chlorinated

cyclodienes include aldrin, dieldrin, endrin, heptachlor,

chlordane and endosulfan. They are hazardous

organochlorines, about 2 to 8 hour exposure to these OCPs

may lead to the depression of the central nervous system

(CNS) activity, followed by hyperexcitability, tremors, and

then seizures (Hayat et al., 2010). Other examples include

dicofol, mirex, kepone and pentachlorophenol. These can be

either hydrophilic or hydrophobic depending on their

molecular structure.

Some types of organochlorides have significant toxicity to

plants or animals, including humans. Dioxins, produced

when organic matter is burned in the presence of chlorine,

and some insecticides, such as DDT, are persistent organic

pollutants which pose dangers when they are released into

the environment. For example, DDT, which was widely used

to control insects in the mid-20th century, also accumulates

in food chains, and causes reproductive problems (eggshell

thinning) in certain bird species. Some organochlorine

compounds, such as sulfur mustards, nitrogen mustards, and

lewisite, are also used as chemical weapons due to their

toxicity. However, the presence of chlorine in an organic

compound does not ensure toxicity. Some organochlorides

are considered safe enough for consumption in foods and

medicines.

The present study investigates the pollution level of

organochlorine pesticide residues in soil and water of fadama

communities in Minna, North Central, Nigeria, where urban

and peri-urban agriculture is practiced with extensive inputs

of synthetic pesticides and agrochemicals to improve

agricultural production.

2. Methodology

The Study area is in Minna the capital of Niger State,

Nigeria. It lies between longitude 9° 40' N to latitude 6° 27' E

and longitude 9° 33' N to latitude 6° 35' E. It is in the North

Central region of Nigeria covering an area of about

100,899km2 with a population of about 5,17,1107 [G Nat.

Population]. The study area is characterized by three seasons:

the cool, dry (Harmattan) season (October- January), hot dry

season (February-April) and rainy season (June-September).

The mean annual rainfall in the area is about 1200 mm, while

the minimum and maximum temperatures are 26°C and 34°C

respectively (Federal Meteorological Agency, Minna, 2011).

Temperature rarely falls to 22°C. Wet season temperature

average is about 29°C. The peaks are 34°C (February to

March). Minna lies in the Guinea Savanna agro-ecological

zone which is characterized by vegeteation comprising of tall

trees with grasses and shrubs. The soil possess large amount

of conditionally water stable aggregates (FDALR, 1985).

Sampling and Sample Selection

Four floodplains at different parts of Minna (Bosso,

Chanchage, Maikunkele and Maitumbi) were selected based

on their geographic proximity to elevated centres of

population and the presence of urban and peri-urban fadama

cultivation with widespread use of pesticides

From the four floodplains, soil and water samples were

taken at four points. Grab sampling technique (Staare et al.,

2000) was employed in the collection of the surface water

samples. The water temperature and pH were measured

directly from the water samples using pH meter (Hanna

Instrument H1.991301) before transferring into scrupulously

cleaned screw-cap bottles under ice pack pending their

extraction.

Soil samples were taken from four floodplains at five

points at the depth of 0-20 cm using the soil auger and a

composite made for each floodplain. The soil samples were

air dried in the laboratory for about 1 week, picked for

obvious extraneous material, ground with porcelain mortar

and pestle, and sieved through 2 mm wire mesh. The samples

were stored in brown bottles prior to extraction. The

sampling points were all geo-referenced with Global

Positioning System (GPS Garmin eTrex10 Model).

Materials and Preparation

All the reagents used were of analytical grade from

AASCIT Journal of Environment 2017; 2(5): 48-55 50

ACUSTAT Standards, Inc. USA. and included n-Hexane,

acetone, diethyl ether, ethyl acetate, methylene chloride,

sodium sulphate, silica gel, toluene and methanol. Proper

cleaning of the glass wares was ensured to avoid sample

contamination. The glass wares used for organochlorine

pesticide determination were cleaned as recommended by the

method 1669 of United States Environmental Protection

Agency (USEPA), (2007). The activated silica gel clean up

procedure and the anhydrous sodium sulphate used for drying

the samples were prepared in accordance with USEPA

method 1699.

Figure 1. Map of Minna, Niger State showing the study site.

51 Ogbonnaya Ikechukwu Chikezie et al.: Assessment of Organochlorine Pesticide Residues in Soil and Water from

Fadama Farming Communities in Minna, North Central, Nigeria

Physico-chemical Analysis of the Soil

Samples

The particle size distribution of the soil was determined

using the Bouyoucous hydrometer method (IITA, 2009),

involving mainly the dispersion of the soil using sodium

hexametaphosphate (Calgon). The Walkley Black wet

oxidation method (Schulte, 1995) was used to determine the

organic carbon content of the soil and hence the organic

matter. The moisture content was determined by the

gravimetric method while the cation exchange capacity was

determined by the NH4OAC displacement and summation of

the exchangeable cations (Na, K, Ca and Mg). pH was

determined in-situ using the pH meter (Hanna Instruments HI

991301).

Extraction of Organochlorine Pesticide

Residues from Soil and Water Samples

Extraction of soil samples was carried out using the

method described by Ize-Iyamu et al., (2007) with slight

modifications. A mixture of 25 g sample and 50 g granular

sodium sulphate was ground into a powdery consistency

using a mortar and pestle. The ground sample was extracted

with 150 cm3 of a mixture of n-Hexane and acetone (1:2).

The extract was transferred into a round bottomed flask and

concentrated to about 20 cm3 on a water bath maintained at

50°C - 55°C. The remaining solvent in the concentrated

extract was evaporated using a rotary evaporator (Buchi R

110 Brinkmann TM

) to about 5 cm3. The concentrated extract

was quantitatively transferred to a centrifuge tube,

concentrated on a nitrogen evaporator to 0.5 cm3 and diluted

to 2 cm3 in hexane pror to GC-MS analysis.

Clean up Procedures for the Sample Extract

Various components with large molecular size such as

lipids, proteins, pigments and residues are co-extracted with

pesticide molecules (Tiryaki et al., 2006). These substances

are referred to as ‘dirts’ and are necessarily removed from the

extracts prior to chromatographic analysis, as they may cause

interferences in the chromatographic system and detection,

and may also damage the GC equipment. However, in this

study, no clean- up was required for the water samples as

they were relatively clean with no obvious co-extracted dirts.

Clean up of Soil Extracts

The concentrated soil extract was washed by liquid-liquid

partitioning with 120 cm3 of saturated sodium sulphate and

250 cm3 of distilled water. After shaking, the aqueous was

drained into a beaker and the hexane was transferred to a

separatory funnel. The aqueous layer was returned to a 500

cm3 separatory funnel and re-extracted with 40 cm

3 of

dichloromethane in hexane. The organic layers were

combined in a 250 cm3 separatory funnel and gently washed

with 100 cm3 distilled water for about 30 seconds. After the

aqueous layer was discarded, the organic layer was filtered

through sodium sulphate, evaporated to near dryness on a

rotary evaporator. The sides of the flask were rinsed down

with 120 cm3 of hexane and evaporated to about 1.0 cm

3. The

sample extract was quantitatively transferred to centrifuge

tube, concentrated on a nitrogen evaporator to 0.5 cm3 and

diluted to 2.0 cm3 final volume and subsequently presented

for GC-MS analysis.

Gas Chromatograph-Mass Spectrometry

Instrumentation

All the extracts (soil and water) were determined with the

aid of a gas chromatograph equipped with a mass-selective

detector (GC-MS), an auto-sampler and a split-split less

injector. The DB-5 fused silica capillary column of 30m x

0.25µm i.d. x 0.25µm film thickness was coated with cross

linked 5% phenyldimethyl polysiloxane. The carrier gas was

helium (99.999% purity) at a flow rate of 1.0ml/min. Oven

temperature was maintained initially at 40°C for 1min,

increased at 12°C/min to 280°C, then at 20°C/min to 215°C,

at 100°C/min to 265°C and finally at 200°C/min to 290°C

and held for 8 min. Injection volume was 1µL, injected in

split less mode at injection temperature of 250°C. The mass

spectrometer was operated in electron impact (EI) ionization

mode with a detector voltage of 700V, ion source

temperature of 200°C, GC interface temperature of 320°C

and emission current of 150 µV. Acquisition mode was

selected ion Monitoring (SIM).

Table 1. Names, Retention Time, Correlation Coefficient, Limit of Detection and Maximum Residue Limit of the Pesticides.

Pesticide (Common name) Retention Time

(mins)

Correlation Coefficient

(r2)

Limit of Detection

(mgkg-1) *(LOD)

Maximum Residue Limit

(mgkg-1) **(MRL)

α-BHC 12.46 0.9993 0.011 0.010

Heptachlor 13.86 0.9977 0.011 0.030

Dieldrin 17.38 0.9958 0.021 0.050

Endosulphan-II 18.05 0.9986 0.014 0.020

p,p'-DDT 18.93 0.9985 0.007 0.100

δ-BHC 12.46 0.9984 0.010 0.020

Lindane 12.46 0.9994 0.026 0.010

p,p'-DDD 18.96 0.9819 0.014 0.010

*LOD- Limit of Detection of GC-MS

**MRL- Maximum Residue Limit (EU, FAO/WHO, 2006)

AASCIT Journal of Environment 2017; 2(5): 48-55 52

Figure 2. Chromatogram of 15 Organochlorine Standard Pesticide mix (0.50 mgL-1) in acetonitrile.

3. Results and Discussion

The results of the physio-chemical properties of the soil

samples from the floodplain under study are presented in

Table 2. The pH of soil from Minna floodplains were slightly

acidic and ranged between 6.0 and 6.5. It is noteworthy that

most soils of the Nigerian Guinea savannah show similar pH

trend, Federal Department of Agriculture and Land

Resources (FDALR), (1985). The soil organic matter content

of the soil were moderately high and ranged between 13.51

gkg-1

and 15.61 gkg-1

It supported the growth of both cereals

and vegetables, this may be due to the fact that the tests soils

are surface soil samples (0-20cm depth) where

decomposition, synthesis process and other biological

activities are progressively taking place (Lee et al., 2003).

The particle size analysis of the soils studied revealed that the

fadama soils were predominately sandy clay loam (SCL)

soils. This implies that pesticide residues and organic

pollutants may not easily migrate down the soil profile to

pollute groundwater due to the high clay content. The

Electrical Conductivity (EC) of the soil were low and ranged

between (201.45 µScm and 121.38 µScm-1

), however, the

Cation exchange capacity of the soils were moderately high

and ranged between 9.58 Cmolkg-1

and 12.02 Cmokg-1

The

low level of EC and CEC coupled with the high clay content

of the soils may retard the movement and mass transfer of

pesticide residues to contaminate groundwater. The pesticide

residues are adsorbed by the fine clay particles which will

restricts the movement of the pesticides down the soil profile

to pollute groundwater, similarly, due to the high organic

matter content of the soil, and duet to the organic synthesis

and bio-transformtions progressively taking place in the soil,

pesticide residues are may only be transported and transfered

to the root zones where they are taken up by plants (Lee et al.,

2003).

Table 2. Physicochemical Characteristics of Selected Fadama Soil samples from Minna.

Minna Sand (%) Silt (%) Clay (%) Textural Class

(U.S.D.A) pH (CaCl2) EC mScm-1 OM gkg-1

CEC

Cmolkg-1

Moisture

(%)

Bosso 58 18 24 SCL 6.0 121.38 14.59 9.58 94.05

Chanchaga 60 17 23 SCL 6.2 132.43 13.51 12.02 93.01

Maikunkele 61 13 26 SCL 6.5 138.45 15.61 10.30 96.09

Maitumbi 60 18 22 SCL 6.4 135.32 14.72 12.91 92.97

EC—Electrical Conductivity

OM—Organic Matter

CEC– Cation Exchange Capacity

SCL – Sandy Clay Loam

53 Ogbonnaya Ikechukwu Chikezie et al.: Assessment of Organochlorine Pesticide Residues in Soil and Water from

Fadama Farming Communities in Minna, North Central, Nigeria

The mean concentration of organochlorine pesticides

identified in soil is presented in Table 3. Two pesticide

residues were detected in soil and samples from the floodplains

in Minna and these include – Endosulphan and p,p'-DDT. The

mean concentration of pesticide residues detected in soil

samples from Minna floodplains are endosulphan that ranged

between 0.049 mgkg-1

and 0.056 mgkg-1

and while p,p'-DDT

ranged between 0.289 mgkg-1

and 0.298 mgkg-1

and All the

pesticides detected in soil in the four floodplains under study

had pesticide residue concentrations that exceeded the

maximum residue limits (MRL).

Table 4 depicts the mean concentration of organochlorine

pesticide residues in water samples from Minna. The residues

include heptachlor which mean concentration ranged from

10.211 mgkg-1

to 11.312 mgkg-1

and δ-BHC that ranged

between 0.497 mgkg-1

to 0.581 mgkg-1

. All the pesticide

residues identified and quantified in water in the floodpains

in Minna greatly exceeded the maximum residue limits

(MRLs). Heptachlor and p,p'-DDT were the frequently

detected organochlorines in the soil and the water samples.

The study revealed that the exceedingly high concentrations

of pesticides detected in the soil and surface water from the

floodplains probably may have been contributed from some

non-point sources such as run-off applications of pesticide

upstream which ends up in the floodplains, atmospheric fall-

out or chemical drift during application and practices such as

washing spraying equipment’s in surface water could also be

a source of contamination of soil and water in the floodplains.

The results show that the transport and transfer of the

organochlorine pesticides in the soil was restricted by the

high clay, and organic matter content and the slightly acidic

nature of the soils of the floodplains. The slightly acidic

nature of the soils enhances the adsorption and binding of

pesticide residues to the clay minerals, thereby, increasing

their residency period in the soil which allows transport of

pesticides down to the root zone where due to the high

organic matter content of the soils and the synthesis and bio-

transformations taking place, the pesticides are transported to

the root zones where they are taken up by vegetables and

cereal crops that are cultivated in the floodplains (Kellogg et

al., 2000).

The results of this study when compared with USEPA and

the Codex Alimentarius FAO/WHO, 2004 MRL indicate that

the concentration of the pesticide residues detected in soil

and water greatly exceeded the allowable maximum residue

limits. Most pesticide residues identified in this study are

known to be neurotoxic, others have been found to be

carcinogenic, teratogenic and depress immune responses,

while others have been identified as endocrine disruptors,

this implies that they can affect human growth and

reproduction (Monsour, 2004; Jobling et al., 1995; Koprucu

et al., 2006). The high concentrations of organochlorine

pesticide in soil and water in Minna floodplains pose a risk to

the human and aquatic life and provide an indication of

unregulated application of hazardous pesticides in the

floodplains in Minna.

Table 3. Concentration (mgkg-1) of Organochlorine Pesticide Residues in Soil in Minna.

Pesticide Bosso (Mean±

SD) (mgkg-1)

Chanchaga

(Mean± SD)

(mgkg-1)

Maikunkele

(Mean± SD)

(mgkg-1)

Maitumbi

(Mean±SD)

(mgkg-1)

Retention

time (mins)

Identified

Molecular

weight (gmol-1)

MRL

(mgkg-1)

α-BHC Nd Nd Nd Nd Nd Nd 0.01

Heptachlor Nd Nd Nd Nd Nd Nd 0.03

Dieldrin Nd Nd Nd Nd Nd Nd 0.05

Endosuphan-II 0.056 ± 0.03 0.054 ± 0.02 0.049± 0.02 0.051± 0.03 18.05 406.00 0.02

p,p'-DDT 0.296 ± 0.04 0.298 ± 0.02 0.293 ± 0.03 0.289 ± 0.02 18.94 354.00 0.10

δ-BHC Nd Nd Nd Nd Nd Nd 0.02

p,p'-DDD Nd Nd Nd Nd Nd Nd 0.01

γ-Lindane Nd Nd Nd Nd Nd Nd 0.01

trans-Permethrin Nd Nd Nd Nd Nd Nd 2.00

cis-Permethrin Nd Nd Nd Nd Nd Nd 2.00

n = 20 samples; MRL =Maximum Residue Limit; Nd = not detected

Table 4. Concentration (mgL-1) of Organochlorine Pesticide Residues in Water in Minna.

Pesticide Bosso (Mean±

SD) (mgL-1)

Chanchaga

(Mean± SD)

(mgL-1)

Maikunkele

(Mean± SD)

(mgL-1)

Maitumbi

(Mean±SD)

(mgL-1)

Retention

time (mins)

Identified

Molecular

weight (gmol-1)

MRL

(mgL-1)

α-BHC Nd Nd Nd Nd Nd Nd 0.01

Heptachlor 11.310 ± 0.46 10.321 ± 0.21 11.054 ± 0.32 10.981 ±0.26 13.86 372.50 0.03

Dieldrin Nd Nd Nd Nd Nd Nd 0.05

Endosuphan-II Nd Nd Nd Nd Nd Nd 0.02

p,p'-DDT Nd Nd Nd Nd Nd Nd 0.10

δ-BHC 0.581 ± 0.32 0.497 ± 0.20 0.534 ± 0.04 0.512 ± 0.03 12.46 290.00 0.02

p,p'-DDD Nd Nd Nd Nd Nd Nd 0.01

γ-Lindane Nd Nd Nd Nd Nd Nd 0.01

trans-Permethrin Nd Nd Nd Nd Nd Nd 2.00

cis-Permethrin Nd Nd Nd Nd Nd Nd 2.00

n = 20 samples; MRL =Maximum Residue Limit; Nd = not detected

AASCIT Journal of Environment 2017; 2(5): 48-55 54

4. Conclusion

The study clearly established that organochlorine pesticide

residues constitute a major source of contamination in soil

and water in the floodplains in Minna. The study also

revealed that DDT, heptachlor, endosuphan and δ-BHC are

used indiscriminately and without regulation in the

floodplains in Minna.

Based on the above findings the relevant regulatory

agencies of government should urgently legislate, regulate

and intensify the advocacy in the proper use of hazardous

pesticides and agrochemicals in agricultural farm lands.

Good agricultural practice (GAP) should be encouraged and

awareness created on the need for the use of protective

clothing, storage regulation, distribution and good personal

hygiene adopted by farmers that regularly use synthetic

hazardous pesticides and agrochemicals. Further studies

should be carried out on other pesticide groups such as

carbamtes and synthetic pyrethroids used in the floodplains

which have not been investigated in this study to ensure that

their residues are within safety limits.

Acknowledgements

The authors acknowledge the support of the Central

Laboratory of the National Food Drugs Administration and

Control (NAFDAC), Lagos for supporting the analyses of the

soil and water samples. We also appreciate Professor A.

Gachanja, Administrator, Pan African Chemistry Network

(PACN) and Dr. Steven Lancaster of the Royal Society of

Chemists (RSC) for sponsoring the Principal Investigator to

the Workshop held at Jomo Kenyata University of Science

and Technology, Nairobi, Kenya on GC-MS Technique and

interpretation.

References

[1] Adeboyejo, O, A., Clarke, E. O., and Olarinmoye, M. O. (2011). Organochlorine pesticide residues in water, sediments, fin and shell-fish samples from Lagos Lagoon complex, Nigeria. Researcher, 3, 38-45.

[2] Berrade, H., Fernandez, M., Ruz, M. J., Molto, J, C., Manes, J., and Font, G. (2010). Surveillance of pesticide residues in fruits from Valencia during twenty months (2004/05). Food Control, 21, 36-44.

[3] Cardenas-Gonzalez, M., Gaspar-Ramirez, O., Perez-Vazquez, F. J., Alegria-Torres, J. A., Gonzalez- Amaro, R., and Perez-Maldonado, I. N. (2013). p,p'-DDE, a DDT metabolite, induces proinflammatory molecules in human peripheral blood mononuclear cells "in vitro". Experimental Toxicology Pathology, 65, 661-665.

[4] Da Cuna, R. H., Rey, V. G., Piol, M. N., Guerrero, N. V., and Maggese, M. C. (2011). Assessment of the acute toxicity of the organochlorine pesticide endosulfan in Cichlasoma dimerus (Teleostei, perciformes). Ecotoxical Environmental Safety, 74, 1065-1073.

[5] Darko, G. & Akolo, O. (2008). Dietry intake of

organophosphorous pesticide residues through vegetables from Kumasi, Ghana. Food and Chemical Toxicology, 46, 3703-3706.

[6] FAO/WHO (2001). FAO/WHO (2004). Codex Alimentarius commission additivies and contaminants Joint FAO/WHO food standards programme. ALIWORM 01/ 12A, pp, 1-289. Pesticide programme residue monitoring (accessed May 2010).

[7] FDALR (1985). The recognizance soil survey of Niger State, Nigeria: Federal Department of Agriculture and Land Resources, 1985.

[8] Gilden, R. C., Huffling, K. & Sattler, B. (2010). Pesticides and health risks. Journal of Obstetric, Gynecologic, and Neonatal Nursing, 39 (1), 103-110.

[9] Hayat, K., Ashfaq, M., Ashfaq, U., and Ahmad-Saleem, M. (2010), Determination of pesticide residues in blood samples of villagers involved in pesticide application at Disrict Vehari (Punjab). Pakistan Journal of Environmental Science and Technology, 4 (10), 666-684.

[10] IITA (International Institute of Tropical Agriculture). (2009). Legume and cereal seed production for improved crop yields in Nigeria. Proceedings of the Training Workshop on production of Legume and Cereal seeds, Edited by H. A Ajeigbe., T. Abdoulaye, and D. Chikoye.

[11] Ize-Iyamu, O. K., and Egwakhide, P. A. (2007). Concentration of residues from organochlorine pesticides in water and fish from some rivers in Edo State, Nigeria, International Journal of Physical Science, 2, 237-241.

[12] Jobling, S., Reynolds, T., White, R., Parker, M., and Sumpter, J. (1995). Chemicals found to mimic human estrogens. Environmental Health Perspectives, 103, 582-587.

[13] Kellogg, R. L., Nehring, R., Grube, A., Goss, D. W., and Plotkin, S. (2000). Environmental indicators of pesticide leaching and runoff from fields. United States Department of Agriculture National Resources Conservation Service.

[14] Koprucu, S., Koprucu, K., Ural, M., Ispir, U., and Pata, M. (2006). Acute toxicity of organnophosphorous pesticide diazinon and its effects on behavior and some haematological parameters of finferling European catfish. Journal of pesticide Biochemistry and physiology, 86, 99-105.

[15] Lee, S. E., Kim, J. S., Kennedy, I. R., Park, J. W, Kwon, G. S., and Koh, S. C. (2003). Biotransformation of an organochlorine insecticide, endosulfan, by Anabaena species. Journal of agricultural and Food Chemistry, 51 (5), 1336-1340.

[16] Mansour, S. A. (2004). Pesticide exposure -Egyptiian scene. Toxicology, 198, 91-115.

[17] NAFDAC (2004). National Agency for Food and Drug Administration and Control Consumer Safety Bulletin: NAFDAC Regulated Products, pp. 9.

[18] Osibanjo, O., and Adeyeye, A. (1995). Organochlorine residues increase. Toxicology, 54, 460-465.

[19] Osibanjo, O., and Adeyeye, A. (1997). Organochlorine pesticide residues in foodstuffs of animal origin in Nigeria. Bulletin of Environmental Contamination and Toxicology, 58, 206-21.

55 Ogbonnaya Ikechukwu Chikezie et al.: Assessment of Organochlorine Pesticide Residues in Soil and Water from

Fadama Farming Communities in Minna, North Central, Nigeria

[20] Ritter, L., Solomon K. R., Forget, J., Stemeroff, M., O’Leary, C. (2007). Persistent organic pollutants: An Assessment Report on: DDT, Aldrin, Dieldrin, Endrin, Chlordane, Heptachlor, Hexachlorobenzene, Mirex, Toxaphene, Polychlorinated Biphenyls, Dioxins and Furans. Prepared for The International Programme on Chemical Safety (IPCS), within the framework of the Inter-Organization Programme for the Sound Management of Chemicals (IOMC).

[21] Schulte, E. E. (1995). Recommended soil organic matter test. In: E. E. Schulte (ed.) Recommended soil testing procedures for the North-eastern United State. 2nd Edition.

[22] Staare, J. U., Benhoft, A., Derocher, A., Gabrielsen, G. W., Gokbyr, G. W., and Henriksen, E (2000). Organochlorines in top predators at Svalbard – occurrence, levels and effects. Toxicology Letters, 112, 103-109.

[23] Stockholm convention. (2011). Persistent organic pollutants. [Cited 2012 February 10th]; Available from: http://chm.pops.int/Convention/The POPs/tabid/673/default.aspx.

[24] Tiryaki, O., and Baysoyu, D. (2006). Estimation of sample processing uncertainty for chlorpyrifos residue in cucumber. Accredit. Quality Assurance, 10, 550-552.

[25] US Environmental Protection Agency (USEPA). (2006). Guidance for assessing chemical contaminant data for use in fish advisories. 2: Risk Assessment and fish consumption limits. Available at: http/www. Epa/gov/ost/fishadvice/vol. 2/index.httml.

[26] US Environmental Protection Agency (USEPA) Method 1699 (2007). Pesticides in water, soil, sediment, biosolids, and tissue by high resolution gas chromatography with high resolution mass spectrometry. Available online at www.water.epa.gov (accessed 6th August 2012.

[27] Uygun, U., Koksel, H., and Alti, A. (2005). Residue levels of malathion and its metabolites, and fenitrothion in post-harvest treated wheat during storage, milling and baking. Food Chemistry, 92-643.

[28] World Health Organization (WHO), (2011). Guidelines for drinking water quality. Fourth Edition. World Health Organization, pp, 179-191.

[29] Yang, R., Ji, G., Zhoe, Q., Yaun, C., and Shi, J. (2005). Occurrence and distribution of organochlorine pesticides (HCH and DDT) in sediments collected from East China sea. Environmental International, 31, 799-804.